Dissertationen: „Suitability of water“

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Patrick, Eric Clement. „Determining runoff potential for assessing suitability for water harvesting“. Thesis, University College London (University of London), 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.272950.

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Tolera, Habtamu Haile. „Suitability of local materials to purify Akaki Sub-Basin water“. Karlsruhe : Univ.-Verl. Karlsruhe, 2007. http://www.uvka.de/univerlag/volltexte/2007/253/.

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Haile, Tolera Habtamu. „Suitability of local materials to purify Akaki Sub-Basin water“. Karlsruhe : Universitätsverlag, 2007. http://www.uvka.de/univerlag/volltexte/2007/253/.

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Cruz, Rex Victor O., und Peter F. Ffolliott. „A Geographically-Based Land Use Suitability Assessment and Land Capability Classification“. Arizona-Nevada Academy of Science, 1990. http://hdl.handle.net/10150/296434.

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From the Proceedings of the 1990 Meetings of the Arizona Section - American Water Resources Association and the Hydrology Section - Arizona-Nevada Academy of Science - April 21, 1990, Arizona State University, Tempe, Arizona

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Webster, Jack Ryan. „Suitability of the Kalina Cycle for Power Conversion from Pressurized Water Reactors“. BYU ScholarsArchive, 2018. https://scholarsarchive.byu.edu/etd/6882.

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The primary objective of this work is to determine the Kalina cycle's suitability for thermal power conversion from a pressurized water reactor. Several previous papers have examined this application, but these either lack proof of concept or make unfeasible assumptions. This work expands current knowledge by simulating the Kalina cycle and comparing it to current pressurized water reactor Rankine cycles in order to identify which is more efficient. Prerequisite to the modeling is a simulation tool capable of modeling the thermodynamics of ammonia/water mixtures. Instead of using an existing program, a new one called Clearwater is used. This tool is based on a preexisting Gibbs free energy "super" equation of state. Algorithms for vapor-liquid equilibrium calculations and phase identification are presented. Clearwater will be distributed online as open-source code to aid future developers of ammonia/water power and refrigeration cycles. A comparison of single-stage Kalina and Rankine cycles driven by heat from PWR core coolant suggests that the Kalina cycle is not well suited to the application. Any benefit from the Kalina cycle's ability to match temperature profiles in the boiling region of the steam generator is outweighed by other drawbacks. These include the cycle's 1) increased turbine exhaust pressure and 2) lower average heat absorption temperature caused by its working fluid's relatively high liquid heat capacity, both of which lower efficiency. Having concluded this, an attempt is made to quantify the conditions under which the Kalina cycle produces more power than the Rankine cycle. Both cycles are optimized for a range of heat source inlet and outlet temperatures between 350 â„ƒ and 525 â„ƒ. When both cycles absorb the same amount of heat from the source"”i.e., when source outlet temperature is constrained"” the Kalina cycle is less effective for small source temperature drops. When outlet temperature is unconstrained, the Kalina cycle outperforms the Rankine cycle for all but the lowest inlet temperature. This is due to the Kalina cycle's non-isothermal boiling profile, which allows it to absorb low temperature heat at relatively high pressure. Because of its isothermal boiling profile, the Rankine cycle cannot capture low temperature heat as effectively, so it performs worse over large, unconstrained source temperature drops.

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[Verfasser], Habtamu Haile Tolera. „Suitability of local materials to purify Akaki Sub-Basin water / von Habtamu Haile Tolera“. Karlsruhe : Univ.-Verl. Karlsruhe, 2007. http://d-nb.info/985277548/34.

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Tong, Ruiju [Verfasser]. „Influence of Seabed Topography on Cold-Water Coral Distribution and Habitat Suitability / Ruiju Tong“. Bremen : IRC-Library, Information Resource Center der Jacobs University Bremen, 2013. http://d-nb.info/1037013565/34.

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Preece, Ellen P. „Suitability of coho salmon habitat in Maddox and Carpenter Creeks, Skagit Delta, Washington“. Pullman, Wash. : Washington State University, 2010. http://www.dissertations.wsu.edu/Thesis/Spring2010/e_preece_060810.pdf.

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Thesis (M.S. in natural resource sciences)--Washington State University, May 2010.
Title from PDF title page (viewed on July 19, 2010). "Department of Natural Resource Sciences." Includes bibliographical references (p. 43-47).

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Kraft, Maggi. „Optimizing Barrier Removal to Restore Connectivity in Utah’s Weber Basin“. DigitalCommons@USU, 2017. https://digitalcommons.usu.edu/etd/6885.

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River barriers, such as dams, culverts and diversions are important for water conveyance, but disrupt river ecosystems and hydrologic processes. River barrier removal is increasingly used to restore and improve river habitat and connectivity. Most past barrier removal projects prioritized individual barriers using score-and-rank techniques, neglecting the spatial structure and cumulative change from multiple barrier removals. Similarly, most water demand models satisfy human water uses or, only prioritize aquatic habitat, failing to include both human and environmental water use benefits. In this study, a dual objective optimization model identified in-stream barriers that impede quality-weighted aquatic habitat connectivity for Bonneville cutthroat trout. Monthly streamflow, stream temperature, channel gradient and geomorphic condition were indicators of aquatic habitat suitability. Solutions to the dual objective problem quantify and graphically present tradeoffs between quality-weighted habitat connectivity and economic water demands. The optimization model is generalizable to other watersheds, but it was applied as a case study in Utah’s Weber Basin to prioritize removal of environmentally-harmful barriers, while maintaining human water uses. Modeled results suggest tradeoffs between economic costs of removing barriers and quality-weighted habitat gains. Removing 54 in-stream barriers increases quality-weighted habitat by about 160 km and costs approximately $10M, after which point the cost effectiveness of removing barriers to connect river habitat slows. In other words, there is decreasing benefit of removing barriers, so that after removing the first 54 barriers, it costs more to connect more high-quality habitat. Removing reservoirs or diversions that result in large economic losses did not substantially increase habitat. This suggests that removing numerous small barriers results in greater increases in habitat for the same removal costs, without significant water scarcity losses. The set of barriers prioritized for removal varied monthly depending on limiting habitat conditions for Bonneville cutthroat trout. The common barriers removed in the model were identified to communicate the most environmentally harmful barriers to local stakeholders and inform decision-making. Additionally, limiting the budget or number of barrier removal projects resulted in a different set of barriers removed. This research helps prioritize barrier removals and future restoration decisions in the Weber Basin although the model formulation is generalizable to other watersheds. Available data and a simplified approach limit the scope of this model. The modeling approach expands current barrier removal optimization methods by explicitly including economic and environmental water uses.

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Sadeghi, Saviz. „Multi-criteria Spatial Evaluation and Modelling of Farm Dam Site Suitability for Water Harvesting and Conservation“. Thesis, The University of Sydney, 2015. http://hdl.handle.net/2123/16261.

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This study presents a conceptual model designed to identify and rank potential areas for siting farm dams in a section of the Hawkesbury-Nepean catchment in western Sydney, Australia. The method takes into account environmental site assessment criteria using a decision-making method known as the Analytic Hierarchy Process (AHP). Spatial data is processed by applying GIS and potential sites are ranked by a multi-criteria evaluation based on meteorologic, hydrologic, topographic, agronomic and pedologic criteria. Particular to this study is the application of the SCS-CN method using curve numbers (CN) slightly modified for Australian conditions (CNMAC) for estimating runoff along with the original NCRS-CN values for comparative purposes. The use in this research of CNMAC has indicated modified CNs could be applied successfully in Australia especially in areas with limited physical data. Spatially-explicit sensitivity analysis was used to examine the model’s robustness to the sensitivity of criteria weights resulting from AHP pair-wise comparisons. Application of the One-At-a-Time (OAT) method (Chen et al.’s (2010, 2013)) demonstrated runoff has the highest impact on the evaluation results. Most of the study catchment showed a relatively stable suitability class; therefore, the model (SSMFD) was relatively robust and flexible in identifying suitable sites. The study then focussed on climate change impacts through annual rainfall patterns and their influence on the hydrology of the catchment and the model. Investigating 130 years of rainfall pattern indicated model low sensitivity to annual rainfall amount. In addition, changing the input data resolution used in SSMFD indicated that detailed outcomes were influenced by the resolution of input datasets. According to the SCS-CN method, results indicated the most decisive factor is CN values, consequently, soil and land cover are two crucial parameters and have the greatest impact on the model performance.

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Sidi, Purnomo. „Investigating the suitability of biomass Eichhornia crassipes as a lost circulation material in water-based drilling muds“. Thesis, University of Aberdeen, 2018. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=239377.

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This study investigated the performance of the biomass Eichhornia crassipes plant (ECP) as an additive in water-based drilling-mud. ECP is an invasive plant of fresh water ecosystems, so its use in drilling operations provides a low-cost, sustainable option that has off-site environmental benefits. Mechanical tests were conducted on ECP fibres to determine their stiffness under dried and water-wet conditions. Initial tensile tests on nylon fibre determined potential experimental artefacts with the experimental approach. The dried fibres had a water content of 8.163 wt. % (SE 0.636), whereas the wet fibres were 93.43 wt.% (SE 0.294). Water wet fibres had a lower modulus of elasticity than dried fibres and therefore, dried fibres have less tensile strength than wet fibres (Mean = 45.16 MPa; SE = 5.023; N = 41). Rheological properties of bentonite-based drilling muds amended with ECP at different concentrations were also studied. These muds were prepared by mixing ECP fragments at various concentrations (%w/w) with bentonite-water solutions and aged under ambient conditions. Mud viscosity gradually decreased with increasing shear rate, showing characteristic shear-thinning behaviour. Lost circulation of bentonite-water solutions mixed with ECP fragments were assessed with static filtration experiments. Slots and single perforated discs were designed to mimic fractures surrounding drilled boreholes. From a broad range of testing conditions, it was found that ECP fibres significantly decrease lost circulation by bridging fractures. An optimal concentration of 0.83 % by weight of ground plant stalks mixed with 6.28% bentonite in water improved rheology and filtration properties. A bridging gap model for a single fibre showed that ground stalk was less deflected than dried fibre when bridged an opening fissure. The findings of this research create an alternative to use ECP as lost circulation material in oil and gas drilling operations.

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Ngcobo, Silindile. „The suitability of estrogen and androgen bioassays for the measurement of endocrine activity in different water matrices“. Diss., University of Pretoria, 2017. http://hdl.handle.net/2263/63041.

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Endocrine disrupting chemicals (EDCs) are ubiquitous in the environment and their presence in water bodies is documented. They discharge into surface water (SW) unmonitored, posing a threat to both aquatic and terrestrial lives. This is a challenge as not all populations have access to treated drinking water (TDW). The EDC contaminated serves as a route of exposure, together with ineffective treatment plants. Given the complexity of the endocrine system, EDCs may mimic or antagonise natural hormones or disrupt their synthesis, metabolism and excretion. The associated health effects include testicular dysgenesis syndrome, metabolic disorders and cancers. Policy and internationally standardised test methods are however sti ll limited. This study therefore aimed to assess the suitability of two assays used for screening estrogenic activity and one for androgenic activity in different water sources. The study consisted of two phases. In phase 1, water sample (tap, surface and treated wastewater) were collected from a catchment area in Pretoria. The samples and a spiked MilliQ laboratory water sample were extracted with solid phase extraction (SPE) and sent to Germany for distribution to participating laboratories. Samples (n=24) from six different countries were received to test for androgenic activity in the MDA-kb2 reporter gene assay. In phase 2, SW and TDW samples were collected from April 2015 until March 2016. The samples were filtered, extracted using SPE and assayed with the YES assay, T47D-KBluc reporter gene assay for estrogenic activity and MDA-kb2 reporter gene assay for androgenic activity. In phase 1, androgenic activity was detected in 4 out of 24 (21%) samples and ranged from 0.23 ± 0.040 ng/L to 0.008 ± 0.001 ng/L DHTEqs. In phase 2, estrogenic activity was detected in 16 out of 24 (67%) SW samples in the T47DKBluc reporter gene assay and ranged from 0.31 ± 0.05 pg/L to 10.51 ± 5.74 pg/L EEqs. It was below the detection limit (dl) in the YES assay. Androgenic activity was detected in 4 out of 24 (17%) SW samples, ranging from 0.0033 ± 0.0050 ng/L to 0.090 ± 0.040 ng/L DHTEqs. Androgenic and estrogenic activity was higher i n pretreatment samples compared to post-treatment in both treatment plants. In phase 1, the MDA-kb2 reporter gene assay was successfully applied to water samples from different sources. Androgenic activity was highest in treated wastewater. In phase 2, treatment plants proved to be effective in removing estrogens detected in the SW samples, as the TDW samples were below the dl. Estrogenic activity is within the ranges reported in other studies. Positive samples were below the 0.7 ng/L proposed trigger value for health risk assessments. Detected androgenic activity was lower in TDW samples compared to the SW samples supplying the two treatment plants indicating that they were both effective in removing the androgenic activity detected. Few studies have reported androgenic activity in tap water. This study strengthens the argument for using a battery of assays when monitoring endocrine activity as EDCs occur at low concentrations in mixtures.
Dissertation (MSc)--University of Pretoria, 2017.
School of Health Systems and Public Health (SHSPH)
MSc
Unrestricted

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Alataway, Abed. „Suitability of waste water for irrigation in Saudi Arabia : analysis of public perceptions and quantitative microbial risk assessment“. Thesis, University of Newcastle Upon Tyne, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.601759.

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Wastewater reuse for irrigated practice is un alternative solution in which food production can be improved especially in the arid-region where freshwater resources are often limited However; the potential public health risk associated with wastewater reuse remain a major concern. as well as public perceptions towards wasteater. This research was conducted in two main agricultural cities within the Saudi Arabia

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Bilkovic, Donna Marie. „Assessment of spawning and nursery habitat suitability for American shad (Alosa sapidissima) in the Mattaponi and Pamunkey Rivers /“. W&M ScholarWorks, 2000. http://www.vims.edu/library/Theses/Bilkovic2000.pdf.

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15

Lower, Steven S. „The effects of soil nutrients and water on the suitability of silky willow for the imported willow leaf beetle /“. Thesis, Connect to Dissertations & Theses @ Tufts University, 2002.

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Thesis (Ph.D.)--Tufts University, 2002.
Adviser: Colin M. Orians. Submitted to the Dept. of Biology. Includes bibliographical references (leaves 111-127). Access restricted to members of the Tufts University community. Also available via the World Wide Web;

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Hofstedt, Charlotta. „Wastewater use in Agriculture in Andhra Pradesh, India : An evaluation of irrigation water quality in reference to associated health risks and agricultural suitability“. Thesis, Uppsala University, Department of Earth Sciences, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-88888.

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Användandet av obehandlat avloppsvatten inom jordbruket är en växande företeelse i många delar av världen. Speciellt i vattenfattiga områden där avloppsvattnet ses som en värdefull och pålitlig resurs. Det höga näringsinnehållet minskar behovet av konstgödsel och detta ökar böndernas inkomster. Men med användandet av avloppsvattnet följer vissa hälsorisker. Bland annat har man sett en högre förekomst av inälvsmaskar hos bönder som använder orenat avloppsvatten jämfört med de som använder rent vatten. Den här vattenkvalitetstudien har utförts längs floden Musi i Andhra Pradesh, Indien. Musi rinner igenom staden Hyderabad och mycket av stadens avloppsvatten dumpas i floden. Nedströms Hyderabad används detta vatten för bevattning. Längs med floden är dammar byggda, för att avleda vattnet i bevattningskanaler. Reservoirer bildas då flödeshastigheten minskar. Studieområdet sträcker sig från Hyderabad och 28.7 km nedströms. Hypotesen var att reservoirerna fungerar som biodammar och syftet var att kvantifiera dammarnas inverkan på vattenkvaliteten och utvärdera dess lämplighet utifrån ett hälso- och jordbruksperspektiv. Inom studieområdet är reningen med avseende på BOD, Nematoder och E coli 86,9%, 99,9% respektive 99,9%. Trots att reningen är så hög överstiger Nematod- och E coli-koncentrationerna Världshälsoorganisationens riktlinjer och utgör en hälsorisk för bönder och konsumenter. Syre- och salthalt ökar nedströms och den höga salthalten kan ha negativ inverkan på jordbrukets avkastning. Genom att titta på reningsmönster och förändring av olika vattenkvalitetsparametrar är en av slutsatserna av detta arbete att reningen i dammarna motsvarar den rening som sker i de anaeroba bassängerna i ett biodammsystem.

The use of untreated domestic sewage in agriculture is a growing practice in many parts of the world. It is being looked upon as a valuable and reliable resource in water scarce communities. Wastewater is usually rich in nutrients and the use results in high yields without the need for artificial fertilisers. But with the use of untreated wastewater follows a number of associated health risks, e.g. a higher prevalence of helminth infections has been seen among wastewater users compared to non-users. This water quality study was performed along the River Musi in Andhra Pradesh, India. The Musi River flows through the city of Hyderabad carrying the most of the town’s wastewater. Downstream of Hyderabad the wastewater is used by farmers for irrigation. Along the river weirs are constructed which diverts the irrigation water into canals and reservoirs are formed where the flow velocity slows down. The study area stretches from Hyderabad and 28.7 km downstream. The hypothesis was that the existing irrigation infrastructure acts like Wastewater Stabilisation Ponds and the aim was to quantify the impact of the weirs on water quality and to evaluate the irrigation water quality in reference to associated health risks and agricultural suitability. Within the study area the BOD, E coli and Nematode removals were 86.9%, 99.9% and 99.9% respectively. Despite the high removal the E coli and Nematodes, the concentrations exceed WHO guidelines for unrestricted and restricted irrigation, and there exists an excess risk of intestinal nematode- and enteric infections for farmers. Dissolved oxygen and salinity increases downstream and due to the high salinity farmers could experience reduced crop yields. By looking at removal patterns, and the change in water quality parameters, the conclusion can be made that the reservoirs act like anaerobic ponds in a Wastewater Stabilisation Pond system.

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Nolakana, Pamela. „Geochemical assessment of groundwater quality and suitability for drinking and irrigation purposes in Newcastle, Kwazulu-Natal, South Africa“. University of the Western Cape, 2016. http://hdl.handle.net/11394/5019.

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>Magister Scientiae - MSc
Groundwater is one of the most valuable natural resources on earth and it forms an important part of the total water resources of South Africa. For this reason, this resource should be monitored and controlled on a regular basis. The study was conducted in Newcastle, in the KwaZulu-Natal province of South Africa. The aim of this study was to assess groundwater quality geochemically and determine its suitability for domestic and irrigation purposes. For the purpose of this study 31 samples were collected from 31 boreholes in and around the town of Newcastle. The samples were analysed for Magnesium (Mg2+), Calcium (Ca2+), Sodium (Na+), Potassium (K+), Chloride (Cl-), Sulfate (SO42-), Bicarbonate (HCO3-), Nitrate (NO3-), Fluoride (F-) (pH, TDS and Ec. The SAQWG (DWAF, 1996) and the WHO (2011) water standards were used as the basis of evaluating the suitability of groundwater for drinking purposes. For irrigation, Electrical Conductivity (EC), Sodium Percent (Na %), Sodium Adsorption Ratio (SAR), Residual Sodium Carbonate (RSC), Kelly’s Ratio (KR), Magnesium Ratio (MR) and Permeability Index (PI) were used to evaluate suitability. Classical hydro-chemical methods together with multivariate statistical methods were used to further understand the composition controlling processes. Lastly, the spatial distribution of the results was presented using ArcGIS. The results showed that the groundwater is alkaline in nature and that most of the samples are within the permissible range of both SAWQG (DWAF, 1996) and WHO (2011). Few samples showed concentration of Na+, Cl-, SO42- , F- and TDS above the guideline value as per WHO (2011) standards. The order of abundance of major ions in the groundwater, based on their mean values is as follows: Na+>Ca2+>Mg2+>K+ and HCO3->SO42- >Cl->NO3-. Classical hydro-chemical methods revealed four hydro-chemical facies in the study area, which are Ca-Mg-HCO3, Na-HCO3, Ca-Na-SO4-HCO3 and Na-Cl. The major ion chemistry analysis revealed that the main composition controlling processes in the study area is rock-water interaction. It further revealed that the ionic concentration is due to silicate weathering, carbonate weathering, cation exchange, gypsum dissolution and halite dissolution. Factor analysis indicated three factors, which explained 79.71 % of the total variance in the water quality data. The first factor which accounted for the highest variance in the data was the Alkalinity factor, followed by the Hardness factor and the Anthropogenic factor which accounted for the least variance. The cluster analysis revealed five clusters and discriminant analysis showed that Na+, TH, HCO3- and SO42- discriminate these clusters by 96.8%. In conclusion, the study revealed that the groundwater in most of the boreholes in the study area is generally suitable for drinking and irrigation. This is with exception to boreholes 13 and 31 which showed concentrations higher than the permitted level by WHO (2011) standards of TDS, Na+, Cl-, SO42- and F-. Similarly, 45.16% the groundwater samples showed that the groundwater has high sodium hazard potential which makes water from these boreholes unsuitable for irrigation purposes without proper treatment. accounted for the least variance. The cluster analysis revealed five clusters and discriminant analysis showed that Na+, TH, HCO3- and SO42- discriminate these clusters by 96.8%. accounted for the least variance. The cluster analysis revealed five clusters and discriminant analysis showed that Na+, TH, HCO3- and SO42- discriminate these clusters by 96.8%.In conclusion, the study revealed that the groundwater in most of the boreholes in the study area is generally suitable for drinking and irrigation. This is with exception to boreholes 13 and 31 which showed concentrations higher than the permitted level by WHO (2011) standards of TDS, Na+, Cl-, SO42- and F-. Similarly, 45.16% the groundwater samples showed that the groundwater has high sodium hazard potential which makes water from these boreholes unsuitable for irrigation purposes without proper treatment.

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Santos, Luiza Gonçalves. „Índices de aptidão e de riscos climáticos para a cultura da cana-de-açúcar no Estado de Goiás e no Distrito Federal“. Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/11/11152/tde-28092015-103920/.

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Goiás e Distrito Federal têm papel importante na cultura canavieira brasileira, da qual GO é o segundo maior produtor. Na definição de aptidão e de riscos climáticos a essa cultura, a ocorrência natural de altos déficits hídricos, como ocorre no centro-oeste do país, tem um efeito preponderante sobre a produtividade, sendo determinante na elaboração de zoneamentos agroecológicos e de riscos para a cana-de-açúcar no Brasil, com a finalidade de orientação de datas de plantio e uso de irrigação que minimizem esse efeito. Com o objetivo de aprofundar o conhecimento e aplicabilidade de índices de aptidão e de riscos climáticos, neste trabalho foram utilizadas séries climáticas de 13 localidades de GO e DF, para estimativa de três índices baseados no balanço hídrico de Thornthwaite-Mather calculado por três formas: climatológico médio e sequenciais (climatológico e de cultura), para dois tipos de solo. O índice de aptidão climática (APClima) considerou o déficit acumulado no ciclo de plantio fornecido pelo BH sequencial climatológico e o índice de satisfação da necessidade de água (ISNA) no período crítico da cultura, simulando-se períodos de cultivo com duração de 12 meses (cana-planta), com plantios no primeiro decêndio dos bimestres do ano. Outros, dois índices de risco (IRClima; IRCultura) originaram-se dos BHs sequenciais, utilizando valores acumulados de DEF para a definição de classes de aptidão (apta, marginal e inapta). Também foram utilizados fatores de ponderação e porcentagem de ocorrência das classes de aptidão, gerando-se 5 classes de risco (de muito alto a muito baixo). Na definição das classes foram usados limites de DEF em duas formas, uma, tradicionalmente usada com valores de 200mm e 400mm; e uma ajustada de acordo com valores estimados a partir de correlação dos DEF do BH médio com aqueles gerados pelos balanços sequenciais (DEFcorr). Os resultados mostraram a dificuldade da escolha do índice mais indicado, pois embora tenha-se o BH como base dos três, eles são usados de formas diferentes, além de haver diferenças conceituais entre os mesmos. Entretanto, duas conclusões gerais servem para os índices: a) quando comparados entre si e com mesma forma de cálculo de DEF, não foram observadas diferenças acentuadas nos índices quando se usou CAD 95 ou 125mm/m para cada um dos dois solos adotados; b) o uso de DEFcorr permitiu visualizar um número maior de localidades e janelas de plantio no ano em relação ao zoneamento agroecológico adotado pelo Ministério da Agricultura, Pecuária e Abastecimento. O APClima mostrou-se interessante por permitir a indicação de necessidade de irrigação, seja de salvamento ou complementar, mas mostrou-se mais rígidos que os outro nessas indicações. Os índices originários dos BHs sequenciais (IRClima e IRCultura) levaram a cenários mais favoráveis, com o aumento de janela de plantio com menor risco por efeito de DEF, entretanto suas avaliações não incluem os efeitos da época de sua ocorrência, podendo subestimar os resultados do período seco do ano e demandando maiores estudos. A metodologia proposta no trabalho mostrou-se bastante interessante por permitir maiores informações, consideradas importantes para o planejamento de plantio na região.
The State of Goiás (GO) and Federal District (DF) have an important role in Brazilian sugarcane production, being the second largest producer in the country. In the case of risks and climate suitability to this crop, the natural occurrence of high water stress has major effect on yield, as occurs in the Midwest of the country, being decisive in the development of agro-ecological zoning and risks for sugarcane in the country. In order to understand and apply the climate suitability and risks indexes used in this study, climatic series of 13 localities of GO and DF have been utilized. Thus the Thornthwaite-Mather water balance (BH) was calculated in three ways: the normal climatological, the sequential climatological and the sequential of crop, for two types of soil. The climate suitability index (APClima) considered the cumulative water deficit DEF (potential minus actual evapotranspiration) in the crop cycle, provided by the sequential BH climatological and water requirement satisfaction index (ISNA) in the critical period of crop, simulating up growing seasons of 12 months, with plantations in the first ten days of each bimester of the year. Other two risk indices (IRClima; IRCultura) were originated from sequential BHs using accumulated DEF value to define the suitability classes. In the three indexes, both traditional limits of DEF (200mm and 400mm) as those estimated with adjusted values originated from correlation between the normal and the sequential balances (DEFcorr) were applied. The results showed the difficulty of choosing the best index because although they were based on the BH, there are conceptual differences between them. However, two general conclusions serve for the contents: a) when compared with each other, within the same form of DEF calculation, no pronounced differences have been observed when soil water holding capacity of 95 or 125mm/m was applied, on both types of soil; b) the use of DEFcorr allowed a greater number of localities and planting windows to have better indications, compared to the agro-ecological zoning adopted by the Ministry of Agriculture, Livestock and Supply. The APClima proved to be an interesting index, once it indicates the use of irrigation requirement, either saving or complementary, but it has shown to be more rigorous than the other indices. The indexes originated from sequential BHs (IRClima and IRCultura) led to more favorable scenarios, showing a longer planting window with less risk effect of deficit, although their ratings do not include the effects of the time of its occurrence, and could underestimate the results of dry season.

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Aza-Gnandji, Cocou Davis Ruben. „Salinity of irrigation water in the Philippi farming area of the cape flats, Cape Town, South Africa“. University of the Western Cape, 2011. http://hdl.handle.net/11394/2921.

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Magister Scientiae - MSc
This research investigated the nature, source and the spatial variation of the salinity of the water used for irrigation in the urban farming area of Philippi, which lies in the Cape Flats region of the Cape Town Metropolitan Area, South Africa. The irrigation water is mainly drawn from the Cape Flats aquifer, and pumped into ponds for eventual crop irrigation. Water samples were collected in summer and in winter from fifteen selected sites using standard water sampling procedures. Each site consisted of one borehole and one pond. The samples were routinely analyzed for salinity levels, and concentrations of major and minor ions. From the same boreholes and ponds, water was sampled in summer for isotope analysis to assess effects of evaporation on the water quality and salinity. Descriptive statistics were used to display the variation in range of specific ions in order to compare them with the recommended ranges. Geographical Information Systems analysis described the spatial distribution of the salinity across the study area, and hydrogeochemical analysis characterized the various waters and detected similarities between the water samples in the study area and other waters found in the Cape Flats region. In addition, the US salinity diagram classification of irrigation water developed by Richards (1954) was used to assess the current suitability of groundwater and pond water samples collected during the entire sampling period for irrigation activities. The research indicated that the concentrations of some ions such as chloride, nitrate, potassium and sodium exceeded in places in the study area, the target range values set by the Department of Water Affairs and Forestry (DWAF, 1996) and the Food and Agriculture Organization (Ayers and Westcot, 1985). It revealed that borehole and pond water were mostly brackish across the area regarding their total dissolved salts content, and fresh water was only found in the middle part of the study area. The research found that sea water does not intrude into the aquifer of the study area, and the accumulation of salts in groundwater and soil in the study area is mainly due to the agricultural activities and partially due to the natural movement of water through the geological formation of the Cape Flats region. The conceptual model of the occurrence of the salinization process supported these findings. From this investigation it is understood that the groundwater and pond water in the study area were generally suitable for irrigation purposes but they have to be used with caution as the vegetables are classified as sensitive and moderately sensitive to salt according to DWAF Irrigation water guidelines (1996). The quality of these waters was mainly affected by the land use activities.
South Africa

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Zeelie, Angelique. „Effect of biochar on selected soil physical properties of sandy soil with low agricultural suitability“. Thesis, Stellenbosch : Stellenbosch University, 2012. http://hdl.handle.net/10019.1/20344.

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Thesis (MScAgric)--Stellenbosch University, 2012
ENGLISH ABSTRACT: Biochar has been labelled to be a key factor in the global carbon mitigation act and has been described as the modern day equivalent (terra nova) to the terra preta dark earth soils of the Brazilian Amazon. Globally biochar has been evaluated as a means to improve soil fertility and to mitigate greenhouse gases (GHGs). Little research has however been published on the effects of biochar incorporation on soil physical properties. The objective of this study was to evaluate the effect of pine sawmill waste derived biochar (locally-produced via slow pyrolysis – 450°C) on selected soil physical properties, soil-water dynamics and crop production and- performance, when amended to a Kroonstad (Kd 1000 – Morgendal) soil form. This soil form is commonly found in the Western Cape area (South Africa) and can be classified as having low agricultural suitability for perennial- and annual crop species. Two pot trials were carried out in an atmospheric controlled greenhouse, where winter wheat and green beans respectively were planted, with five different application levels of biochar (0t/ha, 1t/ha, 10t/ha, 50t/ha and 200t/ha). Soil physical properties namely, water-stable aggregates, bulk density and water-retention capacity along with physiochemical characterisation of the sandy soil and biochar was determined. The water-use was monitored throughout the trials (evapotranspiration, volumetric water content and biomass water use efficiency, BWUE). The above- and below ground (specific leaf traits for the green bean and the root structural development for the winter wheat) biomass was collected and analysed at harvest. There was significantly higher volumetric water content measured for the 50t/ha and 200t/ha biochar treatments. This effect can be ascribed due to a change in the soil’s tortuosity and porosity where more meso- and micro-pores were present as the biochar rate increased. The same results were evident when a water-retention curve was established in vitro by means of the sandbox method. The bulk densities were only significantly lower for the 200t/ha biochar treatments. The wheat root systems differed greatly among the fertilised biochar treatments: the 50t/ha and 200t/ha treatments had a more complex fibrous root system (more extensive branching and thinner roots) than 0t/ha, 1t/ha and 10t/ha application levels. This is attributed to the increased water-holding capacity along with a reduction of N- and P availability with increasing addition of biochar. Several leaf traits were measured for the green bean crops; however the leaf nitrogen- and carbon content, chlorophyll content index (CCI) and carbon isotope fractionation yielded the most interesting findings. Concerning the fertilised biochar treatments, there was established that the 10t/ha treatments had the highest leaf nitrogen- and carbon content. The leaf chlorophyll content did not differ significantly between the fertilised biochar treatments; however a very interesting observation was evident regarding the measured leaf CCI for the unfertilised treatments. A decreasing trend and lower leaf CCI was measured as the biochar application levels increased. This effect was ascribed to be due to a decrease in N uptake by the plants as the biochar application increased, the C/N ratio also increased, and this leading to N immobilisation. The lowest leaf carbon isotope fractionation was measured for the 10t/ha fertilised treatments and is inversely correlated with BWUE and therefore endorses the conclusion that the 10t/ha biochar application had a positive effect on the long term water use efficiency for the green bean plants. Biochar promoted aggregation in the sand-rhizosphere interface for winter wheat, increased water-holding capacity and enhanced crop performance for green beans. The findings reported here provide new information on the effect of biochar on the structural development of sandy soil, combined with biochar- and root growth effects for winter wheat; along with detailed interpretations of specific leaf traits associated with crop production for commercial green beans. The addition of biochar at low application levels (approximately 1-10t/ha to 15 cm depth) increased the biomass yield and water use efficiency of the crop species. Besides long term carbon storage, biochar can have immediate positive effects on the physical properties of sand and plant growth.
AFRIKAANSE OPSOMMING: Biokoolstof word beskou as ‘n sleutel komponent rakende die wet op globale koolstofvermindering en is al beskryf as die moderne ekwivalent (terra nova) van die terra preta donker-aardgronde wat aangetref word in die Brasiliaanse Amasone. Wêreldwyd word biokoolstof tans geëvalueer met die doel om grondvrugbaarheid te verbeter asook kweekhuisgasse (KHG) se nadelige gevolge te verlig. Min navorsing was tot dus ver gedoen rakende die uitwerking met toediening van biokoolstof op grondfisiese-eienskappe. Die doel van hierdie studie was om die effek van biokoolstof, wat afkomstig is van denne-saagmeul-afval (plaaslik geproduseer is en d.m.v. stadige perolise - 450°C) te evalueer aangaande die volgende faktore: geselekteerde grondfisiese-eienskappe, grond-waterdinamika interaksie en die uitwerking op gewasproduksie; met toediening aan 'n Kroonstad (Kd 1000 - Morgendal) grondvorm. Hierdie grondvorm word as algemeen in die Wes-Kaap (Suid-Afrika) bestempel en kan geklassifiseer word as ‘n lae-geskiktheid landbougrond vir meerjarige- en eenjarige gewasse. Twee potproewe is uitgevoer onder beheerde atmosfeer in ‘n kweekhuis, waar winter koring en groenbone geplant is, met vyf verskillende behandelings van biokoolstof (0t/ha, 1t/ha, 10t/ha, 50t/ha en 200t/ha). Die volgende grondfisiese-eienskappe is ondersoek, naamlik water-stabiele aggregaat formasie, bulkdigtheid en waterhouvermoë, asook die fisiochemiese karakterisering van die sanderige grond en biokoolstof wat gebuik is. Waterverbruik is gedurende die proewe gekontroleer (evapotranspirasie, volumetriese waterinhoud en die biomassa se water verbruiksdoeltreffendheid, BWVD). Die bo- en ondergrondse biomassa, spesifiek die blaareienskappe van die groenboontjie en die strukturele ontwikkeling van die winter koring se wortels, is tydens die oes ondersoek en ontleed. Die volumetriese waterinhoud was betekenisvol, asook hoër vir die 50t/ha en 200t/ha behandelings. Hierdie effek word toegeskryf as gevolg van 'n verandering in die grond se kronkeligheid en porositeit; waar meer meso- en mikroporieë teenwoordig was soos die biokoolstof inhoud toegeneem het. Dieselfde resultate was verkry met die opstelling van ‘n water-retensie kurwe in vitro d.m.v. die Sandboks metode. Bulkdigtheid was slegs betekenisvol verskilled asook aansienlik laer vir die 200t/ha biokoolstof behandelings. Die koring se wortelstelsel het drasties verskil tussen die verskillende bemeste biokoolstof behandelings: die 50t/ha en 200t/ha behandelings het 'n meer komplekse en veselagtige wortelstelsel gevorm (hoër graad van vertakking en dunner wortels was aanwesig) as die 0t/ha, 1t/ha en 10t/ha behandelings. Die effek word toegeskryf aan die toenemende waterhouvermoë, tesame met 'n tekort aan N- en P-beskikbaarheid soos die biokoolstof toedieningshoeveelhede verhoog het. Verskeie blaareienskappe is gemeet vir die groenboon gewasse, maar die blaar stikstof- en koolstof-inhoud, chlorofil inhoud indeks (CII) en koolstof-isotoop fraksionering het die mees interessante bevindinge opgelewer. Die hoogste blaar stikstof-en koolstof-inhoud is gemeet vir die 10t/ha bemeste biokoolstof behandelings. Die blaar chlorofil inhoud het nie beduidend verskil tussen die bemeste biokoolstof behandelings nie, maar daar was egter 'n baie interessante waarneming vir die onbemeste biokoolstof behandelings. ‘n Tendens was aanwesig waar die CII afgeneem het soos die biokoolstof toedieningshoeveelheid ook afgeneem het vir die onbemeste behandelings. Die effek word toegeskryf as gevolg van 'n afname in N-opname deur die plant soos die biokoolstof toedieningshoeveelheid verhoog is en tot gevolg gehad het dat die C/N-verhouding ook toegeneem het, wat gelei het tot N-immobilisasie. Die laagste blaar koolstof-isotoop fraksionering was geassioseer met die 10t/ha bemeste biokoolstof behandelings en is omgekeerd gekorreleerd met BWVD en onderskryf dus die gevolgtrekking dat die 10t/ha biokoolstof behandeling 'n positiewe uitwerking het op die langtermyn waterverbruiksdoeltreffendheid vir groenboontjie plante. Biokoolstof het aggregasie bevorder binne die wortelsone, asook deurgans die waterhouvermoë verhoog en gewasproduksie verbeter. Hierdie bevindinge lewer nuwe inligting oor die effek van biokoolstof op die strukturele ontwikkeling van sanderige grond en die gekombineerde interaksie met biokoolstof toediening en hoe dit wortegroei beïnvloed van winter koring; asook 'n gedetailleerde interpretasie van spesifieke blaareienskappe wat verband hou met die produksie van gewasse vir kommersiële verbouing soos die groenboontjie. Die toediening van biokoolstof by die lae hoeveelhede (ongeveer 1-10t/ha tot op 15 cm diepte) het die opbrengs en waterverbruiksdoeltreffendheid van die gewasse verbeter. Behalwe vir die langtermyn koolstofvaslegging, kan biokoolstof toediening onmiddellike positiewe resultate teweeg bring aangaande die fisiese eienskappe van sandgronde en plantegroei.

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Ismail, Salim. „Investigation of the suitability of aquatic invertebrates as biological indicators for detecting the presence of Campylobacter spp. in recreational water supplies“. Thesis, University of Canterbury. Department of Plant and Microbial Sciences, 2000. http://hdl.handle.net/10092/4247.

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Campylobacter species, the most frequent cause of acute bacterial gastroenteritis in humans, are of worldwide significance. Drinking and recreational surface waters have been identified as a major vehicle of pathogenic Campylobacter spp. transmission to humans. Outbreaks of campylobacteriosis as well as sporadic cases have been reported both locally and internationally. However, in only a small proportion of cases has the responsible organism been isolated from the implicated water source. The inherent difficulties with isolation of Campylobacter spp. from environmental water sources make the development of more reliable, alternative isolation and detection methods a preferred option. In this study, the potential for aquatic invertebrates to act as biological indicators for detecting Campylobacter spp. from recreational water was investigated. The suspension and filter feeding strategies of aquatic invertebrates allowing them to concentrate Campylobacter cells to readily detectable levels within their tissues was explored. Sampling of water, mussels, cockles and snails from the Avon-Heathcote rivers and estuary revealed low isolation rates with no apparent correlation between Campylobacter presence in water and the invertebrates. Placement of freshwater mussels in the Avon and Heathcote rivers proved successful for isolation of Campylobacter spp., while marine mussels, cockles and snails routinely tested negative. Hence, the freshwater mussel was chosen as a candidate bio-indicator. In vitro (tank) experiments showed close correlation between Campylobacter detection in mussels and water. However, isolation of Campylobacter from mussels was deemed to be no better than testing the water itself. Environmental Campylobacter isolates were analysed by resistotyping, flaA PCR-RFLP typing and PFGE to determine relationships between isolates. Although very few isolates were found to be clonal, a high level of genetic relatedness was determined between isolates from the Avon and Heathcote rivers. This indicates a common source of input between these rivers, most likely to be from birds. A validation study for the use of the cadF virulence gene as a marker for PCR detection of pathogenic Campylobacter species was under taken. Although useful for distinguishing Campylobacter spp. in pure culture, this system was found to show a degree of unreliability for specific detection from environmental samples.

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Hyland, Sara Elizabeth. „Analysis of Sinkhole Susceptibility and Karst Distribution in the Northern Shenandoah Valley, Virginia: Implications for Low Impact Development (LID) Site Suitability Models“. Thesis, Virginia Tech, 2005. http://hdl.handle.net/10919/33148.

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Increased stormwater runoff due to urban development in the northern Shenandoah Valley (NSV) region of Virginia has prompted local officials and representatives to consider Low Impact Development (LID) as a stormwater management technique. LID is based on infiltrating stormwater runoff at the source through practices such as bioretention, rain gardens, and grass swales. The karst terrain that underlies the Shenandoah Valley presents a major barrier to the use of LID. Infiltration of surface runoff in karst landscapes may threaten groundwater quality and the stability of the bedrock. In 2004 the Center for Geospatial Information Technology (CGIT) at Virginia Tech developed an LID site suitability model for the NSV region incorporating karst as a key component in distinguishing unsuitable from suitable conditions for LID. But, due to the difficulty of mapping karst, the karst layer used in the site suitability model is very coarse in resolution, based primarily on carbonate versus non-carbonate rock. This study uses a 1:24,000 scale sinkhole map derived from sinkhole boundaries identified by geologist David Hubbard (1984) of the Virginia Department of Mines and Minerals (DMME) to develop a more detailed karst map for a sub-watershed of the NSV region. The analysis uses geospatial techniques to determine the relationship between sinkhole distribution and four major landscape factors: bedrock type, soil depth to bedrock, proximity to geologic faults, and proximity to surface streams. The analysis identified three major trends in sinkhole occurrence: (1) sinkholes are more abundant in relatively pure carbonate rocks of Ordivician age; (2) sinkhole occurrence increases with proximity to fault lines; and (3) sinkholes are sparse near streams, most abundant 600 to 1400 feet away from surface streams. Based on these findings a sinkhole susceptibility index was produced using weighted overlay analysis in ArcGIS. The sinkhole susceptibility index provides a more detailed karst layer for the LID site suitability maps and can be used by the NSV region as a predictive tool for future sinkhole occurrence.
Master of Science

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Randall, Kevin L. „A Geologic and Hydrochemical Investigation of the Suitability of Central Utah's Navajo Sandstone for the Disposal of Saline Process Water and CO2“. DigitalCommons@USU, 2009. https://digitalcommons.usu.edu/etd/367.

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Salt water is produced from the Ferron Sandstone Member of the Mancos Shale in central Utah as part of the production of coalbed methane (CBM) and is disposed of by injection predominantly into the Navajo Sandstone between 4,500 feet to 7,300 feet and is considered to be a hazardous waste. Local government agencies are concerned about the potential impacts on shallow groundwater because of this disposal method. Water samples were gathered from four shallow water-supply wells, and nine salt water disposal (SWD) wells to compare hydrochemistries as an indicator of potential mixing. Shallow water-supply wells are likely recharged by local precipitation while the source of CO2 is from atmospheric and/or soil CO2 gas and comparatively, are low in total dissolved solids. Carbonate mineral dissolution is the source of CO2 in the SWD wells and is exceptionally high in TDS. The SWD water appears to be old water and displays an evaporative signature. A geologic analysis was conducted for the Drunkards Wash gas field using 479 digital gas well logs. Three subsurface faults were identified with one fault in the north and the other two in the central part of the gas field near the eastern and western flanks. These faults were further confirmed by comparing average monthly gas and water production from the first 24 months in these faulted areas to adjacent control areas. Areas near faults reveal two to six times greater gas production than that of the associated control areas, and water production is greater by nearly an order of magnitude. This difference is likely due to the fracturing associated with the damage zone near the faults allowing for increased flow of gas and water. Due to the high injection pressures the vertical hydraulic gradient has been reversed from downward to upward. However, due to the thick sequences of shale separating the disposal aquifers and the shallow aquifers the estimated time required for the disposal waters to migrate to the surface would be at least 2,000 years. I conclude that the saline waters produced from the Ferron Sandstone are being safely sequestered in deeply buried, extensive and geologically-sealed aquifers.

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Haegele, Jason Wade. „Maize (Zea mays L.) kernel development, suitability for dry-grind ethanol production, and susceptibility to aflatoxin accumulation in relation to late-season water stress“. [Ames, Iowa : Iowa State University], 2008.

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Teramoto, Edson Roberto. „Avaliação e aplicação de modelos de estimativa de produção de cana-de-açúcar (Saccharum spp) baseados em parâmetros do solo e do clima“. Universidade de São Paulo, 2003. http://www.teses.usp.br/teses/disponiveis/11/11136/tde-20052003-140139/.

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Foram avaliados dois modelos para estimativa do potencial produtivo relativo de cana-de-açúcar. Utilizou-se dados de produtividade (t.ha -1 ) de experimentos, dados de campo da Usina Santa Rita, localizado no município de Santa Rita do Passa Quatro e das áreas de cana-de-açúcar da Usina Costa Pinto em Piracicaba, todas localizadas no Estado de São Paulo, Brasil, para realizar uma comparação entre a produtividade obtida em campo e a produtividade relativa (% da máxima produtividade) estimada pelo modelo matemático. As variáveis de entrada são o fósforo (P, mmolc/kg), potássio (K, mmolc/kg), capacidade de troca de cátions (T, mmolc/kg), saturação por bases (V%) e o teor de argila (Arg%). As avaliações mostraram que o modelo estimou de forma eficiente a produtividade relativa de cana-de-açúcar, com relações altamente significativas (P<0,001) entre produtividade medida no campo e produtividade relativa estimada. Verificou-se que o modelo ganha precisão quando se trabalha em escalas maiores (dados experimentais) em comparação com escalas menores (grandes fazendas). Uma análise de regressão linear múltipla, pelo método stepwise, foi utilizada para verificar quais foram os fatores que influenciaram a produtividade da cana-de-açúcar nos diferentes anos. Verificou-se forte influencia do número de cortes e das variedades, entretanto notou-se que as variáveis do solo utilizados como variáveis de entrada (P,K,T,V,Arg) nem sempre influenciaram a produtividade nos diferentes anos. Constatou-se então que as ferramentas estatísticas podem ser limitadas para elaboração de modelos. Consequentemente o modelo mostrou-se uma ferramenta útil para identificação da capacidade produtiva de áreas para a cana-de-açúcar de maneira holística e integrada em comparação aos métodos estatísticos. O modelo foi aplicado, numa escala regional, no o município de Piracicaba. Através de um sistema de informações geográficas (SIG) foram gerados um mapa de declividade, mapa de distância em relação a 4 usinas da região e uma mapa de produtividade relativa. Os mapas foram úteis na identificação da distribuição espacial da cana-de-açúcar no município. Utilizou-se o modelo climático da FAO para simular a produtividade da cana-de-açúcar mês a mês durante um ano. O mesmo não apresentou correlação com a produtividade média mensal obtida. Este modelo foi concebido para estudos em dimensões continentais com regiões climaticamente contrastantes. Em escala local se mostrou muito sensível ao déficit hídrico para estimar a produtividade da cana-de-açúcar adequado para realizar estimativas, principalmente porque esta cultura é tolerante a períodos de stress hídricos.
Two models of sugarcane were evaluated. The yield (t/ha) out of experimental data, and from fields of the Santa Rita Sugar Mill, located at Santa Rita do Passa Quatro, and from large farms of the Costa Pinto Sugar Mill, located at Piracicaba, all in the State of São Paulo Brazil were compared to the estimated relative yield (% of the maximum yield) by a mathematical model having as input the soil fertility parameters: potassium content (K, in mol/kg), phosphorus content (P, in mol/kg), cation exchange capacity (T, in mol/kg), base saturation (V, in %) and clay content (Arg, in %), by linear regression. The high significance of the regressions (P<0,001) showed a closed relation between estimated and measured yield. The model gain precision with bigger scales (experimental data) compared to the smaller scales (larger farms). A linear multiple regression statistical analysis, by the stepwise method, were applied to select the soil parameter which most affected the yield. The ratton number and the sugarcane variety were the most important factors determining yield, overcoming the soil fertility parameters which not always affected yield according to this analysis. Consequently, the model was a better tool to identify soil capability for sugarcane yield, in a holistic and integrated manner, than the statistical analysis. The soil model to estimated relative yield were applied tin the regional scale on the Piracicaba county to generate maps of the distance of sugarcane field to the sugar mills, relative sugarcane yield of the fields, and land slopes of the sugarcane fields. The maps were useful to elucidate the sugarcane distribution within the county. An estimation of yield by the FAO model, using weather data as input parameters, showed a large month to month yield variation in discrepancy to the field observations. No significance regressions demonstrated that the yield estimated by FAO model is not related to the field data. This model was created for studies at continental level with contrasting weather differences, but is too sensitive for the water deficit to estimate sugarcane yield at local and regional scale, mainly because this crop is particularly tolerant do periodic water stress.

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Edler, Barbara [Verfasser], Johannes [Akademischer Betreuer] Isselstein, Bärbel [Akademischer Betreuer] Gerowitt und TIEDEMANN Andreas [Akademischer Betreuer] VON. „Weeds in a changing environment : Responses to altered temperature and soil water potential in four soil types and relative future habitat suitability for potential distribution of three range-expanding weed species in northwest Germany / Barbara Edler. Gutachter: Bärbel Gerowitt ; Andreas Von Tiedemann. Betreuer: Johannes Isselstein“. Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2015. http://d-nb.info/1069664871/34.

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Wu, Chu-Hua, und 吳朱華. „Suitability of Eutrophication Model on Water Reservoirs“. Thesis, 2006. http://ndltd.ncl.edu.tw/handle/40773219254109339712.

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碩士
國立成功大學
工學院工程管理專班
95
In general, the quality of the reservoir water is judged by the method of Eutrophication. However, Eutrophication is evaluated differently across previous studies. Taiwan, EPA (Environmental Protection Administration Executive Yuan, R.O.C.) adopts the Carson Trophic State Index (CTSI), which is one of the common methods of Eutrophication though many researchers are skeptical about it. This research aims to formulate the progress of the Eutrophication and predict the tendency of the Eutrophication by estimating the Eutrophication parameters.Data with Nanhua Reservoir on water quality (1992-2005) are analyzed in this study. Carson Trophic State Index and related parameters, such as Transparency, Total Phosphorus, Chlorophyll a, Dissolved Oxygen, Conductivity, Total Nitrogen, pH and Turbidity, are selected to estimate the Eutrophication formation model. Results of the study clearly showed Total Phosphorus, Chlorophyll a, Transparency, the three parameters chosen for the modeling and the Total Phosphorus was found to be the most important parameter for the modeling. The results are consistent with previous studies on the Nanhua Reservoir that these parameters are important in explaining and predicting the Eutrophication. A series of replications are conducted on Wushantou Reservoir, Renyitan Reservoir, Lantan Reservoir, and Chingmein Reservoir. The significant parameters for evaluation of Eutrophication are consistent with those utilized in the study of Nanhua Reservior except for those in Chingmein Reservoir. The reasons for such inconsistency should be explored in future research.

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Makofane, Rosina. „Evaluation of water hyacinth (Eichhornia crassipes) suitability as feedstock for biogas production“. Diss., 2018. http://hdl.handle.net/10500/25351.

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The suitability of water hyacinth in biogas production was evaluated as a means of waste management in the interests of sustainable energy production. Batch anaerobic digestion (AD) of water hyacinth was conducted to determine the optimal pre-treatment method for maximum methane production. Physical pre-treatment methods produced a highest cumulative methane of 2.3 L during batch AD. The selected pre-treatment method, hand-cutting, was further evaluated in a semi-continuous AD using both mono- and co-digestion. The emphasis was on identifying microbial communities involved and their response to organic loading rates (OLRs). The Illumina Miseq results proved that bacterial communities were more sensitive to disturbances caused by irregular OLRs as compared to archaeal communities. In addition, the variation in substrate nutrients as a result of mono- and co-digestion of water hyacinth, contributed to variations in the bacterial diversity. For example, Bacteroides and Petrimonas diversity varied between mono- and co-digestion. Overall, the study verified that water hyacinth is a suitable feedstock for biogas production and the simple pre-treatment methods are recommended. Furthermore, OLRs influenced the microbial community structure and associated biogas yield.
National Research Foundation (South Africa)
Environmental Science
M. Sc. (Environmental Science)

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Lin, Wen-Chi, und 林文麒. „Suitability and Cost of Nanofiltration Membrane Process in Drinking Water Treatment Plants in Taiwan“. Thesis, 2002. http://ndltd.ncl.edu.tw/handle/17826857194390826467.

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碩士
國立交通大學
環境工程所
90
As the levels of drinking water regulation is getting more and more stringent, the update of drinking water treatment plants in Taiwan is becoming necessary. This study focus on NF membrane treatment process applied in drinking water treatment plants in Taiwan. We investigate raw drinking water quality in small or middle-sized drinking water treatment plants in Taiwan and bring up some suggestion that about suitable membrane treatment raw water quality information. Furthermore, we apply previous investigation and use membrane treatment plant design software to estimate that NF membrane treatment plant’s capital cost and Q&M cost. Analysing LSI variation for drinking water treatment plants in Taiwan showed that these raw water in drinking water treatment plants in the northern Taiwan region have corrodible tendency and are suitable for NF membrane treatment raw water, but those raw water in drinking water treatment plants in the Southern Taiwan region are easy to deposit CaCO3 and must to step up additional chemical-pretreatment equipment. because these raw water in drinking water treatment plants in the North Taiwan region and those raw water in several special plants in the South Taiwan region that have high turbidity; they need higher physical-pretreatment cost. these raw water in drinking water treatment plants in South Taiwan region and those raw water in several special plants in East Taiwan region that have high LSI value, so they need higher chemical-pretreatment cost. A full-scale NF membrane treatment plant usually contains suitable pretreatment segment, chemical cleaning membrane element segment, and concentrate disposal segment. According to water quality in HSINCHU area, we suggest that suitable mix ratio＝4(filtrate and permeate), recovery＝85%(permeate), and the reasonable cost per m3 product water for 5000 m3,12500 m3 and 2500 m3 NF membrane plant is 5.11, 3.99 and 3.78 dollars/m3 respectively. When the mix ratio is more than 4, the total unit water treatment cost (NF treatment cost and conventional treatment cost) are approximately 15 dollars/m3. Conventional treatment process combined with NF membrane treatment process is a suitable and low cost advanced treatment process for drinking water treatment. According to cost-benefit for NF membrane, the result showed that building NF membrane plant in the northern Taiwan region or eastern Taiwan region is higher cost-benefit, but building NF membrane plant in the southern Taiwan region or midst Taiwan region is lower cost-benefit.

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Schabort, Cornelis Johannes. „Evaluation of suitability of water hyacinth as feedstock for bio-energy production / Cornelis JohannesJ. Schabort“. Thesis, 2014. http://hdl.handle.net/10394/11969.

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The suitability of water hyacinth (Eichornia crassipes) as a viable feedstock for renewable energy production was investigated in this project. Water hyacinth used in this study was harvested from the Vaal River near Parys in the northwest region of the Free State province, South Africa (26°54′S 27°27′E). The wet plants were processed in the laboratory at the North-West University by separating the roots from the leaves and the stems, thus obtaining two separate water hyacinth feedstock. Characterisation of the feedstock showed that the stems and leaves are more suitable for bio-energy production than roots, due to the higher cellulose and hemicellulose content and very low lignin content of the stems and leaves. Water hyacinth was evaluated as feedstock for the production of bio-ethanol gel, bio-ethanol, bio-oil and bio-char. The recovery of water from the wet plants for use in bio-refining or for use as drip-irrigation in agriculture was also investigated. Cellulose was extracted from water hyacinth feedstock to be used as a gelling agent for the production of ethanol-gel fuel. A yield of 200 g cellulose/kg dry feedstock was obtained. The extracted cellulose was used to produce ethanol-gel with varying water content. The gel with properties closest to the SANS 448 standard contained 90 vol% ethanol and 10 vol% water, with 38 wt% cellulose. This gel was found to ignite readily and burn steadily, without flaring, sudden deflagrations, sparking, splitting, popping, dripping or exploding from ignition until it had burned to extinction, as required by SANS 448. The only specifications that could not be met were the viscosity (23,548 cP) and the high waste residue (32 wt%) left after burning. The other major concern is the extremely high costs involved with the manufacturing of ethanol-gel from water hyacinth cellulose. It can be concluded that ethanol-gel cannot be economically produced using water hyacinth as feedstock. Chemical and enzymatic extraction of water from the feedstock, which is stems and leaves or roots, showed that the highest yield of water was obtained using a combination of Celluclast 1.5 L, Pectinex Ultra SP-L and additional de-ionised water. A yield of 0.89 ± 0.01 gwater/gwater in biomass was realised. This is, however, only 0.86 wt% higher than the highest yield obtained (0.87 ± 0.01 gwater/gwater in biomass) using only Pectinex Ultra SP-L and de-ionised water. It is recommended to use only Pectinex Ultra SP-L and de-ionised water at a pH of 3.5 and a temperature of 40°C. Using one enzyme instead of two reduces operating costs and simplifies the chemical extraction process. The extracted water, both filtered and unfiltered, was not found to be suitable for domestic use without further purification to reduce the total dissolved solids (TDS), potassium and manganese levels. Both the unfiltered and filtered water were, however, found to be suitable for industrial and agricultural purposes, except for the high TDS levels. If the TDS and suspended particle level can be reduced, the extracted water would be suitable for domestic, industrial and agricultural use. The potential fermentation of the sugars derived from the water hyacinth, using ultrasonic pretreatment, was investigated. Indirect ultrasonic treatment (ultrasonic bath) proved to be a better pretreatment method than direct sonication (ultrasonic probe). The optimum sugar yield for the ultrasonic bath pretreatment with 5% NaOH was found to be 0.15 g sugar/g biomass (0.47 g sugar/g available sugar) using an indirect sonication energy input of 27 kJ/g biomass. The optimum sugar yield is lower than those reported in other studies using different pretreatment methods. Theoretically a maximum of 0.24 g ethanol can be obtained per g available sugar. This relates to an ethanol yield of 0.08 g ethanol/kg wet biomass. The low yield implies that ethanol production from water hyacinth is not economically feasible. The production of bio-oil and bio-char from water hyacinth through thermochemical liquefaction of wet hyacinth feedstock was investigated. An optimum bio-char yield of 0.55 g bio-char/g biomass was achieved using an inert atmosphere (nitrogen) at 260°C and the stems and leaves as feedstock. With the roots as feedstock a slightly lower optimum yield of 0.45 g bio-char/g biomass was found using a non-reducing atmosphere (carbon monoxide) at 280°C. The bio-oil yield was too low to accurately quantify. As water is required during thermochemical liquefaction, it was found unnecessary to dry the biomass to the same extent as was the case with the pretreatment and fermentation of the water hyacinth, making this a more feasible route for biofuel production. Bio-char produced through liquefaction of roots as the feedstock and leaves and stems as the other feedstock had a higher heating value (HHV) of 10.89 ± 0.45 MJ/kg and 23.31 ± 0.45 MJ/kg respectively. Liquefaction of water hyacinth biomass increased the HHV of the feedstock to a value comparable to that of low grade coal. This implies a possible use of water hyacinth for co-gasification. The most effective route for bio-energy production in the case of water hyacinth was found to be thermochemical liquefaction (12.8 MJ/kg wet biomass). Due to the high production costs involved, it is recommended to only use water hyacinth as a feedstock for biofuel production if no alternative feedstock are available.
MIng (Chemical Engineering), North-West University, Potchefstroom Campus, 2014

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Chiang, Yeh-Hsiu, und 姜燁秀. „From the Soil and Water Conservation Law View to Investigate the Suitability of Slpoe Land Utilization Supervision“. Thesis, 2016. http://ndltd.ncl.edu.tw/handle/01637014042688230309.

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博士
國立中興大學
水土保持學系所
104
Land Development Supervision System in Taiwan according to their control measures can be divided into two categories. The first category for the Development Permit, which refers to all types of land development and utilization plan shall be in accordance with the regional law, urban planning law and the National Parks Act delineated, compiled and the use of prescribed use zoning classification. The second category refers to the land of the operator. The user or owner to a specific area (such as slopelands, reservoirs, water quality, watershed and other protected areas) before development, should be in accordance with soil and water conservation law or the relevant provisions of the environmental impact assessment law. Implementation and maintenance of soil and water conservation process or environmental impact assessment and other supporting measures should be applied. Current land development supervised system has been in operation for many years, However, after the 921 earthquake, the loose earth and rock hillside, coincides with climate change, high intensity and long duration of the extreme rainfall caused collapse, the ground slippery, landslides and other disasters. Increasing earth and sand disasters resulted in the current system has been unable to respond to all kinds of complex disasters. All people have asked the Central government should review land development and utilization control system. Therefore, since the 2009 typhoon Morakot, the Executive Yuan posted the space program, introduced the concept of environmentally sensitive areas, set up land planning Act and gradually, in order to avoid over-exploitation of land. But environmentally sensitive areas of the system refers to a specific area delineated different activity authority, and without compensation planning and related supporting measures, resulting in competing legal issues. Land Planning Act promulgated on May 1, 2016. Regional Planning Act will cease to apply, in order to avoid the recurrence of the problems in the current system. This research focused in the view of Soil and Water Conservation Law, checked each term of development control laws and regulations and relevant designated environmentally sensitive areas of the set principles. The misplace and scale for limiting the development of land use planning were also discussed. The doubtful points of land restoration area and compensation system of were pinpointed. The differences in the development permit and licensing system were compared. The conduct public information and citizen participation in the public relations were analyzed. The following recommendations were suggested in order to provide the reference for the competent authorities of the Land Planning Act 1. Re-investigate environmentally sensitive areas under the view of Soil and water conservation law. 2. Establish a hierarchical control system of environmentally sensitive areas 3. Use of diversified indemnity policy. 4. Integrate the special public class system of different regulations. 5. Strengthen public participation mechanisms.

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Lin, You-Tze, und 林佑澤. „Applying multiple criteria decision making method to assess the suitability of water quality monitoring stations－A case study of the Taipei Water Resource Domain“. Thesis, 2012. http://ndltd.ncl.edu.tw/handle/96249948755011256903.

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碩士
逢甲大學
水利工程與資源保育研究所
100
Water resource management is a very important issue nowadays. Due to economic and industrial development, water quality risk increase the complexity of water resource management. Environmental monitoring records can help us understand the variability of environmental properties. For example, water quality monitoring records provide important information which helps people understand water quality if it is below standard or if it needs improvement through management strategies. However, water quality monitoring networks have traditionally been designed on the basis of experience and intuition in keeping with increased management needs related to preventing water quality deterioration, rather than being based on a systematic design and specified monitoring objectives. In many developing countries, most of the existing monitoring networks exhibit deficiencies in terms of providing information required for integrated watershed management. The objective of this study was to discuss the suitability of the water quality station network in the Taipei Water Specific Area. In this study, we used a simple additive weighting system, VIKOR and entropy weight method to evaluate a single and multiple indicator system suitability. We explored the differences of the different indicators project and the results of the different analytical methods for water quality monitoring stations. A Single index using Geographic Information Systems to assess the influence of different land uses with buffer analysis. When an area is highly influenced by land use activities, the water quality in this area has a higher pollution risk and needs monitoring. We developed a Multi-indicator system in an attempt to establish the validity. This development comprehensive assessment factored in seven indications: agriculture, community, non-point source pollution, landslides, hillsides overrun by excessive land use, green cover, water quality measurement stations. This study therefore addressed the suggestion that it is three water quality monitoring stations in the Bei-Shih Creek Basin, and two water quality monitoring stations in the Sin-Dian Creek Basin, Water quality monitoring stations to sort the address set the lowest in sub-catchment in the Nan-Shih Creek Basin.

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Carlström, Karolina, und Elin Renstål. „Characteristics of managed and unmanaged water bodies influencing their suitability as mosquito breeding habitats in Bahir Dar, Ethiopia“. Thesis, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-226165.

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Mosquito-borne diseases like malaria, dengue fever, yellow fever and West Nile virus are serious problems in many parts of the world, especially in Africa, and partially in Ethiopia. Millions of people become infected and several hundred thousand people die worldwide from these diseases every year. The most conventional methods for mosquito vector control target female adult mosquitoes in a reactive way using insecticides. However, it is possible to perform proactive vector control through source reduction. The main focus of this study was to investigate if there are any associations between characteristics of managed still water bodies and the presence of mosquito larvae in Bahir Dar, Ethiopia. This was done by measuring twelve variables, both abiotic and biotic; pH, conductivity, dissolved oxygen, turbidity, biochemical oxygen demand, nitrate, phosphate, sulphate, carbonate, depth and presence of algae as well as collecting and counting mosquito larvae in ten different sites, during a time series of five weeks. The most common managed waters believed to serve as efficient breeding habitat for mosquitoes were ponds and ditches used for irrigation, drainage or cultivation. A total of 204 mosquito larvae were collected, where 95% were found in four of the ten sites, three of them were managed waters and the last one was unmanaged. Statistical analyses were performed in order to examine potential correlations and differences among the sites. Wilcoxon test was performed to investigate differences between managed and unmanaged waters. Simple linear regression analyses were performed to identify driving variables for the presence of mosquito larvae. The main results from the group tests were significant differences in mosquito larvae density between managed and unmanaged sites. Significant differences between mosquito sites and zero-sites for dissolved oxygen and sulphate were found. Simple linear regression revealed pH and dissolved oxygen as driving variables for mosquito larvae presence. It was concluded that resources should be put on treatment or manipulation of ponds, which were considered the preferred mosquito breeding habitats. However, if conflicts arise among interests concerning food production, measures must be planned and performed thoughtfully or focus should be put on less controversial breeding habitats. Among the driving variables, dissolved oxygen was the suggested variable to manipulate in order to reduce mosquito larvae populations.
Myggburna sjukdomar som malaria, denguefeber, gula febern och West Nile viruset orsakar allvarliga problem i många delar av världen, särskilt i Afrika, och till viss del Etiopien. Miljontals människor världen över blir smittade och flera hundratusen dör varje år till följd av dessa sjukdomar. De konventionella metoderna för att kontrollera och minska spridningen av myggburna sjukdomar handlar om att kontrollera vuxna myggor med insektsmedel. Det är dock möjligt att utföra en mer förebyggande vektorkontroll genom att minska populationen. Fokus för denna studie var att undersöka om det fanns några samband mellan mygglarvsförekomst och egenskaperna hos mänskligt reglerade eller oreglerade vatten i och kring Bahir Dar i Etiopien. Detta gjordes genom att mäta tolv variabler, både abiotiska och biotiska såsom; pH, konduktivitet, löst syre, turbiditet, biokemisk syreförbrukning, nitrat, fosfat, sulfat, karbonat, djup och algförekomst, samtidigt som mygglarver samlades in och räknades, vilket utfördes på tio olika platser under fem veckor. Den vanligaste typen av reglerade vatten som potentiellt skulle kunna utgöra effektiva mygglarvshabitat ansågs vara dammar och diken som används för bevattning, dränering eller odling. Totalt samlades 204 mygglarver in och 95 % av dem fanns i enbart fyra av de tio etablerade mätplatserna, där tre var reglerade och den sista var oreglerad. Statistiska analyser utfördes för att undersöka potentiella samband och skillnader i mygglarvsförekomst och uppmätta variabler bland de tio mätplatserna. Wilcoxons metod användes för att undersöka om det fanns skillnader mellan reglerade och oreglerade ytvattensamlingars larvförekomst och egenskaper. Enkel linjär regressionsanalys utfördes för att hitta eventuella drivvariabler som därmed anses styra mygglarvsförekomsten. De huvudsakliga resultaten i studien var att det förekom en signifikant skillnad i mygglarvsdensitet mellan reglerade och oreglerade ytvattensamlingar. Signifikanta skillnader i löst syre och sulfat förekom även mellan myggsiter och nollsiter. Enkel linjär regression visade på att pH och löst syre var de mest drivande variablerna för mygglarvsförekomsten i denna studie. Slutsatsen var att dammar utgjorde de mest tilltalande habitaten i samband med mygghonors äggläggning och därför borde prioriteras med avseende på resursfördelning vid planering och utförande av vektorkontroll. Om det skulle uppstå konflikter mellan olika intressen som kan äventyra matproduktionen bör insatser planeras och genomföras med försiktighet eller istället göras i andra mindre kontroversiella mygglarvshabitat. Den drivvariabel som ansågs vara den mest lämpliga att manipulera var löst syre.

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Wutor, V. C., C. A. Togo und B. I. Pletschke. „Suitability of total coliform beta-D-galactosidase activity and CFU counts in monitoring faecal contamination of environmental water samples“. 2009. http://hdl.handle.net/10962/d1006165.

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Total coliforms are a group of bacteria found in high numbers in mammalian intestines; hence their presence in water indicates the possible contamination with faecal material. Total and faecal coliform counts were monitored over a period of 18 months using mFC, m-Endo and CM1046 media together with enzymatic assays on 215 environmental water samples obtained from the Eastern Cape Province of South Africa. A positive correlation, with an R2 value of 0.9393 was observed between faecal and total coliform colony units employing mFc and m-Endo media, and 0.8818 using CM1046 media. Also, a positive correlation was observed between Escherichia coli colony-forming units and β-D-galactosidase (B-GAL) activity (R2=0.8542). Overall, this study indicated that faecal contamination of environmental water samples could be monitored by measuring total coliform β-galactosidase activity and total coliform colony-forming units.

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Stück, Heidrun Louise. „Dimensional Sandstones: Weathering Phenomena, Technical Properties and Numerical Modeling of Water Migration“. Thesis, 2013. http://hdl.handle.net/11858/00-1735-0000-0020-E940-B.

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Ruben, Aza-Gnandji Cocou Davis. „Salinity of irrigation water in the Philippi farming area of the cape flats, Cape Town, South Africa“. Thesis, 2011. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_8633_1365586459.

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This research investigated the nature, source and the spatial variation of the salinity of the water used for irrigation in the urban farming area of Philippi, which lies in the Cape Flats region of the Cape Town Metropolitan Area, South Africa. The irrigation water is mainly drawn from the Cape Flats aquifer, and pumped into ponds for eventual crop irrigation. Water samples were collected in summer and in winter from fifteen selected sites using standard water sampling procedures. Each site consisted of one borehole and one pond. The samples were routinely analyzed for salinity levels, and concentrations of major and minor ions. From the same boreholes and ponds, water was sampled in summer for isotope analysis to assess effects of evaporation on the water quality and salinity. Descriptive statistics were used to display the variation in range of specific ions in order to compare them with the recommended ranges. Geographical Information Systems analysis described the spatial distribution of the salinity across the study area, and hydrogeochemical analysis characterized the various waters and detected similarities between the water samples in the study area and other waters found in the Cape Flats region. In addition, the US salinity diagram classification of irrigation water developed by Richards (1954) was used to assess the current suitability of groundwater and pond water samples collected during the entire sampling period for irrigation activities. The research indicated that the concentrations of some ions such as chloride, nitrate, potassium and sodium exceeded in places in the study area, the target range values set by the Department of Water Affairs and Forestry (DWAF, 1996) and the Food and Agriculture Organization (Ayers and Westcot, 1985). It revealed that borehole and pond water were mostly brackish across the area regarding their total dissolved salts content, and fresh water was only found in the middle part of the study area. The research found that sea water does not intrude into the aquifer of the study area, and the accumulation of salts in groundwater and soil in the study area is mainly due to the agricultural activities and partially due to the natural movement of water through the geological formation of the Cape Flats region. The conceptual model of the occurrence of the salinization process supported these findings. From this investigation it is understood that the groundwater and pond water in the study area were generally suitable for irrigation purposes but they have to be used with caution as the vegetables are classified as sensitive and moderately sensitive to salt according to DWAF Irrigation water guidelines (1996). The quality of these waters was mainly affected by the land use activities.

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Sun, Chin-Chin, und 孫錦進. „Suitability of Teaching Materials Related toSoil and Water Resources in the Textbooks of Current Grade 3-9 Curriculum Using Content Analysis“. Thesis, 2014. http://ndltd.ncl.edu.tw/handle/03857957943783615614.

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碩士
國立中興大學
水土保持學系所
102
Textbooks are the main education material for student learning. It is a convenient and direct way to learn the concepts of soil and water resources from textbooks. Therefore, the content of the textbooks would influence greatly the student’s learning attitudes and outcomes. The textbooks of Science & Technology and Social Study published by the Nani, Knsh and Han-Lin companies for the grade-third to -ninth students were adopted as materials in this study. The content and/or page proportion of soil and water conservation concepts to the whole stuffs were reviewed by content analysis method in this study for the reference of textbook revision and purchasing. According to the statistics of page proportion related to soil and water conservation,the Knsh and the Han-Lin version show the highest page proportion of soil and water conservation concepts in the textbooks of Science & Technology and/or Social Study, which are 13.4% and 6.22%, respectively. The current contents of teaching materials shows that the concepts of water characteristics are mainly emphasized on the field of Science & Technology, while the Social Study are usually focusing on human activities such as: “water pollution and control” and “effects of human activities on the environment”. However, soil resources are seldom emphasized on both of the two fields. Finally the problems of duplication contents and out of scopes are found in several versions,which should be revised properly. In addition, the topics related to debris flow and forest management are examined, and different views of point are also recommended in this study for the references of teachers and publishing companies.

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Abdulai, Issaka. „Productivity, water use and climate resilience of alternative cocoa cultivation systems“. Doctoral thesis, 2018. http://hdl.handle.net/11858/00-1735-0000-002E-E3F3-9.

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Chao, Kuo-Kuang, und 趙國光. „Suitability of Escherichia coli and Total Coliforms and Their Enumerating Methods in the Assessment of Fecal Pollution of Subtropical Fresh Water Environments“. Thesis, 2003. http://ndltd.ncl.edu.tw/handle/91868678184869456654.

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碩士
東吳大學
微生物學系
91
In the present study, we have used standard methods published by the Environmental Protection Agency, Republic of China to monitor the numbers of total bacteria, Escherichia coli, coliforms, fecal coliforms, Enterococcus and Aeromonas sp. in the raw surface and underground freshwater, and to evaluate the relationships between these microorganisms. Two rapid microbial identification systems (i.e., MIDI and API 20E) were used to evaluate the accuracy of the Colilert-18® and m-TEC membrane filtration method。A total of 125 water samples were taken from 24 sampling sites throughout the northern and central parts of Taiwan. Of all these sites, 14 are from the regular water treatment plants and 10 are from the primitive water supply systems. The results indicate that the number of total bacteria in water samples collected from regular water treatment plants is significantly higher than primitive water supply systems. Significant positive relationships between total bacteria counts and Escherichia coli, coliforms, Enterococcus, Fecal coliforms and Aeromonas sp. are observed in water samples from regular treatment plants, but not in the primitive water supply systems. Enterococcus can be found in all the water samples, and show positive relationships with coliforms and E. coli in samples from the primitive water supply systems. Therefore, we believe Enterococcus may have the potential to replace coliforms as a good water quality indicates in the primitive water supply systems. The official membrane filtration method for fecal coliforms enumeration involved the usage of m-FC medium. However, in the present study, we have clearly shown that this medium does not function as well as it does in the temperate region. We believe that high temperature and poor water quality cause too many heat resistant bacteria and high total bacterial counts in these water samples. If the differential ability of the selective medium is not powerful enough, these medium then could not allow the correct target microorganisms to grow out which results many interferences. At present, two alternative methods for E. coli enumeration have been published by the Environmental Protection Agency, and they are the m-TEC membrane filtration method and the Colilert test which uses the Defined Substrate Technology® to simultaneously detect total coliforms and E. coli in water samples. In this study, the accuracy of m-TEC method and colilert are evaluated using MIDI and API 20E rapid microbial identification system. According to our results, in E. coli positive samples, the accuracy of m-TEC method is 90% according to MIDI and API 20E, respectively, and in the E. coli negative samples, they are 99% accurate, respectively. As for the Colilert test, in E. coli positive samples, the accuracy is 93% and 97% in the E. coli negative samples. When using Colilert test to detect coliforms in water samples, 100% accuracy in all coliform-positive wells were confirmed, and the false negative result is about 7%. Based on these observations, we believe that using Colilert-18 to evaluate the number of coliforms and E. coli in sub-tropical freshwater can provide us with safety information due to its low false-positive and false-negative results.

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Vaz, Leandro Alves. „Optimization of estuarine aquaculture exploitation: modelling approach“. Doctoral thesis, 2020. http://hdl.handle.net/10773/30411.

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Aquaculture is one of the fastest growing activities worldwide. In 2006, it already accounted for around 40% of total fish consumption, and since 2012, aquaculture is the main source of marine food supplies. However, this strong and fast development of the sector tends to be reflected in significant environmental impacts and new challenges in the management and planning of the coastal areas. In this context, this work intends to contribute to the sustainability of the sector, by identifying preferential locations to ensure aquaculture expansion and proper operation in a sustainable manner and with minimal environmental impact under optimal hydrodynamic and water quality conditions in Ria de Aveiro (Portugal) and Rias Baixas (Spain). This study is particularly relevant because the mapping of the most suitable areas for aquaculture exploitation has never been performed in any of the study areas, proving to be crucial, not only to demonstrate the potential in this commercial activity and to encourage investment by companies, but mainly to enable an adequate targeting of investments. To achieve this objective, a multidisciplinary methodology was applied, which comprised the following steps: 1 - characterization of hydrodynamic, physical, chemical and biological variables governing aquaculture activities; 2 - implementation, calibration, validation and exploitation of hydrodynamic and water quality models; 3 - development of a habitat model integrating the numerical model results into an exploitation index; 4 - application of a habitat model and mapping of the suitable and unsuitable areas for fish and shellfish exploitation in Ria de Aveiro and Rias Baixas. The results show that 22% of Ria de Aveiro is suitable for fish production (axis of the main channels, from the inlet to the middle of the channels), while the production of pelagic fish in the Rias Baixas is not recommended due to vertical gradients of water temperature and dissolved oxygen. Concerning to bivalves, the habitat model predicts that 31% of Ria de Aveiro is suitable for production. In the Rias Baixas, except for some marginal areas and upstream areas, the suitability for bivalve production is almost complete, confirming the high exploitation of the region. The definition of suitable areas for aquaculture exploitation is highly related with the different geomorphological, hydrological and biogeochemical processes of Ria de Aveiro and Rias Baixas, but also with the vertical structure of the estuarine systems: homogeneous water column (Ria de Aveiro) in opposition to a partially mixed estuarine system (Rias Baixas). Results of Ria de Aveiro indicate that the upstream areas of the lagoon are the most vulnerable from the water quality point of view, highlighting the importance of the advective processes in the lagoon’s water quality, in opposition to Rias Baixas dynamics, where stratification is more relevant. In Rias Baixas, the strong vertical gradient of water temperature and dissolved oxygen disallows fish from having sustainable growth rates. The numerical modelling approach combined with a habitat model allowed to consider a large number of variables, integrating them in order to generate results that are very useful for coastal managers and investors. Therefore, this work shows that the methodology developed here is effective for the identification of favorable areas for the exploitation of species with economic interest, generating a tool that can be replicated and/or adapted in future studies in other coastal systems. Finally, this work demonstrated the potential of hydrodynamic and biogeochemical modelling to support the decision making process in future coastal plans.
A aquacultura é uma das atividades económicas com maior taxa de crescimento. Em 2006, já era responsável por cerca de 40% do consumo total de peixe, e em 2012, consolidou-se como a principal fonte de alimentos de origem marinha. Contudo, este forte e rápido desenvolvimento do setor tende a refletir-se em significativos impactos ambientais, e em novos desafios na gestão e planeamento das zonas costeiras. Neste contexto, este trabalho pretende contribuir para a sustentabilidade do sector, identificando locais preferenciais para a exploração aquícola de forma sustentável, com um impacto ambiental mínimo e um custo relativamente baixo, sob condições ideais de hidrodinâmica e qualidade da água na Ria de Aveiro (Portugal) e Rias Baixas (Espanha), os dois sistemas com maior exploração no NW da Península Ibérica. Este estudo torna-se particularmente relevante porque o mapeamento das localizações mais adequadas à exploração aquícola nunca foi efetuado em nenhuma das áreas de estudo, revelando-se fulcral, não só para demonstrar o potencial da atividade comercial e incentivar o investimento das empresas, mas principalmente para permitir um direcionamento adequado dos investimentos, e contribuir para a sustentabilidade do setor. Para alcançar este objetivo foi aplicada uma metodologia multidisciplinar que compreendeu a realização dos seguintes passos: 1 - caracterização das variáveis hidrodinâmicas, físicas, químicas e biológicas importantes para a aquacultura; 2 - implementação, calibração, validação e aplicação de modelos hidrodinâmicos e de qualidade da água; 3 - desenvolvimento de um modelo de habitat, para transformação dos resultados dos modelos numéricos, num índice de exploração; 4 - aplicação do modelo de habitat, e mapeamento das zonas mais adequados à exploração de peixes e bivalves na Ria de Aveiro e Rias Baixas. Os resultados evidenciam que 22% da Ria de Aveiro é adequada para a produção de peixes (eixo dos principais canais, desde a embocadura até à zona intermédia dos canais), enquanto que a produção de peixes pelágicos nas Rias Baixas não é aconselhável, devido aos gradientes verticais de temperatura da água e de oxigénio dissolvido. Relativamente aos bivalves, o modelo de habitat prevê que 31% da Ria de Aveiro é adequada à sua produção. Nas Rias Baixas, exceptuando algumas zonas marginais e perto das cabeceiras, a adequabilidade para a produção de bivalves é quase total, confirmando a elevada exploração que se verifica na região. A definição das áreas propícias para a exploração aquícola está altamente relacionada com os diferentes processos geomorfológicos, hidrológicos e biogeoquímicos que ocorrem na Ria de Aveiro e nas Rias Baixas, mas também com a estrutura vertical dos sistemas estuarinos: uma coluna de água homogénea (Ria de Aveiro) em oposição a um sistema estuarino parcialmente estratificado (Rias Baixas). Os resultados para a Ria de Aveiro indicam que as cabeceiras dos principais canais são as áreas mais vulneráveis do ponto de vista da qualidade da água, evidenciando a importância da adveção nos processos ecológicos, em oposição à dinâmica das Rias Baixas, onde a estratificação adquire maior relevância. Nestes estuários, o forte gradiente vertical da temperatura da água e do oxigénio dissolvido impede que os peixes possuam taxas de crescimento sustentáveis. A abordagem de modelação numérica combinada com um modelo de habitat permitiu considerar um elevado número de variáveis, integrando-as de forma a gerar resultados de grande utilidade para gestores e investidores do setor aquícola. Consequentemente, este trabalho mostra que a metodologia aqui desenvolvida é eficaz para a identificação de locais propícios para a exploração de espécies de interesse económico, gerando uma ferramenta que pode ser replicada e/ou adaptada em estudos futuros a realizar noutros sistemas costeiros. Finalmente, este trabalho demonstrou o potencial da modelação hidrodinâmica e biogeoquímica no suporte ao processo de tomada de decisão em futuros planos de ordenamento das zonas costeiras.
Programa Doutoral em Ciência, Tecnologia e Gestão do Mar

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Schlüter, Maja. „Development of an integrated GIS-based simulation tool to support ecologically sound water management in the Amudarya river delta“. Doctoral thesis, 2003. https://repositorium.ub.uni-osnabrueck.de/handle/urn:nbn:de:gbv:700-2003110314.

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Extensive use of the Amudarya river waters for irrigation has severely impacted semi-natural ecosystems along its course and in its delta region. Currently, new strategies are searched for multi-user and multi-objective water management to mitigate ecological and socio-economic deterioration. The GIS-based modeling framework, TUGAI, has been developed to support exploration of alternative water management strategies for the Amudarya river delta and to analyze their ecological implications. Available information of heterogeneous type and quality on resource availability and habitat demands of deltaic ecosystems has been integrated into a comprehensive tool by a hybrid approach. A multi-objective water allocation model, AmuEPIC, has been combined with simple, spatially-explicit statistical and rule-based models of landscape dynamics, AmuGIS, and an ecological assessment procedure based on a fuzzy habitat suitability index model for riverine Tugai forests, TugaiHSI. Users can develop scenarios of alternative water management strategies for a time period of up to 30 years and compare their ecological effects. The tool facilitates a first quick assessment of the response of the delta environment to water management measures in a problem-oriented way. It assists in structuring the problem of water allocation to the environment, facilitates analysis of tradeoffs and uncertainties, fosters discussion between stakeholders and supports a goal finding process. Results of scenario analysis demonstrate solutions to given management tasks, which can serve as goals for implementation of measures in reality. First testing results indicate that there is a potential for increase of water discharge for environmental needs, while, at the same time, providing irrigation and other water users with sufficient water.

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Huang, Hsuan-Chang, und 黃炫璋. „The habitat suitability indices of environment for loliginid fishery in the Northeastern Waters of Taiwan“. Thesis, 2009. http://ndltd.ncl.edu.tw/handle/54178306559761623342.

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碩士
國立臺灣海洋大學
環境生物與漁業科學學系
97
Abstract In this study, we collected the fishing data in 2003~2007 from sampling fishermen operate in the northeastern waters of Taiwan, Sea surface temperature (SST), Sea surface salinity (SSS), and Sea level high (SLH). Based on this data, we carried out the habitat suitability index (HSI) to analyse the suitability indices of the fishing ground for loliginid fishery in the northeastern waters of Taiwan. The results of the suitability index (SI) showed SST in 23.9~29.5℃, SSS in 33.43~34.50psu, and SLH in 0.29~0.62m were more suitable for the fishing ground of loliginid fishery in the northeastern waters of Taiwan. The HSI showed that cumulate ratio of HSI-CI were increase when the HSI approach to 1, but HSI-Effort were not. Thus, the HSI-CI was more suitable for the suitability indices of the fishing ground of loliginid fishery in the northeastern waters of Taiwan than HSI-Effort. In additional, the spatial distribution with HSI-CI and CI showed the best fishing ground of loliginid fishery in the northeastern waters of Taiwan was between 25°~28.5°N and 121.5°~125.5°E. Keywords: Loliginid fishery, Sea surface temperature, Sea surface salinity, Sea level high, Habitat suitability index, Northeastern waters of Taiwan

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