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Browsing by Author "Srinivasan, R."

Now showing 1 - 8 of 8
  • Application of SWAT model to assess sub-watershed in Nghia Trung, Binh Phuoc Province, Vietnam
    Loi, N. K.; Nhat, T. T.; Quynh, T. L. N.; Ha, Dang Thanh; Reyes, Manuel R.; Srinivasan, R. (Ho Chi Minh City, Vietnam: Nong Lam University, 2009)
    Summary: The study uses the Soil and Water Assessment Tool to evaluate the impact of two land-use scenarios on sediment yield in the Nghia Trung sub-watershed. (Summary by record creator.)
  • Assessing regional impacts of change: Linking economic and environmental models
    Attwood, J.; McCarl, Bruce A.; Chen, Chi Chung; Eddleman, B.; Nayda, B.; Srinivasan, R. (Barking, England: Elsevier Science Ltd., 2000)
    There is an increasing demand for holistic analysis of proposed changes that addresses both environmental and economic factors and impacts. Because economic and environmental models typically have very different, seemingly irreconcilable structures, researchers may consider the expectations of policy makers unattainable. However, this paper presents a method for incorporating models with different spatial scales into a coherent national analysis. The authors combine an agricultural model with geographical boundaries on the state and county level and a watershed model with watershed boundaries. This method is the first to provide national analysis that includes economic results at the state and substate level and environmental results at the small watershed level. The example integrated model provides results for a national policy of cropland erosion control and dissemination of improved crop varieties by a state experiment station.
  • Assessment of environmental impacts of integrated vegetable-agroforestry (VAF) system in Nanggung, Bogor, Indonesia
    Raimadoya, M.; Reyes, Manuel R.; Srinivasan, R.; Heatwole, Conrad D. (Bogor, Indonesia: Bogor Agricultural University (IPB), 2008)
    Based on Proposal #9 of TMPEGS-Indonesia Year-3 (Y-3) Work Plan, the target in this period was the completion of the three main input components for SWAT analysis: Land Use, Soil and Slope Definition (WBS-300), and maintenance of ArcGIS 9.1 software license. These targets were almost completed except updated of ArcGIS 9.1 license which failed to be accomplished. Fortunately, the recent availability of open source package MapWindows-SWAT (MW-SWAT ver. 44SR), provided freely from www.waterbase.org by United Nations University (UNU), allowed the chance to complete early than expected all SWAT processing chain. Though it only used a low resolution global input data. SWAT-Indonesia now has the "advantage" to proceed with two options: Arc-SWAT or MW-SWAT. Accordingly, the scenario has been adapted to two-step approach: (1) a "quick yield" effort to complete SWAT chain process within Year-3 using MW-SWAT, and (2) an improved SWAT re-process in Year-4, to fine tuning the existing result with local input data (WBS-300) by applying MW-SWAT or Arc-SWAT option.
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    Impacts of reforestation policy and agro-forestry technology on the environment and food security in the Upper Tana river basin of Kenya
    Srinivasan, R.; Jacobs, J.; Stuth, Jerry; Angerer, Jay; Kaitho, R.; Clarke, N. (2004)
    This presentation is on a study to explore the hydrologic impacts on the Masinga reservoir in response to land use interventions in the Upper Tana River catchment with a focus on varying levels of reforestation.
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    Predicting effects of land use on runoff and sediment yield in selected sub-watersheds of the Manupali River using the ArcSWAT model
    Alibuyog, N. R.; Ella, Victor B.; Reyes, Manuel R.; Srinivasan, R.; Heatwole, Conrad D.; Dillaha, Theo A. III (2008)
    The quantitative prediction of environmental impacts of land-use changes in watersheds could serve as a basis for developing sound watershed management schemes, especially for Philippine watersheds with agroforestry systems. This study was conducted to determine the effects of various land-use patterns on runoff, and sediment yield in selected sub-watersheds of the Manupali River using the ArcSWAT model. ArcSWAT is a river basin scale model developed to quantify the impact of land management practices on water, sediment, and agricultural chemical yields in large, complex watersheds with varying soils, land use, and management conditions over long periods of time. In this study, the model was parameterized and calibrated in selected Manupali River sub-watersheds with an aggregate area of 2,177 ha to simulate the hydrologic effects of land use. Initial simulation results showed that conversion of forest to agricultural lands causes serious erosion and sediment yield in the area. Agricultural lands planted with corn, potato, and tomato, which make up 22.38 percent of the sub-watershed area, resulted in an average annual sediment yield of 110.1 t/ha, with the areas planted with potato producing the largest sediment yield of 205 t/ha. Forest and pasture and/or grassland produced a sediment yield of 0.7 t/ha and 2.15 t/ha, respectively. On average, simulation results showed an annual sediment yield of 12.86 t/ha for the whole area. It is evident from these initial results that conversion of forest to agricultural lands coupled with poor agricultural management practices could lead to serious erosion problems. Further simulation work will be done to generate results that could serve as sound basis for policy formulation geared toward sustainable watershed and agroforestry management.
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    Predicting the effects of land use on runoff and sediment yield in selected sub-watersheds of the Manupali River using the ArcSWAT model
    Alibuyog, N. R.; Ella, Victor B.; Reyes, Manuel R.; Srinivasan, R.; Heatwole, Conrad D.; Dillaha, Theo A. III (Bangkok, Thailand: World Association of Soil and Water Conservation, 2009)
    The quantitative prediction of environmental impacts of land use changes in watersheds could serve as basis for developing sound watershed management schemes, especially for Philippine watersheds with agroforestry systems. ArcSWAT, a river basin scale model developed to quantify the impact of land management practices on water, sediment, and agricultural chemical yields, was parameterized and calibrated in selected Manupali River sub-watersheds with an aggregate area of 200 ha to simulate the effects of land use on runoff volumes, sediment yield and streamflows.
  • Semi-annual reports: AVDRC organic farm
    Palada, Manuel C.; Luther, Gregory C.; Javier, E. C.; Srinivasan, R.; Engle, Liwayway M. (Greensboro, NC: North Carolina Agricultural and Technical State University, 2009)
    Executive Summary: Final field evaluation of vegetable species and varieties under agroforestry system continued at AVRDC Organic Farm. Five vegetables (Chinese cabbage, cucumber, eggplant, sweet pepper and tomato) were grown during the fall-winter season (October to December 2008) and winter-spring (January to March 2009) season. Vegetables were grown between tree hedgerows (alleys) and in control plots (no trees). Organic fertilizers (compost) were superimposed as sub-treatments. Varieties within vegetable species were compared in terms of growth and yield performance. Results from fall-winter cropping season have been summarized and presented in this report. The winter-spring trial is in progress and will be completed in April 2009.
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    SWAT implementation in Indonesia for vegetable agroforestry (VAF) systems: A progress report
    Raimadoya, M.; Reyes, Manuel R.; Srinivasan, R.; Heatwole, Conrad D. (2008)
    The overall goal is to convert degrading Southeast Asia watersheds into vibrant, sustainable basins enhancing quality of life for their inhabitants. To achieve this, the research has established as its first objective to develop an economically viable and ecologically sound integrated vegetable agroforestry (VAF) system to increase farm productivity and income through reliable supply of products and to reduce vulnerability and risks. The Soil and Water Assessment Tool (SWAT) has been selected as a basin scale model to assess the short- and long-term environmental impacts of the integrated VAF system.