Modeling hydrologic responses using multi-site and single-site rainfall generators in a semi-arid watershed  

作　　者：Ying Zhao Mark A.Nearing David Phillip Guertin 

机构地区：[1]State Key Laboratory of Simulation and Regulation of the Water Cycle in River Basins,China Institute of Water Resources and Hydropower Research,Beijing,100048,China [2]USDA-Agricultural Research Service,Southwest Watershed Research Center,Tucson,AZ,85719,USA [3]School of Natural Resources and the Environment,University of Arizona,Tucson,AZ,85719,USA

出　　处：《International Soil and Water Conservation Research》2022年第2期177-187,共11页国际水土保持研究（英文）

基　　金：Specific Cooperative Agreement between the USDA Agricultural Research Service(Agreement number 58-53424-018);the University of Arizona(Agreement number 2022-13610-012-22S);the Independent research project of State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin(Grant No.SKL2020TS10);the Research&Development Support Program of China Institute of Water Resources and Hydropower Research(grant number SC0145B012021).

摘　　要：Hydrologic response in a watershed is driven by precipitation.Multi-site rainfall generators can be used to model watersheds using spatially varied rainfall inputs to better analyze how the rainfall variability affects runoff generation.This study adopted both a single-site rainfall generator(CLIGEN)and a multi-site rainfall generator to generate two rainfall data sequences,which were then used to drive the Soil and Water Assessment Tool(SWAT)for runoff simulation.The 148-km2 Walnut Gulch Experimental Watershed and its two sub-watersheds were selected to evaluate the hydrologic response.Runoff calibration was done against measured runoff in the watershed.Statistics showed that the single-site and multi-site rainfall generators gave similar results regarding annual precipitation.However,the multi-site generator performed much better than the single-site generator in both mean summer flow and for the different return period flows.The runoff derived from the single-site generator was significantly over-estimated in all three watersheds.As for the multi-site generator,the derived runoff was satisfactorily predicted in the smaller watersheds but only overestimated in the largest watershed.This indicated that in small to medium sized watersheds,the spatial variability of rainfall could play an important role for hydrologic response because of the heterogeneity of convective rainfall in this semi-arid region,which makes the application of multi-site rainfall generator a better option than the single-site generator.

关 键 词：Rainfall generator Hydrologic response Watershed modeling SEMI-ARID Spatial variability RUNOFF 

分 类 号：S157[农业科学—土壤学]