A Modified Distributed CN-VSA Method for Mapping of the Seasonally Variable Source Areas
| Autor: | Ramesh Rudra, Pradeep K. Goel, Kishore Panjabi, Bahram Gharabaghi, Syed I. Ahmed |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2021 |
| Předmět: |
Topographic Wetness Index
Watershed variable source area 010504 meteorology & atmospheric sciences Geography Planning and Development 0207 environmental engineering 02 engineering and technology Aquatic Science Runoff curve number 01 natural sciences Biochemistry Water balance topographic wetness index 020701 environmental engineering Water content TD201-500 Nonpoint source pollution 0105 earth and related environmental sciences Water Science and Technology Hydrology Water supply for domestic and industrial purposes Hydraulic engineering SCS-CN saturation excess runoff non-point-source pollution Environmental science Surface runoff Soil conservation TC1-978 |
| Zdroj: | Water, Vol 13, Iss 1270, p 1270 (2021) Water Volume 13 Issue 9 |
| ISSN: | 2073-4441 |
| Popis: | Many watershed models employ the Soil Conservation Service Curve Number (SCS-CN) approach for runoff simulation based on soil and land use information. These models implicitly assume that runoff is generated by the Hortonian process and therefore, cannot correctly account for the effects of topography, variable source area (VSA) and/or soil moisture distribution in a watershed. This paper presents a new distributed CN-VSA method that is based on the SCS-CN approach to estimate runoff amount and uses the topographic wetness index (TWI) to distribute the runoff-generating areas within the watershed spatially. The size of the saturated-watershed areas and their spatial locations are simulated by assuming an average annual value of potential maximum retention. However, the literature indicates significant seasonal variation in potential maximum retention which can considerably effect water balance and amount of nonpoint source pollution. This paper focuses on developing a modified distributed CN-VSA method that accounts for the seasonal changes in the potential maximum retention. The results indicate that the modified distributed CN-VSA approach is better than distributed CN-VSA to simulate runoff amount and spatial distribution of runoff-generating areas. Overall, the study results are significant for improved understanding of hydrological response of watershed where seasonal factors describe the potential maximum retention, and, thus, saturation excess runoff generation in the watershed. |
| Databáze: | OpenAIRE |
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