Consulta: subjectFacets:"Simulation models"
Registros recuperados: 35
Data/hora: 06/06/2024 01:33:37

Potencial para producir Jatropha curcas L. como materia prima para biodiésel en el estado de Veracruz.
Provedor de dados: 32
Autores: Inurreta Aguirre, Héctor Daniel.
Existe gran interés alrededor del mundo en utilizar el aceite de Jatropha curcas L. como materia prima para biodiésel; sin embargo, con el fin de aumentar la eficiencia energética y económica de su cultivo, es necesario identificar áreas con condiciones agroecológicas óptimas y estimar su productividad en zonas marginales para evitar competencia con la producción de alimentos. El objetivo de este trabajo fue conocer la variación del potencial productivo de Jatropha curcas L. en respuesta a las distintas condiciones edafoclimáticas del estado de Veracruz. Se utilizó el modelo Soil and Water Assessment Tool (SWAT) para simular el rendimiento de semilla de Jatropha curcas L. Las unidades de cálculo fueron las Unidades de Respuesta Hidrológica (URH), definidas...
Palavras-chave: SWAT; Modelos de simulación; Zonificación; SIG; Simulation models; Zoning; GIS; Agroecosistemas locales; Maestría.
Ano: 2012
URL: http://hdl.handle.net/10521/1700

Zonificación del potencial productivo de biomasa para etanol de segunda generación en agroecosistemas con pasto Pennisetum purpureum en el estado de Veracruz.
Provedor de dados: 32
Autores: López Escudero, Roberto de Jesús.
El etanol lignocelulósico generado a partir de la biomasa seca de especies como Pennisetum purpureum puede ser la solución a problemáticas actuales como la crisis energética, la ineficiencia de los biocombustibles de primera generación, el desplazamiento de tierras destinadas al sustento humano y el cambio en el uso de los suelos. Sin embargo, con la finalidad de aumentar la eficiencia energética de esta especie, es necesario identificar áreas con condiciones agroecológicas óptimas que no compitan con la producción de alimentos. Por lo anterior el objetivo de este trabajo fue cartografiar y generar un índice de productividad de Pennisetum purpureum con base a las condiciones agroecológicas del estado de Veracruz. Se utilizó el modelo Soil and Water...
Palavras-chave: Etanol; Pennisetum purpureum; Modelos de simulación; SWAT; URH; Ethanol; Simulation models; Agroecosistemas Tropicales; Maestría.
Ano: 2014
URL: http://hdl.handle.net/10521/2343

Evaluación de tres genotipos de cebada maltera en el estado de Hidalgo
Provedor de dados: 32
Autores: Gómez Mercado, René.
Los modelos de simulación para establecer el rendimiento de cultivos requieren de  información no siempre disponible para cubrir los requerimientos de predicción, que  explican de manera teórica los fenómenos que influyen en el rendimiento. La  información faltante se refiere al  tipo de cultivares (fenología, fisiología y genética) y  su interacción con el clima y los suelos. El objetivo del presente estudio fue simular el  crecimiento, desarrollo y rendimiento, para evaluar la producción de materia seca  y  su relación con el  rendimiento y determinar diferencias entre genotipos por medio del  uso de modelos de simulación dinámica como una herramienta de investigación.  La  metodología propuesta parte del método de la FAO para estimar el rendimiento con...
Tipo: Tesis
Palavras-chave: Materia seca; Modelos de simulación; Hordeum vulgare; Doctorado; Edafología; Dry matter; Simulation models.
Ano: 2008
URL: http://hdl.handle.net/10521/1484

Delivering the Goods: Scaling out Results of Natural Resource Management Research
Provedor de dados: 7
Autores: Harrington, Larry; International Maize and Wheat Improvement Center (CIMMYT); l.harrington@cgiar.org; White, Jeffrey; ; j.white@cgiar.org; Grace, Peter; Sinclair Knight Merz, Brisbane, Australia; pgrace@skm.com.au; Hodson, David; ; d.hodson@cgiar.org; Hartkamp, Agnes Dewi; Product Organisation Grains, Seeds and Pulses, The Hague, Netherlands; d.hartkamp@wisint.org; Vaughan, Christopher; CO MET Directorate of Environmental Affairs, Namibia; kit@africaonline.com.na; Meisner, Craig; ; cmeisner@bttb.net.bd.
To help integrated natural resource management (INRM) research "deliver the goods" for many of the world's poor over a large area and in a timely manner, the authors suggest a problem-solving approach that facilitates the scaling out of relevant agricultural practices. They propose seven ways to foster scaling out: (1) develop more attractive practices and technologies through participatory research (2) balance supply-driven approaches with resource user demands, (3) use feedback to redefine the research agenda, (4) encourage support groups and networks for information sharing, (5) facilitate negotiation among stakeholders, (6) inform policy change and institutional development, and (7) make sensible use of information management tools, including models...
Tipo: Peer-Reviewed Reports
Palavras-chave: Mexico; South Asia; Southern Africa; Conservation tillage; Diffusion of research; Environments; Geographic information systems; Natural resource management; Participatory research; Scaling out; Simulation models; Technology transfer.
Ano: 2001

Ecological and Social Dynamics in Simple Models of Ecosystem Management
Provedor de dados: 7
Autores: Carpenter, Stephen R; University of Wisconsin-Madison; srcarpen@wisc.edu; Brock, William; University of Wisconsin; brock@macc.wisc.edu; Hanson, Paul; University of Wisconsin; pchanson@facstaff.wisc.edu.
Simulation models were developed to explore and illustrate dynamics of socioecological systems. The ecosystem is a lake subject to phosphorus pollution. Phosphorus flows from agriculture to upland soils, to surface waters, where it cycles between water and sediments. The ecosystem is multistable, and moves among domains of attraction depending on the history of pollutant inputs. The alternative states yield different economic benefits. Agents form expectations about ecosystem dynamics, markets, and/or the actions of managers, and choose levels of pollutant inputs accordingly. Agents have heterogeneous beliefs and/or access to information. Their aggregate behavior determines the total rate of pollutant input. As the ecosystem changes, agents update their...
Tipo: Peer-Reviewed Reports
Palavras-chave: Adaptive agent models; Adaptive management; Bounded rationality; Ecological economics; Ecosystem oscillations; Integrated models; Lake eutrophication; Nonpoint pollution; Phosphorus cycles; Simulation models; Social-natural systems.
Ano: 1999

Environmental and Management Constraints on Tourism in Varna Bay, Bulgarian Black Sea Coast
Provedor de dados: 7
Autores: Moncheva, Snejana; IO-BAS; snejanam@abv.bg; Racheva, Eleonora; IO-BAS; ainsteim@abv.bg; Kamburska, Lyudmila; EC DG-JRC, Institute for Environment and Sustainability; lyudmila.kamburska@jrc.it.
We used the systems approach framework (SAF) to study the conflict between the development of tourism and marine environmental quality in Varna Bay, a critical regional policy issue selected for study after stakeholder consultation. Water quality is of central importance to the tourism industry, as a minimum level of water clarity is required to make the water attractive for swimming and bathing. Rampant development of coastal resorts in Varna Bay has led to water-quality deterioration because the tourism capacity has expanded without concurrent increases in the capacity to collect and treat sewage. We used a numerical model to simulate the Secchi depth (as a proxy for transparency) as a function of the nitrogen loading and total suspended solids. The SAF...
Tipo: Peer-Reviewed Reports
Palavras-chave: Black Sea; Coastal tourism; Eutrophication; Simulation models; Systems approach.
Ano: 2012

Produtividade potencial e variabilidade da produtividade de milho, em regime de sequeiro, em Rio Verde, Goiás.
Provedor de dados: 14
Autores: SILVA, P. P. G. da; ANDRADE, C. de L. T. de; MAGALHÃES, B. G.; GONTIJO NETO, M. M.; MELO, B. F. de.
A cultura do milho, quando sujeita a instabilidades climáticas, pode sofrer reduções severas no rendimento de grãos. O entendimento e a quantificação dos riscos climáticos envolvidos na produção de milho é, portanto, o primeiro passo para que se estabeleçam estratégias de manejo que possam minimizar esses riscos. Objetivou-se com este trabalho avaliar a variabilidade interanual da produtividade e a diferença entre a produtividade potencial e atingível de milho de sequeiro, para diferentes datas de semeadura, na safra e safrinha, em Rio Verde, Goiás. Empregou-se o modelo CSM-CERES-Maize, previamente parametrizado, juntamente com 33 anos de dados históricos diários de clima para simular cenários de épocas de semeadura, na safra e safrinha, e para avaliar a...
Tipo: Boletim de Pesquisa e Desenvolvimento (INFOTECA-E)
Palavras-chave: Seeding; Modelo de simulação; Semeadura; Zea mays; Simulation models; Sowing.
Ano: 2016
URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/1055932

Uma metodologia alternativa para o zoneamento de risco climático da cultura do milho.
Provedor de dados: 14
Autores: ANDRADE, C. de L. T. de; PAIXÃO, J. de S.; STEIDLE NETO, A. J.; AMARAL, T. A.; PIMENTA, F. M.; GARCIA Y GARCIA, A.; MARIN, F. R.; SILVA, D. F.
Produzir milho sob condições de sequeiro é uma prática comum no Brasil. Neste sistema, de produção as culturas são fortemente afetadas pela inerente variabilidade climática anual e interanual, especialmente pelos veranicos, que afetam a produtividade. Uma das estratégias mais simples, com praticamente nenhum custo, para mitigar este problema é a determinação de uma janela de semeadura, que minimize os efeitos negativos da variabilidade climática na agricultura de sequeiro. Os objetivos deste estudo foram: a) usar os resultados de produtividade de milho simulada com um modelo baseado em processos, para estabelecer janelas de semeadura e b) comparar os resultados obtidos com a atual metodologia empregada pelo Ministério da Agricultura, Pecuária e...
Tipo: Boletim de Pesquisa e Desenvolvimento (INFOTECA-E)
Palavras-chave: Modelo de simulação; Semeadura; Zea mays; Simulation models; Sowing.
Ano: 2013
URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/974352

Modelagem de sistemas no CPA Trópico Úmido.
Provedor de dados: 14
Autores: DUTRA, S.; KITAMURA, P. C.
bitstream/item/197899/1/FL01584.pdf
Tipo: Outras publicações técnicas (INFOTECA-E)
Palavras-chave: Manejo de pastagem; Engorda de gado; Grassland management; Fattening; Modelo de Simulação; Cattle; Simulation models.
Ano: 1982
URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/375586

Estudos de simulação da movimentação vertical de herbicidas em solos com cana-de-açúcar na microbacia do córrego Espraiado Ribeirão Preto, SP.
Provedor de dados: 14
Autores: PESSOA, M. C. P. Y.; GOMES, M. A. F.; SOUZA, M. D. de; CERDEIRA, A. L.; NEVES, M. C.; NICOLELLA, G.
Este trabalho teve por objetivo um estudo de simulação, utilizando o CMLS-94, em área de agricultura intensiva de cana-de-açúcar, localizada na microbacia do córrego Espraiado em Ribeirão Preto (SP), de importância internacional, dada a presença do Aquífero Botucatu (Guarani). Os dados referentes a cultura de cana-de-açúcar tipo soqueira, predominante na área, aos principais tipos de solo na área estudada, quais sejam Latossolo Roxo (LR), Latossolo Vermelho-Escuro (LE) e Areia Quartzosa (AQ), foram incorporados as bases de dados do CMLS-94, assim como a informação do nome do arquivo contendo dados climáticos diários de Ribeirão Preto (SP) (período 1986-1989). Os herbicidas utilizados foram atrazina, tebuthiuron e diuron, por serem os mais usados na área de...
Tipo: Folhetos
Palavras-chave: Agricultura intensiva; Águas subetrrâneas; Lençoal freático; Herbicida; Simulação; Qualidade da água; Agrotóxico; Solo; Contaminação; Cana de açúcar; Atrazina; Herbicides; Environmental fate; Simulation models; Diuron; Tebuthiuron.
Ano: 1999
URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/13121

Modelación del arroz en Latinoamérica: estado del arte y base de datos para parametrización.
Provedor de dados: 14
Autores: REBOLLEDO-CID, M. C.; RAMÍREZ-VILLEGAS, J.; GRATEROL-MATUTE, E.; HERNÁNDEZ-VARELA, C. A.; RODRÍGUEZ-ESPINOZA, J.; PETRO-PÁEZ, E. H.; PINZÓN, S.; HEINEMANN, A. B.; RODRÍGUEZ-BAIDE, J. M.; VAN DEN BERG, M.
El arroz en Latinoamérica y el Caribe (LAC) es un cultivo de gran importancia social y económica. El consumo de arroz en LAC ha aumentado significativamente durante los últimos años, registrando un promedio actual de 30 kg persona-1 año-1. La particularidad del arroz producido en LAC está en una alta calidad de grano y una producción que se realiza en su mayoría bajo sistemas mecanizados con siembra directa. En LAC, el arroz es producido bajo riego y secano dentro de diferentes eco-regiones (templado, tropical húmedo, tropical seco). La seguridad alimentaria y el cambio climático constituyen un reto para la producción de arroz en LAC, elevando la necesidad de aumentar, pero a su vez estabilizar los rendimientos y la calidad del grano. La modelación de...
Tipo: Livro técnico (INFOTECA-E)
Palavras-chave: América Latina; Arroz; Oryza sativa; Modelo de simulação; Rice; Simulation models; Climate change; Calibration.
Ano: 2018
URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/1090979

Análise de sensibilidade do modelo de Caprio para simulação de evolução de resistência de pragas a toxinas BT.
Provedor de dados: 14
Autores: MAIA, A. de H. N.; DOURADO NETO, D.
bitstream/item/12262/1/documentos_76.pdf
Tipo: Documentos (INFOTECA-E)
Palavras-chave: Modelo de Caprio; Praga de planta; Resistência a pesticida; Modelo de simulação; Planta transgênica; Plant pests; Pesticide resistance; Simulation models; Transgenic plants.
Ano: 2009
URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/83084

Aptidão e potencial de produção de milho em municípios de Minas Gerais.
Provedor de dados: 14
Autores: PAIXÃO, J. de S.; ANDRADE, C. de L. T. de; SILVA, P. P. G. da; MAGALHÃES, B. G.; MELO, B. F.
A maior parte da produção de milho no Brasil ocorre em regime de sequeiro, tanto na primeira quanto na segunda safra, estando, portanto, sujeita a instabilidades climáticas que podem afetar o rendimento de grãos. Irregularidade no regime de chuvas, que induz estresse hídrico na cultura, é o principal fator responsável pela quebra da produtividade do milho no país. Algumas estratégias de manejo da cultura podem ser empregadas para atenuar este problema, entre as quais a escolha do período de semeadura adequado, preconizado no zoneamento de risco climático do Ministério da Agricultura, Pecuária e Abastecimento (Mapa). As ferramentas computacionais utilizadas no zoneamento necessitam, todavia, serem aprimoradas, principalmente em razão da nova era chamada...
Tipo: Documentos (INFOTECA-E)
Palavras-chave: Zea mays; Semeadura; Modelo de simulação; Sowing; Simulation models.
Ano: 2016
URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/1056084

Modeling pesticide movement in soils.
Provedor de dados: 14
Autores: SPADOTTO, C. A.
Resumo: A publicação sintetiza as discussões e contribuições resultantes da "lnternational Conference on Modeling Pesticide Movement in Soils" sobre a modelagem do movimento de pesticidas (agrotóxicos) nos solos com ênfase em ambientes tropicais e subtropicais , especialmente nas condições brasileiras de solo e clima.
Tipo: Documentos (INFOTECA-E)
Palavras-chave: Pesticide.; Belém (PA); Agrotóxico; Solo; Modelo de simulação; Modelo matemático.; Pesticides; Soil transport processes; Simulation models.
Ano: 2002
URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/1023292

Modelo de balanço de nitrogênio para cana-de-açúcar: fase I - análise teórica e ajustes.
Provedor de dados: 14
Autores: BERGAMASCO, A. F.; SILVA, F. C. da; RODRIGUES, L. H. A.; TRIVELIN, P. C. O.
O Brasil é o maior produtor mundial de cana-de-açúcar, sendo que a queima da palha do canavial visando facilitar a colheita ainda é muito praticada. Essa prática vem sendo questionada pela alta emissão de gases, além de provocar perdas de nutrientes para as plantas, facilitar o aparecimento de ervas daninhas e erosão. As maiores limitações à produtividade da cana-de-açúcar, estão relacionados à disponibilidade de quantidades adequadas de nutrientes minerais nos solos, com destaque ao nitrogênio (N), mas, sem a queima prévia da cana, a cobertura pela palhada irá provocar mudanças no manejo da cultura e na dinâmica do N. O uso da modelagem matemática reduz a necessidade de experimentos e facilita a sistematização de conhecimentos sobre esse tema. O modelo...
Tipo: Outras publicações técnicas (INFOTECA-E)
Palavras-chave: Cana-de-açúcar; Adubação nitrogenada; Balanço de nitrogênio.; Modelo Matemático; Simulação.; Mathematical models; Simulation models; Sugarcane; Nitrogen balance.
Ano: 2001
URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/8306

Estimating productivity of water at different spatial scales using simulation modeling
Provedor de dados: 31
Autores: Droogers,   Peter; Kite,   Geoff.
A clear understanding of the current water balance is required to explore options for water saving measures. However, measurement of all the terms in the water balance is infeasible in terms of spatial and temporal scale, but hydrological simulation models can fill the gap between measured and required data. For a basin in Western Turkey, simulation modeling at three different scales, field, irrigation scheme and basin scale, was performed to obtain all terms of the water balance. These water balance numbers were used to calculate the Productivity of Water at the three spatial levels distinguished to assess the performance of the systems.
Tipo: Report
Palavras-chave: Water resources; Productivity; Simulation models; Water scarcity; Water supply; Water balance; Performance indexes; Indicators; River basins; Cropping systems; Crop yield; Cotton; Hydrology; Economic analysis; Agribusiness; Agricultural Finance; Crop Production/Industries; Environmental Economics and Policy; Production Economics; Productivity Analysis; Research Methods/ Statistical Methods.
Ano: 2001
URL: http://purl.umn.edu/44568

Strategic Analyses of the National River Linking Project (NRLP) of India, Series 2; Proceedings of the Workshop on Analyses of Hydrological, Social and Ecological Issues of the NRLP
Provedor de dados: 31
Tipo: Conference Paper or Presentation
Palavras-chave: River basin development; Development projects; Irrigation programs; Hydrology; Erosion; Water transfer; Cost benefit analysis; Groundwater irrigation; Dams; Environmental effects; Water storage; Crop management; Livestock; Gender; Rainfed farming; Supplemental irrigation; Water harvesting; Artificial recharge; Water market; Simulation models; Water allocation; Case studies; Livestock Production/Industries; Production Economics; Productivity Analysis; Resource /Energy Economics and Policy.
Ano: 2008
URL: http://purl.umn.edu/118387

Market Impacts of Adopting Herbicide-Resistant Rice in the Southern United States
Provedor de dados: 31
Autores: Fuller,   Frank H.; Annou,   Mamane Malam; Wailes,   Eric J.
Herbicide-resistant (HR) rice varieties offer U.S. rice producers a powerful tool for control of red rice infestations.  However, improved weed control can shorten crop rotations and boost yields, resulting in expanded rice production and lower domestic market prices.  Declining market returns diminish the benefits of HR rice adoption and substantially reduce net returns for nonadopters.  More competitive prices increase U.S. rice exports, causing a slight decline in world rice prices.  The dependence of the rice marketing loan program on world prices prevents loan deficiency payments from adequately offsetting producers’ market revenue losses.  U.S. consumers gain from lower rice prices.
Tipo: Journal Article
Palavras-chave: Biotechnology; Crop rotation; Herbicide resistant; Red rice; Rice; Simulation models; Technology adaptation; Q11; Q16; Q18; O33; C53.
Ano: 2003
URL: http://purl.umn.edu/37859

Simulating impacts of irrigation on the hydrology of the Karagan Lagoon in Sri Lanka
Provedor de dados: 31
Autores: Stanzel,   Philipp; Oze,   Alexander; Smakhtin,   Vladimir U.; Boelee,   Eline; Droogers,   Peter.
Tipo: Working or Discussion Paper
Palavras-chave: Lagoons; Hydrology; Irrigation effects; Simulation models; Sensitivity analysis; Irrigation programs; Catchment areas; Tanks; Runoff; Precipitation; Evaporation; Seepage; Climate; Evapotranspiration; Paddy fields; Agricultural and Food Policy; Agricultural Finance; Crop Production/Industries; Environmental Economics and Policy; Resource /Energy Economics and Policy.
Ano: 2002
URL: http://purl.umn.edu/92698

The agro- structural change in the Alps and its outlook until 2020. A model based on key determinants
Provedor de dados: 31
Autores: Hoffmann,   Christian; Stiefenhofer,   Annika; Streifeneder,   Thomas.
The agro-structural change in the Alps has been gaining intensity steadily since 1980. Farms continuously feel the pressure to adapt to changed economic, political, and social conditions. Those diverge significantly between the different alpine countries but also within a country. Based on the developments so far, the current situation and expected future framework conditions, this paper intends to indicate possible developments for future agro-structural trends in the Alpine arc. Using multivariate regression analyses, significant indicators were derived from harmonised parameters on municipality level, which influence farm abandonment. They form the basis of the forecast of farm abandonment until 2020. Based on agro-economic scenarios from the project...
Tipo: Conference Paper or Presentation
Palavras-chave: Agro structural-change; Farm abandonment; Simulation models; Alps; Community/Rural/Urban Development; Q10.
Ano: 2010
URL: http://purl.umn.edu/95316

Improved water and land management in the Ethiopian highlands: its impact on downstream stakeholders dependent on the Blue Nile; Intermediate Results Dissemination Workshop February 5-6, 2009, Addis Ababa, Ethiopia
Provedor de dados: 31
Autores: Awulachew,   Seleshi Bekele; Erkossa,   Teklu; Smakhtin,   Vladimir U.; Fernando,   Ashra.
Tipo: Conference Paper or Presentation
Palavras-chave: River basin management; Watershed management; Farming systems; Water balance; Reservoirs; Water supply; Irrigation requirements; Irrigation programs; Simulation models; Sedimentation; Rainfall-Runoff relationships; Erosion; Soil water; Water balance; Soil conservation; Institutions; Organizations; Policy; Water governance; International waters; Institutional and Behavioral Economics; Land Economics/Use; Resource /Energy Economics and Policy.
Ano: 2009
URL: http://purl.umn.edu/118389

Evaluation of historic, current and future water demand in the Olifants River Catchment, South Africa
Provedor de dados: 31
Autores: McCartney,   Matthew P.; Arranz,   Roberto.
Water resource development has played a significant role in the expansion of agriculture and industry in the Olifants River Catchment. However, currently water deficit is one of the major constraints hampering development in the catchment; both the mining and agricultural sectors are producing below optimal levels because of their reliance on insufficient supplies. In this study, the Water Evaluation and Planning (WEAP) model was used to evaluate scenarios of historic, current and future water demand in the catchment. For each scenario, the WEAP model was used to simulate demand in five different sectors (rural, urban, mining, commercial forestry and irrigation) over a 70-year period of varying rainfall and hydrology. Levels of assured supply were...
Tipo: Report
Palavras-chave: River basins; Catchment areas; Water resources development; Water demand; Water allocation; Simulation models; Calibrations; Water use; Irrigation water; Domestic water; Ecology; South Africa; Olifants River Catchment; Agricultural and Food Policy; Community/Rural/Urban Development; Crop Production/Industries; Demand and Price Analysis; Environmental Economics and Policy; Farm Management; Labor and Human Capital; Land Economics/Use; Production Economics; Productivity Analysis; Research and Development/Tech Change/Emerging Technologies.
Ano: 2007
URL: http://purl.umn.edu/61095

Developing a hydrological model for the Mekong Basin: impacts of basin development on fisheries productivity.
Provedor de dados: 31
Autores: Kite,   Geoff.
Tipo: Working or Discussion Paper
Palavras-chave: Simulation models; Hydrology; River basins; Water resource management; Productivity; Flow; Fisheries; Mapping; Data collection; Computer techniques; Climate; Soil properties; Stream flow; Dams; Productivity Analysis; Resource /Energy Economics and Policy.
Ano: 2000
URL: http://purl.umn.edu/92781

FORECASTING YIELD AND PROFITABILITY OF MAIZE CROPPING SYSTEM USING SIMULATION MODELS IN UASIN GISHU, KENYA
Provedor de dados: 31
Autores: Odwori,   P.O.; Mapelu,   M.Z.; Odhiambo,   Mark O.; Nyangweso,   P.M.
Simulation models have been used successfully to forecast productivity of cropping systems under various weather, management and policy scenarios. These models have helped farmers make efficient resource allocation decisions. However, in Kenya simulation models have not been used extensively and more specifically in modeling maize cropping system. The study aimed at forecasting productivity and profitability of maize cropping system in Uasin Gishu district, Kenya. Both primary and secondary data were used. Both time series and cross-sectional data for variables of interest were collected and complemented by a survey of 20 maize farmers who were systematically selected to verify information obtained from secondary sources. Cropping Systems simulation model...
Tipo: Conference Paper or Presentation
Palavras-chave: Forecasting; Yields; Profits; Maize cropping system; Simulation models; Crop Production/Industries.
Ano: 2010
URL: http://purl.umn.edu/97080

Measuring the Effects of Trade Liberalization: Multilevel Analysis Tool for Agriculture
Provedor de dados: 31
Autores: Gerard,   Francoise; Marty,   Isabelle; Lancon,   Frederic; Versapuech,   Marion.
This book is the product of the projects "Farmers' Strategies Regarding Agricultural Diversification" (1993-1995) and "Agricultural Diversification and Food Crop Trade: Their Implications to Agricultural Policies in Southeast Asia" (1994-1996), both supported by CIRAD and the Government of France. It describes the first project attempting to apply the MATA methodology in a country like Indonesia. As constructed, the Multilevel Analysis Tool for Agriculture is able to answer various policy questions and gives the opportunity to users to make intensive simulations by themselves.
Tipo: Report
Palavras-chave: Simulation models; Economic analysis; Trade liberalization; Agriculture; International Relations/Trade.
Ano: 1998
URL: http://purl.umn.edu/32721

Evaluation of historic, current and future water demand in the Olifants River Catchment, South Africa.
Provedor de dados: 31
Autores: McCartney,   Matthew P.; Arranz,   Roberto.
Tipo: Report
Palavras-chave: River basins; Catchment areas; Water resources development; Water demand; Water allocation; Simulation models; Calibrations; Water use; Irrigation water; Domestic water; Ecology; South Africa; Olifants River Catchment; Agricultural and Food Policy; Community/Rural/Urban Development; Crop Production/Industries; Environmental Economics and Policy; Farm Management; Land Economics/Use; Resource /Energy Economics and Policy.
Ano: 2007
URL: http://purl.umn.edu/57026

China's Accession to the WTO: What Is at Stake for Agricultural Markets?
Provedor de dados: 31
Autores: Fuller,   Frank H.; Beghin,   John C.; de Cara,   Stephane; Fabiosa,   Jacinto F.; Fang,   Cheng; Matthey,   Holger.
We analyze the impact of China's accession to the World Trade Organization on major crop and livestock markets using the FAPRI modeling framework. We incorporate expected changes in consumer income, textile production, and trade policies as exogenous shocks to the baseline model. Following accession, revenues decline in China's livestock, grain, and oilseed industries, while cotton production prospers despite increased cotton imports. Chinese consumers benefit from lower food prices, with vegetable oil, dairy, and meat consumption increasing significantly. Argentina, Brazil, Canada, the European Union, and the United States are the greatest beneficiaries from expanded agricultural trade with China.
Tipo: Working or Discussion Paper
Palavras-chave: Accession; Agricultural trade; China; Policy analysis; Simulation models; Trade liberalization; World Trade Organization; International Relations/Trade.
Ano: 2001
URL: http://purl.umn.edu/18522

Agricultural water productivity: estimation at plot, farm and basin scale
Provedor de dados: 31
Autores: Cook,   Simon; Gichuki,   Francis; Turral,   Hugh.
Tipo: Working or Discussion Paper
Palavras-chave: Irrigated farming; Productivity; Estimation; Water balance; Water use; Simulation models; Water use efficiency; Livestock; Fisheries; Production Economics; Resource /Energy Economics and Policy.
Ano: 2006
URL: http://purl.umn.edu/91959

Improved water and land management in the Ethiopian highlands: its impact on downstream stakeholders dependent on the Blue Nile; Intermediate Results Dissemination Workshop February 5-6, 2009, Addis Ababa, Ethiopia
Provedor de dados: 31
Autores: Awulachew,   Seleshi Bekele; Erkossa,   Teklu; Smakhtin,   Vladimir U.; Fernando,   Ashra.
Tipo: Conference Paper or Presentation
Palavras-chave: River basin management; Water governance; Environmental flows; Simulation models; Reservoirs; Sedimentation; Rainfall-Runoff relationships; Hydrology; Water balance; Erosion; Soil conservation; Watersheds; Irrigation schemes; Water use; Environmental Economics and Policy; Land Economics/Use; Resource /Energy Economics and Policy.
Ano: 2009
URL: http://purl.umn.edu/118388

A Partial Equilibrium Model of the Beef and Dairy Sector in Italy Under Imperfect Competition
Provedor de dados: 31
Autores: Moro,   Daniele; Sckokai,   Paolo; Soregaroli,   Claudio.
In this paper we present a partial equilibrium model for the bovine sector (beef and dairy) in Italy, which can be used for simulation and forecasting. The structure of the model follows the vertical chain of the beef and dairy sector, allowing trade of both agricultural raw materials and final products. Since the processing and retailing stage is characterised by an imperfectly competitive structure, the model accounts for market power in modelling the price transmission mechanism. This provides further insights on the vertical transmission of shocks, both at the final level (i.e. the BSE crisis) and at the farm level (i.e. agricultural policy reform).
Tipo: Conference Paper or Presentation
Palavras-chave: Simulation models; Policy analysis; Imperfect competition; Beef; Dairy; Livestock Production/Industries.
Ano: 2002
URL: http://purl.umn.edu/24787

Determining the deficit coefficient as a function of irrigation depth and distribution uniformity
Provedor de dados: 91
Autores: Mantovani,Everardo C.; Faccioli,Gregório G.; Leal,Brauliro G.; Costa,Luis C.; Soares,Antônio A.; Freitas,Paulo S. L.
The present study aimed at the development of the water deficit coefficient as a function of the Christiansen uniformity coefficient and relationship between the applied water depth and that required by a given crop, taking into account that the water distribution by the sprinkler follows a normal distribution. Another objective was to compare the experimental results to those obtained through simulation with the Mantovani model. For this, the water deficit coefficients developed in this work were used, as well as the simplified coefficient that takes into account the water distribution by the sprinkler following a uniform distribution, and finally the development of the production functions for the bean crop by using the Mantovani model. The production...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Sprinkle; Simulation models; Bean crop.
Ano: 2010
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662010000300003

An expert system for planning and designing dairy farms in hot climates
Provedor de dados: 111
Autores: Mohamed Samer; Cairo University, Faculty of Agriculture, Department of Agricultural Engineering; Mohamed Hatem; Hartmut Grimm; Reiner Doluschitz; Thomas Jungbluth.
Eleven simulation models were developed to plan and design several dairy farm facilities.  Subsequently, an electronic spark map (decision tree) was developed for each simulation model, and then the simulation models were integrated into the relevant spark maps.  Afterwards, C# language (C Sharp), which is an object-oriented programming language, was used to develop an expert system via the simulation models and the electronic spark maps.  The developed expert system is able to plan and design several dairy farm facilities, e.g. housing system (corrals system), shade structure and roof material, concrete base, cooling system, milking parlour, forage storage, and manure handling system.  Subsequently, it plans the farmstead layout, and it leads to implement...
Palavras-chave: Expert systems; Simulation models; Spark maps; Precision livestock farming; Dairy cows.
Ano: 2012
URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/2088

Crop water requirements, biomass and grain yields estimation for upland rice using CROPWAT, AQUACROP and CERES simulation models
Provedor de dados: 111
Autores: Akinbile, Christopher Oluwakunmi.
This study estimated crop water requirements using CROPWAT while AQUACROP and CERES models evaluated performance in simulating biomass and grain yield of upland rice’s response to different irrigation schedule. NERICA 4 was subjected to five treatment given as: full (100%ET), good (80%ET), medium (60%ET), average (40%ET), and low (20%ET) and three replicates in a randomized block design. It was planted at the farmyard of the International Institute of Tropical Agriculture (IITA) Ibadan, Nigeria for two seasons 2015 and 2016 and the results of the first season was used in model calibration while second season’s result was used in validation. Biomass and grain yields values were obtained and compared with simulated values from AQUACROP and CERES and the...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: NERICA 4; Water requirements; Yield; Simulation models; Irrigation schedule.
Ano: 2020
URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/5636

Modelling Supplementation Strategies for Beef Steer Rearing and Fattening Systems in Southern Chile
Provedor de dados: 117
Autores: Toro,Paula; Catrileo,Adrián; Aguilar,Claudio; Vera,Raúl.
A mathematical model was developed to analyze beef production systems in Southern Chile. The study considered the identification of the main components of systems under different beef steer management strategies, using pasture with or without supplementation and back grounding cattle on pasture followed by a winter period of confined feeding with pasture silage and concentrates. Validation of model outputs using 200 kg LW Hereford steers against real experimental data showed no significant differences (P &amp;#8805; 0.01) between simulated and observed final weights. In order to analyze the interaction between the stocking rate (SR) and supplementation, three SR of 2, 2.5 and 3 steers ha-1 with and without pasture silage supplementation at the rate of 5 kg...
Tipo: Journal article
Palavras-chave: Beef cattle; Supplementation; Grazing systems; Simulation models.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000200010

Simulating the effect of climate on star grass growth and quality and its capacity to support milk production in the tropical regions of Mexico
Provedor de dados: 65
Autores: Angel,Gilberto Yong; Silveira,Vicente Celestino Pires; Nova,Francisca Avilés; Ortega,Octavio Alonso Castelán.
The objective of the present study was to simulate the effect of the seasonal variation of climate on the nutritional value and dry matter yield of star grass and its capacity to support milk production alone or with concentrate supplementation in small-scale milk production systems in the tropical regions of Mexico. Two mathematical simulation models were used, the first model simulates the growth and yield of star grass (Cynodon plectostachyus), and the second model simulates the productive performance of dairy cows. Both models were integrated in a decision-making support system (DSSTROP). Model's predictions were validated by a calibration exercise for each data set from three experiments on the effect of concentrate supplementation on milk yield. The...
Tipo: Info:eu-repo/semantics/other
Palavras-chave: Simulation models; Feeding strategies; Small-scale milk production.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782014000801486