干旱区研究2024，Vol.41Issue(11)：1819-1830,12.DOI:10.13866/j.azr.2024.11.03
基于改进S-W模型的南小河沟流域蒸散发分配及控制机制
Research on the distribution and control mechanism of evapotranspiration in the Nanxiaohegou watershed based on an improved S-W model
摘要
Abstract
In this study,we aimed to accurately quantify evapotranspiration(ET)and its components while explor-ing the factors that control it,which will facilitate the practical evaluation,planning,and management of regional water resources.Utilizing continuous long-term observation data and field tests conducted from 2016 to 2020 in the Nanxiaohegou watershed—a typical small watershed for water and soil conservation on the Loess Plateau—this study simulated the dynamic changes of ET and its components in typical plantation land using the improved Shuttleworth-Wallace(S-W)model.Additionally,we analyzed the coupling relationships between plant transpira-tion(T),soil evaporation(E),and control factors using a structural equation model.The results revealed the fol-lowing:(1)The modified S-W model was effective for evaluating ET and its components in Nanxiaohe Valley.The threshold value of soil surface resistance(rss)was 50-2500 s·m-1,exhibiting an exponential relationship with the empirical function of soil surface water content(θ);moreover,higher sand content in the soil particles correlated with a steeper linear slope.(2)ET ranged from 276.76 mm to 402.86 mm in typical plantation land,with annual averages of Tand E accounting for 51.6%and 48.4%of ET,respectively.While monthly ET,T,and E patterns were not pronounced,daily fluctuations were significant.The fluctuation trends of T and E largely reflect-ed annual precipitation patterns but lagged behind rainfall.(3)Structural equation modeling analysis revealed that net radiation(Rn),temperature(Ta),and θ exerted the most significant effects on ET,with Rn having the largest im-pact on T(total impact of 0.614)and Ta having the most significant impact on E(total impact of 0.426).Twas pos-itively correlated with E,with a contribution coefficient of 0.503.Evaluating ET and its components using an im-proved S-W model establishes a foundation for a deeper understanding of ecological and hydrological processes in arid and semiarid regions.关键词
蒸散发组分/改进S-W模型/SEM模型/蒸发抗阻力/南小河沟流域Key words
evaporative components/improve the S-W model/SEM model/evaporation resistance/Nanxiaohe-gou watershed引用本文复制引用
杨楠,丁林,李浩霖,宋孝玉,邓建伟,李蓝君,赵新凯,孟鹏飞,符冲,魏婉茵,张育斌..基于改进S-W模型的南小河沟流域蒸散发分配及控制机制[J].干旱区研究,2024,41(11):1819-1830,12.基金项目
甘肃省重点研发计划项目(22YF7FA081) （22YF7FA081）
陕西省自然科学基础研究计划项目(2023-JC-ZD-30,2019JZ-45) （2023-JC-ZD-30,2019JZ-45）
甘肃省水利科研与技术推广计划项目(24GSLK007,23GSLK012,23GSLK013) （24GSLK007,23GSLK012,23GSLK013）
