Christopher L. Shope, Svenja Bartsch, Marianne Ruidisch, Sebastian Arnhold 6 August International SWAT Conference Ilsan, South Korea

Transcription

1 Tractors, Rice, and Mountains: Hydrogeochemistry in Monsoonal South Korea Christopher L. Shope, Svenja Bartsch, Marianne Ruidisch, Sebastian Arnhold 6 August International SWAT Conference Ilsan, South Korea Jae-E Yang, 2006

2 Haean Study Area Location

3 Shope Presentation Outline Why this study is necessary General project approach and interests Local field projects and decision making Conceptual, numerical, and distributed models of the catchment Some early results Where do we go from here?

4 Major Research Problems High phosphorous and nitrate concentrations in agricultural setting Very steep, mountainous, and forested slopes Monsoonal erosion of the landscape during peak flow events, particularly encroached areas. High sediment transport increasing TSS and P Increase of erosion over time tractors vs sediment Different crop management techniques like rice Very strong agricultural lobby

5 Bridging Science within TERRECO Complex Terrain and Ecological Heterogeneity (TERRECO) Landscape Processes Atmospheric coupling Plant production Biogeochemistry Hydrology and transport ANALYSIS AND MODELING Social Framework Demography Regulatory policy Economic analysis Land management Land use decisions CLIMATE CHANGE SOCIAL-ECOLOGICAL SCENARIO EVALUATIONS SOCIAL RESPONSE DESIRED ECOSYSTEM SERVICES AGENCY DISCOURSE Land use decisions SUSTAINABLE ECOSYSTEM SERVICES SCALING with respect to GLOBAL CHANGE ISSUES POLICY ACROSS SCALES Tenhunen et. al., 2010

6 Local Field Studies for Modeling Effort Yearly change in land use and local decisions. Climate conditions on carbon uptake and crops Fertilizer input and agricultural efficiency Insects, pests, birds and new biological controls Soil structure and biogeochemical responses. Water quality and quantity and material transport Local stakeholder interests and decisions

7 Conceptual Haean Catchment Geology Metamorphic Uplands Alluvium Granitic Intrusion and Stress Faults / Fractures Metamorphic Uplands

8 Some Focused and Project-Wide Models EROSION 3-D HydroGeoSphere TOPMODEL PIXGRO SWAT-2005 HBV-Light

9 Haean Catchment Topography

10 Land Use / Crop Identification Forest-Evergreen Rice Range-Grasses Potato Sugarcane Forest-Deciduous Southwestern US (Arid) Range Green Beans Cabbage Alfalfa Orchard Tobacco Corn Transportation Residential-Low Density Cantaloupe Agricultural Land-Generic Commercial Bell Pepper Institutional Alamo Switchgrass Land Use / Crop Type Percentage Forest- Evergreen 56% Rice 14%

11 Surficial Soil Distribution HINCKLEY HUBBARDTON BOMOSEEN AMENIA LAMOINE TIOGA SHELBURNE HERO SACO GALWAY PINNEBOG COLRAIN GLOVER TUNBRIDGE PITTSTOWN BUXTON MERRIMAC GEORGIA FREDON STOWE KILLINGTON Soil Distribution Percentage BOMOSEEN 12% HUBBARDTON 16% AMENIA 11% HINCKLEY 21% LAMOINE 8% TIOGA 5%

12 Topographic Slope Classification Topographic Gradient Percentage % 59% Haean Catchment Topographic Elevation Cummulative Percentage in Watershed % Ground Surface Elevation (m) Elevation Gradient

13 Soil and Water Assessment Tool SWAT2005 Source DEM Delineation Land Use Soil Type Calibration/ Validation RESULTS Flow, Sediment, Water Quality meteorology, WQ, nutrient conc., pesticides, plant growth, fertilizers, tillage, management, etc. Full HRU Slope Classes

14 Major Sediment Input in Soyang Watershed Sediment Load Location (ton ha -1 ) Gau-ri 55.3 Haean-Myun 39.2 Jaun-ri 23.6 Gwang-Sam Kim, 2010

15 Surface Water Quality Responses

16 Groundwater Water Quality dry land farming (corn, winery) river rice paddies W m W m W m W m ca. 140 m aquifer

17 Conclusions Lots of rain focused over a few months. Values of over 80 mm /hr, 250 mm/event not abnormal. Heavy and increasing agriculture on steep slopes Increasing sediment and phosphorous entering the surface water. High nitrate in groundwater, even on upper slopes. Regulatory requirements are not consistent Will farming practices change? If so, how do they change and who benefits?

18 Questions?