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Watershed Planning within a Quantitative Scenario Analysis Framework
Published on: July 24, 2016
Parameter uncertainty analysis of non-point source pollution from different land use types.
Zhen-yao Shen1, Qian Hong, Hong Yu
1State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, P.R. China. z.y.shen@163.com
The Science of the Total Environment
|December 29, 2009
Summary
Land use impacts non-point source (NPS) pollution simulation uncertainty. Different land types like forest, grassland, and plantation show varying parameter uncertainties, influencing runoff, sediment, nitrogen, and phosphorus levels.
Area of Science:
- Environmental Science
- Hydrology
- Water Quality Modeling
Background:
- Non-point source (NPS) pollution significantly impacts water bodies, with land use type being a key driver of simulation uncertainty.
- Accurate modeling of NPS pollution is crucial for effective watershed management, especially in sensitive areas like the Three Gorges Reservoir.
Purpose of the Study:
- To analyze parameter uncertainty in the Soil and Water Assessment Tool (SWAT) model across different land use types.
- To investigate how land use variations (plantation, forest, grassland) affect model output uncertainty for runoff, sediment, organic nitrogen, and total phosphorus.
Main Methods:
- Screening of seventeen sensitive parameters within the SWAT model.
- Application of the First-Order Error Analysis (FOEA) method to quantify parameter uncertainty effects.
- Comparative analysis across plantation, forest, and grassland land use scenarios in the Daning River Watershed.
Main Results:
- Parameter uncertainty varied significantly among the three land use types.
- In forest and grassland, uncertainty was mainly linked to runoff processes.
- In plantations, uncertainty was associated with both runoff processes and soil properties.
Conclusions:
- Land use type is a critical factor influencing NPS pollution simulation uncertainty.
- Strategies to control NPS pollution in the Daning River Watershed should include optimizing land use structure and managing fertilizer application.
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