Literatura científica selecionada sobre o tema "Water and nutrient use"
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Artigos de revistas sobre o assunto "Water and nutrient use"
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Kronvang, Brian, Frank Wendland, Karel Kovar e Dico Fraters. "Land Use and Water Quality". Water 12, n.º 9 (28 de agosto de 2020): 2412. http://dx.doi.org/10.3390/w12092412.
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The interaction between land use and water quality is of great importance worldwide as agriculture has been proven to exert a huge pressure on the quality of groundwater and surface waters due to excess losses of nutrients (nitrogen and phosphorous) through leaching and erosion processes. These losses result in, inter alia, high nitrate concentrations in groundwater and eutrophication of rivers, lakes and coastal waters. Combatting especially non-point losses of nutrients has been a hot topic for river basin managers worldwide, and new important mitigation measures to reduce the input of nutrients into groundwater and surface waters at the pollution source have been developed and implemented in many countries. This Special Issue of the Land use and Water Quality conference series (LuWQ) includes a total of 11 papers covering topics such as: (i) nitrogen surplus; (ii) protection of groundwater from pollution; (iii) nutrient sources of pollution and dynamics in catchments and (iv) new technologies for monitoring, mapping and analysing water quality.
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Ikkonen, Elena, Svetlana Chazhengina e Marija Jurkevich. "Nutrient and Water Use Efficiency at Leaf Level of Cucumber Plants under Contrasting Soil Nutrient and Lignosulfonate Level". Biology and Life Sciences Forum 4, n.º 1 (30 de novembro de 2020): 25. http://dx.doi.org/10.3390/iecps2020-08611.
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To reduce the use of commercial conventional inorganic fertilizers, the possibility of using pulp and paper industry wastes in agriculture as an alternative source of nutrients has recently been under study and discussion. This work aimed to evaluate the effect of sodium lignosulfonate application to soil on photosynthetic leaf nutrient (N, P, K, Ca, Mg, Fe, and Mn) and water use efficiency. A pot culture experiment was conducted with cucumber seedlings using five lignosulfonate concentrations (0, 1, 2.5, 5, and 10 vol. %) in sandy soil under sufficient or low nutrient availability for plants. The impact of nutrient availability on plant physiological traits was stronger than the lignosulfonate impact. Under the condition of sufficient nutrient availability, the lignosulfonate application decreased N, P, K, Ca, Mg, and Fe use efficiency, increased Mn use efficiency, and did not change water use efficiency. The decrease in nutrient use efficiency was connected with both photosynthetic rate decrease and leaf nutrient content increase. The decline in soil nutrient availability caused a decrease in nutrient and water use efficiency. Under low nutrient availability, soil lignosulfonate tended to increase nutrient and water use efficiency, but it was not successful in eliminating the negative effects of soil nutrient deficiency on plant growth, photosynthetic processes, and efficiency of nutrient use.
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Katayama, Noboru, Kobayashi Makoto e Osamu Kishida. "An aquatic vertebrate can use amino acids from environmental water". Proceedings of the Royal Society B: Biological Sciences 283, n.º 1839 (28 de setembro de 2016): 20160996. http://dx.doi.org/10.1098/rspb.2016.0996.
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Conventional food-web theory assumes that nutrients from dissolved organic matter are transferred to aquatic vertebrates via long nutrient pathways involving multiple eukaryotic species as intermediary nutrient transporters. Here, using larvae of the salamander Hynobius retardatus as a model system, we provide experimental evidence of a shortcut nutrient pathway by showing that H. retardatus larvae can use dissolved amino acids for their growth without eukaryotic mediation. First, to explore which amino acids can promote larval growth, we kept individual salamander larvae in one of eight different high-concentration amino acid solutions, or in control water from which all other eukaryotic organisms had been removed. We thus identified five amino acids (lysine, threonine, serine, phenylalanine, and tyrosine) as having the potential to promote larval growth. Next, using 15 N-labelled amino acid solutions, we demonstrated that nitrogen from dissolved amino acids was found in larval tissues. These results suggest that salamander larvae can take up dissolved amino acids from environmental water to use as an energy source or a growth-promoting factor. Thus, aquatic vertebrates as well as aquatic invertebrates may be able to use dissolved organic matter as a nutrient source.
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Goddek, Simon, e Karel J. Keesman. "Improving nutrient and water use efficiencies in multi-loop aquaponics systems". Aquaculture International 28, n.º 6 (12 de setembro de 2020): 2481–90. http://dx.doi.org/10.1007/s10499-020-00600-6.
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Abstract The sustainable development of agricultural systems where nutrients and water are recycled to a high degree is of enormous importance. Traditional aquaponics, where fish and plants are cultivated in one recirculating system, addresses these ecological challenges, but still struggles with its economical feasibility. Decoupled multi-loop aquaponics systems, in which the aquaculture and hydroponics subsystems are running autonomously, proved that they can keep up with the productivity of state-of-the-art hydroponics systems or even outscore them. Yet, a problem of such decoupled aquaponics systems was that plants require a high nutrient concentration, whereas fish prefer rather a clean water. In practice, the opposite is happening as the nutrients are added to the aquaculture units through the feed. This paper optimizes a recent approach showing that desalination technologies, such as reverse osmosis, can play an important role in reversing the concentrations within such systems without killing beneficial plant growth–promoting rhizobacteria thermally. The proposed integrated systems approach has the potential to make both periodical nutrient and water discharges and excessive fertilizer supplementation obsolete that would otherwise be necessary to maintain good water quality for the fish and an optimal nutrient solution for the plants.
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Yan, Jing, Nathaniel A. Bogie e Teamrat A. Ghezzehei. "Root uptake under mismatched distributions of water and nutrients in the root zone". Biogeosciences 17, n.º 24 (17 de dezembro de 2020): 6377–92. http://dx.doi.org/10.5194/bg-17-6377-2020.
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Abstract. Most plants derive their water and nutrient needs from soils where the resources are often scarce, patchy, and ephemeral. It is not uncommon for plant roots to encounter mismatched patches of water-rich and nutrient-rich regions in natural environments. Such an uneven distribution of resources necessitates plant reliance on strategies for exploring and acquiring nutrients from relatively dry patches. We conducted a laboratory study that elucidates the biophysical mechanisms that enable this adaptation. The roots of tomato (Solanum lycopersicum) seedlings were laterally split and grown in two adjacent, hydraulically disconnected pots, which permitted precise control of water and nutrient applications to each compartment. We observed that the physical separation of water-rich and nutrient-rich compartments (one received 90 % water and 0 % nutrients and the other received 10 % water and 100 % nutrients) does not significantly stunt plant growth and productivity compared to two control treatments (control 1: 90 % water and 100 % nutrients versus 10 % water and 0 % nutrients; control 2: 50 % water and 50 % nutrients in each compartment). Specifically, we showed that soil dryness does not reduce nutrient uptake, vegetative growth, flowering, and fruiting compared to control treatments. We identified localized root proliferation in nutrient-rich dry soil patches as a critical strategy that enabled nutrient capture. We observed nocturnal rewetting of the nutrient-rich but dry soil zone (10 % water and 100 % nutrients) but not in the nutrient-free and dry zone of the control experiment (90 % water and 100 % nutrients). We interpreted the rewetting as the transfer of water from the wet to dry zones through roots, a process commonly known as hydraulic redistribution (HR). The occurrence of HR likely prevents the nutrient-rich soil from drying due to permanent wilting and the subsequent decline of root functions. Sustaining rhizosphere wetness is also likely to increase nutrient mobility and uptake. Lack of HR in the absence of nutrients suggests that HR is not entirely a passive, water-potential-gradient driven flow. The density and size of root hairs appeared to be higher (qualitative observation) in the nutrient-rich and dry compartments than in the nutrient-free and dry compartments. We also observed organic coating on sand grains in the rhizosphere of the nutrient-rich and dry compartments. The observations are consistent with prior observations that root hairs and rhizodeposition aid rhizosphere wetting. These findings were synthesized in a conceptual model that explains how plants of dry regions may be adapted to mismatched resources. This study also suggests that separating the bulk of applied nutrients from the frequently irrigated soil region can increase nutrient use efficiency and curtail water pollution from intensive agricultural systems.
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Benmoussa, Mohamed, e Laurent Gauthier. "Modeling Nutrient Uptake and Prolonged Use of Nutrient Solutions in Soilless Tomato Culture". HortScience 30, n.º 4 (julho de 1995): 761F—761. http://dx.doi.org/10.21273/hortsci.30.4.761f.
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In soilless culture, the buffering capacity of the root environment for nutrients is low. This, combined with fluctuations of climatic factors and changes in nutrient uptake rates, can lead to nutrient imbalances. In order to achieve high yield and better quality, it is necessary to keep the nutrient concentrations in the root environment at the target levels. This requires frequent analysis and adjustments to the nutrient solution. Currently, leaching of the growing media or renewal of the nutrient solution is commonly used to avoid accumulation or depletion of nutrient in the root environment. However, this practice lowers the efficiency of fertilizers and can lead to the contamination of the ground water. One way to remedy to this problem is through the use of nutrients uptake models to track the composition of the nutrient solutions. The objective of this study was to develop such models. Such models can be used to maintain balanced nutrient solutions for longer periods. This can lead to reduced leaching and improved fertilizer use efficiency. Macronutrient (N, P, K, Ca, and Mg) uptake models were developed for tomato plants grown in an NFT system using data collected from experiments conducted in the Laval Univ. greenhouses. Analysis of the experimental results showed that the main factors affecting nutrients uptakes are light and transpiration.
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Benmoussa, Mohamed, e Laurent Gauthier. "Modeling Nutrient Uptake and Prolonged Use of Nutrient Solutions in Soilless Tomato Culture". HortScience 30, n.º 4 (julho de 1995): 761F—761. http://dx.doi.org/10.21273/hortsci.30.4.761.
Texto completo da fonteResumo:
In soilless culture, the buffering capacity of the root environment for nutrients is low. This, combined with fluctuations of climatic factors and changes in nutrient uptake rates, can lead to nutrient imbalances. In order to achieve high yield and better quality, it is necessary to keep the nutrient concentrations in the root environment at the target levels. This requires frequent analysis and adjustments to the nutrient solution. Currently, leaching of the growing media or renewal of the nutrient solution is commonly used to avoid accumulation or depletion of nutrient in the root environment. However, this practice lowers the efficiency of fertilizers and can lead to the contamination of the ground water. One way to remedy to this problem is through the use of nutrients uptake models to track the composition of the nutrient solutions. The objective of this study was to develop such models. Such models can be used to maintain balanced nutrient solutions for longer periods. This can lead to reduced leaching and improved fertilizer use efficiency. Macronutrient (N, P, K, Ca, and Mg) uptake models were developed for tomato plants grown in an NFT system using data collected from experiments conducted in the Laval Univ. greenhouses. Analysis of the experimental results showed that the main factors affecting nutrients uptakes are light and transpiration.
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Ikkonen, Elena, Svetlana Chazhengina e Marija Jurkevich. "Photosynthetic Nutrient and Water Use Efficiency of Cucumis sativus under Contrasting Soil Nutrient and Lignosulfonate Levels". Plants 10, n.º 2 (10 de fevereiro de 2021): 340. http://dx.doi.org/10.3390/plants10020340.
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To reduce the use of commercial conventional inorganic fertilizers, the possibility of using pulp and paper industry wastes in agriculture as an alternative source of nutrients is recently under study and discussion. This work aimed to evaluate the effect of sodium lignosulfonate application to soil on photosynthetic leaf nutrient (N, P, K, Ca, Mg, Fe, Mn, and Na) and water use efficiency. A pot culture experiment was conducted with cucumber seedlings, using five lignosulfonate concentrations (0, 1, 2.5, 5, and 10 vol. %) in sandy soil under sufficient or low nutrient availability for plants. The impact of nutrient availability on the plants’ physiological traits was stronger than the lignosulfonate impact. Under sufficient nutrient availability, the lignosulfonate application resulted in decreased photosynthetic N, P, K, Ca, Mg, Fe, and Na use efficiency. Cucumber growth and development, and photosynthetic nutrient, water, and light use efficiency were significantly reduced with a nutrient deficiency. The sodium lignosulfonate application was not successful in eliminating the negative effects of nutrient deficit on cucumber seedlings.
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Shuler, Christopher, Daniel Amato, Veronica Veronica Gibson, Lydia Baker, Ashley Olguin, Henrietta Dulai, Celia Smith e Rosanna Alegado. "Assessment of Terrigenous Nutrient Loading to Coastal Ecosystems along a Human Land-Use Gradient, Tutuila, American Samoa". Hydrology 6, n.º 1 (16 de fevereiro de 2019): 18. http://dx.doi.org/10.3390/hydrology6010018.
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Anthropogenic nutrient loading is well recognized as a stressor to coastal ecosystem health. However, resource managers are often focused on addressing point source or surface water discharge, whereas the impact of submarine groundwater discharge (SGD) as a nutrient vector is often unappreciated. This study examines connections between land use and nutrient loading through comparison of four watersheds and embayments spanning a gradient of human use impact on Tutuila, a high tropical oceanic island in American Samoa. In each study location, coastal radon-222 measurements, dissolved nutrient concentrations, and nitrogen isotope values (δ15N) in water and in situ macroalgal tissue were used to explore SGD and baseflow derived nutrient impacts, and to determine probable nutrient sources. In addition to sampling in situ macroalgae, pre-treated macroalgal specimens were deployed throughout each embayment to uptake ambient nutrients and provide a standardized assessment of differences between locations. Results show SGD-derived nutrient flux was more significant than baseflow nutrient flux in all watersheds, and δ15N values in water and algae suggested wastewater or manure are likely sources of elevated nutrient levels. While nutrient loading correlated well with expected anthropogenic impact, other factors such as differences in hydrogeology, distribution of development, and wastewater infrastructure also likely play a role in the visibility of impacts in each watershed.
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Wibisono, Vicky, e Yudi Kristyawan. "An Efficient Technique for Automation of The NFT (Nutrient Film Technique) Hydroponic System Using Arduino". International Journal of Artificial Intelligence & Robotics (IJAIR) 3, n.º 1 (31 de maio de 2021): 44–49. http://dx.doi.org/10.25139/ijair.v3i1.3209.
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Hydroponic Nutrient Film Technique (NFT) is most widely applied on a home and industrial scale. One of the drawbacks of the NFT hydroponic system is that it is very dependent on electricity for 24 hours to power the water pump. The basic principle of the NFT hydroponic system is to flow nutrients to plant roots with a shallow and circulating nutrient layer so that plants get enough water, nutrients, and oxygen. Therefore, the role of the water pump in the hydroponic NFT system is crucial. This research makes the automation of the NFT hydroponic system more efficient using Arduino. There are two main parts to this automation system: the control of pH levels and nutrient distribution. The pH sensor is used to control the pH level of nutrients, and the ultrasonic sensor is used for nutrient distribution. Efficiency is emphasized more on the distribution of nutrients because it absorbs more electrical energy. The method used is to flow the nutrients in the reservoir to a storage tank that is located higher than the plant using a water pump with a large discharge. Nutrients are transported to each plant using the force of gravity. The nutrient volume is controlled automatically using an ultrasonic sensor in the storage tank. The water pump is only activated by the ultrasonic sensor readings on the storage tank. So that the need for electricity to turn on the water pump is reduced, based on tests carried out on the use of a 220-volt AC / 50 Hz / 125-watt water pump and the use of a 250-liter nutrient storage tank, it can be concluded that the system that has been created can save 70% of electricity consumption.
Teses / dissertações sobre o assunto "Water and nutrient use"
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Wang, Xin. "Linking Hydroperiod with Water Use and Nutrient Accumulation in Wetland Tree Islands". Scholarly Repository, 2011. http://scholarlyrepository.miami.edu/oa_dissertations/531.
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Many large terrestrial ecosystems have patterned landscapes as a result of a positive feedback system between vegetation communities and environmental factors. One example is tree island habitats in the Florida Everglades. Although they only occupy a small portion of the Everglades landscape, tree islands are important features as the focus of nutrient accumulation and wildlife biodiversity in the Everglades ecosystem. The hardwood hammock community on the elevated head of tree island habitats can accumulate high phosphorus concentration in the otherwise P-limited Everglades ecosystem. In this dissertation, I examined two hypotheses derived from the chemohydrodynamic nutrient accumulation model, which suggests that high transpiration of tree island hammock plants is the driving force for nutrient accumulation in tree island soil. According to this model, I hypothesized that tree islands with lower dry season transpiration should have less phosphorus accumulated than the tree islands with higher dry season transpiration. By examining the water use and nutrient status from 18 tree islands in both slough (perennially wet) and prairie (seasonally wet) locations, I was able to compare water availability and nutrient accumulation in slough and prairie tree islands with different marsh hydroperiods. Chapter 1 uses elemental and stable isotope analysis to look at water stress and nutrient concentration in tree island plants. I showed that the prairie tree island plants suffer from drought stress during the dry season, when the marshes in the prairies dry out. Prairie tree islands also have lower soil and plant P concentration than the slough tree islands. Moreover, I showed that foliar N isotope ratio serves as a stable proxy for community level P availability for tree island plants, and prairie tree island plants have less P available than slough tree island plants. In Chapter 2, I showed that the satellite imagery derived normalized difference water index (NDWI) provides a robust indicator of community level canopy water content of these tree islands. NDWI, used as a proxy for water status, was positively related to foliar N isotope ratio, which suggests that water availability is linked to nutrient availability in the tree island hardwood hammock plant communities. These findings are consistent to the chemohydrodynamic nutrient accumulation model. In Chapter 3, I used sap flow sensors on individual trees to provide a real-time measurement of plant transpiration. I showed that tree island plant transpiration is affected by multiple factors including weather fluctuations, marsh water depth regulated by local water management, and canopy structure of different tree islands. Overall, my dissertation establishes a link between tree island plant water use and nutrient accumulation. It could be potentially important for future restoration plan of tree islands and Everglades hydrological management.
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Kempen, Estelle. "Nutrient and water use of tomato (Solanum Lycopersicum) in soilless production systems". Thesis, Stellenbosch : Stellenbosch University, 2015. http://hdl.handle.net/10019.1/97988.
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Thesis (PhD)--Stellenbosch University, 2015.ENGLISH ABSTRACT: Soilless production of crops relies on the addition of high concentrations of nutrients with the irrigation water. The drained nutrient solution should be re-used to reduce the risk of pollution and to increase the water- and nutrient use efficiency of the system. Besides the risk of pathogen build-up, one of the main impediments of a wider application of this method is the frequent analysis required to maintain optimum nutrient concentrations and ratios in the rootzone. Yield reductions may be caused by an unbalanced nutrient solution. Alternatively the addition level of nutrients can be calculated through the use of nutrient uptake models that simulate the change in the re-circulated nutrient solution. To simulate crop water and nutrient demand necessary for model based regulation it was necessary to quantify the key factors affecting nutrient uptake by plants. The nutrient solution concentration and ratios between the macro-nutrients affected the uptake of water and nutrients. The total nutrient uptake per root dry weight increased and more specifically the nitrate (NO3 -), phosphate (H2PO4 -), potassium (K+) and sulphate (SO4 2-) uptake increased with an increase in nutrient solution electrical conductivity (EC) from 0.8 to 4.0 mS cm-1 while water uptake decreased. Except for Ca2+ uptake there was no correlation between nutrient and water uptake. Nutrient uptake can thus not be calculated based on water uptake. Instead a mechanistic high-affinity Michaelis-Menten based model can be used to estimate macro-nutrient uptake (Un, mg m-2 hr-1). Water and nutrient uptake was also affected by the solar radiation levels. Since nutrient uptake is related to the growth rate, solar radiation levels can be expected to influence nutrient uptake. The uptake of all ions increased with an increase in the solar radiation levels and for NO3 -, K+ and H2PO4 - the uptake rate was higher at higher nutrient solution concentrations. The Michaelis-Menten based model was adjusted to incorporate the effect of solar radiation levels on nutrient uptake. Water uptake (Wu, L m-2 day-1) was simulated as a function of crop transpiration and crop leaf area using a linear regression model, but since leaf area development was affected by solar radiation levels this was additionally incorporated into the estimation of the leaf area index (LAI). The composition of the nutrient solution also affected the biomass allocation of the crop which can again affect nutrient use as well as the fruit yield. There was also a direct effect of nutrient solution composition on fruit yield and quality with higher EC’s resulting in smaller fruit but an increase in fruit dry matter %, total soluble solids (TSS), titratable acidity (TA) and lycopene content. The results in this thesis make a valuable contribution to our understanding of the effect of nutrient availability (concentration and ratios) and nutrient requirement for growth (solar radiation levels) on nutrient uptake. Incorporating these into nutrient uptake models resulted in the development of a handy tool to simulate changes in composition of re-circulating nutrient solutions ultimately resulting in an improvement of the water and nutrient use efficiency of soilless systems.
AFRIKAANSE OPSOMMING: Die grondlose verbouing van gewasse is afhanklik van toediening van voedingselemente teen hoë peile in die besproeiingswater. Die voedingsoplossing wat dreineer moet hergebruik word om die risiko van besoedeling te verminder en ook om die water en nutriënt verbruik doeltreffendheid van die sisteem te verbeter. ʼn Ongebalanseerde voedingsoplossing kan ʼn verlaging in opbrengste veroorsaak. Benewens die risiko van patogene wat opbou, is die gereelde analises nodig word vir die handhawing van optimale nutriënt konsentrasies en verhouding tussen elemente in die wortelsone een van die hoof faktore wat ʼn meer algemene gebruik van die metode verhoed. Alternatiewelik kan die nutriënt toedieningspeile bereken word deur voedingstof opname modelle en simulasie van die verandering in water en nutriente wat dreineer. Om ʼn model gebaseerde reguleringsmetode daar te stel was dit nodig om die belangrikste faktore wat nutriënt opname beïnvloed te kwantifiseer. Beide die konsentrasie van die voedingsoplossing en die verhouding tussen elemente het ‘n effek gehad op die opname van water en nutriënte. Die totale nutriënt opname per wortel droë massa het toegeneem. Terwyl water opname afgeneem het met ‘n toename in die elektriese geleding (EG) van die voedingsoplossing vanaf 0.8 tot 4.0 mS cm-1 het die nitraat (NO3 -), fosfaat (H2PO4 -), kalium (K+) en sulfaat (SO4 2-) opname verhoog. Behalwe vir Ca2+ opname was daar geen korrelasie tussen water en nutriënt opname nie. Nutriënt opname kan dus nie bepaal word gebaseer op wateropname nie. Alternatiewelik is die gebruik van ʼn meganistiese hoë-affiniteit Michaelis-Menten-gebaseerde model voorgestel om die opname van makro-nutriente (Un, mg m-2 hr-1) te bepaal. Water- en voedingstofopname is beinvloed deur die ligintensiteit vlakke. Voedingsopname word bepaal deur die groei van die plant, daarom is dit verwag dat ligintensiteit vlakke die opname van voedingstowwe sal beïnvloed. Die opname van al die ione het toegeneem met 'n toename in die ligintensiteit vlakke en die tempo van NO3 -, K+ en H2PO4 - opname was hoër by 'n hoër voedingsoplossing konsentrasie. Die Michaelis-Menten gebaseerde model is aangepas om die effek van ligintensiteit vlakke op nutriënt opname te inkorporeer. Opname van water (Wu, L m-2 dag-1) is gesimuleer as 'n funksie van transpirasie en blaaroppervlakte met behulp van 'n lineêre regressiemodel en aangesien die blaaroppervlak ontwikkeling ook deur ligintensiteit vlakke beïnvloed word, is dit opgeneem in die skatting van die blaaroppervlakte-indeks (LAI). Die samestelling van die voedingsoplossing het die biomassa verspreiding beïnvloed. Dit kan nutriënt gebruik en vrug opbrengs beïnvloed. Die voedingsoplossing samestelling het vrug opbrengs en - kwaliteit beinvloed met kleiner vrugte, maar 'n toename in droëmateriaal %, totale oplosbare vastestowwe (TOVS), titreerbare suur (TA) en likopeen inhoud by ʼn hoër EG. Die resultate in hierdie tesis lewer 'n waardevolle bydrae tot ons begrip van die effek van nutriënt beskikbaarheid (konsentrasie en verhoudings) en voedingstof behoefte vir groei (ligintensiteit vlakke) op voedingsopname. Deur die inligting te inkorporeer in voedingsopname modelle het gelei tot die ontwikkeling van 'n handige instrument om die veranderinge in die samestelling van hersirkulerende voedingsoplossings te simuleer. Dit lei gevolglik tot die verbetering van die water en voedingstof gebruik doeltreffendheid van grondlose stelsels.
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Kerr, Barry Douglas. "Multiple Regression Equations to Estimate Mean Nutrient Concentrations in Streams of North Central Texas from Landsat Derived Land Use". Thesis, University of North Texas, 1994. https://digital.library.unt.edu/ark:/67531/metadc278778/.
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Nutrients are of critical concern in water quality assessment. The development of empirical models to estimate mean nutrient concentrations, based on satellite derived land use, could aid water resource managers. Models using land use acreages outperformed those using percentages, and discrete urban land uses were superior to lumped urban. Regressions of the combinations of two, three and four of the eight possible land use variables were investigated. Sensitivity analyses, with one stream deleted each series, identified robust combinations of variables at each level. Although uncertainty exists regarding the final regression coefficients, five of the six actual measured nitrate and total phosphorus mean concentrations were within the 95 percent confidence limits.
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Mir, Rigau Xavier. "Land Use Impact Assessment on the Nutrient Transport in the lake Mälaren". Thesis, KTH, Mark- och vattenteknik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-170450.
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Stockholm and its surroundings are facing strong urban changes and it is forecasted that the increase of population will be the principal driver for the urban regions surrounding the lake Mälaren in the next decades. A thorough regional and urban planning is needed in order to build a sustainable society and protect the environment. In this sense Coupled Human and Natural Systems (CHANS) are useful tools for the creation of future scenarios of how urbanization and landuse changes will impact the ecosystems and the water resources. This master thesis is focused on how population growth and landuse changes impact both the surface water discharges and the nutrient transport in the Norrström Drainage Basin. In this regard the different comprehensive plans of 26 municipalities in the Stockholm-Mälardalen region were studied in order to create a landuse evolution model until 2040. The impacts of the changes of urbanization on the surface waters and the nutrient transport were obtained using the PCRaster environmental modelling tool following the guidelines of the PolFlow model. The results show an increase of the built-up urban areas of a 25% by 2040. Regarding the increase of flow in the surface waters, the results show a very small increase in the flow, due to the large scale of the study area. Finally the results for the nutrient transport show an increase of the nutrient loads at the outlet of the lake Mälaren of 20% in the case of nitrogen and 15% for phosphorus.Stockholm regionen står inför kraftiga urbana förändringar och det förutses att befolkningsökningen kommer att bli den främsta drivkraften för storstadsregionerna kring Mälaren under de kommande årtiondena. En grundlig regional- och stadsplanering behövs för att bygga ett hållbart samhälle och skydda miljön. I detta sammanhang är Coupled Human and Natural Systems (CHANS) användbara verktyg för att skapa framtidsscenarier för hur urbanisering och markanvändningar kommer att påverka ekosystem och vattenresurser. CHANS verktyg möjliggör analys av komplexa mönster och processer som inte framgår tydligt vid separata sociala och naturvetenskapliga studier. Inom CHANS ramverk fokuserar detta examensarbete på hur befolkningstillväxt och markanvändning och de ändringear de medför påverkar ytvattenutsläpp samt näringstransport i Norrström avrinningsområden. I detta avseende studerades olika översiktsplaner av 26 kommuner i Stockholm-Mälardalen regionen för att bygga en markanvändning evolutionmodell fram till 2040. Det studerade scenariot utvärderade konsekvenser av förändringarna i urbaniseringen som beskrivs i de omfattande översiktplanerna på ytvatten och näringsämne transport. Verktyget som användes för att utföra detta examensarbete var PCRaster. Det är ett miljömodelleringsverktyg som tillåter behandling av stora distribuerade data och kan skapa spatiotemporala miljömodeller. I detta avseende fördelades modellen i tre delar. Först erhölls den temporala markanvändningsevolutionen efter uppgifter från kommunala översiktplaner. Därefter beräknades ytvattenutsläppen med CN-metoden. Slutligen byggdes den näringstransportmodellen med hjälp av riktlinjerna från PolFlow modellen och näringsbelastningen från HELCOM och TRK-projektet. Resultaten visar en ökning av de bebyggda stadsområdena från 3,3 % bebyggda under år 2005 till 4,2 % år 2040 för hela Norrström avrinningsområde, som innebär en ökning med 25 % av de bebyggda områdena. Beträffande flödet i ytvattnet visar resultaten en jätteliten ökning av flödet på grund av att det studerade området har en stor skala. Slutligen visar resultaten för näringsämnenstransport en ökning av näringsbelastningen vid utloppet av sjön Mälaren med 20 % kväve och 15 % fosfor.
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Becnel, Audrey R. "Land Use and Water Quality Correlations in Miami-Dade, Florida". FIU Digital Commons, 2014. http://digitalcommons.fiu.edu/etd/1549.
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South Florida continues to become increasingly developed and urbanized. My exploratory study examines connections between land use and water quality. The main objectives of the project were to develop an understanding of how land use has affected water quality in Miami-Dade canals, and an economic optimization model to estimate the costs of best management practices necessary to improve water quality. Results indicate Miami-Dade County land use and water quality are correlated. Through statistical factor and cluster analysis, it is apparent that agricultural areas are associated with higher concentrations of nitrogen, while urban areas commonly have higher levels of phosphorous than agricultural areas.
The economic optimization model shows that urban areas can improve water quality by lowering fertilizer inputs. Agricultural areas can also implement methods to improve water quality although it may be more expensive than urban areas. It is important to keep solutions in mind when looking towards future water quality improvements in South Florida.
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Edwards, Richard Reginald. "The potential for the use of willow (Salix spp.) in buffer zones for reducing nitrate and atrazine pollution". Thesis, University of Bristol, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.322361.
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Taylor, Richard Peter. "The use of treated brewery effluent as a water and nutrient source in crop irrigation". Thesis, Rhodes University, 2016. http://hdl.handle.net/10962/d1021265.
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Brewery effluent (BE) needs to be treated before it can be released into the environment, reused or used in down-stream activities. Current technologies used to address this concern at the experimental wastewater treatment plant at Ibahyi Brewery (SAB Ltd) include anaerobic digestion (AD), primary facultative ponds (PFP), high rate algal ponds (HRAP) and constructed wetlands (CW). The aim of this work was to determine if BE treated in these systems might be suitable for crop irrigation. A test crop, cabbage (Brassica oleracea cv. Star 3301), grew best on post-AD and post-PFP BE compared to those irrigated with post-HRAP or post-CW effluent. However, the yield was 13% lower than cabbage plants irrigated with a commercial nutrient solution and fresh water. The relatively high conductivity (3019.05 ± 48.72 μs/cm2) of BE may be the main factor reducing the cabbage yields. Post-HRAP and post-CW BE were the least suitable for irrigated crop production due to the higher conductivity and lower nutrient content of these treated effluents. After three months, soils irrigated with post-AD and post-PFP BE had a significantly higher sodium content and sodium adsorption ratio (3919 ± 94.77 mg/kg & 8.18 ± 0.17) than soil irrigated with a commercial nutrient solution (920.58 ± 27.46 mg/kg & 2.20 ± 0.05; p<0.05). However, this was not accompanied by a deterioration in the soil’s hydro-physical properties, nor a change in the metabolic community structure of the soil (p>0.05). After prolonged irrigation with treated BE, sodium is likely to build up in the soil and this can be expected to be accompanied by a deterioration in the soil physical structure. However, crops species such as millet (Echinochloa esculenta), lucerne (Medicago sativa) and saltbush (Atriplex nummularia) reduced the build-up of sodium in the soil. The results suggest that sodium was mainly removed from the soil through plant-assisted leaching. Of the crops grown, lucerne showed the most promise because it improved the soil physical properties, is able to grow well in alkaline environments, is a popular fodder crop and can be harvested multiple times from a single stand. Brewery effluent is more suitable for soil production systems than hydroponic production systems because the soil was able to act as a buffer against the high pH of post-AD BE, whereas in a hydroponics systems the high pH reduced the availability of key minerals to plants. In conclusion brewery effluent contains sufficient plants nutrients to support the growth of cabbages, saltbush, lucerne and millet. However the sodium content of BE is a concern as it accumulates in the soil, and in the long-term it may lead to soil degradation. It is suggested that the brewery change the pH neutralising treatment of BE from sodium hydroxide to potassium hydroxide, or dolomitic lime (calcium and magnesium carbonate) because this would reduce the introduction of sodium into the system, and would increase the suitability of BE for crop production, given potassium and calcium are plant nutrients. The benefits of developing this nutrient and water resource could contribute to cost-reductions at the brewery, more efficient water, nutrient and energy management, create job opportunities with the potential of improving food security in the local community.
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Hoskins, Tyler Courtney. "Water and nutrient transport dynamics during the irrigation of containerized nursery crops". Thesis, Virginia Tech, 2014. http://hdl.handle.net/10919/48165.
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Increased water- and fertilizer-use-efficiency in containerized crop production, via reduced water loss, enhances crop-available nutrients while reducing non-point source agrichemical contributions in accordance with regulatory standards. Previous studies detailed nutrient leaching patterns throughout crop production seasons, leaving little known about water and dissolved nutrient (solute) movement through soilless substrates during irrigation. The following experiments evaluated fundamental water and solute transport principles through pine-bark based substrates. 1) Ilex crenata Thunb. 'Bennett's Compactum' were grown in 2.7 L containers. Tensiometers detected wetting front (WF) movement throughout the substrate during irrigation. 2) Tracer solution (containing NO3-, PO43- and K+) and deionized water (DI) were applied to substrate-filled columns to characterize tracer breakthrough under saturated and unsaturated conditions. 3) Controlled-release fertilizer (CRF) was topdressed (surface-applied), incorporated (throughout substrate), dibbled (center of substrate) or not applied to fallow substrate, irrigated with DI and leachate analyzed to determine nutrient concentrations throughout irrigation. Tensiometers revealed that seasonal root growth affected substrate pre-irrigation moisture distribution. Wetting fronts channeled through the substrate before becoming thoroughly wetted. Tracer breakthrough occurred with less effluent volume under unsaturated conditions. Breakthrough of NO3- and PO43- was relatively conservative, though 37% of K+ was retained by the substrate. Leachate concentrations for topdressed and incorporated CRF peaked early (first 50mL effluent) before diminishing with continued leaching. Leachate concentrations for dibbled CRF initially increased (first 150mL leachate), plateaued and then diminished. These results show the relative rapidity which water and solutes move through pine-bark during irrigation and demonstrate methods for future research on within-irrigation solute transport.Master of Science
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Mack, Rachel E. "Best Management Practice Use and Efficacy for the Virginia Nursery and Greenhouse Industry". Thesis, Virginia Tech, 2017. http://hdl.handle.net/10919/84159.
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Best management practices (BMPs) are used in the nursery and greenhouse industry to increase production efficiency, and also serve to help meet clean water limitations on contaminants entering waters such as the Chesapeake Bay Watershed. Research is lacking on which BMPs are most widely used or most efficacious for Virginia nursery and greenhouse growers. Objectives of this work were to determine BMP use, barriers to adoption, and scientific efficacy.
We conducted a survey of Virginia growers to find the 1) most widely used BMPs, 2) reasons behind BMP use, and 3) any barriers to BMP adoption. Sixty growers (17%) responded to the survey. The most widely used BMPs included irrigation scheduling, integrated pest management, optimized irrigation efficiency, plant need based watering, grouping plants by water needs, on-site water capture and collection, and use of controlled-release fertilizers (CRFs). Cost was a barrier to BMP adoption, and environmental concern was a commonly reported reason for BMP use. We documented the science supporting selected water-related BMPs (grass buffer strips, CRFs, and irrigation optimization BMPs). Providing the science supporting BMP use gives growers confidence in implementing BMPs to limit water contamination, and prevent waste.Master of Science
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Spooner, Daniel Ron, e n/a. "Nutrient, organic carbon and suspended solid loadings in two ICOLLs, NSW Australia : biogeochemical responses". University of Canberra. Resource, Environmental & Heritage Sciences, 2005. http://erl.canberra.edu.au./public/adt-AUC20070129.130745.
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Intermittently Closed and Open Lake Lagoons (ICOLLs) are very common along the
southern NSW coastline. Expanding urban populations are expanding and these systems are
under increasing pressure from anthropogenic activities that change landscape processes and
significantly alter the amounts of organic and inorganic constituents entering their waters.
Once efficient cycling of nutrients in ICOLLs is overcome, the symptoms of eutrophication
establish and the entire ecosystem suffers. These systems have great ecological, social, and
economic values that require insightful, well balanced, and educated management to
promote sustainable use of these often-sensitive areas.
Corunna and Nangudga Lake are ICOLLs in the Eurobodalla Shire on the south
coast of NSW. These two ICOLLs receive discharges from catchments covered by native
vegetation and grassland. The primary objective of this research component was to quantify
catchment exports of total nitrogen (TN), total phosphorus (TP), suspended solids (SS),
particulate organic matter (POM) and dissolved organic carbon (DOC) from three small
coastal sub catchments that deliver constituents into Corunna and Nangudga Lakes. As part
of this investigation the fates of catchment loads in the ICOLLs were established focusing
on the lakes water column response to catchment loads and the biogeochemical cycling of
nitrogen and phosphorus in sediments.
Livros sobre o assunto "Water and nutrient use"
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Willigen, Peter de. Roots, plant production and nutrient use efficiency. Wageningen: Landbouwuniversiteit te Wageningen, 1987.
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Rengel, Zed, ed. Improving Water and Nutrient-Use Efficiency in Food Production Systems. Hoboken, NJ, USA: John Wiley & Sons, Inc, 2013. http://dx.doi.org/10.1002/9781118517994.
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Edwards, Robert E. Nutrient trends and land use changes in selected watersheds in the Lower Susquehanna River Basin. Harrisburg, Pa: Susquehanna River Basin Commission, 1987.
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Zimmerman, Marc James. Assessment of data for use in the development of nutrient criteria for Massachusetts rivers and streams. Reston, Va: U.S. Geological Survey, 2007.
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Protection, Center for Watershed, e Chesapeake Research Consortium, eds. Nutrient loading from conventional and innovative site development: Final report. Edgewater, MD: The Consortium, 1998.
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Corangamite Catchment Management Authority (Vic.), ed. Corangamite Region nutrient management plan: A framework to reduce the incidence of blue-green algal blooms in regional waters. Colac: Corangamite Catchment Management Authority, 2000.
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M, Wheeler R., e United States. National Aeronautics and Space Administration., eds. A data base of nutrient use, water use, CO₂ exchange, and ethylene production by soybeans in a controlled environment. [Washington, D.C: National Aeronautics and Space Administration, 1998.
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L, Heathwaite A., International Association of Hydrological Sciences. e International Union of Geodesy and Geophysics. General Assembly, eds. Impact of land-use change on nutrient loads from diffuse sources: Proceedings of an international symposium held during IUGG 99, the XXII General Assembly of the International Union of Geodesy and Geophysics, at Birmingham, UK 18-30 July 1999. Wallingford: IAHS, 1999.
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L, Heathwaite A., International Association of Hydrological Sciences. e International Union of Geodesy and Geophysics. General Assembly, eds. Impact of land-use change on nutrient loads from diffuse sources: Proceedings of an international symposium held during IUGG 99, the XXII General Assembly of the International Union of Geodesy and Geophysics, at Birmingham, UK 18-30 July 1999. Wallingford: IAHS, 1999.
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Paschal, James E. Relation of sediment and nutrient loads to watershed characteristics and land use in the Otisco Lake Basin, Onondaga County, New York. Ithaca, N.Y: U.S. Dept. of the Interior, Geological Survey, 1987.
Encontre o texto completo da fonteCapítulos de livros sobre o assunto "Water and nutrient use"
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Hendricks, Sterling B. "Nutrient Transfer and Plant Absorption Mechanisms". In Plant Environment and Efficient Water Use, 150–76. Madison, WI, USA: American Society of Agronomy, Soil Science Society of America, 2015. http://dx.doi.org/10.2134/1966.plantenvironment.c8.
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Mitra, Sisir. "Plant nutrition and irrigation." In Guava: botany, production and uses, 148–71. Wallingford: CABI, 2021. http://dx.doi.org/10.1079/9781789247022.0007.
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Abstract This chapter focuses on plant nutrition and irrigation in guava production. Information is given on soil, salinity, nutrient uptake, role of nutrients, fertilizer rate and time of application, foliar application, integrated nutrient management, tissue analysis, organic production, water management, and fertigation.
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Grote, Ulrike, Eric T. Craswell e Paul L. G. Vlek. "Nutrient and Virtual Water Flows in Traded Agricultural Commodities". In Land Use and Soil Resources, 121–43. Dordrecht: Springer Netherlands, 2008. http://dx.doi.org/10.1007/978-1-4020-6778-5_7.
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Kirkegaard, John A., e Michael J. Robertson. "Agronomic Principles of Water- and Nutrient-Use Efficiency". In Improving Water and Nutrient-Use Efficiency in Food Production Systems, 211–33. Hoboken, NJ, USA: John Wiley & Sons, Inc, 2013. http://dx.doi.org/10.1002/9781118517994.ch13.
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Reddy, P. Parvatha. "Fertigation: Enhancing Irrigation Water and Nutrient Use Efficiency". In Hi-Tech Farming for Enhancing Horticulture Productivity, 163–88. London: CRC Press, 2023. http://dx.doi.org/10.1201/9781032690568-7.
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Kędziora, Andrzej, e Zbigniew W. Kundzewicz. "Translating Water into Food:". In Improving Water and Nutrient-Use Efficiency in Food Production Systems, 33–56. Hoboken, NJ, USA: John Wiley & Sons, Inc, 2013. http://dx.doi.org/10.1002/9781118517994.ch3.
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Blair, Matthew W. "Breeding Approaches to Increasing Nutrient-Use Efficiency". In Improving Water and Nutrient-Use Efficiency in Food Production Systems, 161–75. Hoboken, NJ, USA: John Wiley & Sons, Inc, 2013. http://dx.doi.org/10.1002/9781118517994.ch10.
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Sarkar, Binoy, e Ravi Naidu. "Nutrient and Water Use Efficiency in Soil: The Influence of Geological Mineral Amendments". In Nutrient Use Efficiency: from Basics to Advances, 29–44. New Delhi: Springer India, 2014. http://dx.doi.org/10.1007/978-81-322-2169-2_3.
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Wegehenkel, Martin. "Water Resources and Global Change". In Improving Water and Nutrient-Use Efficiency in Food Production Systems, 21–31. Hoboken, NJ, USA: John Wiley & Sons, Inc, 2013. http://dx.doi.org/10.1002/9781118517994.ch2.
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Merchuk, Lianne, e Yehoshua Saranga. "Breeding Approaches to Increasing Water-Use Efficiency". In Improving Water and Nutrient-Use Efficiency in Food Production Systems, 145–60. Hoboken, NJ, USA: John Wiley & Sons, Inc, 2013. http://dx.doi.org/10.1002/9781118517994.ch9.
Texto completo da fonteTrabalhos de conferências sobre o assunto "Water and nutrient use"
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Zhang, Ning, e Weihao Wang. "Investigation of Water pH in Calcasieu Lake Area Using Regional Scale Hydrodynamic Models". In ASME 2017 Fluids Engineering Division Summer Meeting. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/fedsm2017-69208.
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In Southwest Louisiana, the Calcasieu Lake and surrounding water systems are the major fresh water sources to the nearby coastal wetlands and agricultural areas. There are two national wide life refuges located in both east and west sides of Calcasieu Lake. Both refuges are covered by coastal wetlands. The health of the wetland vegetation is essential to the wetland losses in the area. One of the major problems related to the health of marshes is the nutrient deficiency. In addition, the surface water system is a possible source for agriculture use that requires sufficient nutrient components in water. Understanding the transport and distribution of various nutrients in the coastal water system is very important to the above-mentioned issues. In this study, a regional scale hydrodynamic model was utilized to simulate the hydrodynamics, salinity transport and sediment transport in this major water system in Southwest Louisiana. The pH distribution in water is a good indication of many nutrient components, such as phosphorous, and is essential to understand the nutrient distributions in the target area. A pH calculation procedure was implemented in the model to determine pH values based on the salinity and other water properties. The model results can be used to indicate the dynamic change of nutrient distributions and the areas of nutrient deficiency.
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Howard, Lucas M., e Dina L. Lopez. "Nutrient and Sulfate Variations along the Maumee River, Ohio, USA". In World Environmental and Water Resources Congress 2019. Reston, VA: American Society of Civil Engineers, 2019. http://dx.doi.org/10.1061/9780784482339.033.
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Ozkan, Altan, Kerry Kinney, Lynn Katz e Halil Berberoglu. "Novel Algae Biofilm Photobioreactor for Reduced Energy and Water Usage". In ASME 2010 International Mechanical Engineering Congress and Exposition. ASMEDC, 2010. http://dx.doi.org/10.1115/imece2010-39621.
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This paper reports the design and performance of a novel photobioreactor that decreases the water requirements of algae cultivation and energy requirements of harvesting and downstream processing for biofuel production compared to conventional technologies. The photobioreactor cultivates algae as a biofilm, immobilized on carbonated concrete surface. In this study the well known lipid producer Botryococcus braunii was used. The nutrient solution was flown over the surface to enhance the mass transfer of nutrients in and metabolites out of the algae biofilm. The prototype featured a footprint area of 0.275 m2 and has been operated for 35 days. The algae concentration in the photobioreactor reached 30.73 kg/m3 with a maximum total lipid content of 12.3% by dry weight. The water requirement for cultivation was reduced up to by about 41.58 times and energy required for nutrient delivery was estimated to be reduced by about 230 times with respect to raceway ponds.
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Dovel, E. L., e A. L. Welker. "The Use of Temperature as a Proxy for Nutrient Reduction: a Low-Cost Inspection Tool for Stormwater Control Measures". In World Environmental and Water Resources Congress 2013. Reston, VA: American Society of Civil Engineers, 2013. http://dx.doi.org/10.1061/9780784412947.299.
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Asryan, V. R. "APPLICATION OF BIOTECHNOLOGIES IN THE PRODUCTION OF BRADIC CROPS". In INNOVATIVE TECHNOLOGIES IN SCIENCE AND EDUCATION. ООО «ДГТУ-Принт» Адрес полиграфического предприятия: 344003, г. Ростов-на-Дону, пл. Гагарина,1., 2023. http://dx.doi.org/10.23947/itse.2023.36-38.
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This article discusses the use of biotechnology in the production of fermentation crops. Describes how genetic engineering can be used to change the content of vitamins, minerals and other beneficial substances in plants, which is especially useful in conditions of nutrient deficiency. The possibility of creating plants that use water and nutrients more efficiently, which contributes to the conservation of resources, is also being considered. In addition, the possibility of creating plants with improved preservation and better transportability is discussed, which helps to reduce product losses and ensure the availability of fermentation crops for consumers.
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Tevi, Giuliano. "EFFECTS OF NUTRIENT POLLUTION ON GROUND WATER USED FOR DRINKING PURPOSES". In 14th SGEM GeoConference on WATER RESOURCES. FOREST, MARINE AND OCEAN ECOSYSTEMS. Stef92 Technology, 2014. http://dx.doi.org/10.5593/sgem2014/b31/s12.029.
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Waters, Geoffrey, Youbin Zheng, Danuta Gidzinski e Michael Dixon. "Carbon Gain, Water Use and Nutrient Uptake Dynamics of Beet (Beta vulgaris) Grown in Controlled Environments". In International Conference On Environmental Systems. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 2004. http://dx.doi.org/10.4271/2004-01-2435.
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BRIUKHANOV, Aleksandr, Sergey KONDRATYEV, Veronica TARBAEVA, Ekaterina VOROBYEVA e Natalia OBLOMKOVA. "CONTRIBUTION OF AGRICULTURAL SOURCES TO NUTRIENT LOAD GENERATED ON THE RUSSIAN PART OF THE BALTIC SEA CATCHMENT AREA". In RURAL DEVELOPMENT. Aleksandras Stulginskis University, 2018. http://dx.doi.org/10.15544/rd.2017.058.
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Agricultural production is one of the main sources of nitrogen and phosphorous inputs to the water bodies. Quantifying nutrient input from agriculture is needed both to develop effective environmental measures and to justify the technologies to be applied with due account for local natural and climatic conditions. Several related national studies have been conducted since 2015. Institute for Engineering and Environmental Problems in Agricultural Production (IEEP) methodology was used for this purpose. It determines the nitrogen and phosphorus content in the arable layer, including N and P amounts applied with mineral and organic fertilisers. Such factors as soil type and texture, the distance to the water bodies and the land use structure are used to estimate the nutrient input to the water bodies. In addition, the consistency of manure handling technologies with Best Available Techniques (BAT) principles is taken into account through introduction of relevant coefficients. Calculation results according to IEEP methodology were used in the follow-up general assessment of the nutrient load on the water bodies from different sources with the use of Institute of Limnology Load Model. Satisfactory correspondence between the assessment results and the values calculated using the monitoring data confirmed the adequacy of the above assessment procedure. Following its outcomes, the nutrient reduction potential of agricultural sources is approximately 10–20 %.
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Liu, Songyuan, Chao-yu Sie, Fatee Malekahmadi, Bo Lu, Yifan Li, Cara Fan, Xinyue Zhang, Owen Serediak, Jelayne Fortin e Ali Abedini. "Bioremediation Study on Formation Damage Caused by Hydraulic Fracturing: A Microfluidic Approach". In SPE Annual Technical Conference and Exhibition. SPE, 2022. http://dx.doi.org/10.2118/210089-ms.
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Abstract Hydraulic fracturing has been applied to unconventional reservoirs with low permeability to achieve higher productivity and economic potential. However, polyacrylamide-based friction reducer and guar gum, two of the most common components in fracturing fluid could cause formation damage by penetrating into the matrix and blocking the flow path. To regain the conductivity of the damaged area, a bioremediation method was developed and validated by a microfluidic approach. Modified nutrients were used to stimulate the indigenous bacteria that could consume or break the polymer residues. Indigenous bacteria were extracted from oil field produced water collected with customized anaerobic sampling kits which have been sterilized. Feasibility studies were conducted to investigate the indigenous bacteria activity with and without nutrient supply. Fracturing fluid, field water, and a modified nutrient recipe which contained 300 ppm of inorganic salts were loaded into anaerobic sample vials in a 140°F - 150°F incubator. Microfluidic tests were performed in 150°F oven with microfluidic chips designed and fabricated based on the topology of matrix networks. Fracturing fluids were injected into a chip saturated with field water to simulate formation damage. Remediation fluid consisting produced water, injection water and nutrient was injected into the chip. After two weeks soaking, 2% KCl brine was then injected into the chip at 200 nl/min until a stable pressure drop was achieved. Microscopic pictures were taken before and after soaking to demonstrate the polymer damage and the remediation of microfluidic chips. The indigenous bacteria were successfully stimulated with and without the existence of the friction reducer based on the results of feasibility tests. Microfluidic tests showed there is a significant difference in precipitations between the case with and without nutrient supply, which indicates that the bioremediation method could regain conductivity of the damaged formation. This work is novel research on bioremediation application in unconventional reservoirs with only indigenous bacteria involved. The customized sampling technology and laboratory approach could prevent contamination of other microbes and oxygen, which could improve the quality of the research. Microfluidic chip is a great simulation of porous media and a proof of concept between scientific hypothesis and field application which requires small sample size and provides good reproducibility. In field applications, only an extremely low amount of nutrient is required in this process which provide great economic potential. Additionally, the injected nutrients will be fully consumed by the bacteria which makes this technology is an Environmental, Social and Governance (ESG) approach in energy industry.
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Chang, Ni-Bin, Martin Wanielista e Andrew O'Reilly. "Use of Alternative Sorption Media for Removing Nutrients Associated with Stormwater BMPs". In World Environmental and Water Resources Congress 2007. Reston, VA: American Society of Civil Engineers, 2007. http://dx.doi.org/10.1061/40927(243)18.
Texto completo da fonteRelatórios de organizações sobre o assunto "Water and nutrient use"
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Theiling, Charles. A review of algal phytoremediation potential to sequester nutrients from eutrophic surface water. Engineer Research and Development Center (U.S.), outubro de 2023. http://dx.doi.org/10.21079/11681/47720.
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Harmful algal blooms (HABs) and coastal hypoxic zones are evidence of cultural nutrient enrichment affecting public health and water supplies, aquatic ecosystem health, and economic well-being in the United States. Recognition of the far-reaching impacts of Midwest agriculture has led to establishing nutrient reduction objectives for surface waters feeding the Gulf of Mexico, Lake Erie, and many smaller water bodies. Municipal nutrient enrichment impacts have been addressed by increasing levels of sewage treatment and waste management through the Clean Water Act era, but HABs rebounded in the 1990s because of non-point source nutrient enrichment. HAB control and treatment includes watershed and waterbody treatments to reduce loading and address outbreaks. Systems to remove nutrients from impaired waters are expensive to build and operate. This review of algal production systems summarizes emerging algal water treatment technologies and considers their potential to effectively sequester nutrients and atmospheric carbon from hundreds of eutrophic reservoirs and DoD wastewater treatment facilities while producing useful biomass feedstock using solar energy. Algal water treatment systems including open ponds, photobioreactors, and algal turf scrubbers® can be used to grow biomass for biofuel, wastewater treatment, and commercial products. This review recommends continuing research on surface water nutrient reduction potential with algal turf scrubber productivity pilot studies, preliminary site design, and biomass utilization investigations.
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Jones, Scott B., Shmuel P. Friedman e Gregory Communar. Novel streaming potential and thermal sensor techniques for monitoring water and nutrient fluxes in the vadose zone. United States Department of Agriculture, janeiro de 2011. http://dx.doi.org/10.32747/2011.7597910.bard.
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The “Novel streaming potential (SP) and thermal sensor techniques for monitoring water and nutrient fluxes in the vadose zone” project ended Oct. 30, 2015, after an extension to complete travel and intellectual exchange of ideas and sensors. A significant component of this project was the development and testing of the Penta-needle Heat Pulse Probe (PHPP) in addition to testing of the streaming potential concept, both aimed at soil water flux determination. The PHPP was successfully completed and shown to provide soil water flux estimates down to 1 cm day⁻¹ with altered heat input and timing as well as use of larger heater needles. The PHPP was developed by Scott B. Jones at Utah State University with a plan to share sensors with Shmulik P. Friedman, the ARO collaborator. Delays in completion of the PHPP resulted in limited testing at USU and a late delivery of sensors (Sept. 2015) to Dr. Friedman. Two key aspects of the subsurface water flux sensor development that delayed the availability of the PHPP sensors were the addition of integrated electrical conductivity measurements (available in February 2015) and resolution of bugs in the microcontroller firmware (problems resolved in April 2015). Furthermore, testing of the streaming potential method with a wide variety of non-polarizable electrodes at both institutions was not successful as a practical measurement tool for water flux due to numerous sources of interference and the M.S. student in Israel terminated his program prematurely for personal reasons. In spite of these challenges, the project funded several undergraduate students building sensors and several master’s students and postdocs participating in theory and sensor development and testing. Four peer-reviewed journal articles have been published or submitted to date and six oral/poster presentations were also delivered by various authors associated with this project. We intend to continue testing the "new generation" PHPP probes at both USU and at the ARO resulting in several additional publications coming from this follow-on research. Furthermore, Jones is presently awaiting word on an internal grant application for commercialization of the PHPP at USU.
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Raikow, David, Mark Wasser, Amanda McCutcheon e Anne Farahi. Trends in water quality of Waikolu Stream, Kalaupapa National Historical Park, Moloka?i, Hawaii, 2007?2017. National Park Service, 2024. http://dx.doi.org/10.36967/2302153.
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Water quality was monitored in Waikolu Stream, Kalaupapa National Historical Park, Moloka?i, Hawa?i from 2007-2017. Water was collected for nutrient analyses and a sonde equipped with multiple probes was used to measure water quality parameters. The sampling regime was based on a split-panel of permanently established or ?fixed? sites sampled during each sampling effort, and ?temporary? sites of randomly assigned locations, for each sampling effort. Results included: ? NO-3 + NO-2 regularly exceeded state water quality criteria. ? TP exceeded state water quality criteria once out of three quarters evaluated. ? Other nutrient concentrations were consistent with Hawaiian streams. ? Waters were clear and well oxygenated. ? Conditions were consistent with similar pacific island streams. ? Dissolved nutrient fractions dominated base flow conditions. ? Seasonality was detected for TDN, NO-3 + NO-2, chlorophyll, pH, oxygen, and temperature. ? Several trends were detected; however, the magnitude of change was small and did not warrant concern. ? Temporal patterns did not obviously correspond to climate conditions. ? Parameters varied spatially to a limited extent, with nitrogen decreasing and temperature, specific conductance, and oxygen increasing from headwaters to the mouth. ? Temporary site conditions were highly correlated with fixed sites and did not provide additional insights. Water quality in Waikolu Stream was generally good with the exception of NO-3 + NO-2 which exceeded state standards. However, concentrations of NO-3 + NO-2 were generally consistent with many streams in Hawaii and natural causes of observed concentrations may have included older soils, steep slopes, and high precipitation. Exotic species including ungulates, which are known to occur in Waikolu Valley, could have contributed to elevated N through droppings and soil erosion in the riparian zone. Waikolu Stream TDN, TDP, chlorophyll, pH, turbidity, SpC, and oxygen were consistent with streams in other well-protected NPS watersheds on pacific islands on Maui, Guam, and American Samoa. Due to the watershed?s small size, the stream?s short length, and because variation or unique conditions were not captured by using split-panel, we recommend reducing the sampling effort. For example, our observations indicate that one easily accessible site in the lower reaches of the stream (FKALA03) displays water quality that reflects the entire stream. We also recommend adding nutrient analytes to better characterize biogeochemical cycling in this stream, including TP, TN, NH+4, and PO4. A power analysis is underway to evaluate reduction of sample sites. Such a reduction will result in large cost savings for the PACN water quality monitoring program.
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Dick, Warren, Yona Chen e Maurice Watson. Improving nutrient availability in alkaline coal combustion by-products amended with composted animal manures. United States Department of Agriculture, 2002. http://dx.doi.org/10.32747/2002.7587240.bard.
Texto completo da fonteResumo:
Hypothesis and Objectives: We hypothesized that coal combustion products (CCPs), including those created during scrubbing of sulfur dioxide from flue gases, can be used alone or mixed with composted animal manures as effective growth media for plants. Our specific objectives were, therefore, to (1) measure the chemical, physical and hydraulic properties of source materials and prepared mixes, (2) determine the optimum design mix of CCPs and composted animal manures for growth of plants, (3) evaluate the leachate water quality and plant uptake of selected elements from prepared mixes, (4) quantify the interaction between composted animal manures and B concentrations in the mixes, (5) study the availability of P to plants growing in the mixes, and (6) determine the microbial community and siderophores involved in the solubilization of Fe and its transfer to plants. Background: In recent years a major expansion of electricity production by coal combustion has taken place in Israel, the United States and the rest of the world. As a result, a large amount of CCPs are created that include bottom ash, fly ash, flue gas desulfurization (FGD) gypsum and other combustion products. In Israel 100,000 tons of fly ash (10% of total CCPs) are produced each year and in the US a total of 123 million tons of CCPs are produced each year with 71 million tons of fly ash, 18 million tons of bottom ash and 12 million tons of FGD gypsum. Many new scrubbers are being installed and will come on-line in the next 2 to 10 years and this will greatly expand the amount of FGD gypsum. One of the main substrates used in Israel for growth media is volcanic ash (scoria; tuff). The resemblance of bottom coal ash to tuff led us to the assumption that it is possible to substitute tuff with bottom ash. Similarly, bottom ash and FGD gypsum were considered excellent materials for creating growth mixes for agricultural and nursery production uses. In the experiments conducted, bottom ash was studied in Israel and bottom ash, fly ash and FGD gypsum was studied in the US. Major Achievements: In the US, mixes were tested that combine bottom ash, organic amendments (i.e. composts) and FGD gypsum and the best mixes supported growth of tomato, wheat and marigolds that were equal to or better than two commercial mixes used as a positive control. Plants grown on bottom ash in Israel also performed very well and microelements and radionuclides analyses conducted on plants grown on bottom coal ash proved it is safe to ingest the edible organs of these plants. According to these findings, approval to use bottom coal ash for growing vegetables and fruits was issued by the Israeli Ministry of Health. Implications: Bottom coal ash is a suitable substitute for volcanic ash (scoria; tuff) obtained from the Golan Heights as a growth medium in Israel. Recycling of bottom coal ash is more environmentally sustainable than mining a nonrenewable resource. The use of mixes containing CCPs was shown feasible for growing plants in the United States and is now being evaluated at a commercial nursery where red sunset maple trees are being grown in a pot-in-pot production system. In addition, because of the large amount of FGD gypsum that will become available, its use for production of agronomic crops is being expanded due to success of this study.
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Dick, Warren, Yona Chen e Maurice Watson. Improving nutrient availability in alkaline coal combustion by-products amended with composted animal manures. United States Department of Agriculture, dezembro de 2006. http://dx.doi.org/10.32747/2006.7695883.bard.
Texto completo da fonteResumo:
Hypothesis and Objectives: We hypothesized that coal combustion products (CCPs), including those created during scrubbing of sulfur dioxide from flue gases, can be used alone or mixed with composted animal manures as effective growth media for plants. Our specific objectives were, therefore, to (1) measure the chemical, physical and hydraulic properties of source materials and prepared mixes, (2) determine the optimum design mix of CCPs and composted animal manures for growth of plants, (3) evaluate the leachate water quality and plant uptake of selected elements from prepared mixes, (4) quantify the interaction between composted animal manures and B concentrations in the mixes, (5) study the availability of P to plants growing in the mixes, and (6) determine the microbial community and siderophores involved in the solubilization of Fe and its transfer to plants. Background: In recent years a major expansion of electricity production by coal combustion has taken place in Israel, the United States and the rest of the world. As a result, a large amount of CCPs are created that include bottom ash, fly ash, flue gas desulfurization (FGD) gypsum and other combustion products. In Israel 100,000 tons of fly ash (10% of total CCPs) are produced each year and in the US a total of 123 million tons of CCPs are produced each year with 71 million tons of fly ash, 18 million tons of bottom ash and 12 million tons of FGD gypsum. Many new scrubbers are being installed and will come on-line in the next 2 to 10 years and this will greatly expand the amount of FGD gypsum. One of the main substrates used in Israel for growth media is volcanic ash (scoria; tuff). The resemblance of bottom coal ash to tuff led us to the assumption that it is possible to substitute tuff with bottom ash. Similarly, bottom ash and FGD gypsum were considered excellent materials for creating growth mixes for agricultural and nursery production uses. In the experiments conducted, bottom ash was studied in Israel and bottom ash, fly ash and FGD gypsum was studied in the US. Major Achievements: In the US, mixes were tested that combine bottom ash, organic amendments (i.e. composts) and FGD gypsum and the best mixes supported growth of tomato, wheat and marigolds that were equal to or better than two commercial mixes used as a positive control. Plants grown on bottom ash in Israel also performed very well and microelements and radionuclides analyses conducted on plants grown on bottom coal ash proved it is safe to ingest the edible organs of these plants. According to these findings, approval to use bottom coal ash for growing vegetables and fruits was issued by the Israeli Ministry of Health. Implications: Bottom coal ash is a suitable substitute for volcanic ash (scoria; tuff) obtained from the Golan Heights as a growth medium in Israel. Recycling of bottom coal ash is more environmentally sustainable than mining a nonrenewable resource. The use of mixes containing CCPs was shown feasible for growing plants in the United States and is now being evaluated at a commercial nursery where red sunset maple trees are being grown in a pot-in-pot production system. In addition, because of the large amount of FGD gypsum that will become available, its use for production of agronomic crops is being expanded due to success of this study.
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Lalovic, Ivan, Fernando Miralles-Wilhelm, Philipp Grötsch, Sara de Moitié, Adam Belmonte, Jihoon Lee, Raúl Muñoz Castillo et al. Remote Sensing Analysis of Water Quality in Four Waterbodies of Latin America. Editado por Eveline Vasquez e José Rosales. Banco Interamericano de Desarrollo, janeiro de 2024. http://dx.doi.org/10.18235/0005498.
Texto completo da fonteResumo:
The pilot study introduces remote sensing methods for monitoring water quality to measure, understand, and manage impacts on vulnerable water bodies that are part of the IDBs Water and Sanitation portfolio. The water bodies selected for this study include: Guanabara Bay in Río de Janeiro, Brazil; Lake Titicaca in Bolivia and Peru; Ypacaraí Lake near Asunción, Paraguay; and the Río Reconquista Basin near Buenos Aires, Argentina. This study focuses on the development and implementation of an automated remote sensing data processing chain enabling detection of phytoplankton abundance (chlorophyll-a) as a proxy for pollution by organic and inorganic nutrients, as well as sediments (and turbidity or water clarity), which are the major water quality issues identified across the IDBs Water and Sanitation portfolio. In addition to providing a baseline assessment of water resources at four select locations over time, the collected remote sensing data will be used to rapidly assess changes in water quality conditions resulting from socioeconomic changes introduced by local and regional responses to the Covid-19 pandemic and associated lockdown conditions. Remote sensing applied to water quality monitoring is a valuable emerging technology that can provide geospatial data about water quality and nutrient, bacterial, and industrial pollution from urban and rural sources. The methodology presented in this paper uses cloud computing, which allows rapid monitoring deployment and scalable coverage across numerous watersheds and geographies. Although this paper presents a comprehensive analysis of this entirely new source of water quality data across the sites and locations of interest, a more detailed analysis can be performed by examining different timeframes (e.g., entire data set or monthly aggregates) within these watersheds. Additional insights may be revealed by further combining the water quality data sets of this work with other sources of information, including local sensors, information from water and sanitation utilities, and a more detailed analysis of the timing of location conditions and their local impacts.
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Cohen, Shabtai, Melvin Tyree, Amos Naor, Alan N. Lakso, Terence L. Robinson e Yehezkiel Cohen. Influence of hydraulic properties of rootstocks and the rootstock-scion graft on water use and productivity of apple trees. United States Department of Agriculture, 2001. http://dx.doi.org/10.32747/2001.7587219.bard.
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This one year exploratory project investigated hydraulic architecture of apple dwarfing rootstocks. The hypothesis was that hydraulic conductance is correlated with rootstock vigor. A previous study of trees on three rootstocks in Israel showed that dwarfed trees used less water than un-dwarfed trees. Analysis showed that if the tree maintains leaf water potentials above minimum values, then this implies that the dwarfed trees have lower leaf conductance, which may also be the cause of dwarfing. The current project studied small 2-year old unworked rootstock trees, and full sized trees bearing commercial yields. In both cases hydraulic conductance was determined with two methods - the non-destructive evaporative flux (EF)-leaf water potential (L WP) method, and a destructive method in which water was forced through the plant at known pressure using the "high pressure flow meter" (HPFM). Detailed work allowed measurement of conductance of the rootstock-scion union. This was achieved both with the HPFM and with the EF-LWP methods, the former in the US and the latter in Israel. Direct measurements of leaf conductance were made, and carbon isotope ratios ( d ¹³ C) were determined for leaves sampled at the end of the season. The latter can indicate sustained differences in leaf conductance behavior. HPFM and EF-LWP methods did not give the same results. In the small plants results were similar in magnitude, but not significantly correlated. In large trees, EF- L WP measurements were a fraction of those obtained with the HPFM. The latter indicates that some of the xylem is not normally functional but transports water when pressurized. Additional experimental work targeted this result. Xylem was stained before and after perfusion with water at high pressure. This showed that at least for one rootstock a significant amount of xylem was blocked before perfusion. The "air method" for determining xylem vessel properties was improved and employed. Length, radius and density of xylem vessels of different rootstocks were found to be similar, and significant differences found were not clearly related to rootstock vigor. Measurements in the commercial orchard in Israel showed that the graft union in a dwarfing rootstock was a large obstacle for water transport (i.e. had a high resistance). This apparently led to low leaf conductance to water vapor, as indicated by lower d ¹³ C, which implies low internal CO ₂ concentrations. In the US orchard, d ¹³ C in 2001 was correlated with rootstock vigor, and significant differences were found in leaf conductance. However, the d ¹³ C differences were not observed in 2002, were opposite to those found in the Israeli orchard, and measurements of the graft union with the HPFM did not find large resistances. We speculate that the graft union is not necessarily a large impediment to water transport unless the scion starts to separate from the rootstock. It was concluded that significant differences in hydraulic conductance exist between different dwarfing rootstocks. These differences may be caused by differences in xylem properties and in the degree of cavitation, as well as resistance in the graft union. However, no general relationship to rootstock vigor was found. Therefore, hydraulic conductance alone cannot explain dwarfing, but may be one of two or more factors that lead to dwarfing. Future work should integrate more factors with hydraulic relations, e.g. nutrient and solute transport and production of hormones.
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LeDuc, Jamie, Ryan Maki, Tom Burri, Joan Elias, Jay Glase, Brenda Moraska Lafrancois, Kevin Peterson, David Vandermeulen e Ben Vondra. Voyageurs National Park interior lakes status and impact assessment. National Park Service, fevereiro de 2022. http://dx.doi.org/10.36967/nrr-2289923.
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Voyageurs National Park (VNP) is a water-based park that includes part or all of four large lakes and twenty-six smaller lakes commonly referred to as “interior lakes”. The 26 interior lakes of VNP are important aquatic resources with differing size and depth, water chemistry, trophic status, fish communities, and visitor use. Despite the remote location of these lakes, they have been impacted by multiple stressors, including contaminants and non-native species. This assessment provides key information in support of a science-based management plan for these lakes. The objectives of this assessment were to: 1) assess the status of each of the interior lakes and categorically rank the lakes from least to most impacted; 2) use the results to make specific science-based management and restoration recommendations for the most impacted lakes; and 3) make general recommendations that may be useful in managing all of Voyageurs National Park’s interior lakes. When all factors considered in this analysis (water quality, fish mercury concentrations, and fish community characteristics) were combined and assessed, thirteen lakes were classified as most impacted, nine as moderately impacted, and three as least impacted. Although nearly half of the lakes were classified as most impacted in this assessment, many of these lakes are in excellent condition compared to other lakes in the region. The factor-by-factor impact status of the lakes was considered to help describe the condition of the lakes and the potential for restoration. No local management options were identified to mitigate the mercury contamination in these lakes as research has shown the sources of the contamination to arrive from regional and global sources. Similarly, no management actions were identified to reduce nutrient concentrations in the lakes ranked most impacted for nutrient conditions as these are remote lakes with minimal or no development within their watersheds, and it was also noted that paleolimnological studies have shown that the nutrient status of the interior lakes was relatively unchanged from pre-European settlement conditions. Finally, for the lakes in which presumed introduced fish species are present, piscicides were considered as a potential management action. Piscicides were not recommended as a strategy to eradicate introduced fish species as it was determined that genetic conservation of the populations of native fish species still present in these lakes was more valuable than eradicating the introduced species.
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Hackbarth, Carolyn, e Rebeca Weissinger. Water quality in the Northern Colorado Plateau Network: Water years 2016–2018 (revised with cost estimate). National Park Service, novembro de 2023. http://dx.doi.org/10.36967/nrr-2279508.
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Water-quality monitoring in National Park Service units of the Northern Colorado Plateau Network (NCPN) is made possible through partnerships between the National Park Service Inventory & Monitoring Division, individual park units, the U.S. Geological Survey, and the Utah Division of Water Quality. This report evaluates data from site visits at 62 different locations on streams, rivers, and reservoirs in or near ten NCPN park units between October 1, 2015 and September 30, 2018. Data are compared to state water-quality standards for the purpose of providing information to park managers about potential water-quality problems. The National Park Service does not determine the regulatory status of surface waters; state water quality agencies determine whether waters comply with the Clean Water Act. Evaluation of water-quality parameters relative to state water-quality standards indicated that 17,997 (96.8%) of the 18,583 total designated beneficial-use evaluations completed for the period covered in this report met state water-quality standards. The most common exceedances or indications of impairment, in order of abundance, were due to elevated nutrients, elevated bacteria (E. coli), elevated water temperature, elevated trace metals, elevated total dissolved solids (and sulfate), elevated pH, and low dissolved oxygen. While some exceedances were recurring and may have been caused by human activities in the watersheds, many were due to naturally occurring conditions characteristic of the geographic setting. This is most apparent with phosphorus, which can be introduced into surface water bodies at elevated levels by natural weathering of the geologic strata found throughout the Colorado Plateau. Higher phosphorus concentrations could also be attributed to anthropogenic activities that can accelerate erosion and transport of phosphorus. Some activities that can increase erosional processes include grazing, logging, mining, pasture irrigation, and off-highway vehicle (OHV) use. Exceedances for total phosphorus were common occurrences at nine out of ten NCPN park units, where at least one site in each of these parks had elevated phosphorus concentrations. At these sites, high levels of nutrients have not led to algal blooms or other signs of eutrophication. Sites monitored in Arches National Park (NP), Black Canyon of the Gunnison NP (BLCA), Bryce Canyon NP (BRCA), Capitol Reef NP (CARE), Curecanti National Recreation Area (CURE), Dinosaur National Monument (DINO), and Zion NP (ZION) all had E. coli ex-ceedances that could be addressed by management actions. While many of these sites already have management actions underway, some of the actions necessary to bring these waters into compliance are beyond the control of the National Park Service. Changes to agricultural practices to improve water quality involves voluntary participation by landowners and/or grazing permittees and their respective states. This could be the case with lands upstream of several parks with E. coli contamination issues, including Red Rock Canyon (BLCA); Sul-phur, Oak, and Pleasant creeks (CARE); Blue Creek and Cimarron River (CURE); Brush and Pot creeks (DINO); and North Fork Virgin River (ZION). Issues with E. coli contamination at Yellow Creek (BRCA) seemed to be resolved after the park boundary fence downstream of the site was repaired, keeping cattle out of the park. At North Fork Virgin River, E. coli exceedances have been less frequent since the State of Utah worked with landowners and grazing permittees to modify agricultural practices. Continued coordination between the National Park Service, state agencies, and local landowners will be necessary to further re-duce E. coli exceedances and, in turn, improve public health and safety in these streams. Selenium concentrations in Red Rock Canyon (BLCA) continued to exceed the state aquat-ic-life standard at both the upstream and downstream sites. Although selenium weathers naturally from bedrock and...
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McFarlane, Aaron, Nia Hurst, Carina Jung e Charles Theiling. Evaluating soil conditions to inform Upper Mississippi River floodplain restoration projects. Engineer Research and Development Center (U.S.), abril de 2024. http://dx.doi.org/10.21079/11681/48451.
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The US Army Corps of Engineers (USACE) has designed and constructed thousands of acres of ecosystem restoration features within the Upper Mississippi River System. Many of these projects incorporate island construction to restore geomorphic diversity and habitat, including floodplain forests. Soils are the foundation of the ecological function and successful establishment of floodplain forests as they are the basis through which plants obtain water and nutrients and provide critical ecosystem services. To improve floodplain forest island restoration outcomes, three natural and four recently (<10 years) constructed restoration sites were studied to compare soil physical, chemical, microbial, and fungal characteristics. Constructed islands had lower soil organic matter and dissolved organic carbon and differed in nutrient concentrations, bacterial assemblages, and fungal communities compared to reference sites. However, soil enzyme activity and some microbial community characteristics were functionally similar between the natural and created sites. Results align with previously established restoration trajectory theories where hydrological and basic microbial ecosystem functions are restored almost immediately, but complex biologically mediated and habitat functions require more time to establish. Data from this and future studies will help increase the long-term success of USACE floodplain forest restoration, improve island design, and help develop region-specific restoration trajectory curves to better anticipate the outcomes of floodplain forest creation projects.