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Lopes, Vicente Lucio 1952. "A numerical model of watershed erosion and sediment yield". Diss., The University of Arizona, 1987. http://hdl.handle.net/10150/191125.
Pełny tekst źródłaZheng, Tingting. "Mathematical modeling of soil erosion by rainfall and shallow overland flow". Thesis, Loughborough University, 2011. https://dspace.lboro.ac.uk/2134/9144.
Pełny tekst źródłaBarchyn, Thomas Edward, i University of Lethbridge Faculty of Arts and Science. "Field-based aeolian sediment transport threshold measurement : sensors, calculation methods, and standards as a strategy for improving inter-study comparison". Thesis, Lethbridge, Alta. : University of Lethbridge, Dept. of Geography, 2010, 2010. http://hdl.handle.net/10133/2616.
Pełny tekst źródłaxi, 108 leaves : ill. ; 29 cm
Navarro, Hernan Ricardo. "Flume Measurements of Erosion Characterstics of Soil at Bridge Foundations in Georgia". Thesis, Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/7267.
Pełny tekst źródłaSegarra, Eduardo. "A dynamic analysis of the crop productivity impacts of soil erosion: an application to the Piedmont area of Virginia". Diss., Virginia Polytechnic Institute and State University, 1986. http://hdl.handle.net/10919/51930.
Pełny tekst źródłaPh. D.
Mengler, Faron. "Gully erosion on rehabilitated bauxite mines". University of Western Australia. School of Earth and Geographical Sciences, 2008. http://theses.library.uwa.edu.au/adt-WU2008.0176.
Pełny tekst źródłaCox, Christopher 1967. "Watershed master planning for St. Lucia using geographic information systems". Thesis, McGill University, 1997. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=27303.
Pełny tekst źródłaCastro, Luciana Gomes. "Dinâmica da água em terraços de infiltração". Universidade de São Paulo, 2001. http://www.teses.usp.br/teses/disponiveis/11/11140/tde-26062002-145103/.
Pełny tekst źródłaTerracing is a soil conservation practice that aims to reduce water and soil loss by interception of runoff that occurs when rainfall intensities exceed infiltration capacity. Actually, dimensions of terraces are being determined in an empirical way; however, a more detailed understanding of the physics behind the hydrological functions of terraces would allow an optimized dimensioning of terraces. In this study the infiltration capacity of a level terrace was evaluated by the methods of flux density and water storage, under different management conditions (bare soil, pasture, conventionally tilled maize and zero-tillage maize) on an oxisol with a slope of 0.08 m m-1. In each treatment TDR sensors were installed at three observation points in the middle of the terrace canal (distance between points: 4 m; considered to be repetitions) at the depths of 0.05, 0.10, 0.20, 0.40, 0.60 and 0.80 m. At the same depths, undisturbed soil samples were taken to determine soil density and soil water retention curve. TDR readings were made automatically and a rainfall gauge automatically monitored rainfall intensity. At the end of each rainfall event, soil deposition was measured at 14 locations in the terrace canal in each treatment. During the dry season (July-August), unsaturated hydraulic conductivity was determined at each repetition at the same depths by the instantaneous profile method. The results showed that agricultural management influenced water and soil deposition in the terrace canal and these affected surfaced sealing and infiltration capacity. It was concluded that the high variation usually obtained between repetitions of the hydraulic conductivity determinations makes the detection of small differences between flux densities difficult. Therefore, it showed to be impossible to use flux densities calculated by Darcy-Buckingham equation in the order to prove existence of different infiltration rates in level terraces. This conclusion was reinforced due to the highly variable surface conditions in the terrace canal. A methodology to measure water contents within the depositions in the canal should be developed to increase the precision of water storage estimation. Infiltration rates in the terrace canal cannot be estimated by storage variation alone, due to the important role of drainage and, possibly, ascension of water in the terrace hill. A correct estimate of the infiltration rate in the canal, necessary for its dimensioning, should combine a high number of repetitions with the measurement of water content within the layer of deposits over the terrace canal surface along time.
Galdino, Sérgio. "Estimativa da perda de terra sob pastagens cultivadas em solos arenosos da bacia hidrográfica do alto Taquari - MS/MT". [s.n.], 2012. http://repositorio.unicamp.br/jspui/handle/REPOSIP/256830.
Pełny tekst źródłaTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agrícola
Made available in DSpace on 2018-08-20T22:57:38Z (GMT). No. of bitstreams: 1 Galdino_Sergio_D.pdf: 11328709 bytes, checksum: e5e5fc6d26b74b20826ad8a8bc4a4cef (MD5) Previous issue date: 2012
Resumo: O assoreamento do rio Taquari constitui grave problema ambiental e socioeconômico do Pantanal Brasileiro e decorre principalmente da erosão acelerada do solo ocupado com pastagens degradadas na parte alta da bacia. Um dos modelos mais utilizado para estimar a perda média anual de solo é a Equação Universal de Perda de Solo (USLE). Novas pesquisas foram realizadas para melhorar as estimativas do modelo, originando a Equação Universal de Perda de Solo Revisada (RUSLE). A principal mudança foi na forma de determinação do fator de uso e manejo do solo (C). Na USLE o fator C é obtido a partir do monitoramento constante da perda de solo em parcelas experimentais durante vários anos, constituindo sério empecilho a sua determinação, principalmente no Brasil. Na RUSLE o fator C para pastagens é estimado mais rapidamente, a partir de levantamentos de parâmetros do solo e da vegetação. O objetivo geral do trabalho foi ajustar os fatores da RUSLE às condições locais da bacia do alto Taquari (BAT) e estimar as taxas de perda de solo por erosão, para posterior estudo de cenários de manejo e identificação das práticas mais protetoras dos solos na bacia. O estudo compreendeu áreas de pastagens cultivadas em solos arenosos da BAT. Os parâmetros necessários para estimativas da razão de perda de solo (SLR) e fator C da RUSLE foram levantados em nove parcelas (pastagens) em duas épocas do ano. Análise da SLR e do fator C identificaram valores de C representativos de pastagem não degradada e com níveis de degradação; baixo/médio e alto. Na espacialização do fator C na BAT utilizou-se o modelo linear de mistura espectral. Para a estimativa das perdas de solo nas áreas de pastagens também foram espacializados os demais fatores da RUSLE. A erosividade das chuvas (Fator R) foi estimada a partir de registros mensais e anuais de precipitação de postos pluviométricos localizados na BAT e entorno. Na estimativa da erodibilidade do solo (Fator K) foram utilizados parâmetros físico-químicos do solo levantados no campo. O fator topográfico (LS da RUSLE) foi obtido empregando algoritmo de contribuição de área a montante e modelo digital de elevação do Banco de Dados Geomorfométricos do Brasil (TOPODATA). O fator de práticas conservacionistas do solo (Fator P) foi considerado unitário na estimativa da perda de solo atual na BAT. Também foram estimadas as perdas de solo para dois cenários futuros de manejo adequado do solo e da pastagem. Resultado evidenciou que os valores do fator C estimados pela RUSLE para pastagens se assemelham àqueles determinados pela USLE. A média da perda de solo nas pastagens da BAT em 2010 foi estimada em 9,638 Mg ha-1 ano-1. O estudo de cenários permitiu uma redução em até 75,97% das taxas de perda de solo por erosão com a implementação de manejo adequado do solo e da pastagem. Conclui-se que a RUSLE apresenta bom potencial de estimativa do fator de uso e cobertura do solo, e que se ajustou bem às condições locais da BAT na estimativa da perda de solo
Abstract: The river siltation Taquari constitutes serious environmental and socioeconomic problem of the Brazilian Pantanal and arises principally from accelerated erosion of land occupied by degraded pastures in the upper basin. One of the models used to estimate the average annual soil loss is the Universal Soil Loss Equation (USLE). New research has been done to improve the model estimates, yielding the Revised Universal Soil Loss Equation (RUSLE). The main change was in the method determines the use and soil management factor (C). With USLE, the C factor is obtained from the constant monitoring of soil loss in plots for several years, constituting serious impediment to their determination, especially in Brazil. With RUSLE, the C factor for pastures is estimated sooner, using surveys of soil parameters and vegetation. The overall goal of this work was to adjust RUSLE factors to upper Taquari basin (UTB) local conditions and to estimate soil loss rates due to erosion, for further management scenarios studies and more protective soil identification practices in the basin. The study included pastures grown on sandy soils of the UTB. The required parameters for soil loss ratio estimates (SLR) and the RUSLE C factor were raised in nine plots (pastures) in two seasons. Further SLR analysis identified C factor values for non-degraded, low, medium and highly degraded pasture levels. C factor spatialization for the UTB used the linear spectral mixture model. To estimate soil loss in grazing areas other RUSLE factors were also spatialized. The rainfall erosivity factor (R) was estimated from records of monthly and annual precipitation of rain gauge stations located in and around the UTB. For soil erodibility (K factor) estimation, physic-chemical soil parameters collected in the area were used. The topographic factor (LS RUSLE) was obtained using algorithm contribution of the upstream area and Brazilian geomorphometric digital elevation model data from TOPODATA. The soil conservation practices factor (P) unit was considered estimating soil loss in the UTB. Two future soil loss scenarios were also estimated. Results showed that the C factor values estimated by RUSLE for pastures resemble those determined by USLE. The average soil loss in the pastures of the UTB in 2010 was estimated at 9.638 Mg ha-1 yr-1. The scenario study allowed for a reduction up to 75.97% in the rates of soil loss due to erosion by implementing proper soil and pasture management. We conclude that the RUSLE estimation shows good potential for land use techniques, which fits well into the UTB local conditions and in the estimation of soil loss
Doutorado
Planejamento e Desenvolvimento Rural Sustentável
Doutor em Engenharia Agrícola
Dissart, Jean-Christophe. "The economics of erosion and sustainable practices : the case of the Saint-Esprit watershed". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape10/PQDD_0006/MQ44158.pdf.
Pełny tekst źródłaPsaris, Alexander Michael. "Assessing Hydrologic and Water Quality Sensitivities to Precipitation Changes, Urban Growth and Land Management Using SWAT". PDXScholar, 2014. https://pdxscholar.library.pdx.edu/open_access_etds/1783.
Pełny tekst źródłaZhong, Yiming. "Modelling sediment transportation and overland flow". Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:a45eefae-5a0f-4917-9abb-261ae792f2ee.
Pełny tekst źródłaKarimov, Vladimir Rustemovich. "Mathematical modeling of ephemeral gully erosion". Diss., Kansas State University, 2017. http://hdl.handle.net/2097/38230.
Pełny tekst źródłaDepartment of Biological & Agricultural Engineering
Aleksey Y. Sheshukov
As the world faces an increasing demand for food due to the growing global population and the pernicious effects of land degradation, there is a need to overcome this challenge by using sustainable management practices for agricultural productions. One of the problems, which sustainable agriculture seeks to address, is the loss of topsoil due to soil erosion. Changing weather patterns also contribute to the average annual rainfall across the globe with an excess precipitation, which creates runoff and causes soil erosion. One of the significant yet less studied types of soil erosion is ephemeral gully erosion. Formed by the concentrated overland flow during intensive rainfall events, ephemeral gullies are channels on agricultural fields that can be removed by tillage operations but appear at the same location every year. Even though simplified ephemeral gully models estimate soil losses, they do not account for complicated hydrological and soil erosion processes of channel formations. The purpose of this research work is to investigate sediment sources and develop tools that can predict ephemeral gully erosion more efficiently. To achieve this goal, an experimental study was conducted on an agricultural field in central Kansas by tracking channel development, monitoring soil moisture content, and recording the amount of rainfall. Runoff and sediment loads from contributing catchment and critical and actual shear stresses were estimated by the computer model, and conclusions were made on the effect of saturation dynamics on the erosion processes. Furthermore, a two-dimensional subsurface water flow and soil erosion model was developed with the variable soil erodibility parameters which account for the subsurface fluxes and the effects on the soil detachment process. The model was applied to study the impacts of variable soil erodibility parameters on the erosion process for different soils and various antecedent soil moisture conditions. Also developed to estimate the soil losses at the field scale was an integrated spatially-distributed ephemeral gully model with dynamic time-dependent channel development. The model showed good fit by matching the experimental data. The results from this work can be used to advance the research of soil erosion prediction from concentrated flow channels and ephemeral gullies formed on agricultural fields.
Greener, Mark. "Incorporating sediment transport competence into existing soil erosion models". Thesis, University of Leicester, 2001. http://hdl.handle.net/2381/30393.
Pełny tekst źródłaFavis-Mortlock, David. "Use and abuse of soil erosion models in Southern England". Thesis, University of Brighton, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.260393.
Pełny tekst źródłaMa, Ning. "Mathematical Modelling of Water Soil Erosion and Sediment Yield in Large Catchments". Thesis, Link to the online version, 2006. http://hdl.handle.net/10019/575.
Pełny tekst źródłaBobe, Bedadi Woreka. "Evaluation of soil erosion in the Harerge region of Ethiopia using soil loss models, rainfall simulation and field trails". Pretoria : [s.n.], 2004. http://upetd.up.ac.za/thesis/available/etd-08022004-141533.
Pełny tekst źródłaBarrett, Gary Edward. "Infiltration in water repellent soil". Thesis, University of British Columbia, 1988. http://hdl.handle.net/2429/28618.
Pełny tekst źródłaArts, Faculty of
Geography, Department of
Graduate
Crudge, Steven. "Quantification of rill erosion using field measurements and remote sensing techniques". Thesis, University of British Columbia, 1987. http://hdl.handle.net/2429/26196.
Pełny tekst źródłaLand and Food Systems, Faculty of
Graduate
Sorooshian, Soroosh, i Vijai Kumar Gupta. "Improving the Reliability of Compartmental Models: Case of Conceptual Hydrologic Rainfall-Runoff Models". Department of Hydrology and Water Resources, University of Arizona (Tucson, AZ), 1986. http://hdl.handle.net/10150/614011.
Pełny tekst źródłaRomanel, Celso 1952. "DYNAMIC SOIL-STRUCTURE INTERACTION IN A LAYERED MEDIUM". Thesis, The University of Arizona, 1987. http://hdl.handle.net/10150/276511.
Pełny tekst źródłaChoi, Daniel Mintae. "Rainfall intensity and soil erosion by water : limitations of current erosion models and implications for erosion model-based studies under future climates". Thesis, University of Oxford, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.604890.
Pełny tekst źródłaSun, Hua. "Digital terrain modelling of catchment erosion and sedimentation /". Title page, contents and abstract only, 1998. http://web4.library.adelaide.edu.au/theses/09PH/09phs9565.pdf.
Pełny tekst źródłaPark, Soojin. "Modelling soil-landform continuum on a three-dimensional hillslope". Thesis, University of Oxford, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.670238.
Pełny tekst źródłaMtundu, Nangantani Davies Godfrey. "The Stochastic Behavior of Soil Moisture and Its Role in Catchment Response Models". PDXScholar, 1987. https://pdxscholar.library.pdx.edu/open_access_etds/527.
Pełny tekst źródłaMusa, Zulkarnain 1964. "An accelerated conjugate direction procedure for slope stability analysis". Thesis, The University of Arizona, 1988. http://hdl.handle.net/10150/276912.
Pełny tekst źródłaRomanel, Celso. "A global-local approach for dynamic soil-structure interaction analysis of deeply embedded structures in a layered medium". Diss., The University of Arizona, 1989. http://hdl.handle.net/10150/184762.
Pełny tekst źródłaSande, Leif Andrew. "Experimental Studies on Infiltration/Soil-Water Movement Processes and Green-AMPT Modeling". Thesis, North Dakota State University, 2011. https://hdl.handle.net/10365/29329.
Pełny tekst źródłaNational Science Foundation (Grant No. EAR-0907588)
Hendrickson, Jene Diane, i Soroosh Sorooshian. "CALIBRATION OF RAINFALL-RUNOFF MODELS USING GRADIENT-BASED ALGORITHMS AND ANALYTIC DERIVATIVES". Department of Hydrology and Water Resources, University of Arizona (Tucson, AZ), 1987. http://hdl.handle.net/10150/614186.
Pełny tekst źródłaIbrahim, Norkhair. "An analysis of the sensitivity of soil erosion models within a geographical information system". Thesis, University of Nottingham, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.243472.
Pełny tekst źródłaHuang, Xin, i 黃昕. "Exploring critical-state behaviour using DEM". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2014. http://hdl.handle.net/10722/206742.
Pełny tekst źródłapublished_or_final_version
Civil Engineering
Doctoral
Doctor of Philosophy
Bobe, Bedadi Woreka. "Evaluation of soil erosion in the Harerge region of Ethiopia using soil loss models, rainfall simulation and field trials". Thesis, University of Pretoria, 2004. http://hdl.handle.net/2263/26929.
Pełny tekst źródłaThesis (PhD (Soil Science))--University of Pretoria, 2004.
Plant Production and Soil Science
unrestricted
Galadima, A., i J. C. Silvertooth. "Mathematical Models of Potassium Release Kinetics for Sonoran Desert Soils of Arizona". College of Agriculture, University of Arizona (Tucson, AZ), 1998. http://hdl.handle.net/10150/210381.
Pełny tekst źródłaHashem, Nadeem. "Use of high resolution remote sensing and GIS to parameterise spatially-distributed soil erosion models". Thesis, King's College London (University of London), 2002. https://kclpure.kcl.ac.uk/portal/en/theses/use-of-high-resolution-remote-sensing-and-gis-to-parameterise-spatiallydistributed-soil-erosion-models(de9a0828-c481-4b60-8acf-c2664f1ee1f1).html.
Pełny tekst źródłaZhao, Qian, i 赵倩. "A thermomechanical approach to constitutive modeling of geomaterials". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B47166836.
Pełny tekst źródłapublished_or_final_version
Civil Engineering
Master
Master of Philosophy
He, Shu Yu. "Field study on influence of atmospheric parameters and vegetation on variation of soil suction around tree vicinity". Thesis, University of Macau, 2018. http://umaclib3.umac.mo/record=b3868734.
Pełny tekst źródłaWade, Charles Robert. "Evaluation of Best Management Practices for Bladed Skid Trail Erosion Control and Determination of Erosion Model Accuracy and Applicability". Thesis, Virginia Tech, 2010. http://hdl.handle.net/10919/35714.
Pełny tekst źródłaMaster of Science
Richard, Paul François. "A computer analysis of the flow of water and nutrients in agricultural soils as affected by subsurface drainage". Thesis, University of British Columbia, 1988. http://hdl.handle.net/2429/29171.
Pełny tekst źródłaScience, Faculty of
Resources, Environment and Sustainability (IRES), Institute for
Graduate
Ahmad, Faheem. "Numerical modelling of transport of pollutant through soils". Thesis, This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-08182009-040239/.
Pełny tekst źródłaLiu, Ying, i 劉影. "Limit equilibrium methods for slope stability analysis". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2002. http://hub.hku.hk/bib/B42576684.
Pełny tekst źródłaAkinola, Akinrotimi Idowu. "Temporal and Thermal Effects on Fluvial Erosion of Cohesive Streambank Soils". Diss., Virginia Tech, 2018. http://hdl.handle.net/10919/96768.
Pełny tekst źródłaPHD
Sun, Tek-kei, i 孫廸麒. "Numerical modeling of skin friction and penetration problems in geotechnical engineering". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2013. http://hdl.handle.net/10722/195991.
Pełny tekst źródłapublished_or_final_version
Civil Engineering
Doctoral
Doctor of Philosophy
SOMASUNDARAM, SUJITHAN. "CONSTITUTIVE MODELLING FOR ANISOTROPIC HARDENING BEHAVIOR WITH APPLICATIONS TO COHESIONLESS SOILS (INDUCED, KINEMATIC, NON-ASSOCIATIVENESS)". Diss., The University of Arizona, 1986. http://hdl.handle.net/10150/188165.
Pełny tekst źródłaDavary, Kamran. "Soil moisture redistribution modeling with artificial neural networks". Thesis, McGill University, 2001. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=36905.
Pełny tekst źródłaAn initial review of existing soil hydrology models provided greater insight into current modelling challenges and a general classification of the models. The application of AI techniques as alternative tools for soil hydrology modelling was explored.
A one-dimensional (1D) model based on ANN and FIS was developed. To estimate fluxes more accurately, multiple ANNs were trained and combined by way of an FIS. The main body of the model employed the ANN-FIS module to model soil moisture redistribution throughout the profile. When tested against the SWAP93 model, the ANN-FIS model gave a good match and maximum error of <8%; however, it did not show a notable computation cost shift.
The investigation proceeded with development of another ANN-based 1D modelling approach. This time, the soil profile or flow region, regardless of its depth, was divided into ten equal parts (compartments). The ANN was trained to estimate moisture patterns for a whole soil profile, from the previous day's soil moisture pattern and boundary conditions, and the current day's boundary conditions. The model was tested against SWAP93 where an average SCORE of 90.4 indicated a good match. The computation cost of the ANN-based model was about one-third that of SWAP93.
At this point the study sought to develop a 3D modelling approach. The ANN was trained to estimate the nodal soil moisture changes through time under the influence of six neighbouring nodes (in a 3D space, two on each axis). The model's accuracy was tested against the SWMS-3D model. An average SCORE of 91 and a 15-fold decrease in computation costs showed a quite acceptable performance. Results suggest that this approach is potentially capable of realistically modelling 3D VSSM redistribution with less computation time.
Finally, pros and cons of these ANN-based modelling approaches are compared and contrasted, and some recommendations on future work are given.
Chin, Victor B. L. "The dynamic response of pile-soil interfaces during pile driving and dynamic testing events". Monash University, Dept. of Civil Engineering, 2003. http://arrow.monash.edu.au/hdl/1959.1/9421.
Pełny tekst źródłaOdeh, Inakwu Ominyi Akots. "Soil pattern recognition in a South Australian subcatchment /". Title page, contents and abstract only, 1990. http://web4.library.adelaide.edu.au/theses/09PH/09pho23.pdf.
Pełny tekst źródłaDeknatel, William Brockway. "USE OF THE SOLUTION MODELS TO CALCULATE THE ACTIVITY COMPOSITION RELATIONS OF MAGNESIAN CALCITES (SOLID, CARBONATES)". Thesis, The University of Arizona, 1985. http://hdl.handle.net/10150/291512.
Pełny tekst źródłaAbou, Nahra Joumana. "Modeling phosphorus transport in soil and water". Thesis, McGill University, 2006. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=102946.
Pełny tekst źródłaThe ability of the NICA model to describe phosphate (PO4) adsorption to soil particles was tested using soils collected from agricultural fields in southern Quebec. The surface charge and PO4 adsorption capacity of these soils were measured. Results were used to estimate the NICA model parameters using a non-linear fitting function. The NICA model accurately described the surface charge of these soils and the PO4 adsorption processes.
The HYDRUS-1D model was applied to simulate water flow and PO4 transport in re-constructed soil column experiments. The HYDRUS-1D model was calibrated based on physical and chemical parameters that were estimated from different experiments. Overall, the HYDRUS-1D model successfully simulated the water flow in the columns; however, it overestimated the final adsorbed PO4 concentrations in the soil. The discrepancies in the results suggested that the HYDRUS-1D model could not account for the differences in the soil structure found in the columns, or that the Freundlich isotherm could not adequately describe PO4 adsorption.
The HYDRUS-NICA model was calibrated and validated with results from re-packed column experiments. The simulated results were then compared with results obtained by the HYDRUS-1D model. The overall goodness-of-fit for the HYDRUS-1D model simulations was classified as poor. The HYDRUS-NICA model improved significantly the prediction of PO4 transport, with the coefficient of modeling efficiency values being close to unity, and the coefficient of residual mass values being close to zero. The HYDRUS-NICA model can be used as a tool to improve the prediction of PO4 transport at the field scale.
Yamamoto, Nobutaka. "Numerical analysis of shallow circular foundations on sands". University of Western Australia. School of Civil and Resource Engineering, 2006. http://theses.library.uwa.edu.au/adt-WU2006.0038.
Pełny tekst źródłaFaria, Rogério Teixeira de. "Simulation of irrigation requirements for Parana State, Brazil". Thesis, McGill University, 1993. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=41290.
Pełny tekst źródłaA crop yield model based on the stress day index approach was selected from an evaluation of seven crop-water production functions using wheat field data. This model was combined with the soil moisture model to assess risks of drought during the establishment and development of non-irrigated wheat crops with different planting dates. Irrigation management strategies were simulated to identify net system delivery capacities and application frequencies that promote maximum yield with minimum requirements of water. Yield reductions in non-irrigated wheat due to water stress varied between 16%, for early plantings, to 50%, for late plantings. Maximum yields with minimum applied water was obtained by the use of low intensity (5 to 10 mm) and frequent (3 to 5 days) irrigations. System delivery capacity requirements varied from 1.5 to 3.0 mm/day, according to planting dates.