Renmin Zhujiang (Jan 2022)
Assessment of Cumulative Impacts of Climate Change and Land Use Change on Runoff Variations in Source Area of Yellow River
Abstract
The attribution of runoff variations is a key scientific issue for the understanding of the hydrological cycle.The traditional Budyko framework focuses on the comparison of two periods and lacks a description of the cumulative effects of influencing factors.Taking the key hydrological stations in the source area of the Yellow River as an example,this study adopts the Budyko framework based on time-varying parameters to analyze the cumulative impacts of climate change and land use change on runoff variations in the source area from 1960 to 2016 and reveal the internal mechanism of runoff variations.The results indicate that there is no significant change in the annual runoff of the Jimai Station in the source area of the Yellow River,but the annual runoff of Maqu and Tangnaihai Stations decreases significantly.The impacts of climate change on runoff for the three stations fluctuate over time:Due to climate change,the runoff increases from 1973 to 1990 and after 2004 but decreases from 1991 to 2003,with the cumulative impact value of climate change reaching its maximum in 1990 (above 15 mm) and its minimum in 2003 (-10.85 mm,-20.91 mm,and -21.66 mm for the above three stations,respectively).Except for some periods of the Jimai Station,the runoff is all reduced due to land use change,and the final values of the cumulative impact of land use change on the three stations are -9.17 mm,-32.09 mm,and -31.65 mm,respectively.Climate change plays an important role in runoff variations at the Jimai Station,while land use change has a greater cumulative impact on Maqu and Tangnaihai Stations.
