Dissertations / Theses on the topic 'Irrigation salinity'
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Farr, C. R. "Salinity Distribution Under Drip Irrigation." College of Agriculture, University of Arizona (Tucson, AZ), 1985. http://hdl.handle.net/10150/204075.
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Ismail, El-Sayed El-Shafei. "Computer simulation of crop response to irrigation accounting for salinity." Thesis, University of Newcastle Upon Tyne, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.278807.
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Saleh, Mohamed Al-Azhari M. "Modelling irrigation water management under water shortage and salinity conditions." Thesis, University of Edinburgh, 2006. http://hdl.handle.net/1842/11348.
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The usefulness of mathematical models in identifying efficient management strategies under uncertain conditions is, however limited by the theories used in models as well as by the availability and quality of field data that can be used in the calibration and validation of these models. Many models have been developed and used to simulate water and solute flux in the crop rootzone. This thesis describes the development and application of two different models, the WAVE and UNSATCHEM models to simulate water and solute transport in the vadose zone and their effect on crop transpiration and yield. The WAVE model was modified to include the effect of salinity on crop transpiration, and used to simulate soil water balances, to investigate long-term salinity build-up in the root zone, and in conjunction with a crop yield response model to assess their effect on crop yield. The practicality of the modelling approach in the establishment of optimal irrigation and drainage practices is considered through application to the Makhtaaral region of South Kazakhstan. The impact of several irrigation and drainage scenarios was evaluated. Optimal irrigation and drainage strategies for sustainable crop production have been derived. The application of the UNSATCHEM model as a multi-species model to the Makhtaaral region is also demonstrated for the evaluation of the current irrigation and drainage practices. For the problem considered in this study, the WAVE model along with the crop yield response model can be used as a tool for assessing the impact of different irrigation and drainage scenarios on crop yield. The results demonstrate that the modelling approach is robust and applicable under arid and semi-arid conditions and to a wide range of water shortage and salinity.
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HASSAN, HESHAM MAHMOUD. "ESTIMATION OF EVAPOTRANSPIRATION AND IRRIGATION UNIFORMITY FROM SUBSOIL SALINITY (ARIZONA)." Diss., The University of Arizona, 1985. http://hdl.handle.net/10150/188001.
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Irrigation uniformity, efficiency, leaching fraction, salt and water ages, and evapotranspiration rate were estimated from subsoil salinity data for three cotton fields in Arizona. The estimation of these parameters was based on the assumption of steady-state water and salt flow through the crop root zone. The levels of salt concentration in the irrigation water were 21.3, 11.5, and 11.6 meq/L for Fields 1, 2, and 3, respectively. Two of these fields were furrow irrigated, and the third was subsurface drip irrigated. Each field was sampled for salt concentrations to a depth of 1.5 m at 10-15 sites. A total of 514 soil samples were collected. Significantly lower salt concentrations were observed in the soil profiles in Fields 1 and 2 compared to Field 3, but lower variations in the salt concentrations were observed in Field 3 compared with Fields 1 and 2. These variations in salt concentration could be due to restricted water movement within the soil profile caused by stratified soil. Since a soil-water extract model indicated little or no chemical precipitation of salt within the soil profile, there was no need to correct the data for chemical effects. The calculated irrigation uniformity was highest in Field 3 and lowest in Field 1. This may be related to more accurate land leveling in field 2 than Field 1. The irrigation efficiencies were 83.0%, 89.0%, and 80.0% for Fields 1, 2, and 3, respectively. The correlation coefficient between the ages of salt and water was 0.98, 0.99, and 0.97 for Fields 1, 2, and 3, respectively. Leaching fraction was highest in Field 3 and lowest in Field 2. Mean actual ET calculated from the Blaney-Criddle method were 372, 314, and 308 mm for Fields 1, 2, and 3, respectively. Mean ET calculated from the salinity data were 1,250, 1,590, and 1,140 mm for Fields 1, 2, and 3, respectively. Statistically significant correlation coefficients were, however, found between both methods of estimating ET. These values were 0.97, 0.86, and 0.93 for Fields 1, 2, and 3, respectively.
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Brown, Paul, and Jim Walworth. "Factors Contributing to Development of Salinity Problems in Turf." College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2010. http://hdl.handle.net/10150/147000.
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8 pp.The bulletin reviews the factors contributing to the development of salinity and sodium problems in desert turfgrass systems. Key factors include water restrictions, poor water quality, irrigation management, drought and poor soil structure.
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Henggeler, Joseph Charles. "The conjunctive use of saline irrigation water on deficit-irrigated cotton." Texas A&M University, 2004. http://hdl.handle.net/1969.1/1416.
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Cotton (Gossypium hirsutum) is able to survive relatively large levels of both water and
salinity stress. The objective of this study was to evaluate cotton lint production and soil
salinization under a conjunctive use strategy using saline water at deficit levels. A three-year
experiment applying irrigation at deficit amounts on cotton was conducted in Pecos, Texas on a
Hoban silty clay loam. Treatments were four irrigation water qualities, conjunctively applied.
Initial irrigation was with water having an electrical conductivity (ECIW) of 4.5 dSm-1,
representing about one-third of the total amount of water applied. Thereafter, treatments were
applied using water of varying ECIW, e.g., 1.5, 4.5, 9.0, and 15.0 dSm-1 for all subsequent
irrigations. Total irrigation plus rain was approximately two-thirds of full water requirements.
Lint yields for the three years averaged 1050, 1008, 809, and 794 kg ha-1, respectively, and
treatment levels did not decline over time. However, the soil salinity levels of the three more
saline treatments increased throughout the test period. Yields declined due to salinity prior to
reaching the published threshold value (Maas and Hoffman, 1977) of ECe = 7.7 dSm-1. Under
the deficit conditions of two-thirds of the full water requirements, the threshold level was
lowered to 4.5 dSm-1. The overall yield loss that resulted from limiting water by one-third was
three times > than the yield loss from even the highest salinity treatment. Relative lint yield was
reduced 3% for each dSm-1 of ECIW. The pre-dawn and solar-noon leaf water potential values
decreased at a rate of 0.026 and 0.042 MPa per dS m-1 of the ECIW, respectively. Study
conclusions were that yields within treatments remained stable for three years. However, the
increase of salinity in the soil profile indicated that long-term viability of using highly saline
water conjunctively is impractical under deficit irrigation conditions. In the short-term,
however, saline water of up to 15.0 dS m-1 can be used at mid-season under deficit conditions on
Hoban silty clay loam soil to secure 75% of the yield level obtained by using high quality water
if a pre-plant irrigation of medium quality water is first applied.
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Buchannan, Sam Faculty of Science UNSW. "Salinity hazard mapping and risk assessment in the Bourke irrigation district." Publisher:University of New South Wales, 2008. http://handle.unsw.edu.au/1959.4/41451.
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At no point in history have we demanded so much from our agricultural land whilst simultaneously leaving so little room for management error. Of the many possible environmental impacts from agriculture, soil and water salinisation has some of the most long-lived and deleterious effects. Despite its importance, however, land managers are often unable to make informed decisions of how to manage the risk of salinisation due to a lack of data. Furthermore, there remains no universally agreed method for salinity risk mapping. This thesis addresses these issues by investigating new methods for producing high-resolution predictions of soil salinity, soil physical properties and groundwater depth using a variety of traditional and emerging ancillary data sources. The results show that the methodologies produce accurate predictions yielding natural resource information at a scale and resolution not previously possible. Further to this, a new methodology using fuzzy logic is developed that exploits this information to produce high-resolution salinity risk maps designed to aid both agricultural and natural resource management decisions. The methodology developed represents a new and effective way of presenting salinity risk and has numerous advantages over conventional risk models. The incorporation of fuzzy logic provides a meaningful continuum of salinity risk and allows for the incorporation of uncertainty. The method also allows salinity risk to be calculated relative to any vegetation community and shows where the risk is coming from (root-zone or groundwater) allowing more appropriate management decisions to be made. The development of this methodology takes us a step closer to closing what some have called our greatest gap in agricultural knowledge. That is, our ability to manage the salinity risk at the subcatchment scale.
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Lewis, Marjorie Fay. "The significance of episodic recharge in the Wheatbelt of Western Australia /." Connect to thesis, 2000. http://eprints.unimelb.edu.au/archive/00000682.
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Khandker, Md Humayun Kabir. "Crop growth and water-use from saline water tables." Thesis, University of Newcastle Upon Tyne, 1994. http://hdl.handle.net/10443/580.
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How much water can a crop abstract from below a saline water table and how does the salinity affect yield? These questions are important because shallow groundwater may represent a substantial resource in flat, low-lying areas, but may also represent a threat to sustainability where salinity is high. A series of experiments in a glasshouse aimed to elucidate irrigation management practice under salinity conditions and to develop a root uptake model under both osmotic and matric stresses. The extraction of soil water and groundwater by lettuce and perennial ryegrass crops were measured in three instrumented lysimeters. Water table depths were 0.6,0.9 and 1.2 rn below the soil surface. The lysimeters were initially saturated with saline water (electrical conductivity 4.5 dS m- 1 for lettuce, 9.4 dS m- I for the first crop of ryegrass and 0.4,7.5 & 15.0 dS m-1 for the second crop of ryegrass) and drained until an equilibrium soil water profile was attained. Water with the same electrical conductivity was then supplied by Marione siphons to maintain the constant water table. The water table contribution was recorded and water losses from the soil profile were estimated from daily readings of soil water potential using tensiometersa; nd gypsum blocks. Solute samples were extracted periodically for salinity measurement. The cropping period of lettuce was 90 days from sowing and the lst & 2nd cropping periods of ryegrass were 223 & 215 days respectively. The first ryegrass experiment showed that the water table depth (60,90 and 120 cm) did not have significant contribution (37,36 and 36 mm) on either total soil moisture use or groundwater contribution. Similar results were found for total soil moisture use for lettuce, though the groundwater contribution varied significantly. The second ryegrass experiment showed that salinity at the water table strongly influenced total soil moisture use, but the total groundwater contribution varied only slightly. The overall crop experiments show that the groundwater contribution was within the range of 25-30% of the total water use, except for the 15 dS m7l treatment where the contribution was greater than the soil moisture use. Groundwater contribution rate was higher when the plants were subjected to more osmotic and matric stresses. Yield component data show that increasing salinity leads to a reduction in total yield, but the drymatter proportion was higher. Higher salinities occurred in the upper 15 cm of the root zone, because of the greater soil moisture depletion. Below that depth the salinization rate was smaller, because of the greater groundwater contribution in the later part of the season. There is reasonable agreement between measured and estimated (based on convective transport theory) values soil salinity. Salinities increased in the root zone by about 3-fold of initial salinity for lettuce and around 4-fold for ryegrass in the top 5 cm depth, but below 15 cm depth it was less than 2 fold. Finally, a simplified model was developed to describe the interaction of root-zone salinity and water uptake, considering salinity and water stress as additive. The model shows that the higher the root-zone salinity stress, the higher the predicted water uptake while plant uptake considered -1.5 MPa. This variation is ranged from 4 to 17% for 0.4 to 9.4 dS m-1 and 30 % for 15 dS m-1. The model was developed in a climate with low atmospheric demand, but needs testing in a more severe environment.
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Barr, N. F. "Salinity control, water reform and structural adjustment : the Tragowel Plains Irrigation District /." Connect to thesis, 1999. http://eprints.unimelb.edu.au/archive/00000230/l.
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Molatakgosi, Goitsemodimo. "Impact of infield irrigation management by Botswana cabbage farmers on soil salinity." Thesis, Cranfield University, Cranfield University at Silsoe, 2005. http://hdl.handle.net/1826/1224.
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Some vegetable farmers in the semi- arid Botswana are struggling or closing down
their enterprises citing the cost of irrigation and salty water as the problem.
Irrigation with water from the salt-laden underground water is known to be the main
sources of salts for arid and semi-arid agricultural land. Crops grown in saline
environments show symptoms similar to those shown by drought-affected crops
hence more irrigation is needed therefore increasing the irrigation cost. Research
from other semi arid areas shows that water with high salinity levels can be used for
irrigation without increasing soil salinity to values beyond critical levels. A lot of
studies have been done which show that the impacts of saline irrigation water
depend on the irrigation management. This study therefore aims at recommending
infield irrigation management practices to be used by cabbage farmers in Botswana
without increase in soil salinity to levels that will affect crop yield.
A survey was conducted to identify the infield irrigation management practices
presently used by cabbage farmers in Botswana. Rootzone salinity trend due to the
identified infield irrigation management was simulated for 20 years using WaSim
simulation model. Recommendations on irrigation management practices were made
for those soil salinity trends that reached critical levels.
It was realised that there are no common infield irrigation management used by
farmers. The way farmers manage infield irrigation could not be identified with the
factors involved in irrigation scheduling. Infield irrigation management by the
farmers contribute to the soil salinity increase in their fields and some of the farmers are already using saline soils. Most farmers are not aware of the saline conditions they are farming on and those who know do not know about the soil salinity measures. The study recommends a need to educate farmers on irrigation under
saline environments and also a need for farmers to include soil salinity control in
their irrigation planning.
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Asghar, Muhammad Nadeem. "Computer simulation of salinity control by means of an evaporative sink." Thesis, University of Newcastle Upon Tyne, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.318173.
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Silva, Alexsandro Oliveira da [UNESP]. "Fertirrigação e controle da salinidade no cultivo de beterraba em ambiente protegido." Universidade Estadual Paulista (UNESP), 2012. http://hdl.handle.net/11449/93813.
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silva_ao_me_botfca.pdf: 2497584 bytes, checksum: acd2b658d1dbff5be344d07027c33e34 (MD5)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Universidade Estadual Paulista (UNESP)
O uso em execesso de fertilizantes em cultivo sobre ambiente protegido pode levar à salinização, e esse processo pode ser monitorado pela condutividade elétrica na solução do solo. O presente trabalho foi realizado com o objetivo de avaliar a utilização de extratores em cápsulas porosas no manejo da fertirrigação e no controle do processo de salinização em cultivo de beterraba (Beta vulgaris L.). Duas cultivares de beterraba (Early Wonder Tall Top e Itapuã) foram avaliadas em função de dois manejos de fertirrigação, sendo o primeiro o manejo tradicional utilizado pelos produtores rurais e o segundo com uso de extratores de solução do solo para controle da salinidade. O experimento foi realizado em vasos de 14 L e salinizados artificialmente a diferentes níveis de condutividade elétrica no extrato de saturação (1,0; 3,0; 6,0; 9,0; 12,0; dSm-1). Os resultados obtidos demonstram que o controle através de extratores em cápsulas porosas é eficiente no monitoramento de solos com problemas de salinização. Observou-se também que o controle da solução do solo em níveis de condutividade elétrica desejados, proporcionou um efeito benéfico no cultivo da beterraba evitando desequilíbrios iônicos e salinização do solo. O cultivo em ambiente protegido proporcionou menor consumo hídrico e coeficiente de cultivo do que os citados na literatura para cultivo convencional. Os manejos da fertirrigação utilizados proporcionaram efeitos significativos nas variáveis relacionadas ao crescimento e produtividade da...
The excessive use of fertilizers in farming on protected environment can lead to salinization, and this process can be monitored by electrical conductivity in the soil solution. The present study was carried out to evaluate the extraction of soil solution by porous cups, which were used with the purpose to manage the fertigation and control the salinization in beet crop (Beta vulgaris L.) Two beet cultivars (Early Wonder Tall Top and Itapuã) were evaluated against two fertigation managements, the first being the traditional management used by farmers and the second with the use of soil solution extractors to control salinity. The experiment was carried out in 14 L pots and artificially salinized with different levels of electrical conductivity in the saturation extract (1.0, 3.0, 6.0, 9.0, 12.0, dS m-1). The results obtained show that control through porous cup extractors is effective in monitoring soil salinization problems. It was also observed that control of soil solution at desired levels of electrical conductivity, provided a beneficial effect in the beet cultivation avoiding ionic imbalance and salinization. The protected cultivation resulted in less water consumption and crop coefficient than those reported in the literature for conventional farming. The fertigation managements used offered significant effects on variables related to the growth and yield of beet, possibly due to increased fertilizer which increased soil salinity and caused nutrient imbalances in plants. The relative yield of the trees showed a drop from the salinity threshold... (Complete abstract click electronic access below)
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Silva, Alexsandro Oliveira da 1985. "Fertirrigação e controle da salinidade no cultivo de beterraba em ambiente protegido /." Botucatu : [s.n.], 2012. http://hdl.handle.net/11449/93813.
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Orientador: Antônio Evaldo KlarCoorientador: Ênio Farias de França e Silva
Banca: Hélio Grassi Filho
Banca: Tales Miler Soares
Resumo: O uso em execesso de fertilizantes em cultivo sobre ambiente protegido pode levar à salinização, e esse processo pode ser monitorado pela condutividade elétrica na solução do solo. O presente trabalho foi realizado com o objetivo de avaliar a utilização de extratores em cápsulas porosas no manejo da fertirrigação e no controle do processo de salinização em cultivo de beterraba (Beta vulgaris L.). Duas cultivares de beterraba (Early Wonder Tall Top e Itapuã) foram avaliadas em função de dois manejos de fertirrigação, sendo o primeiro o manejo tradicional utilizado pelos produtores rurais e o segundo com uso de extratores de solução do solo para controle da salinidade. O experimento foi realizado em vasos de 14 L e salinizados artificialmente a diferentes níveis de condutividade elétrica no extrato de saturação (1,0; 3,0; 6,0; 9,0; 12,0; dSm-1). Os resultados obtidos demonstram que o controle através de extratores em cápsulas porosas é eficiente no monitoramento de solos com problemas de salinização. Observou-se também que o controle da solução do solo em níveis de condutividade elétrica desejados, proporcionou um efeito benéfico no cultivo da beterraba evitando desequilíbrios iônicos e salinização do solo. O cultivo em ambiente protegido proporcionou menor consumo hídrico e coeficiente de cultivo do que os citados na literatura para cultivo convencional. Os manejos da fertirrigação utilizados proporcionaram efeitos significativos nas variáveis relacionadas ao crescimento e produtividade da ... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The excessive use of fertilizers in farming on protected environment can lead to salinization, and this process can be monitored by electrical conductivity in the soil solution. The present study was carried out to evaluate the extraction of soil solution by porous cups, which were used with the purpose to manage the fertigation and control the salinization in beet crop (Beta vulgaris L.) Two beet cultivars (Early Wonder Tall Top and Itapuã) were evaluated against two fertigation managements, the first being the traditional management used by farmers and the second with the use of soil solution extractors to control salinity. The experiment was carried out in 14 L pots and artificially salinized with different levels of electrical conductivity in the saturation extract (1.0, 3.0, 6.0, 9.0, 12.0, dS m-1). The results obtained show that control through porous cup extractors is effective in monitoring soil salinization problems. It was also observed that control of soil solution at desired levels of electrical conductivity, provided a beneficial effect in the beet cultivation avoiding ionic imbalance and salinization. The protected cultivation resulted in less water consumption and crop coefficient than those reported in the literature for conventional farming. The fertigation managements used offered significant effects on variables related to the growth and yield of beet, possibly due to increased fertilizer which increased soil salinity and caused nutrient imbalances in plants. The relative yield of the trees showed a drop from the salinity threshold... (Complete abstract click electronic access below)
Mestre
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Wang, Sheng. "Turfgrass Responses and Rootzone Media Characteristics as Affected by Salinity." Thesis, North Dakota State University, 2011. https://hdl.handle.net/10365/28883.
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Utilization of salt-tolerant species or cultivars is one the most effective methods to address salinity problems in turfgrass management. The relative salt tolerance in 26 commercial creeping bentgrass (Agrostis stolonifera) cultivars during germination was studied. Final germination rate (FGR) and daily germination rate (DGR) decreased as salinity levels increased; however, DGR was more sensitive to salinity stress. Substantial differences in salt tolerance were observed in bentgrass cultivars, with 'Declaration', 'Seaside II', 'T-1 ', and 'Bengal' being the most salt-tolerant (averaged predicted salinity level causing 50% reduction of DGR [PSLD] = 8.2 g L -1 NaCl) and 'Tyee', 'Kingpin'. and 'SRI 150' being the most salt-sensitive (averaged PLSD = 6.5 g L -1 NaCl). Relative salinity tolerance in four populations of prairie junegrass (Koeleriu macrantha) collected from Colorado, Minnesota, Nebraska, and North Dakota and two improved turf-type cultivars from Europe ('Barleria' and 'Barkoel') was determined and compared to Kentucky bluegrass (Poa pratensis), perennial ryegrass (Lolium perenne), sheep fescue (Festuca ovina), hard fescue (F. brevipila), and tall fescue (F. arundinacea). All populations of prairie junegrass showed similar salt tolerance with an average of PSLF and PSLD being 7.1 and 5.3 g L -1 NaCl, respectively, comparable to Kentucky bluegrass and hard and sheep fescue but lower than tall fescue and perennial rye grass. In junegrasses, larger variations were observed in visual quality (VQ) than in electrolyte leakage (EL) and dry weight (OW) at vegetative growth stage. 'Barleria' junegrass showed the highest VQ, following two salt-tolerant grasses, tall fescue and sheep fescue. Junegrass - Nebraska population was the least salt-tolerant within the species, but still exhibited similar or higher tolerance than Kentucky bluegrass and perennial ryegrass cv. Arctic Green. Overall, junegrass was more salt sensitive during germination but more tolerant to salinity when mature.
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Ghamarnia, Houshang. "Effects of salinity on water extraction by roots under shallow groundwater table conditions." Thesis, University of Newcastle Upon Tyne, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.364808.
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Saleh, Said Abdel-Halim Abdel-Aty. "Physiological responses of artichoke plants to irrigation and fertilization under special recognition of salinity." [S.l. : s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=969853416.
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Walworth, James, and Thomas L. Thompson. "Salinity Management and Soil Amendments for Southwestern Pecan Orchards." College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2006. http://hdl.handle.net/10150/146654.
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Walworth, J. L. "Salinity Management and Soil Amendments for Southwestern Pecan Orchards." College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2011. http://hdl.handle.net/10150/239609.
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Brown, Paul. "Evaluation of ADWR Water Duties for Large Turf Facilities." College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2006. http://hdl.handle.net/10150/147021.
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14 pp.This publication summarizes the results of a three year research study that evaluated whether the turf water duties mandated by the Arizona Department of Water Resources provide adequate water to grow acceptable quality turf in the Tucson and Phoenix areas.
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Nava, Leon Jose Angel 1956. "CHLORIDE AND NITRATE DISTRIBUTION IN THE SOIL WITH FURROW AND BURIED DRIP IRRIGATION (SALINITY, SANDY LOAM)." Thesis, The University of Arizona, 1986. http://hdl.handle.net/10150/276671.
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Januarisya, Atika R. "Sodium impacts of three Queensland soils under CSG water irrigation." Thesis, Queensland University of Technology, 2016. https://eprints.qut.edu.au/97995/1/Atika_Januarisya_Thesis.pdf.
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This thesis contributes to identifying the importance of studying the specific nature of soils pertaining to soil impacts subjected to irrigation with coal seam gas water. Focusing on the sodium impact, changes in soil behaviour as well as the sodium adsorption potential of three Queensland soils were observed and analysed. In doing so, it was found that beneficial reuse of CSG water can be used on agricultural land provided irrigation is carefully managed.
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Ado, Maman Nassirou. "Evaluation in situ et en conditions contrôlées de la phytodésalinisation des Vertisols irrigués. Cas d’étude du périmètre rizicole de Kollo (Niger) dans la vallée du fleuve Niger." Thesis, Rennes, Agrocampus Ouest, 2017. http://www.theses.fr/2017NSARD082/document.
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L’objectif général de ce travail est de comprendre et d’évaluer le rôle des cultures, à fort développement racinaire et susceptibles de se développer en milieu salin et saturé, sur le processus de phytodésalinisation des Vertisols. L’étude est réalisée sur le périmètre irrigué de Kollo (Niger) dans la vallée du fleuve Niger et couple deux expérimentations : i) la première in situ teste la capacité de Echinochloa stagnina à dessaler les Vertisols durant 15 mois en comparaison avec le riz (Oriza sativa) et le sol nu submergé et ii) la deuxième, au laboratoire sur des colonnes du sol, étudie l’effet de E. stagnina sur les propriétés hydro-structurales des Vertisols durant 11 mois et vise à analyser et modéliser le processus de la phytodésalinisation des VertisolsLes résultats montrent que la porosité du sol croît progressivement sur le sol cultivé avec E. stagnina. La macroporosité totale est plus élevée sur le sol cultivé avec E. stagnina (6 à 10 %) que sur le sol nu (2 à 4 %). La salinité des Vertisols décroît significativement avec le temps du développement des cultures. A la fin de l’expérimentation in situ, le stock des sels dans la couche 0-60 cm a baissé de 33 à 36 % sous E. stagnina et seulement de 3 % pour le riz et le sol nu submergé. Au laboratoire, le stock des sels initial a baissé de 65 à 87 % sous E. stagnina et de 34 à 45 % sur le sol nu submergé. Il est nécessaire de comprendre davantage l’interaction entre les différents processus (fissuration, salinité, géochimie) intervenants pendant la période d’inter-cultureThe general objective of this study was to understand and to evaluate the role of crops, characterized by heavy root development and susceptible to growth in saline and flooded conditions, on phytodesalinization process of Vertisols.The study was conducted in the irrigated perimeter of Kollo (Niger) in Niger River valley and coupled two experimental approaches: i) a field study to test the capacity of Echinochloa stagnina to reclaim Vertisols salinity during 15 months in comparison with rice (Oriza sativa) and ponded bare soil and ii) a laboratory experimentation on soil columns to study the effect of E. stagnina roots on hydro-structural properties of Vertisols during 11 months and aims to analyze and modelling phytodesalinization processes of VertisolsThe results showed that the soil porosity progressively increased under soil cultivated with E. stagnina. The soil macroporosity was higher on soil cultivated with E. stagnina (6-10%) than bare soil (2-4%). The soil salinity of Vertisols significantly decreased with time of crop development. At the end of field study, the initial salt stock of 0-60 cm layer decreased by 33 to 36% under the E. stagnina crop and only by 3% under rice crop and ponded bare soil. In laboratory study, initial salt stock decreased by 65 to 87% under soil cultivated with E. stagnina and by 34 to 45% under ponded bare soil. It is necessary to understand the interactions between the different processes (cracking, salinity, and geochemistry) involved during the intercropping season
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BHATTARAI, SURYA PRASAD, and s. bhattarai@cqu edu au. "THE PHYSIOLOGY OF WATER USE EFFICIENCY OF CROPS SUBJECTED TO SUBSURFACE DRIP IRRIGATION, OXYGATION AND SALINITY IN A HEAVY CLAY SOIL." Central Queensland University. Biological and Environmental Sciences, 2005. http://library-resources.cqu.edu.au./thesis/adt-QCQU/public/adt-QCQU20050903.222650.
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Aza-Gnandji, Cocou Davis Ruben. "Salinity of irrigation water in the Philippi farming area of the cape flats, Cape Town, South Africa." University of the Western Cape, 2011. http://hdl.handle.net/11394/2921.
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Magister Scientiae - MScThis research investigated the nature, source and the spatial variation of the salinity of the water used for irrigation in the urban farming area of Philippi, which lies in the Cape Flats region of the Cape Town Metropolitan Area, South Africa. The irrigation water is mainly drawn from the Cape Flats aquifer, and pumped into ponds for eventual crop irrigation. Water samples were collected in summer and in winter from fifteen selected sites using standard water sampling procedures. Each site consisted of one borehole and one pond. The samples were routinely analyzed for salinity levels, and concentrations of major and minor ions. From the same boreholes and ponds, water was sampled in summer for isotope analysis to assess effects of evaporation on the water quality and salinity. Descriptive statistics were used to display the variation in range of specific ions in order to compare them with the recommended ranges. Geographical Information Systems analysis described the spatial distribution of the salinity across the study area, and hydrogeochemical analysis characterized the various waters and detected similarities between the water samples in the study area and other waters found in the Cape Flats region. In addition, the US salinity diagram classification of irrigation water developed by Richards (1954) was used to assess the current suitability of groundwater and pond water samples collected during the entire sampling period for irrigation activities. The research indicated that the concentrations of some ions such as chloride, nitrate, potassium and sodium exceeded in places in the study area, the target range values set by the Department of Water Affairs and Forestry (DWAF, 1996) and the Food and Agriculture Organization (Ayers and Westcot, 1985). It revealed that borehole and pond water were mostly brackish across the area regarding their total dissolved salts content, and fresh water was only found in the middle part of the study area. The research found that sea water does not intrude into the aquifer of the study area, and the accumulation of salts in groundwater and soil in the study area is mainly due to the agricultural activities and partially due to the natural movement of water through the geological formation of the Cape Flats region. The conceptual model of the occurrence of the salinization process supported these findings. From this investigation it is understood that the groundwater and pond water in the study area were generally suitable for irrigation purposes but they have to be used with caution as the vegetables are classified as sensitive and moderately sensitive to salt according to DWAF Irrigation water guidelines (1996). The quality of these waters was mainly affected by the land use activities.
South Africa
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Cunha, Cleyton Saialy Medeiros. "Relation between soil affected by salts and concentration of heavy metals in four in irrigation perimeters Ceara." Universidade Federal do CearÃ, 2013. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=13157.
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FundaÃÃo de Amparo à Pesquisa do Estado do CearÃAs pesquisas com salinizaÃÃo nos perÃmetros irrigados, quanto à presenÃa de metais pesados ainda sÃo incipientes. Estes metais vÃm sendo encontrados em Ãreas irrigadas e estÃo associados a grupos de impactos ambientais, por serem poluentes devido à sua toxicidade e persistÃncia no ambiente. O trabalho teve como objetivo verificar a concentraÃÃo de metais pesados e verificar as correlaÃÃes existentes entre eles em solos afetados por sais referentes a quatro (4) perÃmetros irrigados no Cearà (Baixo-acaraÃ; Morada Nova; Curu-Pentecoste e IcÃ-Lima Campos). Foram coletadas amostras de solo nas profundidades de 0â10 e 10-20 cm em 10 pontos dentro de cada perÃmetro, sendo (1) ponto, dentro de cada perÃmetro, referente a solos de vegetaÃÃo preservada, totalizando oitenta (80) amostras. Foram obtidos os teores pseudototais de metais, assim como foram realizadas anÃlises multivariadas (anÃlise de correlaÃÃo canÃnica e fatorial), entre atributos relacionados com a salinizaÃÃo (CTC, PST, pH e CE) e variÃveis constituÃdas pelos metais pesados (Al, B, Mn, Mo, Si, Zr, Cr, Fe, V, Ni, Pb, Ti, Zn, As, Cd, Co e Cu) na camada de 0-10 e 10-20. Concluiu-se que: a) Os teores de metais pesados e elementos nos solos dos quatro perÃmetros seguiram a seguinte ordem decrescente: Fe, Al, Si, Ti, Mn, Zn, Cr, V, Ni, Cu, Co, B, Pb, Se, Cd, Mo, Zr, sendo esta ordem, no geral, independente das camadas superficiais e subsuperficiais consideradas. b) Os valores de referÃncia de qualidade para metais pesados e elementos obtidos neste estudo, de modo geral, foram considerados baixos, quando comparados com os valores estipulados por ÃrgÃos ambientais (CONAMA e CETESB). Inclusive, para todas as amostras de solo, os teores de As e Hg, ficaram abaixo de limite de detecÃÃo do aparelho (0,01). c) Os atributos do solo relacionadas com a salinizaÃÃo CTC, pH, PST e CE contribuÃram para explicar os teores de metais pesados nos solos dos quatro perÃmetros irrigados, quando analisados em conjunto; todavia, nÃo foram capazes de explicar quando analisados de forma individual; seguindo a ordem de importÃncia: CTC > pH > PST > CE. d) Foram verificadas correlaÃÃes entre os elementos metÃlicos analisados neste estudo (B, Mo, Si, Zr, Cr, Ni, Pb, Ti, Zn, Cd, Co, Se e Cu) com o Fe, Mn, Al, Ti e V, ou, ainda, afinidades geoquÃmicas entre os elementos, nos solos dos quatro perÃmetros irrigados do CearÃ.
Researches with salinization in irrigated areas, for the presence of heavy metals are still incipient. These metals have been consistently found in areas irrigated groups and are associated with environmental impact, being pollutants because of their toxicity and persistence in the environment. The study aimed to determine the concentration of heavy metals and to establish correlations between them in salt affected soils less than four (4) in irrigated Cearà (Baixo-AcaraÃ; Morada Nova; Curu-Pentecost and Ico-Lima Campos). Samples were collected at depth of 0-10 and 10-20 cm in 10 points within each perimeter, being (1) point within each perimeter, referring to soils preserved vegetation, totaling (80) samples. Were obtained the total contents of metals, as well as multivariate analyzes were performed (canonical correlation analysis and factorial) between attributes related to salinization (pH, CE, CTC and PST) and variable consisting of the heavy metals (Al, B, Mn , Mo, Si, Zr, Cr, Fe, V, Ni, Pb, Ti, Zn, As, Cd, Co and Cu) in the 0-20 cm. It was concluded that: a) The levels of heavy metals and elements in soils of the four perimeters followed the following order: Fe, Al, Si, Ti, Mn, Zn, Cr, V, Ni, Cu, Co, B, Pb , Se, Cd, Mo, Zr, and this order, in general, independent of the surface and subsurface layers considered. b) The reference values for heavy metals and quality data obtained in this study, in general, were low compared to the values stipulated by environmental agencies at Brasil (CONAMA and CETESB). In fact, for all the soil samples, the levels of As and Hg were below the limit of detection apparatus (0.01). c) Soil attributes related to salinity CTC, pH, EC and PST contributed to explain the levels of heavy metals in soils of the four irrigation schemes, when analyzed together, however, were not able to explain when analyzed individually. Following the order of importance: CTCT > pH > PST > EC. d) Correlations were observed between metallic elements analyzed in this study (B, Mo, Si, Zr, Cr, Ni, Pb, Ti, Zn, Cd, Co, Se and Cu) with Fe, Mn, Al, Ti and V, or even, geochemical affinities between the elements in the four soils irrigated CearÃ.
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Samak, Abdel-Lateif Abdel-Wahab [Verfasser]. "Soil moisture, crop yield and soil salinity relocation under partial rootzone drying irrigation / Abdel-Lateif Abdel-Wahab Samak." Hannover : Technische Informationsbibliothek und Universitätsbibliothek Hannover (TIB), 2012. http://d-nb.info/1024386198/34.
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Beletse, Yacob Ghebretinsae. "The environmental impact and sustainability of irrigation with coal-mine water." Thesis, University of Pretoria, 2009. http://hdl.handle.net/2263/24935.
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The environmental impact and sustainability of irrigation with coal-mine water was investigated from an agricultural point of view on different coal-mines in the Republic of South Africa. Field trials were carried out on a commercial and plot scale, on sites that could offer a range of soil, crop, weather conditions and water qualities such as gypsiferous, sodium sulphate and sodium bicarbonate waters. Crop production under irrigation with gypsiferous mine water is feasible on a field scale and sustainable if properly managed. No symptoms of foliar injury due to centre pivot sprinkler irrigation with gypsiferous water were observed. The presence of high Ca and Mg in the water suppressed plant uptake of K. This could be corrected by regular application of K containing fertilizers. The bigger problem experienced was waterlogging due to poor site selection, especially during the summer months. The problem is not related to the chemistry of the gypsiferous water used for irrigation. Pasture production with Na2SO4 rich mine effluent was also feasible, at least in the short term, but would need a well-drained profile and large leaching fraction to prevent salt build up. Forage quality was not affected by the Na2SO4 water used. NaHCO3 water was of very poor quality for irrigation and is not recommended for irrigation. Salt tolerant crops that are not susceptible to leaf scorching can be produced with this water, but only with very high leaching fractions and careful crop management. Regular gypsum application will be required to prevent structural collapse of the soil. Most of the salts applied will leach from the soil profile, and will probably need to be intercepted for treatment or reuse. The Soil Water Balance (SWB) model was validated successfully. The model predicted crop growth, soil water deficit to field capacity and soil chemistry reasonably well, with simulated results quite close to measured values. Soluble salts have to be leached from the soil profile, so that crop production can be sustainable, but will externalize the problem to the receiving water environment. To assess the environmental impact of irrigation with coal-mine water, it is valuable to develop a tool that can assist with prediction of offsite effects. SWB was validated for runoff quantity and quality estimations, and was found to give reasonable estimates of runoff quantity and quality. SWB also predicted the soil water and salt balance reasonably well. This gives one confidence in the ability of the model to simulate the soil water and salt balance for long-term scenarios and link the output of SWB to ground and surface water models to predict the wider impact of large scale irrigation. This will also link the findings of this work to other research oriented towards the management of mine water and salt balances on a catchment scale. It will also help authorities make informed decisions about the desirability and consequences of permitting mine water irrigation on a large scale. Irrigation with gypsiferous mine water can be part of finding the solution to surplus mine water problems. Appropriate irrigation management of mine water is essential for the long-term sustainability of irrigation.Thesis (PhD)--University of Pretoria, 2009.
Plant Production and Soil Science
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Barros, JosivÃnia Rodrigues. "Irrigation yellow melon plants with saline water enriched with CO2." Universidade Federal do CearÃ, 2015. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=14644.
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Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgicoSalt excess in the soil solution is a serious problem in agriculture, caused mainly by irrigation water, causing soil salinization. These salts, when absorbed affects the growth of plants because of the osmotic effect, reducing the absorption of water in the soil. In order to mitigate the deleterious effects of these salts in plants, several strategies have been developed in order to make plants most tolerant to salt stress. A recent innovation in plant cultivation system is the enrichment of irrigation water with carbon dioxide (carbonation), influencing the commercial crop yield and making them more tolerant to stresses. The objective of this study was to evaluate whether the application of CO2 in irrigation water of melon plants increases the tolerance of the same to salt stress. The experiment was conducted in Pacajus Experimental Field of Embrapa Tropical Agroindustry. The treatments were arranged in a factorial 5 x 3 with four replications, referring to salt solutions at electrical conductivities of (ECw) (0.5, 1.5, 3.0, 4.5 and 6.0 dS m-1) and three treatments with CO2: no CO2 (SC), five applications of CO2 (since flowering until the beginning ripening of fruits) (C1) and two applications of CO2 (since fruit set until the ripening of fruits) (C2). The CO2 was used as a gas injected weekly directly in the irrigation system. The electrical conductivity of the soil saturation extract and CO2 content in the irrigation water were measured at the end of the experiment. The measurement of photosynthesis, stomatal conductance and transpiration occurred throughout plant development. Were also evaluated leaf area, dry weight of leaves and stem + branches, levels of Na+, Cl-, K+ and carbohydrates in the leaves and stems + branches, the number of fruits, productivity, weight, lengths and diameters of the fruit, pulp thickness, total soluble solids and citric acid content. Leaf concentrations of Na+, Cl- and K+ in the leaf and stem + branches were influenced by salinity, with interaction salinity x CO2. For the growth variables: leaf area, dry matter of leaves and stem + branches, there was a significant difference only for the salinity levels. All variables of gas exchange were influenced by salinity, while the stomatal conductance and net photosynthesis were significantly influenced by the application of CO2. The carbohydrate in stem + branches were influenced by the application of CO2. Irrigation with saline water caused a reduction in productivity, number of fruits, lengths of commercial and total fruits. These variables were not influenced by the application of CO2. It is concluded that salinity affected the growth, development and production of melon plants, while the application of CO2 did not minimize the deleterious effect of salts in plants.
Um dos grandes problemas enfrentados pela agricultura à o excesso de sais dissolvidos na soluÃÃo do solo, carreados principalmente pela Ãgua de irrigaÃÃo, causando a salinizaÃÃo do solo. Esses sais, ao serem absorvidos, afetam o crescimento das plantas devido ao efeito osmÃtico, dificultando a absorÃÃo de Ãgua no solo. A fim de amenizar os efeitos deletÃrios desses sais nas plantas, vÃrias estratÃgias vÃm sendo desenvolvidas visando tornar as plantas mais tolerantes ao estresse salino. Uma inovaÃÃo recente no sistema de cultivo de plantas à o enriquecimento da Ãgua de irrigaÃÃo com o diÃxido de carbono (carbonataÃÃo), influenciando a produtividade comercial da cultura e tornando-a mais tolerante a estresses. Assim, o objetivo deste trabalho foi avaliar se a aplicaÃÃo de CO2 na Ãgua de irrigaÃÃo de plantas de meloeiro aumenta a tolerÃncia das mesmas ao estresse salino. O experimento foi conduzido no Campo Experimental de Pacajus da Embrapa AgroindÃstria Tropical. Os tratamentos foram dispostos em esquema fatorial 5 x 3 com quatro repetiÃÃes, referentes Ãs soluÃÃes salinas com condutividades elÃtricas de (CEa) (0,5; 1,5; 3,0; 4,5 e 6,0 dS m-1) e trÃs tratamentos de CO2: ausÃncia de CO2 (SC), cinco aplicaÃÃes de CO2 (inÃcio do florescimento atà a maturaÃÃo dos frutos) (C1) e duas aplicaÃÃes de CO2 (apÃs a frutificaÃÃo atà a maturaÃÃo dos frutos) (C2). O CO2 foi aplicado na forma de gÃs, injetado semanalmente diretamente no sistema de irrigaÃÃo. A condutividade elÃtrica do extrato de saturaÃÃo do solo e o teor de CO2 na Ãgua de irrigaÃÃo foram mensurados ao final do experimento. As mediÃÃes de fotossÃntese, transpiraÃÃo e condutÃncia estomÃtica ocorreram ao longo do desenvolvimento das plantas. Foram avaliadas ainda a Ãrea foliar, as massas secas das folhas e do caule + ramos, os teores de Na+, Cl-, K+ e os carboidratos nas folhas e nos caules + ramos, o nÃmero de frutos, a produtividade de frutos, o peso, os comprimentos e diÃmetros dos frutos, espessura da polpa, sÃlidos solÃveis totais e teor de Ãcido cÃtrico. Os teores de Na+, Cl- e k+ na folha e caule + ramos foram influenciados pela salinidade, havendo interaÃÃo salinidade x CO2. Para as variÃveis de crescimento: Ãrea foliar, matÃria seca das folhas e caule +ramos, houve diferenÃa significativa apenas para os nÃveis de salinidade. Todas as variÃveis de trocas gasosas foram influenciadas pela salinidade, enquanto que a condutÃncia estomÃtica e a fotossÃntese liquida foram significativamente influenciadas pela aplicaÃÃo de CO2. Os teores de carboidratos no caule + ramos foram influenciados pela aplicaÃÃo de CO2. A irrigaÃÃo com Ãgua salina provocou reduÃÃo na produtividade, nÃmero de frutos, comprimentos dos frutos comercias e mÃdios. Essas variÃveis nÃo foram influenciadas pela aplicaÃÃo de CO2. Em funÃÃo do exposto, conclui-se que a salinidade afetou o crescimento, desenvolvimento e produÃÃo das plantas de meloeiro, enquanto a aplicaÃÃo do CO2 nÃo minimizou o efeito deletÃrio dos sais nas plantas.
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Barros, Adilson David de [UNESP]. "Manejo da irrigação por gotejamento, com diferentes níveis de salinidade da água, na cultura do melão." Universidade Estadual Paulista (UNESP), 2002. http://hdl.handle.net/11449/103456.
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barros_ad_dr_botfca.pdf: 997487 bytes, checksum: 9034f8d0dbf76fa3cf82f44f9c95ee54 (MD5)A produção de melão vem se tornando cada vez mais tecnificada, principalmente para a região semi-árida nordestina. Este interesse de tentar cada vez mais melhorar as condições de manejo da cultura faz com que os produtores tenham a cada dia, uma produção de qualidade. Existem alguns fatores que podem interferir nestas buscas de aperfeiçoamento das técnicas de manejo, como, por exemplo, as exigências do manejo hídrico na cultura. Por outro lado, a maior demanda por água tem levado a uma diminuição da maioria das fontes de água de boa qualidade disponíveis na região, obrigando a utilização de água com diferentes níveis de salinidade. Partindo-se desses fatores, o presente trabalho teve como objetivo estudar os efeitos de diferentes níveis de salinidade da água, freqüência e lâminas de irrigação em alguns cultivares de melão, ora destacando-se como promissoras para o mercado consumidor nacional e internacional, como também avaliar o processo de salinização do solo. Para isso, conduziram-se dois experimentos consecutivos em campo, numa mesma área, medindo 0,19 ha. No primeiro estudou-se o efeito de três níveis salinos (CE de 1,1; 2,6 e 3,9 dS.m-1), duas lâminas de irrigação (1,1ETm e 1,25ETm) e duas freqüências de irrigação (diária e 2 dias) utilizando a cultivar de melão amarelo Gold mine. No segundo experimento utilizaram-se três níveis salinos (CE de 1,1; 2,5 e 4,5 dS.m-1), duas freqüências de irrigação (diária e 2 dias) e duas cultivares de melão cantaloupe (Trusty e Orange Flesh). O experimento foi composto de quatro blocos ao acaso, cada um dividido em doze parcelas tratamento medindo 6 m x 6 m, irrigadas por gotejamento. O resultado do primeiro experimento apresentou que o processo de salinização do solo ocorreu durante o ciclo da cultura, diminuindo significativamente no período das chuvas que correspondeu...
The melon production, particularily in the semi-arid region of Northeast of Brazil, is becoming highly technological. The interest to improve crop management conditions is to provide melon produces opportunity to obtain better quality production. The are, however, some factors which may interfer in further improvement of management techniques, for exemple needs of water management of the crop. On the other hand, the increased demand of water has decreased availability of good quality water sources in the region, thereby, oblising use of water of different salinities. Keeping this in view, the present study had the objective of verifying the effects of water of different salinities, frequency and irrigation depths in some promising melon cultivars for the national and international consumer market, as well as to evaluate process of salinization. For this, two consecutive field experiments were conducted in a same area of 0,19 ha. In the first trial the effets of three salinity levels (electrical conductivity - ECw of 1.1, 2.6 and 3.9 dS.m-1), two irrigation depths (1.1Etm and 1.25ETm) and two frequency of irrigation (daily and every two days) were studied utilizing Yellow Gold Mine melon cultivar. In the second experiment the salinity levels (Ecw of 1.1, 2.5 and 4.5 dS.m-1), two frequency of irrigation (daily and at interval of two days) and two cultivars (Trusty and Orange Flesh) of cantaloup melon were studied. The experiment consisted of four randomized blocks, each one divided into 12 drip irrigated treatment plots of 6 x 6 m. The result of first experiment revealed that the soil salinization occurred during the crop cycle but decreased appreciably during the rainy period which corresponded to interval between two crop cycles. The regression equations which correlated the EC1:2 and ECse in 0-30 cm depth foun were... (Complete abstract click electronic access below)
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Silva, Weslley Costa. "Answers of cowpea to different irrigation with water saline and doses biofertilizer." Universidade Federal do CearÃ, 2016. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=17328.
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nÃo hÃThe objective of this study was to evaluate the responses of cowpea (Vigna Unguicullata L. Walp) produced under the effect of different irrigation with saline water and liquid biofertilizer doses. Held this experiment in an experimental area Federal Institute of CearÃ, located in the municipality of Umirim - CE with the cultivar of cowpea âBRS Pujanteâ. The experiment obeyed in a randomized block, in a split plot, totaling sixteen treatments and four repetitions. The plot consisted application of four different irrigation water with saline water (75; 100; 125 and 150% of crop evapotranspiration - ETc) and the subplots consisted of four different biofertilizer doses (0; 60; 120 e 180ml/plant). To perform irrigation was using a system drip. The water utility is classified as C4S1 and has electrical conductivity 3.81 dS.m-1. The biofertilizer was prepared in aerobic system, using water and cattle manure in the proportions of 1:1. The doses used were divided in three applications, this being performed at 10, 40 and 70 days after sowing â DAS. To 15, 45 and 75 DAS, they were analyzed chlorophyll content A e B and gas exchange in plants of cowpea, and the end of the experiment the growth, productive components and grain yield per plant. The results were subjected to the analysis of variance by F and their means compared by test Tukey and regression analysis. The results showed significant interaction between factors, getting meaningful answers to 75 DAS for the chlorophyll A. For gas exchange dose 120ml / bio-fertilizer plant was the best interacted with the laminae to 15 and 45 DAS. To 75 DAS the water depth was significant, adjusting the linear model for photosynthesis and stomatal conductance and quadratic for the concentration internal CO2 and transpiration. For growth , the increase in water depth provided to increase dry matter and total leaf Ãrea, being observed respectively adding up 32,42 and 64%. The increase of biofertilizer dose provided increment the number of sheets , fitting the quadratic model and reaching peak on the dose of 80 ml/plant. The production of dry grains , the interaction between the factors was significant , with higher averages in the blades of 100% of ETc and reaching a production of 23.76 and 23.07 g under the doses of 0 and 60 ml/plant of biofertilizers, respectively. Thus the application of different irrigation responded significantly culture , observed higher values when applied blades above 100 % of the ETc. For biofertilizers its application did not respond significantly the variables analyzed.
O objetivo deste trabalho foi avaliar as respostas do feijÃo-caupi (Vigna Unguicullata L. Walp) produzido sob efeito de diferentes lÃminas de irrigaÃÃo com Ãgua salina e doses de biofertilizante lÃquido. Para isso realizou-se este experimento em uma Ãrea experimental do Instituto Federal do CearÃ, localizado no municÃpio de Umirim - CE com a cultivar de feijÃo-caupi âBRS Pujanteâ. O experimento obedeceu ao delineamento em blocos ao acaso, em parcelas subdivididas, totalizando dezesseis tratamentos e quatro repetiÃÃes. As parcelas consistiram na aplicaÃÃo de 4 diferentes lÃminas de irrigaÃÃo com Ãgua salina (75; 100; 125 e 150% da evapotranspiraÃÃo da cultura - ETc) e as subparcelas diferentes doses de biofertilizante bovino (0; 60; 120 e 180 ml/planta). Para realizaÃÃo da irrigaÃÃo foi utilizado um sistema por gotejamento. A Ãgua utilizada foi classificada como C4S1 e possui condutividade elÃtrica de 3,81 dS.m-1. O biofertilizante foi preparado em sistema aerÃbico, utilizando Ãgua e esterco bovino fresco nas proporÃÃes de 1:1. As doses utilizadas foram parceladas em trÃs aplicaÃÃes, sendo estas realizadas aos 10, 40 e 70 dias apÃs a semeadura â DAS. Aos 15, 45 e 75 DAS, foram analisados o Ãndice de clorofila A e B e trocas gasosas em plantas de feijÃo-caupi, e ao final do experimento o crescimento, os componentes produtivos e produÃÃo de grÃos por planta. Os resultados obtidos foram submetidos a anÃlise de variÃncia pelo teste F e feito o teste de Tukey e anÃlise de regressÃo. Os resultados demonstraram interaÃÃo significativa entre os fatores, obtendo respostas significativas aos 75 DAS para o Ãndice de clorofila A. Para as trocas gasosas, a dose 120 ml/planta de biofertilizante foi a que melhor interagiu com as lÃminas de irrigaÃÃo aos 15 e 45 DAS. Aos 75 DAS a lÃmina de irrigaÃÃo foi significativa, ajustando-se ao modelo linear para a fotossÃntese e condutÃncia estomÃtica e quadrÃtica para a concentraÃÃo de interna de CO2 e transpiraÃÃo. Para o crescimento, o aumento da lÃmina de irrigaÃÃo proporcionou aumento para a matÃria seca total e Ãrea foliar, sendo observado respectivamente, acrÃscimo de atà 32,42 e 64%. O aumento da dose de biofertilizante proporcionou incremento ao nÃmero de folhas, ajustando-se ao modelo quadrÃtico e atingindo ponto mÃximo sobre a dose de 80 ml/planta. Quanto a produÃÃo de grÃos secos, a interaÃÃo entre os fatores se mostrou significativa, apresentando maiores mÃdias sob a lÃminas de 100% da ETc e atingindo uma produÃÃo de 23,76 e 23,07 g sob as doses de 0 e 60 ml/planta de biofertilizante, respectivamente. Desta forma à aplicaÃÃo de diferentes lÃminas de irrigaÃÃo respondeu de forma significativa a cultura, sendo observados maiores valores quando aplicado lÃminas acima de 100% da ETc. Para o biofertilizante sua aplicaÃÃo nÃo respondeu de forma significativa as variÃveis analisadas.
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Filho, JoÃo Valdenor Pereira. "Irrigation strategies with waters of different salinity levels aimed at the sustainability of the cowpea cultivars in semi-arid production system." Universidade Federal do CearÃ, 2016. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=17260.
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CoordenaÃÃo de AperfeÃoamento de Pessoal de NÃvel SuperiorSalinity has constituted today one of the main problems facing irrigated agriculture. Failure to proper management of the practice of irrigation by farmers, associated the prevailing climatic conditions in arid and semi-arid regions has contributed to the accelerated process of salinization, thus leaving several inactive irrigated areas for agriculture. In this context, the work herein developed was to examine the propensity of different strategies for handling irrigation through the use of lower quality water in salinization and sodification soil, besides evaluating the morphological, physiological, biochemical and productive responses, cultivars cowpea beans, to obtain information about the better understanding of the processes involved in the responses of salt tolerance, and enable the election cultivars adapted irrigation with saline water conditions. The experiment was conducted in pots in the open, in the experimental area of the weather station of the Federal University of CearÃ, Fortaleza, CearÃ, under an experimental design of randomized blocks in split plots. The two water regimes (plots) were based on the potential crop evapotranspiration (100 and 50% of ETpc). Already irrigation water salinity levels (0.95; 2.45; 3.95; 5.45 and 6.95 dS m-1) were distributed in the subplots, while the cultivars (Epace 10 and BRS Itaim) in subsubplots. The increased concentration of salts in irrigation water reduced the plant height, number of leaves, dry weight of shoot and the pH of the soil solution, except for the electrical conductivity of the soil that kept adding to the imposition of different salt concentrations. Due to the absence of leaching, the treatments irrigated with a blade 50% of ETpc maintained higher values of soil electrical conductivity and potassium levels in the soil, providing reduction in leaf area. Through the morphological variables, the cultivar Epace 10 showed better performance than BRS Itaim. The physiological responses analyzed, it was found that the levels of chlorophyll pigments a, b, and total carotenoid contents of the well are reduced by increasing the salt concentration in the irrigation water. Under conditions of lower water availability (50% of ETpc), to cultivate Epace 10 was higher for the content of photosynthetic pigments. There was no significant change in parameters associated with the emission of fluorescence due to salt and water stress. In general, we observed reductions in the behavior of gas exchange under the rise in salinity levels, thereby enhancing the interdependence between the variables analyzed. On the productive potential and biochemical responses analyzed it was found that the concentration of salts in irrigation water provided greater accumulation of N-aminossolÃveis content, proline and Cl- in the bean cowpea leaves. Under a water system 50% of ETpc, the N-aminossolÃveis content and K+ are higher than the system 100% of ETpc. The cultivar Epace 10 has higher accumulations N-aminossolÃveis and Cl-, besides presenting more free proline accumulation, under a water system 50% of ETpc. The total yield potential of the cowpea is reduced by the addition of salts in the irrigation water. The cultivar Epace 10 showed greater tolerance imposed management conditions, making it more suitable growing conditions in regions subject to water stress and / or saline.
A salinidade tem se constituÃdo hoje num dos principais problemas enfrentados pela agricultura irrigada. A falta de manejo adequado da prÃtica de irrigaÃÃo pelos produtores, associado as condiÃÃes climÃticas reinantes em regiÃes Ãridas e semiÃridas tem contribuÃdo para o acelerado processo de salinizaÃÃo dos solos, deixando assim diversas Ãreas irrigadas inativas para a prÃtica agrÃcola. Neste contexto, o trabalho desenvolvido buscou analisar a propensÃo de diferentes estratÃgias de manejo da irrigaÃÃo, atravÃs da utilizaÃÃo de Ãguas de qualidades inferiores, em salinizar ou sodificar o solo, alÃm de avaliar as respostas morfolÃgicas, fisiolÃgicas, bioquÃmicas e produtivas, de cultivares de feijÃo caupi, visando obter informaÃÃes acerca do melhor entendimento dos processos envolvidos nas respostas de tolerÃncia à salinidade, alÃm de possibilitar a eleiÃÃo de cultivares adaptadas as condiÃÃes de irrigaÃÃo com Ãguas salinas. O experimento foi conduzido em vasos, a cÃu aberto, na Ãrea experimental da EstaÃÃo AgrometeorolÃgica da Universidade Federal do CearÃ, Fortaleza, CearÃ, sob um delineamento estatÃstico de blocos ao acaso em parcelas subsubdivididas. Os dois regimes hÃdricos (parcelas) foram baseados pela evapotranspiraÃÃo potencial da cultura (100 e 50% da ETpc). Jà os nÃveis de salinidade da Ãgua de irrigaÃÃo (0,95; 2,45; 3,95; 5,45 e 6,95 dS m-1) foram distribuÃdos nas subparcelas, enquanto as cultivares (Epace 10 e BRS Itaim) nas subsubparcelas. O aumento da concentraÃÃo de sais na Ãgua de irrigaÃÃo reduziu a altura das plantas, o nÃmero de folhas, a massa seca da parte aÃrea e o pH da soluÃÃo do solo, no entanto, proporcionou um aumento linear na condutividade elÃtrica do solo. Devido a ausÃncia de lixiviaÃÃo, os tratamentos irrigados com uma lÃmina de 50% da ETpc mantiveram valores superiores da condutividade elÃtrica e dos teores de potÃssio no solo, propiciando reduÃÃo na Ãrea foliar. AtravÃs das variÃveis morfolÃgicas estudadas, a cultivar Epace 10 demonstrou melhor desempenho que a cultivar BRS Itaim. Quanto as respostas fisiolÃgicas analisadas, constatou-se que, os teores dos pigmentos da clorofila a, b e total, alÃm dos teores de carotenoides sÃo reduzidos com o aumento da concentraÃÃo de sais na Ãgua de irrigaÃÃo. Sob condiÃÃes de menor disponibilidade hÃdrica (50% da ETpc), a cultivar Epace 10 apresentou valores superiores nos teores de pigmentos fotossintÃticos. NÃo se verificou alteraÃÃo significativa nos parÃmetros associados à emissÃo da fluorescÃncia, devida ao estresse salino e hÃdrico. De maneira geral, foi possÃvel observar reduÃÃes nas respostas das trocas gasosas sob o aumento dos nÃveis de salinidade, reforÃando assim, a interdependÃncia entre as variÃveis analisadas. Sobre o potencial produtivo e respostas bioquÃmicas analisadas verificou-se que o aumento da concentraÃÃo de sais na Ãgua de irrigaÃÃo propiciou maior acÃmulo dos teores de N-aminossolÃveis, prolina e Cl- nas folhas do feijoeiro caupi. Sob um regime hÃdrico de 50% da ETpc, os teores de N-aminossolÃveis e K+ sÃo superiores aos do regime de 100% da ETpc. A cultivar Epace 10 apresenta maiores acÃmulos N-aminossolÃveis e de Cl-, alÃm de apresentar maior acÃmulo de prolina livre, sob um regime hÃdrico de 50% da ETpc. O potencial produtivo total do feijÃo caupi à reduzido pelo acrÃscimo de sais na Ãgua de irrigaÃÃo. A cultivar Epace 10 apresentou maior tolerÃncia as condiÃÃes de manejo impostas, tornando-se mais adaptada as condiÃÃes de cultivo em regiÃes sujeitas a estresse hÃdrico e/ou salino.
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Barros, Adilson David de 1952. "Manejo da irrigação por gotejamento, com diferentes níveis de salinidade da água, na cultura do melão /." Botucatu : [s.n.], 2002. http://hdl.handle.net/11449/103456.
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Resumo: A produção de melão vem se tornando cada vez mais tecnificada, principalmente para a região semi-árida nordestina. Este interesse de tentar cada vez mais melhorar as condições de manejo da cultura faz com que os produtores tenham a cada dia, uma produção de qualidade. Existem alguns fatores que podem interferir nestas buscas de aperfeiçoamento das técnicas de manejo, como, por exemplo, as exigências do manejo hídrico na cultura. Por outro lado, a maior demanda por água tem levado a uma diminuição da maioria das fontes de água de boa qualidade disponíveis na região, obrigando a utilização de água com diferentes níveis de salinidade. Partindo-se desses fatores, o presente trabalho teve como objetivo estudar os efeitos de diferentes níveis de salinidade da água, freqüência e lâminas de irrigação em alguns cultivares de melão, ora destacando-se como promissoras para o mercado consumidor nacional e internacional, como também avaliar o processo de salinização do solo. Para isso, conduziram-se dois experimentos consecutivos em campo, numa mesma área, medindo 0,19 ha. No primeiro estudou-se o efeito de três níveis salinos (CE de 1,1; 2,6 e 3,9 dS.m-1), duas lâminas de irrigação (1,1ETm e 1,25ETm) e duas freqüências de irrigação (diária e 2 dias) utilizando a cultivar de melão amarelo Gold mine. No segundo experimento utilizaram-se três níveis salinos (CE de 1,1; 2,5 e 4,5 dS.m-1), duas freqüências de irrigação (diária e 2 dias) e duas cultivares de melão cantaloupe (Trusty e Orange Flesh). O experimento foi composto de quatro blocos ao acaso, cada um dividido em doze parcelas tratamento medindo 6 m x 6 m, irrigadas por gotejamento. O resultado do primeiro experimento apresentou que o processo de salinização do solo ocorreu durante o ciclo da cultura, diminuindo significativamente no período das chuvas que correspondeu... (Resumo completo, clicar acesso eletrônico abaixo)Abstract: The melon production, particularily in the semi-arid region of Northeast of Brazil, is becoming highly technological. The interest to improve crop management conditions is to provide melon produces opportunity to obtain better quality production. The are, however, some factors which may interfer in further improvement of management techniques, for exemple needs of water management of the crop. On the other hand, the increased demand of water has decreased availability of good quality water sources in the region, thereby, oblising use of water of different salinities. Keeping this in view, the present study had the objective of verifying the effects of water of different salinities, frequency and irrigation depths in some promising melon cultivars for the national and international consumer market, as well as to evaluate process of salinization. For this, two consecutive field experiments were conducted in a same area of 0,19 ha. In the first trial the effets of three salinity levels (electrical conductivity - ECw of 1.1, 2.6 and 3.9 dS.m-1), two irrigation depths (1.1Etm and 1.25ETm) and two frequency of irrigation (daily and every two days) were studied utilizing Yellow Gold Mine melon cultivar. In the second experiment the salinity levels (Ecw of 1.1, 2.5 and 4.5 dS.m-1), two frequency of irrigation (daily and at interval of two days) and two cultivars (Trusty and Orange Flesh) of cantaloup melon were studied. The experiment consisted of four randomized blocks, each one divided into 12 drip irrigated treatment plots of 6 x 6 m. The result of first experiment revealed that the soil salinization occurred during the crop cycle but decreased appreciably during the rainy period which corresponded to interval between two crop cycles. The regression equations which correlated the EC1:2 and ECse in 0-30 cm depth foun were... (Complete abstract click electronic access below)
Orientador: Antônio de Pádua Sousa
Coorientador: José Francismar de Medeiros
Banca: João Carlos Cury Saad
Banca: Raimundo Leite Cruz
Banca: José Renato Zanini
Banca: Tarlei Arriel Botrel
Doutor
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Clark, Louise Jayne. "Changes in properties of vineyard red brown earths under long - term drip irrigation, combined with varying water qualities and gypsum application rates." Title page, table of contents and summary only, 2004. http://hdl.handle.net/2440/37808.
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Irrigation water of poor quality can have deleterious effects on soils. However, the effect of drip irrigation on seasonal and long term (e.g. over 50 years) changes in soil chemical properties is poorly understood, complicated by the two-dimensional water flow patterns beneath drippers. Field and laboratory experiments were conducted, along with computer modelling, to evaluate morphological and physio-chemical changes in a typical Barossa Valley Red Brown Earth (Palexeralf, Chromosol or Lixisol) when drip irrigated under various changing management practices. This work focused on the following two management changes : (i) switching from long-term irrigation with a saline source to less saline water and (ii) gypsum (CaSO₄) application. A literature review (Chapter 1) focuses on the distribution, features, properties and management of Red Brown Earths in the premium viticultural regions of the Barossa Valley and McLaren Vale, South Australia. The effects of irrigation method and water quality on the rate and extent of soil deterioration are emphasised. The review also discusses the irrigation of grapes (Vitis vinifera) and summarises previous research into the effect of sodicity and salinity on grape and wine characteristics. This chapter shows the importance of Red Brown Earths to Australian viticulture, but highlights their susceptibility to chemical and physical degradation. Degradation may be prevented or remediated by increasing organic matter levels, applying gypsum, modifying cropping and through tillage practices such as deep ripping. Chapter 2 provides general information on the two study sites investigated, one in the Barossa Valley and the other at McLaren Vale. Local climate, geology, geomorphology and soils are described. Chapter 3 details laboratory, field and sampling methods used to elucidate changes in soil chemical and physical properties following irrigation. The genesis of the non-irrigated Red Brown Earth in the Barossa Valley is described in Chapter 4, and is inferred from geochemical, soil chemical, layer silicate and carbonate mineralogical data. Elemental gain and loss calculations showed 42% of original parent material mass was lost during the formation of A and A2 horizons, while the Bt1 and Bt2 horizons gained 50% of original parent material mass. This is consistent with substrate weathering and illuviation of clay from surface to lower horizons. The depth distributions of all major elements were similar ; the A horizon contained lower amounts of major elements than the remainder of the profile, indicating this region was intensely weathered. This chapter also compares the non-irrigated site to the adjacent irrigated site (separated by 10 m) to determine if the sites are pedogenically identical and geochemical changes from irrigation. Many of the differences between the non-irrigated and irrigated sites appear to be correlated with variations in quartz, clay, Fe oxide and carbonate contents, with little geological variation between the sample sites. In Chapter 5 morphological, chemical and physical properties of a non-irrigated and irrigated Red Brown Earth in the Barossa Valley are compared. Alternating applications of saline irrigation water (in summer) and non-saline rain water (in winter) have caused an increase in electrical conductivity (EC [subscript se]), sodium adsorption ratio (SAR), bulk density (ρ b) and pH. This has resulted in enhanced clay dispersion and migration. Impacts on SAR and ρ b are more pronounced at points away from the dripper due to the presence of an argillic horizon, which has greatly influenced the variations in these soil properties with depth and distance from the dripper. Dispersion and migration of clay were promoted by alternating levels of EC, while SAR remained relatively constant, resulting in the formation of a less permeable layer in the Bt1 horizon. Clay dispersion (breakdown of micro-aggregate structure) was inferred from reduced numbers of pores and voids, alterations in colouring (an indication that iron has changed oxidation state) and increased bulk density (up to 30 %). Eleven years of irrigation changed the soil from a Calcic Palexeralf (non-irrigated) to an Aquic Natrixeralf (irrigated) (Soil Survey Staff, 1999). These results, combined with data from Chapter 4, were used to develop a mechanistic model of soil changes with irrigation. Chapters 6, 7 and 8 describe field experiments conducted in the Barossa Valley and McLaren Vale regions. This data shows seasonal and spatial variations in soil saturation extract properties ( EC [subscript se], SAR [subscript se], Na [subscipt se] and Ca [subscript se] ). At the Barossa Valley site (Chapter 6) non-irrigated soils had low EC [subscript se], SAR [subscript se], Na [subscript se] and Ca [subscript se] values throughout the sampling period. The irrigated treatments included eleven years of drip irrigation with saline water (2.5 dS / m) and also gypsum application at 0, 4 or 8 tonnes/hectare in 2001 and 2002. Salts in the profile increased with gypsum application rate, with high levels occurring midwinter 2002 prior to rainfall leaching salts. SAR has declined with gypsum application, particularly in the A horizon and at 100 cm from the dripper in the Bt1 horizon ; this has the potential to reflocculate clay particles and improve soil hydraulic conductivity. Chapter 7 presents further results from the Barossa Valley site, this treatment had been irrigated for 9 years with saline water (2.5 dS / m) prior to switching to a less saline water source (0.5 dS / m). The soil also received gypsum at 0, 4 or 8 tonnes / hectare in 2001 and 2002. It was found that the first few years are critical when switching to a less saline water source. EC declines rapidly, but SAR requires a number of years, depending on conditions, to decline, resulting in a period during which the Bt1 horizon may become dispersed. Gypsum application increased the EC [subscipt se] but not to the EC [subscript se] levels of soil irrigated with saline water. Chapter 8 examines soil chemical properties of a McLaren Vale vineyard, irrigated with moderately saline water (1.2 dS / m) since 1987 and treated with gypsum every second year since establishment. This practice prevented the SAR (< 8) rising and a large zone of the soil profile (20 to 100 cm from dripper) has a high calcium level (> 5 mmol / L). However, irrigation caused the leaching of calcium beneath the dripper in both the A and B horizons (0 to 20 cm from dripper) (< 4 mmol / L). Chapters 9 and 10 interpret and discuss results from continuous monitoring of redox potential (Eh) and soil solution composition in the Barossa Valley vineyard, irrigated with saline or non-saline water, and gypsum-treated at 0 and 4 tonnes / hectare. Soil pore water solution (Chapter 9) collected by suction cups is compared to results obtained in chapters 6 and 7. The soil has extended zones and times of high SAR and low EC. This was particularly evident in the upper B horizon, where the SAR of the soil remained stable throughout the year while the EC was more seasonally variable with EC declining during the winter months. The A horizon does not appear to be as susceptible to clay dispersion (compared to the B horizon) because during periods of low EC the SAR also declines, which may be due to the low CEC (low clay and organic matter content) of this horizon. Chapter 10 presents redox potentials (Eh) measured using platinum redox electrodes installed in the A, A2 and Bt1 horizons to examine whether Eh of the profile varies with irrigation water quality and gypsum application. Saline irrigation water caused the B horizon to become waterlogged in winter months, while less saline irrigation water caused a perched watertable to develop, due to a dispersed Bt1 horizon. Application of gypsum reduced the soil Eh particularly in the A2 horizon (+ 500 to + 50 mV) during winter. Thus redox potential can be influenced by irrigation water quality and gypsum applications. Chapter 11 incorporated site data from the Barossa Valley non-irrigated site into a predictive mathematical model, TRANSMIT, a 2D version of LEACHM. This model was used to predict zones of gypsum accumulation during long-term irrigation (67 years). When applied over the entire soil surface, gypsum accumulated at 60 to 90 cm from the dripper in the B horizon; higher application rates caused increased accumulation. When applied immediately beneath the irrigation dripper, gypsum accumulated in a 'column' under the dripper (at 0 to 35 cm radius from the dripper), with very little movement away from the dripper. Also, the zone of accumulation of salts from high and low salinity irrigation water was investigated. These regions were found to be similar, although concentrations were significantly lower with low salinity water. In low rainfall years salts accumulated throughout the B horizon (35 - 150 cm), while in periods of high rainfall (and leaching) the A, A2 and Bt1 horizons (0 - 60 cm) were leached, although at greater depths (80 - 150 cm) salt concentrations remained high. Chapter 12 summarises results and provides an understanding of soil processes in drip irrigated soils to underpin improved management options for viticulture. This study combines results from redox and soil solution monitoring, mineralogy, elemental gains and losses, and seasonal soil sampling to develop a mechanistic model of soil processes, which was combined with computer modelling to predict future properties of the soil. Major conclusions and recommendations of this study include : - Application of saline irrigation water to soil then ameliorated with gypsum - The first application of gypsum was leached by the subsequent irrigation from extended regions of the soil. As Na continues to enter the system via irrigation water, gypsum needs to be regularly applied. Otherwise calcium will be leached through the soil and SAR increases. - Application of non-saline irrigation water to soil then ameliorated with gypsum - The soil was found to only require one application at 8 tons / ha as this reduced SAR sufficiently. As less salt is entering the soil, subsequent gypsum applications can be at a lower rate or less frequently than required for saline irrigation water. - Gypsum applied directly beneath the dripper systems distributes calcium to a narrow region of the soil, while large regions of the soil require amelioration (high SAR) and are not receiving calcium. Therefore, gypsum application through the drip system or only beneath the dripper should be combined with broad acre application. - A range of methods to sample vineyards is recommended for duplex soils, including the use of saturation extracts, sampling time, sampling location (distance from dripper) and depth of sampling. This work is critical for vineyard management and may be applicable to other Australian viticulture regions with Red Brown Earths.Thesis (Ph.D.) -- University of Adelaide, School of Earth and Environmental Sciences, 2004.
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Lordan, Sanahuja Joan. "Irrigation and soil management strategies to improve fruit tree response in limiting soil conditions." Doctoral thesis, Universitat de Lleida, 2015. http://hdl.handle.net/10803/289501.
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La transformació de terres marginals, juntament amb un augment dels processos de degradació del sòl (p. e. salinització) estan traslladant l'agricultura a sòls més desfavorables, fet que obliga al desenvolupament de noves estratègies de maneig dels cultius. Durant els últims anys s'han introduït noves estratègies de reg, com el reg localitzat enterrat (subsurface drip irrigation, SDI) o el reg deficitari controlat, tot i que resulta necessari avaluar la seva viabilitat i sostenibilitat quan són aplicades en sòls amb propietats físiques limitants. Alhora, l'ús d'esmenes orgàniques i les tècniques d’aeració forçada estan sorgint com a mètodes de recuperació de sòls a baix cost, que podrien millorar potencialment el rendiment dels cultius en situacions desfavorables. És important estudiar els efectes d'aquestes estratègies i tècniques sobre les propietats del sòl, així com en la fisiologia dels cultius i la seva productivitat, tot i que també sobre paràmetres de qualitat d'importància creixent en el sector fructícola, com el potencial de conservació de la fruita. L'objectiu general d'aquesta tesi ha estat el d'avaluar diferents estratègies de maneig del sòl i de reg, i estudiar els seus efectes en plantacions de presseguer i nectarina en sòls amb condicions físiques limitants.La transformación de tierras marginales, junto con un aumento de los procesos de degradación del suelo (p. ej. salinización) están trasladando la agricultura a suelos más desfavorables, lo que obliga al desarrollo de nuevas estrategias de manejo de los cultivos. Durante los últimos años se han introducido nuevas estrategias de riego, como el riego localizado enterrado (subsurface drip irrigation, SDI) o el riego deficitario controlado, a pesar de que resulta necesario evaluar su viabilidad y sostenibilidad cuando son aplicadas en suelos con propiedades físicas limitantes. Al mismo tiempo, el uso de enmiendas orgánicas y las técnicas de aireación forzada están surgiendo como métodos de recuperación de suelos a bajo coste, que podrían mejorar potencialmente el rendimiento de los cultivos en situaciones desfavorables. Es de suma importancia el estudiar los efectos de estas estrategias y técnicas sobre las propiedades del suelo, así como en la fisiología de los cultivos y su productividad, aunque también sobre parámetros de calidad de importancia creciente en el sector frutícola, como el potencial de conservación de la fruta. El objetivo general de esta tesis fue el de evaluar diferentes estrategias de manejo de suelo y riego, y estudiar sus efectos en plantaciones de melocotón y nectarina en suelos con condiciones físicas limitantes.
Transformation of marginal land along with an increase of soil degradation processes (e.g. salinization) is moving the agriculture into more unfavorable soils, forcing the development of new management strategies. Subsurface drip irrigation (SDI) and deficit irrigation strategies have been widely studied although it is necessary to evaluate their feasibility and sustainability when applied in soils with limiting physical properties. At the same time, organic soil amendments and oxygation techniques are arising as low-cost soil reclamation methods that could potentially improve the crop performance under such situations. It is of paramount importance to study the effects of these strategies and techniques on soil properties as well as on crop physiology and productivity, but also on some quality parameters of growing importance in the fruit sector, such as fruit storability. The general aim of this thesis was to assess various soil management and irrigation strategies and study their effects on peach and nectarine orchards under limiting soil conditions.
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Peräläinen, Lina. "Variations in the performance of maize (Zea mayz) yield under reclaimed wastewater irrigation in south-eastern Australia : management of salinity, water and nutrient budgets /." Umeå : Sveriges lantbruksuniversitet, 2006. http://epsilon.slu.se/10320999.pdf.
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Miranda, Casey R. "Effects of Recycled Water On Landscape Plants." DigitalCommons@CalPoly, 2010. https://digitalcommons.calpoly.edu/theses/354.
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ABSTRACT EFFECTS OF RECYCLED WATER ON LANDSCAPE PLANTS Casey Ray Miranda Recycled water is water that has been previously used, has suffered a loss of quality, and has been properly treated for redistribution (Wu et al. 2001). The use of recycled water as an alternative to fresh water in the landscape can have positive and negative effects. Experimentation on 40 different plant species during a 32 week period (2 phases of 16 weeks), was conducted to analyze the effects of recycled water irrigation on the appearance of landscape plants. Each species of plant was planted into 10 individual number 2 pots and irrigated with recycled water daily. Media and water were tested for nutrients and other constituents. In phase I there were four different species of grasses and grass-like plants, five different perennials, five species of shrubs, and four annuals tested; while phase II tested four species of herbaceous perennials, eight different species of shrubs, six species of groundcovers, and four species of annuals. All tests were conducted at the Paso Robles Waste Water Treatment Plant. Of the grasses and grass like species Yucca spp. and Buchloe spp. performed best. Osteospermum fruticosum, Lavandula angustifolia, Rosmarinus officinalis, Phormium tenax, and Pennisetum setaceum had the best appearance of the herbaceous perennials tested. For the shrubs, Coprosma repens, Cistus purpureus, Dodonea viscosa, Eleagnus pungens, Baccharis pilularis, Ceanothus thysiflorus, Thuja orientalis, and Nerium oleander had the best appearance when irrigated with recycled water. The best annuals were Senecio cineraria, Antirrhinum majus, Primula spp., Viola spp., and Calendula officinalis. Of the groundcovers Heuchera spp., Lonicera japonica, Vinca major, Hedera helix, and Ceanothus griseus had the best results. From the experiment a list of tolerant and non-tolerant plants was compiled (Appendices 1 and 2). While many plants were capable of developing and growing normally, other plants were sensitive to recycled water irrigation. In order to prevent salt damage to plants and expand the use of recycled water, salt tolerance of landscape plant material must be identified (Niu et.al, 2006).
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Soares, Tales Miler. "Utilização de águas salobras no cultivo da alface em sistema hidropônico NFT com alternativa agrícola condizente ao semi-árido brasileiro." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/11/11143/tde-29112007-093534/.
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Muitas vezes, a agricultura extensiva falha sob as condições semi-áridas da região Nordeste do Brasil, onde há escassez de águas superficiais e as chuvas são irregulares. O uso de águas subterrâneas poderia melhorar a produtividade das culturas. Mas, devido à condição geológica, é freqüente a ocorrência de águas subterrâneas salobras. A utilização dessas águas levaria à salinização do solo. Além disso, os poços perfurados têm baixas vazões. Nesse cenário, a hidroponia pode ser condizente à produção intensiva, baseada em pequenas áreas. A eficiência do uso da água na hidroponia é reconhecidamente maior que no solo porque torna mínima a perda por evaporação. Além disso, a hidroponia poderia aumentar a tolerância das culturas à salinidade. Isso permitiria o uso de águas salobras e, como benefício extra, incrementaria a proteção ambiental. Em hidroponia, não há o potencial mátrico que leva à diminuição da energia livre da água. Também, a própria estrutura funciona como sistema de drenagem. Os sais acumulados ao final do processo produtivo podem ser facilmente dirigidos para fora do sistema. Com essa hipótese, foram conduzidos experimentos para avaliar a tolerância da alface (cultivar Verônica) à salinidade em hidroponia e em solo. Foi construída uma estrutura experimental (40 parcelas independentes) para simular o cultivo na técnica do fluxo laminar de nutrientes (NFT). Para o cultivo em solo, foram utilizados vasos de 12 L e mulch plástico. Foi observado que na hidroponia NFT é possível empregar águas mais salobras que no cultivo em solo. Quando se têm disponíveis água doce e salobra, pode ser mais interessante usar água doce no preparo da solução nutritiva e água salobra na reposição ao volume consumido. O uso de água salobra para o preparo da solução nutritiva e da água doce para a reposição ao consumo produziu maiores perdas relativas sobre o rendimento do que a salinização gradual. Esse resultado foi proporcionado pela precocidade da alface. Em relação à tolerância, a salinidade limiar da alface 'Verônica' cultivada em hidroponia NFT foi estimada em 4,03 dS m-1. Sob as mesmas condições experimentais, a tolerância em solo foi estimada em 2,51 dS m-1. Esses resultados confirmam a hipótese levantada e permitem apresentar uma alternativa agrícola condizente à realidade de muitas famílias isoladas no semi-árido brasileiro.Several times, the extensive agriculture fails under semi-arid conditions in the Northeast region of Brazil, where the surface water is shortage and the pluvial precipitation is irregular. The use of groundwaters could increase the crops yield. However, due to the geological factors, it is usual the occurrence of brackish groundwaters in this region. The utilization of these waters would carry to soil salinization. Moreover, the opened deep tubewells often have low capacity. In this scenario, the hydroponics systems may be suitable to intensive production based in reduced areas. The higher water use efficiency in soilless cultivation is a well reported advantage, because in this system the water loss by evaporation is minimum. In hydroponics systems could be increase the crop salt tolerance. This would permit the brackish water use and, as an extra benefit, would increase the environmental safety. In hydroponics system, there is no the matric potential, which decreases the free-energy of water. Furthermore, the hydroponics structure operates as a drainage system. The accumulated salts, at the end of the period, may be easily removed from system. In order to test this hypothesis, were carried out experiments to evaluate the lettuce (cv. Verônica) salt tolerance under soil and hydroponics conditions. It was constructed a structure (40 independent experimental units) to simulate the Nutrient Technique Film (NFT) cultivation. For the soil experiment, it was used 12 L recipients and plastic mulch. It was registered that is feasible use waters more brackish in NFT system than in soil. For available of brackish and nonsaline waters, it was more productive to use non-saline water to prepare the nutrient solution and brackish water to supply the water consumption. Higher yield losses were observed with the use the brackish water to prepare nutrient solution and the non-saline water to replace the water consumption. The nutrient solution salinization was less depreciative to yield than the constant salinity. This finding was providing by the lettuce precocity. In relation to the salt tolerance in NFT system, the lettuce salinity threshold was estimated in 4.03 dS m-1. Under the same experimental conditions, the tolerance in soil was estimated in 2.51 dS m-1. These results confirmed the hypothesis and permit to present an agricultural alternative suitable to reality of many isolated families in Brazilian semi-arid.
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Cunha, Cleyton Saialy Medeiros. "Relação entre solos afetados por sais e concentração de metais pesados em quatro perímetros irrigados no Ceará." reponame:Repositório Institucional da UFC, 2013. http://www.repositorio.ufc.br/handle/riufc/16893.
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CUNHA, Cleyton Saialy Medeiros. Relação entre solos afetados por sais e concentração de metais pesados em quatro perímetros irrigados no Ceará. 2013. 94 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Centro de Ciências Agrárias, Departamento de Ciências do Solo, Programa de Pós-Graduação em Agronomia - Solos e Nutrição de Plantas, Fortaleza-CE, 2013Submitted by Nádja Goes (nmoraissoares@gmail.com) on 2016-05-19T13:15:40Z No. of bitstreams: 1 2013_dis_csmcunha.pdf: 1688602 bytes, checksum: 5f3d29629a4cee68fa5f40aab127fdf6 (MD5)
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Researches with salinization in irrigated areas, for the presence of heavy metals are still incipient. These metals have been consistently found in areas irrigated groups and are associated with environmental impact, being pollutants because of their toxicity and persistence in the environment. The study aimed to determine the concentration of heavy metals and to establish correlations between them in salt affected soils less than four (4) in irrigated Ceará (Baixo-Acaraú; Morada Nova; Curu-Pentecost and Ico-Lima Campos). Samples were collected at depth of 0-10 and 10-20 cm in 10 points within each perimeter, being (1) point within each perimeter, referring to soils preserved vegetation, totaling (80) samples. Were obtained the total contents of metals, as well as multivariate analyzes were performed (canonical correlation analysis and factorial) between attributes related to salinization (pH, CE, CTC and PST) and variable consisting of the heavy metals (Al, B, Mn , Mo, Si, Zr, Cr, Fe, V, Ni, Pb, Ti, Zn, As, Cd, Co and Cu) in the 0-20 cm. It was concluded that: a) The levels of heavy metals and elements in soils of the four perimeters followed the following order: Fe, Al, Si, Ti, Mn, Zn, Cr, V, Ni, Cu, Co, B, Pb , Se, Cd, Mo, Zr, and this order, in general, independent of the surface and subsurface layers considered. b) The reference values for heavy metals and quality data obtained in this study, in general, were low compared to the values stipulated by environmental agencies at Brasil (CONAMA and CETESB). In fact, for all the soil samples, the levels of As and Hg were below the limit of detection apparatus (0.01). c) Soil attributes related to salinity CTC, pH, EC and PST contributed to explain the levels of heavy metals in soils of the four irrigation schemes, when analyzed together, however, were not able to explain when analyzed individually. Following the order of importance: CTCT > pH > PST > EC. d) Correlations were observed between metallic elements analyzed in this study (B, Mo, Si, Zr, Cr, Ni, Pb, Ti, Zn, Cd, Co, Se and Cu) with Fe, Mn, Al, Ti and V, or even, geochemical affinities between the elements in the four soils irrigated Ceará.
As pesquisas com salinização nos perímetros irrigados, quanto à presença de metais pesados ainda são incipientes. Estes metais vêm sendo encontrados em áreas irrigadas e estão associados a grupos de impactos ambientais, por serem poluentes devido à sua toxicidade e persistência no ambiente. O trabalho teve como objetivo verificar a concentração de metais pesados e verificar as correlações existentes entre eles em solos afetados por sais referentes a quatro (4) perímetros irrigados no Ceará (Baixo-acaraú; Morada Nova; Curu-Pentecoste e Icó-Lima Campos). Foram coletadas amostras de solo nas profundidades de 0–10 e 10-20 cm em 10 pontos dentro de cada perímetro, sendo (1) ponto, dentro de cada perímetro, referente a solos de vegetação preservada, totalizando oitenta (80) amostras. Foram obtidos os teores pseudototais de metais, assim como foram realizadas análises multivariadas (análise de correlação canônica e fatorial), entre atributos relacionados com a salinização (CTC, PST, pH e CE) e variáveis constituídas pelos metais pesados (Al, B, Mn, Mo, Si, Zr, Cr, Fe, V, Ni, Pb, Ti, Zn, As, Cd, Co e Cu) na camada de 0-10 e 10-20. Concluiu-se que: a) Os teores de metais pesados e elementos nos solos dos quatro perímetros seguiram a seguinte ordem decrescente: Fe, Al, Si, Ti, Mn, Zn, Cr, V, Ni, Cu, Co, B, Pb, Se, Cd, Mo, Zr, sendo esta ordem, no geral, independente das camadas superficiais e subsuperficiais consideradas. b) Os valores de referência de qualidade para metais pesados e elementos obtidos neste estudo, de modo geral, foram considerados baixos, quando comparados com os valores estipulados por órgãos ambientais (CONAMA e CETESB). Inclusive, para todas as amostras de solo, os teores de As e Hg, ficaram abaixo de limite de detecção do aparelho (0,01). c) Os atributos do solo relacionadas com a salinização CTC, pH, PST e CE contribuíram para explicar os teores de metais pesados nos solos dos quatro perímetros irrigados, quando analisados em conjunto; todavia, não foram capazes de explicar quando analisados de forma individual; seguindo a ordem de importância: CTC > pH > PST > CE. d) Foram verificadas correlações entre os elementos metálicos analisados neste estudo (B, Mo, Si, Zr, Cr, Ni, Pb, Ti, Zn, Cd, Co, Se e Cu) com o Fe, Mn, Al, Ti e V, ou, ainda, afinidades geoquímicas entre os elementos, nos solos dos quatro perímetros irrigados do Ceará.
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Bessa, Michele Campos. "Estabelecimento de plantas nativas da caatinga em um gradiente de salinidade do solo, sob condiÃÃes controladas." Universidade Federal do CearÃ, 2012. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=10134.
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Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgicoFundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico
A salinidade à um dos estresses abiÃticos que mais limita a produÃÃo vegetal em razÃo de seus efeitos negativos no crescimento e desenvolvimento das plantas. Em Ãreas degradas por sais verifica-se que o estabelecimento de espÃcies arbÃreas nÃo à fÃcil, principalmente em cultivos de sequeiro e em regiÃes com precipitaÃÃes muito baixas. O objetivo do presente trabalho consiste em avaliar o estabelecimento de doze espÃcies de plantas lenhosas nativas da Caatinga em um gradiente de salinidade do solo, em ambiente protegido, com vistas à obtenÃÃo de subsÃdios para estabelecimento de espÃcies promissoras em condiÃÃes de campo. O trabalho foi dividido em duas etapas: 1. Crescimento e grau de tolerÃncia à salinidade de doze espÃcies nativas da Caatinga em ambiente protegido - O delineamento utilizado foi de blocos ao acaso, no esquema de parcelas subdivididas tendo na parcela mudas de doze espÃcies nativas da Caatinga (Aroeira, Ipà roxo, MororÃ, Mulungu, SabiÃ, Pau-mocÃ, Angico, Catanduva, Frei Jorge, Jurema branca, Tamboril, e Jurema preta) e na subparcela, os cinco nÃveis de salinidade do solo (1,2; 2,7; 4,7; 6,7; 8,4 dS m-1), com cinco repetiÃÃes. Para os nÃveis moderados de salinidade do solo verificou-se que todas as espÃcies se comportaram como tolerantes ou moderadamente tolerantes à salinidade. Considerando-se os graus de reduÃÃo na produÃÃo de matÃria seca total, no maior nÃvel de salinidade, observou-se que apenas a aroeira mostrou-se tolerante à salinidade (T); o ipà roxo e mulungu responderam como moderadamente tolerantes (MT); o mororà e o pau mocà moderadamente sensÃveis (MS); a maioria das espÃcies, sabiÃ, angico, catanduva, frei jorge, jurema branca, jurema preta e tamboril, foram classificadas como sensÃveis (S), com reduÃÃes superiores a 60%; 2. Trocas gasosas e teores de solutos orgÃnicos e inorgÃnicos em seis espÃcies nativas da Caatinga sob condiÃÃes de salinidade - O delineamento utilizado foi de blocos ao acaso, no esquema de parcelas subdivididas tendo na parcela seis mudas de espÃcies nativas da Caatinga (Aroeira, Ipà roxo, MororÃ, Mulungu, Sabià e Pau-mocÃ,), as quais apresentaram diferentes graus de tolerÃncia à salinidade (etapa 1), e na subparcela os cinco nÃveis de salinidade do solo (1,2; 2,7; 4,7; 6,7; 8,4 dS m-1), com cinco repetiÃÃes. A salinidade provocou reduÃÃo nas trocas gasosas foliares, sendo esse efeito independente da espÃcie estudada. No entanto, se observa um maior controle estomÃtico e maior eficiÃncia intrÃnseca no uso da Ãgua nas espÃcies que apresentaram maiores graus de tolerÃncia à salinidade, ou seja, aroeira, ipà roxo e mulungu. No presente estudo nÃo foi possÃvel estabelecer um relacionamento claro entre o acÃmulo dos solutos orgÃnicos estudados e a tolerÃncia à salinidade das seis espÃcies nativas da Caatinga. PorÃm, observou-se forte relaÃÃo entre a relaÃÃo Na/K e os teores de Na nas folhas e o grau de tolerÃncia das espÃcies estudadas, com as espÃcies mais tolerantes apresentando menores variaÃÃes e menores valores com o aumento da salinidade do solo.
Salinity is one of the abiotic stresses that most limits crop production because of its negative effects on plant growth and development. In areas degraded by salts it appears that the establishment of tree species is not easy, especially in rainfed crops and regions with very low precipitation. The objective of this study is to evaluate the establishment of twelve species of woody plants native to the Caatinga in a gradient of soil salinity in greenhouse, in order to obtain grants for the establishment of promising species under field conditions. The work was divided into two steps: 1. Growth and degree of salinity tolerance of twelve native species of Caatinga in a protected environment - The experimental design was randomized blocks in split plots with seedlings in the plot of twelve native species of the Caatinga (Aroeira, Ipà roxo, MororÃ, Mulungu, SabiÃ, Pau-mocÃ, Angico, Catanduva, Frei Jorge, Jurema branca, Tamboril, e Jurema preta) and subplots, the five levels of soil salinity (1.2, 2.7, 4.7, 6.7, 8,4 dS m-1), with five replicates. For moderate levels of soil salinity was found that all species are as tolerant or moderately tolerant to salinity. Considering the degree of reduction in total dry matter production, the highest level of salinity, it was observed that only the mastic proved to be tolerant to salinity (T); The Ipà and mulungu behaved as moderately tolerant (MT); the mororà and pau-mocà moderately susceptible (MS); most species, sabiÃ, angico, catanduva, frei jorge, jurema branca, jurema preta and tamboril, were classified as sensitive (S), with reductions of more than 60%. 2. Gas exchange and concentration of organic and inorganic solutes in six species native to the Caatinga under saline conditions - The design was randomized blocks in split plots with the plot six native species of Caatinga (Aroeira, Ipà roxo, MororÃ, Mulungu, Sabià e Pau-mocÃ,), which showed different degrees of salinity tolerance (step 1), and subplot five levels of soil salinity (1.2, 2.7, 4.7, 6.7, 8.4 dS m-1), with five replicates. Salinity caused reduction in leaf gas exchange, and this effect is independent of the species studied. However, observe a greater stomatal control and greater intrinsic efficiency of water use in species with higher degrees of salt tolerance, ie, aroeira, ipà roxo and mulungu. In the present study could not establish a clear relationship between the accumulation of organic solutes studied and salt tolerance of six species native to the Caatinga. However, observed a strong correlation between the Na/K and Na in the leaves and the degree of tolerance of species with species more tolerant of minor variations and presenting lower values with increasing soil salinity.
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Nascimento, Jéssica Garcia. "Malhas coloridas de sombreamento e soluções nutritivas de fertirrigação na cultura da gérbera (Gerbera jamesonii) em ambiente protegido." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/11/11152/tde-21062018-175123/.
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A floricultura é uma atividade altamente rentável e exerce um papel importante no agronegócio brasileiro, se destacando cada vez mais em relação ao seu faturamento anual. Dentre as flores mais cultivadas e comercializadas, as gérberas (Gerbera jamesonii) são conhecidas pela grande quantidade de cores de suas inflorescências. O objetivo do presente trabalho foi avaliar o desenvolvimento e a produtividade da cultura da gérbera em ambiente protegido associado a malhas vermelha, azul e preta de sombreamentos e fertirrigadas com cinco soluções nutritivas de fertirrigação, elaboradas a partir da diluição (25%, 50%, 75%) e concentração (125%) da solução proposta por Hoagland e Arnon (1950) (solução padrão, 100%), sobre as características que conferem a qualidade da planta para comercialização em vasos. A malha azul associada à fertirrigação com concentração de 25% dos nutrientes da solução padrão proporcionaram maior massa fresca e seca de capítulos florais, hastes e total das gérberas e, ainda, maior massa seca das folhas. Os tratamentos aplicados não ifluenciaram o número de capítulos e de folhas e a classificação segundo os padrões qualidade. O diâmetro do capítulo floral não foi afetado pelos tratamentos de fertirrigação e sombreamento; entretanto, o diâmetro e a altura das hastes das gérberas foram reduzidos com a apliacação da solução mais concentrada (125%). Oíndice de estresse hídrico (CWSI) da cultura foi mais próximo de 1, nas três malhas coloridas, nos horários próximos ao meio do dia e aos 58 DAT foi verificado maior estresse das plantas sombreadas pelas malhas vermelhas. O índice de clorofila total (índice Falker) aos 59 e 99 DAT foi menor na malha vermelha, o que pode indicar maior eficiência das plantas sob esta malha, uma vez que não houve redução da produtividade das gérberas neste ambiente. Os teores de antocianina foram muito semelhantes nas folhas das gérberas cultivadas sob as malhas coloridas, sendo observada uma maior média do pigmento nas gérberas cultivadas sob a malha azul.The flower culture is a highly profitable activity and plays a major role in agribusiness, increasingly standing out in terms of annual sales. One of the most cultivated and marketed flowers, gerbera (Gerbera jamesonii), is known for its abundance of colors of its inflorescences. This work aimed to evaluate development and productivity of gerbera culture in protected environment associated to shading meshes of red, blue and black under fertirrigation with five nutritional solutions elaborated from the dilution ( 25%, 50%, 75%) and concentration (125%) of the solution proposed by Hoagland and Arnon (1950) (standard solution, 100%) on the characteristics that confer quality to the plant for marketing in pots. The blue mesh associated with fertigation of 25% of nutrient concentration of the standard solution provided fresh and dry mass of inflorescence, stems and total of gerbera, as well as greater dry mass of leaves. The treatments applied did not influence the number of inflorescences and leaves, as well as the classification of quality standards. The diameter of inflorescences was not affected by fertigation and shading; however, stem diameter of gerbera was reduced with the application of concentrated solution (125%). The crop water stress index (CWSI) was closer to 1, in the three colored meshes, at times near the middle of the day, and at 58 DAT, greater stress was verified in plants shaded by red meshes. The index of total chlorophyll (Falker index) at 59 and 99 DAT was smaller in red fabric, which may indicate greater efficiency of plants under this mesh, since there was no reduction in the productivity of gerbera in this environment. The contents of anthocyanin were very similar in leaves of gerbera grown under colored meshes, being observed a grater average of the pigment in gerbera grown under the blue fabric.
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Blanco, Flávio Favaro. "Tolerância do pepino enxertado à salinidade em ambiente protegido e controle da salinização do solo." Universidade de São Paulo, 2000. http://www.teses.usp.br/teses/disponiveis/11/11143/tde-10022003-141143/.
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A aplicação de fertilizantes via água de irrigação é prática comum para cultivos em ambiente protegido, o que pode resultar na salinização do solo se o manejo da irrigação não for adequado. Com isso, é de grande importância que se estabeleça a tolerância das culturas à salinidade e o controle eficiente da irrigação para cada cultura a fim de se promover a lixiviação do excesso de sais da zona radicular até um nível tolerado pelas plantas. O presente trabalho teve o objetivo de estabelecer um manejo adequado da fertilização e da irrigação para a cultura do pepino enxertado em ambiente protegido, visando o controle da salinidade do solo, e avaliar métodos de recuperação do solo salinizado. Para isso, foi conduzido um experimento em uma estufa de 110 m 2 para estudar o efeito de diferentes salinidades da água de irrigação (S1=1,58 dS.m -1, S2=3,08 dS.m -1 e S3=5,13 dS.m -1 ), diferentes lâminas de água (L0=1,00.ETc e L1=1,25.ETc) e duas frequências de aplicação da lâmina L1 (F1=em todas as irrigações e F2=quando a lâmina de irrigação acumulada em L0 for igual a 100 mm) no desenvolvimento vegetativo e produção do pepino, cv. Hokushin, enxertado em Cucurbita spp., híbrido Excite-Ikki. O manejo da irrigação foi realizado através de tensiômetros instalados a 15 e 30 cm de profundidade e da evaporação de um tanque reduzido, instalado no interior da estufa. Os resultados obtidos demonstraram que o aumento de uma unidade de salinidade da água de irrigação reduziu a produção total e comercial em 2,83 e 2,99%, respectivamente, não apresentando diferenças significativas. O número de frutos comerciais por planta foi reduzido em 3,32% para cada incremento de uma unidade de salinidade. A salinidade também afetou significativamente a área foliar unitária e o índice de área foliar, bem como a altura e o diâmetro do colo da planta. As diferentes lâminas de irrigação e frequências de aplicação de L1 não resultaram em diferenças significativas para a produção e componentes de produção da cultura. O aumento de uma unidade de salinidade do solo reduziu a produção e o número de frutos por planta, comercial e total, em 7,24 e 6,71% e 8,04 e 7,58%, respectivamente, os quais foram bem inferiores aos valores citados na literatura. A pequena redução na produção e a ausência de diferenças significativas entre os níveis de salinidade não permitiram definir a tolerância do pepino à salinidade e o manejo da lâmina de irrigação quando a água utilizada apresenta alto teor salino. A salinidade do solo aumentou proporcionalmente com o aumento da salinidade da água, sendo que as lâminas de irrigação e as frequências de aplicação de L1 não foram suficientes para reduzir a salinidade do solo, embora a frequência F2 tenha resultado em um aumento mais lento da salinidade. A lixiviação do excesso de sais do solo após o cultivo demonstrou que a aplicação da lâmina de lavagem por gotejamento foi mais eficiente do que a inundação na redução da salinidade do solo. Concluiu-se que a lâmina relativa de lavagem e o valor do coeficiente k a serem utilizados são, respectivamente, de 0,9 e 0,1 para gotejamento e 1,3 e 0,2 para inundação, com base na lâmina calculada pela equação de Rhoades & Loveday (1990).Fertilizers application through irrigation water is a very common practice for greenhouse cultivation conditions, which can result in the soil salinization if irrigation management is not appropriated. It is very important to establish the crop tolerance to salinity and the efficient irrigation control for each crop to promote leaching of excess salts from the root zone until a tolerated level by plants. The present work had the aim to establish an adapted management of fertilization and irrigation for grafted cucumber cultivated in greenhouse, in order to control the soil salinity, and to evaluate methods of salinized soil reclamation. An experiment has been carried out in a 110 m 2 greenhouse to study the effects of different irrigation water salinity (S1=1,58 dS.m -1 , S2=3,08 dS.m -1 and S3=5,13 dS.m -1 ), different irrigation water depth (L0=1,00.ETc and L1=1,25.ETc) and two applications frequencies of L1 (F1=at every irrigations and F2=when accumulated irrigation water depth in L0 reaches 100 mm) on vegetative development and yield of cucumber, cv. Hokushin, grafted onto Cucurbita spp., hybrid Excite-Ikki. Irrigation management was made by tensiometers installed at 15 and 30 cm deep and by a reduced pan evaporation, installed inside the greenhouse. The results showed that the increment of one unit of irrigation water salinity reduced the total and marketable yield at 2,83 and 2,99%, respectively, not showing significantly reduction. Marketable fruits number per plant was reduced at 3,32% for each increment of one unit of salinity. Salinity also affected significantly the unitary leaf area and the leaf area index, as the height and stem diameter of the plants. The different irrigation water depths and frequencies of L1 application did not result in differences for yield and yield components. Each increment of one unit of salinity reduced yield and fruit number per plant, marketable and total, of 7,24 and 6,71% and 8,04 and 7,58%, respectively, which were smaller than that found on literature. Little reduction in yield and the lack of significantly differences between the levels of salinity did not allow to define cucumber tolerance to salinity and the irrigation management for high salinity irrigation water. Soil salinity increased proportionally to irrigation water salinity increasing, but irrigation water depths and application frequencies of L1 were not sufficient to reduce soil salinity, though the frequency F2 resulted in a slower increasing of soil salinity. Leaching of excess salts after cultivation showed that the application of leaching water depth by drip irrigation was more effective than the application by flooding on soil salinity reduction. We concluded that the relative leaching depth and the k coefficient value to be adopted are, respectively, 0,9 and 0,1 for drip irrigation and 1,3 and 0,2 for flooding, based on water depth calculated by equation of Rhoades & Loveday (1990).
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Cosme, Christiano Rebouças. "Avaliação da qualidade da água proveniente de estações de tratamento de água salobra na zona rural do município de Mossoró, RN." Universidade Federal Rural do Semi-Árido, 2011. http://bdtd.ufersa.edu.br:80/tede/handle/tede/483.
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Previous issue date: 2011-03-30Conselho Nacional de Desenvolvimento Científico e Tecnológico
In Brazil, mainly in the semiarid region, a major challenge is to promote the water supply to households in rural areas. Groundwater is identified as a viable alternative to ensure the access of rural communities in the northeast to water from public investment in drilling wells. However, these water sources in most cases have use restrictions for human consumption, because they present problems of salinity. The technology of reverse osmosis has been widely used for treatment of brackish water, with successful experiences in most locations where units have been deployed in water treatment by desalination. Many rural communities in Mossoró, RN, are supplied with water from the aquifer Jandaíra, high salt concentration, which is treated in desalination plants, allowing its use for human consumption. In these communities, the reject brine of the process of desalination is not receiving any treatment or proper disposal, being dumped straight into the ground and, when used in irrigation of crops there are no scientific-technical reasons for their use, causing problems of soil salinization. Due to the impacts caused by the use of brackish or reject brine for irrigation in the soil, to enable their use should always adopt some special practices of water management and soil for salinity control. As the majority of crops grown in the region classified as sensitive to moderately sensitive to salinity, there is the need to better characterize these waters, to establish the appropriate management of plants, soil and irrigation systems. As the majority of crops grown in the region are classified as sensitive to moderately sensitive to salinity, there is the need to better characterize these waters, to establish the appropriate management of plants, soil and irrigation systems. Thus, this study aimed to evaluate the quality of water for irrigation in rural communities of Mossoró, supplied with brackish water from tube wells equipped with desalination, providing this information as a tool to aid the proper management and use of these waters irrigation. 30 rural communities were selected to perform the collection of samples of water from the waste generated in the desalination, purified and in its natural form (brackish water of the well). In the collected samples were determined at electric conductivity (ECw), pH and concentrations of Na+, Ca2+, K+, Cl-, HCO3 - e CO3 2-, in addition, the sodium adsorption ratio (SAR). The Analyses of water samples were interpreted as to risk of salinity, sodicity, toxicity of ions and other quality parameters. The results show that water of the wells rural communities studied, have restrictions to their use in agriculture, as to risks of salinity and sodicity of the soil, especially the waters of the communities: São Romão, Boa Fé and Pau Branco. the reject brine of the desalination have high concentrations of salts, especially in communities of Boa Fé and Puxa Boi, compromising their use for irrigation, and, the desalinated water, although they have low concentrations of salts have restrictions on the problems of infiltration into the soil, if by chance, are employed in irrigation.
No Brasil, principalmente na região semiárida, um grande desafio é promover o abastecimento de água às famílias residentes nas áreas rurais. As águas subterrâneas são apontadas como uma alternativa viável para garantir o acesso das comunidades rurais do nordeste à água, a partir de investimentos públicos na perfuração de poços tubulares. Entretanto, essas fontes hídricas apresentam na maioria dos casos restrições de uso para dessedentamento humano, por apresentarem problemas de salinidade.A tecnologia da osmose reversa tem sido amplamente utilizada para o tratamento da água salobra, com experiências de êxito na maioria das localidades aonde têm sido implantadas as unidades de tratamento de água por dessalinização. Muitas comunidades rurais de Mossoró, RN, são abastecidas com água proveniente do aquífero Jandaíra, de elevada concentração de sais, a qual é tratada em dessalinizadores, possibilitando sua utilização para consumo humano. Nessas comunidades, o rejeito do processo da dessalinização não está recebendo qualquer tratamento ou destinação adequada, sendo despejado diretamente no solo e, quando utilizados na irrigação de culturas não há qualquer fundamentação técnico-científica para o seu uso, causando problemas de salinização nos solos. Devido aos impactos causados pelo uso de águas salobras ou de rejeito salino na irrigação no solo, para viabilizar a sua utilização deve-se sempre adotar algumas práticas especiais de manejo da água e do solo para o controle da salinidade. Sendo a maioria das culturas exploradas na região classificadas como sensíveis a moderadamente sensíveis à salinidade, surge a necessidade de melhor caracterizar essas águas, para se estabelecer o manejo adequado das plantas, solo e sistemas de irrigação. Assim, o presente trabalho objetivou avaliar a qualidade da água para fins de irrigação de comunidades rurais de Mossoró, abastecidas com águas salobras provenientes de poços tubulares, dotados de dessalinizadores, fornecendo estas informações como uma ferramenta de auxílio para o manejo adequado da utilização destas águas na irrigação. Foram selecionadas 30 comunidades rurais para realização das coletas de amostras das águas do rejeito gerado na dessalinização, purificadas e na sua forma natural (água salobra de poço). Nas amostras coletadas foram determinadas a condutividade elétrica da água (CEa), o pH e concentrações de Na+, Ca2+, K+, Cl-, HCO3 - e CO3 2-; além disso, a razão de adsorção de sódio (RAS). As análises das amostras de água foram interpretadas quanto aos riscos de salinidade, sodicidade, toxidade de íons e outros parâmetros de qualidade. Os resultados mostram que as águas dos poços das comunidades rurais estudadas possuem restrições para a sua utilização na agricultura, quanto aos riscos de salinização e sodificação do solo, principalmente as águas das comunidades: São Romão; Boa Fé e Pau Branco; as águas de rejeito da dessalinização possuem elevadas concentrações de sais, principalmente nas comunidades de Boa Fé e Puxa Boi, comprometendo a sua utilização para a irrigação e as águas dessalinizadas, embora possuírem baixos teores de sais têm restrições quanto a problemas de infiltração no solo, caso venham a ser empregadas para irrigação.
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Neves, AntÃnia Leila Rocha. "EstratÃgias visando o uso sustentÃvel de Ãgua salina em um ciclo de rotaÃÃo cultural feijÃo-de-corda/girassol." Universidade Federal do CearÃ, 2012. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=8710.
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O crescimento da populaÃÃo mundial e a crescente demanda de Ãgua para atender o consumo das famÃlias e os demais setores da economia, tÃm despertado para o aproveitamento de fontes alternativas ou Ãguas de qualidade inferior, tais como as Ãguas salinas e residuÃrias. O objetivo desse trabalho foi realizar uma avaliaÃÃo preliminar sobre a situaÃÃo dos dessalinizadores instalados pelo Governo do Estado do Cearà na regiÃo de Pentecoste, CearÃ, e, em seguida, avaliar estratÃgias de manejo da irrigaÃÃo (uso cÃclico de Ãgua salina, mistura de fontes de Ãgua de diferentes salinidades e utilizaÃÃo apenas nos estÃdios de maior tolerÃncia da cultura) e o sistema de rotaÃÃo de culturas feijÃo-de-corda/girassol, visando o uso sustentÃvel de Ãgua salina na agricultura irrigada. O experimento com feijÃo-de-corda foi conduzido no campo na estaÃÃo seca de 2011, e obedeceu ao delineamento em blocos ao acaso, com treze tratamentos e cinco repetiÃÃes. Os tratamentos consistiram de: T1: Ãgua de baixa salinidade (A1), durante todo o ciclo; T2, T3 e T4: Ãgua com CE de 2,2 (A2), 3,6 (A3) e 5,0 (A4) dS m-1, durante todo o ciclo, T5, T6 e T7: Ãgua com CE de 2,2, 3,6 e 5,0 dS m-1 na fase final do ciclo, T8, T9 e T10: Uso cÃclico de A1 e A2; A1 e A3 e A1 e A4, iniciando com A1 no plantio; T11, T12 e T13: Ãgua com CE de 2,2, 3,6 e 5,0 dS m-1 11 dias apÃs o plantio atà o final do ciclo, respectivamente. Para verificar o efeito residual de Ãgua salina aplicada durante o experimento com o feijÃo-de-corda, foi cultivado na estaÃÃo chuvosa de 2012 o girassol nas mesmas parcelas que foram cultivadas com o feijÃo-de-corda, utilizando irrigaÃÃo suplementar com Ãgua de baixa salinidade (A1). Os valores de CEa para o rejeito de dessalinizaÃÃo na regiÃo de Pentecoste variaram de 4,2 a 7,6 dS m-1, representando riscos para o ambiente, sendo que a maior parte do rejeito gerado à utilizada para alimentaÃÃo animal e a grande maioria da populaÃÃo nÃo tem conhecimento se o rejeito causa algum dano à saÃde humana ou ao meio ambiente. Os resultados dos experimentos de campo demonstraram que a aplicaÃÃo de Ãgua salina durante todo o ciclo do feijÃo-de-corda ao nÃvel de 5,0 dS m-1 e apÃs a 11 dias do plantio atà o final do ciclo inibe as trocas gasosas foliares, a extraÃÃo de nutrientes, o crescimento vegetativo e a produtividade da cultura, enquanto as estratÃgias de irrigaÃÃo com Ãgua salina na fase final do ciclo (floraÃÃo e frutificaÃÃo) e de forma cÃclica nÃo afetam de forma negativa essas variÃveis. AlÃm disso, essas estratÃgias permitiram uma economia de 34 a 47% de Ãgua de baixa salinidade utilizada na irrigaÃÃo. Ocorreu acÃmulo de sais no solo durante o cultivo do feijÃo-de-corda nos tratamentos em que se utilizou Ãgua de elevada salinidade. No entanto, o uso de estratÃgias de manejo como a aplicaÃÃo alternada de Ãguas de baixa e alta salinidade ao longo do ciclo da cultura e aplicaÃÃo da Ãgua salina apenas no estÃdio final reduziu o impacto sobre o solo. A irrigaÃÃo com Ãgua do canal (A1) com CE de 0,5 dS m-1 durante o cultivo do girassol promoveu a lixiviaÃÃo do excesso de sais no solo no final do cultivo, mas o total de chuvas antes do plantio nÃo foi suficiente para eliminar completamente o efeito residual da salinidade nesta cultura.The world population growth and increasing demand for water to meet household consumption and other sectors of the economy, have awakened for the use of alternative sources or water of inferior quality, such as saline water and wastewater. The aim of this study was a preliminary assessment of the situation of desalination plants installed by the State Government of Ceara in the region of Pentecoste, CearÃ, and then to evaluate irrigation management strategies (cyclic use of saline water, mixture of water of different salinities and use only in stages of tolerant phase of crop) and the system of crop rotation cowpea/sunflower, aiming at the sustainable use of saline water in irrigated agriculture. The experiment with the cowpea was conducted in the dry season of 2011, and followed the randomized block design, with thirteen treatments and five replications. The treatments were: T1: low salinity water (A1), throughout the cycle, T2, T3 and T4: Water with CE 2.2 (A2), 3.6 (A3) and 5.0 (A4) dS m-1, throughout the cycle, T5, T6 and T7: Water with EC of 2.2, 3.6 and 5.0 dS m-1 in the final phase of the cycle, T8, T9 and T10: Use cyclic A1 and A2, A1 and A3 and A1 and A4, starting with A1 at sowing, T11, T12 and T13: Water of EC of 2.2, 3.6 and 5.0 dS m-1 after germination until the end of cycle. To verify the residual effect of saline water applied during the experiment with the cowpea, sunflower was grown in the rainy season of 2012 in the same plots that were cultivated with cowpea, using supplementary irrigation with water of low salinity. The EC of the desalination waste in the region of Pentecoste ranged from 4.2 to 7.6 dS m-1, representing a risk for the environment, where much of the waste generated is used to feed the vast majority of population is not aware if the reject cause any harm to human health or to the environment. The results of field experiments showed that the use of saline water during the entire cycle of the cowpea up to the level of 5.0 dS m-1 and after germination until the end of the cycle inhibits leaf gas exchange, extraction of nutrients, plant growth and crop yield, while the strategies of irrigation with saline water in the final phase of the crop cycle (flowering and fruiting) and cyclically not negatively affect these variables. Further, these strategies allow a saving 34-47% water of low salinity used for irrigation. There was accumulation of salts in the soil for the cultivation of cowpea of the treatments which used water of high salinity. However, the use of strategies for managing the application of alternating high and low water salinity crop cycle and application of the salt water only in the final stage reduced the impact on soil. The irrigation water of low salinity (0.5 dS m-1) promoted excessive leaching of salts in the soil at the end of sunflower cultivation, but the amount of rainfall before seeding was not sufficient to completely eliminate the residual effect of salinity in the crop.
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Proust, Katrina Margaret, and kproust@cres10 anu edu au. "Learning from the past for sustainability: towards an integrated approach." The Australian National University. Centre for Resource and Environmental Studies, 2004. http://thesis.anu.edu.au./public/adt-ANU20050706.140605.
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The task of producing policies for the management of Earth’s natural resources is a problem of the gravest concern worldwide. Such policies must address both responsible use in the present and the sustainability of those finite resources in the future. Resources are showing the adverse results of generations of exploitation, and communities fail to see the outcomes of past policies that have produced, and continue to produce, these results. They have not learned from past policy failures, and consequently fail to produce natural resource management (NRM) policies that support sustainable development.¶
It will be argued that NRM policy makers fail to learn from the past because they do not have a good historical perspective and a clear understanding of the dynamics of the complex human-environment system that they manage. It will also be argued that historians have not shown an interest in collaborating with policy makers on these issues, even though they have much to offer. Therefore, a new approach is proposed, which brings the skills and understanding of the trained historian directly into the policy arena.¶
This approach is called Applied Environmental History (AEH). Its aims are to help establish an area of common conceptual ground between NRM practitioners, policy makers, historians and dynamicists; to provide a framework that can help NRM practitioners and policy makers to take account of the historical and dynamical issues that characterise human-environment relationships; and to help NRM practitioners and policy makers improve their capacity to learn from the past.
Applied Environmental History captures the characteristics of public and applied history and environmental history. In order to include an understanding of feedback dynamics in human-environment systems, it draws on concepts from dynamical systems theory. Because learning from the past is a particular form of learning from experience, AEH also draws on theories of cognitive adaptation.¶
Principles for the application of AEH are developed and then tested in an exploratory study of irrigation development that is focused on the NRM issue of salinity. Since irrigation salinity has existed for centuries, and is a serious environmental problem in many parts of the world, it is a suitable NRM context in which to explore policy makers' failure to learn from the past. AEH principles guide this study, and are used, together with insights generated from the study, as the basis for the design of AEH Guidelines.
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Costa, Maria Eugênia da. "Irrigação com águas de níveis de salinidade diferentes aplicadas de acordo com a fase de desenvolvimento da mamoeira." Universidade Federal Rural do Semi-Árido, 2012. http://bdtd.ufersa.edu.br:80/tede/handle/tede/467.
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Previous issue date: 2012-02-27Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
The castor bean (Ricinus communis L.), due to its ability to produce satisfactorily under conditions of low rainfall is an alternative of great importance for the Brazilian semiarid region. Currently, however, has been stimulated their irrigated, since, in many cases, irrigation is the only way to ensure the production, mainly in tropical regions of hot, dry climate, which predominates in northeast Brazil. This experiment was conducted to evaluate the influence of irrigation with saline water on growth and yield of castor (BRS Energy), and monitor the evolution of some soil chemical properties along the crop cycle. The experimental design was randomized blocks with six treatments and five repetitions. The treatments consisted of combinations of phases of development of castor bean (vegetative and reproductive), and water salinities (0.55, 2.16, 3.53 dS m-1). Evaluations of growth (plant height, stem diameter and leaf number) were evaluated at 20, 40, 60, 80, 100 days after sowing. The soil samples were carried out concomitantly with the assessments of growth, the layers 0-0.10; 0.10 to 0.30, 0.30-0.50 m. The soil chemical properties were evaluated exchangeable sodium, exchangeable sodium percentage, electrical conductivity and pH. We also evaluated yield components, number and length of the racemes, number and weight of fruit, productivity and total productivity of the racemes. The results indicated that irrigation with saline water throughout the cycle of the castor bean productivity decreased approximately 26% compared with the water of low salinity. The adoption of management of water salinities increased sharply attributes Na +, PST and CE, but the conditions studied there was no negative impacts on the salinity / sodicity
A mamoneira (Ricinus communis L), por apresentar capacidade de produzir satisfatoriamente sob condições de baixa precipitação é uma alternativa de grande importância para o semiárido brasileiro. Porém, atualmente tem sido estimulado o seu cultivo irrigado, uma vez que, em muitas situações, a irrigação é a única maneira de garantir a produção, principalmente em regiões tropicais de clima quente e seco, predominante no nordeste brasileiro. Esse experimento foi realizado com o objetivo de avaliar a influência da irrigação com água salina no crescimento e na produção da mamona (cultivar BRS Energia), além de monitorar a evolução de alguns atributos químicos do solo ao longo do ciclo da cultura. O delineamento experimental foi em blocos casualizados com seis tratamentos e cinco repetições. Os tratamentos resultaram da combinação entre fases de desenvolvimento da mamona (vegetativa e reprodutiva) e águas de diferentes salinidades (0,55; 2,16; 3,53 dS m-1). As avaliações de crescimento (altura de planta, diâmetro de caule e número de folhas) foram realizadas aos 20; 40; 60; 80; 100 dias após a semeadura. As coletas de solo foram realizadas concomitantemente às avaliações de crescimento, nas camadas 0-0,10; 0,10-0,30; 0,30-0,50m. Os atributos químicos do solo avaliados foram sódio trocável, percentagem de sódio trocável, condutividade elétrica e pH. Também foram avaliados alguns componentes de produção, como número e comprimento dos racemos, número e peso dos frutos, produtividade dos racemos e produtividade total. Os resultados indicaram que a irrigação com água salina durante todo o ciclo da mamoneira diminuiu a produtividade em aproximadamente 26%, quando comparado com a agua de baixa salinidade. A adoção do manejo das águas de diferentes salinidades aumentou acentuadamente os atributos Na+, PST e CE, porém nas condições estudadas não houve impactos negativos quanto a salinidade/sodicidade do solo
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NASCIMENTO, Hugo Henrique Costa do. "Mecanismos fisiológicos e bioquímicos em mudas de jatobá (Hymenaea courbaril L.), sob condições adversas." Universidade Federal Rural de Pernambuco, 2013. http://www.tede2.ufrpe.br:8080/tede2/handle/tede2/5501.
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Among the tree species native to Brasil, the jatoba (Hymenaea courbaril L.) has been the subject of several studies addressing its potential in carbon sequestration, as well as restoration of degraded environments. However, the physiological responses on the water stress, salinity and nutritional plants jatoba are practically unknown. In order to clarify some of the relationships between these processes, the present study aimed to evaluate the effects of suppression water, salinity and omission of N, P and K in the physiological behavior of seedlings jatoba. To conduct this work were conducted three experiments in the greenhouse of the Laboratory of Plant Physiology, Department of Biology, Universidade Federal Rural de Pernambuco, Recife, Brazil. Therefore, the plants were propagated from seeds collected in two regions of occurrence of the species, in the Pernambuco State. The first trial addressed the effects of water stress by suppressing irrigation and later irrigation, while for the evaluation of salt stress, we conducted a test checking the deleterious effects of the incremental addition of NaCl (0, 50 and 100 mM), hydroponically, and finally the effects of omission of N, P and K were evaluated in the third trial. In all experiments, the parameters were evaluated for growth, gas exchange, water relations, photosynthetic pigments, quantum efficiency of photosystem II and biochemical aspects by quantification of compatible solutes. The results of this study infers that jatoba seedlings have a tendency to accumulation of photosynthetic pigments and organic solutes, mainly proline as the main features of coping suppression watering. Fact allowing rapid reestablishment of their metabolism after rehydration in the early stage of development. Another fact that should be emphasized is that there is evidence that they bear up to 12 days of drought without compromising your metabolism. Information that may be useful to reforestation programs and producing seedlings of the species. Regarding the behavior versus salinity, it is concluded that the jatobá plants osmotically adjusted, once accumulated organic solutes that promote the increase of leaf turgidity, resulting in the continued growth and stabilization of gas exchange, even after subjection to stress severe salt (100 mM). Among the variables is recommended to evaluate the levels of chloride, sodium and potassium in the leaves, stems and roots for the characterization of the state of tolerance to salinity changes of jatoba. Regarding the behavior of seedlings by omission of N, P and K was observed that N was the most limiting macronutrient development of jatoba plants, suggesting that the nutritional requirement regarding macronutrients of that species obeying the order of decreasing N> P> K. It is hoped that the results obtained in this study may elucidate the main mechanisms used by jatobá to tolerate abiotic stresses and that information is useful for establishing adequate management exploitation of the species, since the ease of obtaining seedlings and its occurrence in areas prone to various environmental stresses, enhance its use in the processes of reclamation and / or reforestation.
Dentre as espécies arbóreas nativas do Brasil, o jatobá (Hymenaea courbaril L.) tem sido alvo de diversos estudos abordando sua potencialidade na fixação de carbono, bem como na recuperação de ambientes degradados. No entanto, as respostas fisiológicas ante os estresses hídrico, salino e nutricional em plantas de jatobá ainda apresentam lacunas a serem esclarecidas. Visando elucidar algumas desses pontos, o presente estudo objetivou avaliar os efeitos da supressão hídrica, salinidade e omissão de N, P e K no comportamento fisiológico de mudas de jatobá. Para a realização desse trabalho foram conduzidos três ensaios em casa de vegetação do Laboratório de Fisiologia Vegetal do Departamento de Biologia da Universidade Federal Rural de Pernambuco, Recife, Brasil. Para a montagem dos experimentos foram utilizadas as mudas obtidas de sementes colhidas em duas regiões de ocorrência da espécie, situadas no Agreste pernambucano. No primeiro ensaio foram avaliados os efeitos do estresse hídrico por meio da supressão de rega e posterior reirrigação; já para a análise do comportamento das mudas sob estresse salino, conduziu-se um ensaio verificando os efeitos deletérios da adição crescente de NaCl (0, 50 e 100 mM), em sistema hidropônico; por fim, os efeitos da omissão de N, P e K foram avaliados no terceiro ensaio. Em todos os experimentos, foram avaliados as variáveis de crescimento, trocas gasosas, relações hídricas, pigmentos fotossintéticos, eficiência quântica do fotossistema II e aspectos bioquímicos pela quantificação de solutos compatíveis. Os resultados desta pesquisa permitem inferir que mudas de jatobá acumulam pigmentos fotossintéticos e solutos orgânicos, principalmente a prolina, como as principais características de enfrentamento a supressão de rega. Fatos que possibilitam um rápido reestabelecimento de seu metabolismo após a reidratação na fase inicial do desenvolvimento. Outro fato que merece ser destacado é que há indícios de que as mesmas suportem até 12 dias de estiagem sem comprometer seu metabolismo. Informação que pode ser útil a programas de reflorestamento e produtores de mudas da referida espécie. Quanto ao comportamento ante a salinidade, conclui-se que as plantas de jatobá se ajustaram osmoticamente, uma vez que acumularam solutos orgânicos que promoveram a elevação da turgescência foliar, resultando na continuidade do crescimento e estabilização das trocas gasosas, mesmo após submissão a um estresse salino severo (100 mM). Dentre as variáveis estudadas recomenda-se a avaliação dos teores de cloreto, sódio e potássio nas folhas, caules e raízes para a caracterização do estado de tolerância de mudas de jatobá à salinidade. Em relação ao comportamento das mudas mediante omissão de N, P e K observou-se que o N foi o macronutriente mais limitante ao desenvolvimento de plantas de jatobá, sugerindo que o requerimento nutricional quanto aos macronutrientes da referida espécie obedeça à ordem decrescente de N>P>K. Os resultados obtidos nesta pesquisa indicam os principais mecanismos utilizados pelo jatobá para tolerar estresses abióticos. Essas Informações podem ser úteis para o estabelecimento de um manejo adequado à exploração da espécie, uma vez que a facilidade de obtenção de mudas aliada a ocorrência em áreas propensas a estresses ambientais diversos, potencializam a utilização do jatobá nos processos de recuperação de áreas degradadas e/ou reflorestamentos.
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Silva, Aijânio Gomes de Brito. "Efeito da irrigação com efluente de esgoto rico em sódio em propriedades químicas e físico-hídricas de um Argissolo e produtividade de capim Tifton 85 no município de Lins." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/11/11140/tde-01072013-085609/.
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O uso de efluente de estação de tratamento de esgoto (EETE) na agricultura irrigada pode ser uma estratégia alternativa de fornecimento de água e nutrientes para culturas agrícolas. Entretanto se realizado por longos períodos pode adicionar grandes quantidades de sódio ao solo o que poderia levar a degradação de suas propriedades e impacto em aspectos agronômicos de capim Tifton 85. Esse trabalho consistiu de dois objetivos: i) avaliar os efeitos da irrigação com efluente rico em sódio durante mais de oito anos em propriedades químicas e físico-hídricas de um Argissolo Vermelho. Para isso foram estabelecidos três tratamentos avaliados nas profundidades de 0,05-0,15 (P1), 0,25-0,35 (P2) e 0,70-0,80 m (P3): SI - cultivo de capim sem adubação e sem irrigação; A100 - cultivo irrigado com água de abastecimento sódica e adubado com 520,0 kg ha-1 ano-1 de nitrogênio; E66 - cultivo irrigado com EETE e adubado com 343,2 kg ha-1 ano-1 de nitrogênio. Foram determinados: pH do solo (em água e CaCl2), condutividade elétrica do extrato aquoso do solo (CE1:1), concentração de sódio (Na+), potássio (K+), cálcio (Ca2+), magnésio (Mg2+), alumínio (Al3+), carbono (C) e nitrogênio (N) do solo, com posterior cálculo de soma de bases (SB), capacidade de troca catiônica (CTC), saturação por bases (V) e percentagem de sódio trocável (PST); densidade do solo (?), argila dispersa em água (ADA), condutividade hidráulica do solo saturado (Ksat), curva de retenção da água no solo (CR), porosidade do solo (?) e distribuição do tamanho dos poros; ii) avaliar os efeitos da irrigação com efluente rico em sódio durante mais de oito anos em aspectos agronômicos de capim Tifton 85. Para alcançar o segundo objetivo foi estabelecido além do SI, A100 e E66, mais quatro tratamentos: A0 - cultivo de capim sem adubação e irrigado com água de abastecimento sódica; E0, E33 e E100 - cultivo de capim irrigado com EETE e adubado com 0, 171,6 e 520,0 kg ha-1 ano-1 de nitrogênio, respectivamente. Foram determinados: produtividade de massa seca estacional (MS-Estacional), anual (MS-Anual) e acumulação estacional e anual de nitrogênio (N-MS), potássio (K-MS) e sódio (Na-MS) no tecido vegetal de capim Tifton 85. Houve alterações nas propriedades químicas e físico-hídricas do solo em função dos tratamentos e profundidades. Na P1 o E66 aumentou a CE1:1, a densidade do solo, o conteúdo de água residual e diminuiu a concentração de Mg2+ e conteúdo de água de saturação. Já o A100 reduziu a concentração de K+ e Mg2+, o conteúdo de água de saturação e aumentou a densidade do solo e o conteúdo de água residual. Na P2 o E66 aumentou o pH-H2O e a CE1:1, o conteúdo de água de saturação e o conteúdo residual. O A100 aumentou o pH-H2O, o Na+, o PST, a argila dispersa em água, o conteúdo de água de saturação e o conteúdo residual e diminuiu o C e N. Na P3 o E66 aumentou apenas o pH-H2O e o conteúdo de água residual e reduziu o conteúdo de água de saturação. O A100 aumentou o conteúdo de água de saturação, o conteúdo de água residual e a mesoporosidade. As propriedades do solo da P2 parecem ser as mais afetadas pelos efeitos do sódio decorrentes, principalmente, do uso de irrigação com água sódica. As produtividades de MS e acumulação de N-MS e K-MS foram superiores nos tratamentos E66, E100 e A100 e não foram reduzidas ao longo destes anos. A acumulação de Na-MS foi proporcional à produtividade, mas o capim passou a acumular um pouco menos sódio. Na estação chuvosa a MS de capim representou cerca de 72% da MS-Anual, sendo influenciada fortemente pelo período de estacionalidade.The use of treated sewage effluent (TSE) in irrigated agriculture can be an alternative strategy to supply water and nutrients to crops. However if applied for long periods of time, it can add large amounts of sodium to the soil, resulting in soil properties degradation and impacts on agronomic aspects Tifton 85 Bermudagrass. The objectives of this work were: i) evaluate the effect of irrigation with sodium rich effluent for more than eight years on chemical, physical and hydraulic properties of an Ultisol. For this were established three treatments (WI - growing grass without fertilization or irrigation ; FW100 - irrigation with sodic fresh water supply and fertilized with 520.0 kg ha-1 year-1 nitrogen; E66 - irrigation with TSE and fertilized with 343.2 kg ha-1 year-1 nitrogen) The effects were evaluated at different depths (D1: 0.5-0.15, D2: 0.25-0.35 and D3: 0.70-0.80 m), determining: soil pH (in water and CaCl2), soil electrical conductivity of the aqueous extract (EC1:1) sodium concentration (Na+), potassium (K+), calcium (Ca2+), magnesium (Mg2+), aluminum (Al3+), soil carbon (C) and soil nitrogen (N), with subsequent calculation of sum of bases (SB), cation exchange capacity (CEC), base saturation (V) and exchangeable sodium percentage (ESP); bulk density (?), water dispersible clay (WDC), saturated hydraulic conductivity (Ksat), soil water retention curve (SWRC), soil porosity (?) and pore size distribution. Another objective was to evaluate the effect of irrigation with sodium rich effluent for more than eight years on agronomic aspects of Tifton 85 Bermudagrass. In addition to WI, FW100 and E66 treatments were established another four treatments (FW0 - growing grass without fertilizer and irrigated with sodic water supply; E0, E33 and E100 - growing grass irrigated with TSE and fertilized with 0, 171.6 and 520.0 kg ha-1 year-1 nitrogen, respectively) and determined the productivity of seasonal dry matter (Seasonal-DM), annual (Annual-DM) and nitrogen (N-DM), potassium (K-DM) and sodium (Na-DM) seasonal accumulation and annual in the plant tissue of Tifton 85 Bermudagrass. There were changes in chemical, physical and hydraulic soil properties as a function of treatments and depths. In the D1 the E66 treatment increased CE1:1, the bulk density, the residual water content and decreased the concentration of Mg2+, water content at saturation. FW100 reduced the concentration of K+ and Mg2+, the water content at saturation and increased soil bulk density and residual water content. In the D2, the E66 treatment increased pH-H2O and CE1:1, the water content at saturation and residual water content. The FW100 increased pH-H2O, Na+, ESP, water dispersible clay , the content of water saturation and residual contents and decreased C and N. In the D3 the E66 only increased the pH-H2O and residual water content and reduced water content saturation. The FW100 increased the water content at saturation point, residual water content and mesoporosity. The soil properties of D2 aparently are more affected than other depths by the effects of sodium, mainly from the use of irrigation water with sodium. The DM, N-DM and, K-DM were higher in the treatments E66, E100 and FW100 and there were not observed reductions over the years. The accumulation Na-DM was proportional to productivity, but the grass began to accumulate less sodium. In the rainy season the grass DM accounted for approximately 72% of Annual-DM, being strongly influenced by seasonality period.
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Costa, Djeson Mateus Alves da. "Impactos do estresse salino e da cobertura morta nas caracter?sticas qu?micas do solo e no desenvolvimento do amaranto." Universidade Federal do Rio Grande do Norte, 2007. http://repositorio.ufrn.br:8080/jspui/handle/123456789/15870.
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Previous issue date: 2007-11-30Availability of good quality water has been reduced vertiginously, over the last decade, in the world. In some regions, the water resources have high concentration of the dissolved salts, these characteristics of the water make it s use impossible. Water quality can be a limitation for irrigated agriculture, principally in regions of arid or semiarid climate where the water resources are generally saline and are exposed at high evaporation ratio. For that reason, precipitation of the salts occurs near the soil surface and those salts themselves cumulate in the vegetal tissue, reducing the soil fertility and crop production. The adoption of tolerant crop to the water salinity and soil salinity, adaptable to the climatic conditions is other emergent necessity. This work had the goal of studying the effects of four salinity levels of the irrigation water salinity and use of mulch, dried leaves of Forest mangrove (Acacia mangiumWilld), in cultivated soil with amaranth (Amaranthus cruentus, BRS Alegria variety), in greenhouse. It was utilized the transplant of plants to PVC columns, containing 30 kg of silty loam soil, 10 days after emerging, with space of 50 x 50 cm between lines. Treatments were composed by combination of four levels of salinity (0.147; 1.500; 3.000 e 4.500 dS m-1), obtained by addition NaCl (commercial) to irrigation water and soil with and without protection, by mulch. A factorial system 4 x 2 was used with four repetitions, totalizing 32 parcels. The concentrations of nutrients in soil solution have been evaluated, in the dry matter of the vegetal tissue (roots, stem, leaves and raceme residue), at the end of the vegetative cycle. The use of soil protection reduced time for the beginning inflorescence of plants, at the same time, the increase of the salinity delayed this phase of amaranth development. The use of the mulch effectively increased the height, stem diameter, area of the larger leaf, humidity and dry matter content and amaranth grain production. The vegetal species showed salinity tolerance to experimented levels. The adopted treatments did not affect the pH values, exchangeable cation contents, electrical conductivity of soil solution (EC1:5) and saturated extract (ECSE), and Ca+2, Mg+, Fe+2 and Mn+2 contents, in the soil solution. The increase of the salinity concentration in the irrigation water inhibited the mineralization process of the organic matter (OM) and, consequently, the efficiency in the it?s utilization by plants, at the same time, produced increase in the values of the exchangeable sodium percentage (ESP), sodium adsorption ratio (SAR) and potassium adsorption ratio (PAR), in the soil solution. Therefore, the use of the mulch did not affect the first three parameters. The protein and nutrient contents: K+, Ca+2, P, Mg+2 e Cu+2, in amaranth grains, were improved by tillage condition. The raceme residues showed chemical/nutritional composition that makes advantageous its application in animal ration. In this context, it follows that amaranth tolerate the saline stress, of the irrigation water, until 4.500 dS m-1, temperature and relative humidity of the air predominant in the experimental environment
A disponibilidade de ?gua de boa qualidade tem diminu?do vertiginosamente nas ?ltimas d?cadas, em todo o mundo. Em algumas regi?es os recursos h?dricos dispon?veis apresentam altos teores de sais dissolvidos, inviabilizando a sua utiliza??o. A qualidade da ?gua pode ser um fator limitante para a agricultura irrigada, principalmente nas regi?es de clima ?rido ou semi-?rido onde os recursos h?dricos s?o geralmente salinos e se encontram expostos a altas taxas de evapora??o que ocasiona a precipita??o de sais na superf?cie do solo e ac?mulo no tecido vegetal, diminuindo, respectivamente, a fertilidade e o rendimento da cultura. Logo, a ado??o de cultivares tolerantes ? salinidade da ?gua de irriga??o e do solo, assim como, resistentes ?s condi??es clim?ticas ? outra necessidade emergente na atualidade. Este trabalho teve o objetivo de estudar os efeitos de quatro n?veis de salinidade da ?gua de irriga??o e da cobertura morta, folhas secas de ac?cia (Acacia mangiumWilld), em solo cultivado com amaranto (Amaranthus cruentus, variedade BRS Alegria), conduzido em casa de vegeta??o. Foi utilizado o sistema de forma??o de mudas, transplantadas 10 dias ap?s emerg?ncia para colunas de PVC contendo 30 kg de solo franco-siltoso, no espa?amento de 0,50 x 0,50 m. Os tratamentos foram compostos pela combina??o de quatro n?veis de salinidade (0,147; 1,500; 3,000 e 4,500 dS m-1), obtidos pela adi??o de NaCl (comercial) ? ?gua de irriga??o, e solo com e sem prote??o por cobertura morta. Utilizou-se um arranjo fatorial 4x2 com quatro repeti??es, perfazendo um total de 32 parcelas. Foram avaliados os teores de nutrientes presentes na solu??o do solo e na mat?ria seca do tecido vegetal (ra?zes, caule, folhas, gr?os e res?duo de pan?cula), ao final do ciclo vegetativo. O uso de prote??o do solo reduziu o tempo para o in?cio da flora??o das plantas, ao mesmo tempo em que o aumento da salinidade retardou essa fase do desenvolvimento do amaranto. O uso da prote??o do solo proporcionou aumentos significativos na altura, no di?metro de caule, na ?rea da folha mais desenvolvida, na quantidade de mat?ria fresca e seca e na produ??o de gr?os do amaranto. A esp?cie vegetal apresentou toler?ncia ? salinidade, para os n?veis experimentados. Os tratamentos adotados n?o afetaram os valores de pH, capacidade de troca de c?tions (CTC), condutividade el?trica da solu??o do solo (CE1:5) e extrato saturado (CEES), e teores de Ca+2, Mg+2, Fe+2 e Mn+2, na solu??o de solo. O aumento da concentra??o salina na ?gua de irriga??o inibiu o processo de mineraliza??o da mat?ria org?nica (MO) e, consequentemente, a efici?ncia de seu aproveitamento pelas plantas, ao mesmo tempo em que provocou aumento nos valores da porcentagem de s?dio troc?vel (PST), da raz?o de adsor??o de s?dio (RAS) e de pot?ssio (RAP) na solu??o de solo. No entanto, o uso de prote??o do solo n?o afetou os tr?s primeiros fatores. Os teores de prote?na bruta e dos nutrientes: K+, Ca+2, P, Mg+2 e Cu+2, nos gr?os do amaranto, foram beneficiados pelas condi??es de cultivo. Os res?duos de pan?culas apresentaram composi??o qu?mica/nutricional que favorece a sua utiliza??o como complemento para ra??o animal. Neste contexto, pode-se concluir que o amaranto ? tolerante ao estresse salino, da ?gua de irriga??o, at? o n?vel de 4,500 dS m-1 e ?s condi??es de temperatura e umidade relativa do ar predominantes no ambiente experimental
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Neves, Antônia Leila Rocha. "Estratégias visando o uso sustentável de água salina em um ciclo de rotação cultural feijão-de-corda/girassol." reponame:Repositório Institucional da UFC, 2012. http://www.repositorio.ufc.br/handle/riufc/18787.
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NEVES, Antônia Leila Rocha.Estratégias visando o uso sustentável de água salina em um ciclo de rotação cultural feijão-de-corda/girassol. 2012. 159 f. : Tese (doutorado) - Universidade Federal do Ceará, Centro de Ciências Agrárias, Departamento de Engenharia Agrícola, Programa de Pós-Graduação em Engenharia Agrícola, Fortaleza-CE, 2015.Submitted by demia Maia (demiamlm@gmail.com) on 2016-08-01T16:31:10Z No. of bitstreams: 1 2015_tese_alrneves.pdf: 5244793 bytes, checksum: 9b9ea12c8d4f13c6be11e4de21f8c5db (MD5)
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The world population growth and increasing demand for water to meet household consumption and other sectors of the economy, have awakened for the use of alternative sources or water of inferior quality, such as saline water and wastewater. The aim of this study was a preliminary assessment of the situation of desalination plants installed by the State Government of Ceara in the region of Pentecoste, Ceará, and then to evaluate irrigation management strategies (cyclic use of saline water, mixture of water of different salinities and use only in stages of tolerant phase of crop) and the system of crop rotation cowpea/sunflower, aiming at the sustainable use of saline water in irrigated agriculture. The experiment with the cowpea was conducted in the dry season of 2011, and followed the randomized block design, with thirteen treatments and five replications. The treatments were: T1: low salinity water (A1), throughout the cycle, T2, T3 and T4: Water with CE 2.2 (A2), 3.6 (A3) and 5.0 (A4) dS m-1, throughout the cycle, T5, T6 and T7: Water with EC of 2.2, 3.6 and 5.0 dS m-1 in the final phase of the cycle, T8, T9 and T10: Use cyclic A1 and A2, A1 and A3 and A1 and A4, starting with A1 at sowing, T11, T12 and T13: Water of EC of 2.2, 3.6 and 5.0 dS m-1 after germination until the end of cycle. To verify the residual effect of saline water applied during the experiment with the cowpea, sunflower was grown in the rainy season of 2012 in the same plots that were cultivated with cowpea, using supplementary irrigation with water of low salinity. The EC of the desalination waste in the region of Pentecoste ranged from 4.2 to 7.6 dS m-1, representing a risk for the environment, where much of the waste generated is used to feed the vast majority of population is not aware if the reject cause any harm to human health or to the environment. The results of field experiments showed that the use of saline water during the entire cycle of the cowpea up to the level of 5.0 dS m-1 and after germination until the end of the cycle inhibits leaf gas exchange, extraction of nutrients, plant growth and crop yield, while the strategies of irrigation with saline water in the final phase of the crop cycle (flowering and fruiting) and cyclically not negatively affect these variables. Further, these strategies allow a saving 34-47% water of low salinity used for irrigation. There was accumulation of salts in the soil for the cultivation of cowpea of the treatments which used water of high salinity. However, the use of strategies for managing the application of alternating high and low water salinity crop cycle and application of the salt water only in the final stage reduced the impact on soil. The irrigation water of low salinity (0.5 dS m-1) promoted excessive leaching of salts in the soil at the end of sunflower cultivation, but the amount of rainfall before seeding was not sufficient to completely eliminate the residual effect of salinity in the crop.
O crescimento da população mundial e a crescente demanda de água para atender o consumo das famílias e os demais setores da economia, têm despertado para o aproveitamento de fontes alternativas ou águas de qualidade inferior, tais como as águas salinas e residuárias. O objetivo desse trabalho foi realizar uma avaliação preliminar sobre a situação dos dessalinizadores instalados pelo Governo do Estado do Ceará na região de Pentecoste, Ceará, e, em seguida, avaliar estratégias de manejo da irrigação (uso cíclico de água salina, mistura de fontes de água de diferentes salinidades e utilização apenas nos estádios de maior tolerância da cultura) e o sistema de rotação de culturas feijão-de-corda/girassol, visando o uso sustentável de água salina na agricultura irrigada. O experimento com feijão-de-corda foi conduzido no campo na estação seca de 2011, e obedeceu ao delineamento em blocos ao acaso, com treze tratamentos e cinco repetições. Os tratamentos consistiram de: T1: Água de baixa salinidade (A1), durante todo o ciclo; T2, T3 e T4: Água com CE de 2,2 (A2), 3,6 (A3) e 5,0 (A4) dS m-1, durante todo o ciclo, T5, T6 e T7: Água com CE de 2,2, 3,6 e 5,0 dS m-1 na fase final do ciclo, T8, T9 e T10: Uso cíclico de A1 e A2; A1 e A3 e A1 e A4, iniciando com A1 no plantio; T11, T12 e T13: Água com CE de 2,2, 3,6 e 5,0 dS m-1 11 dias após o plantio até o final do ciclo, respectivamente. Para verificar o efeito residual de água salina aplicada durante o experimento com o feijão-de-corda, foi cultivado na estação chuvosa de 2012 o girassol nas mesmas parcelas que foram cultivadas com o feijão-de-corda, utilizando irrigação suplementar com água de baixa salinidade (A1). Os valores de CEa para o rejeito de dessalinização na região de Pentecoste variaram de 4,2 a 7,6 dS m-1, representando riscos para o ambiente, sendo que a maior parte do rejeito gerado é utilizada para alimentação animal e a grande maioria da população não tem conhecimento se o rejeito causa algum dano à saúde humana ou ao meio ambiente. Os resultados dos experimentos de campo demonstraram que a aplicação de água salina durante todo o ciclo do feijão-de-corda ao nível de 5,0 dS m-1 e após a 11 dias do plantio até o final do ciclo inibe as trocas gasosas foliares, a extração de nutrientes, o crescimento vegetativo e a produtividade da cultura, enquanto as estratégias de irrigação com água salina na fase final do ciclo (floração e frutificação) e de forma cíclica não afetam de forma negativa essas variáveis. Além disso, essas estratégias permitiram uma economia de 34 a 47% de água de baixa salinidade utilizada na irrigação. Ocorreu acúmulo de sais no solo durante o cultivo do feijão-de-corda nos tratamentos em que se utilizou água de elevada salinidade. No entanto, o uso de estratégias de manejo como a aplicação alternada de águas de baixa e alta salinidade ao longo do ciclo da cultura e aplicação da água salina apenas no estádio final reduziu o impacto sobre o solo. A irrigação com água do canal (A1) com CE de 0,5 dS m-1 durante o cultivo do girassol promoveu a lixiviação do excesso de sais no solo no final do cultivo, mas o total de chuvas antes do plantio não foi suficiente para eliminar completamente o efeito residual da salinidade nesta cultura.