Accurately identifying the spatial differences in the response of regional runoff to climate and land use changes can clarify the mechanism of regional runoff changes and provide a scientific basis for adopting the ap...Accurately identifying the spatial differences in the response of regional runoff to climate and land use changes can clarify the mechanism of regional runoff changes and provide a scientific basis for adopting the appropriate water resource protection policies.In this study,based on the Budyko theory,we quantitatively evaluated the spatial differences in the response of runoff to climate and land use changes in the Yiluo River Basin after 2000;calculated the sensitivity of runoff changes to precipitation(P),potential evapotranspiration(E_(0))and land use changes;and quantified the contributions of those three factors to runoff changes.The findings revealed that with decreasing elevation,precipitation gradually decreases,potential evapotranspiration gradually increases,and runoff gradually decreases in the Yiluo River basin.Influenced by the population density,both cultivated land and construction land are widely distributed with the middle and lower reaches of the basin,while the upper reaches are dominated by forest land.Compared with the base period(1985-1989),precipitation and potential evapotranspiration in the watershed during the change period(2000-2017)basically showed decreasing and increasing trends,respectively,with obvious spatial differentiation.P increased significantly in the upper reaches of the Yi River,with an average of 35.2 mm(-83.8-84.7 mm),while P increased and decreased in the other five subbasins,but the decreasing trend was more prominent.Among the subbasins,the upper and middle reaches of the Luo River showed the largest reductions in P,with an average of-34.2 mm(-145.9-20.6 mm),whereas the middle reaches of the Yi River showed the smallest reduction in P,with an average of-10.9 mm(-84.2-59.5 mm).The E_(0)in the different regions during the change period showed an increasing trend,and the increase in E_(0)gradually decreased from the upper reaches to the lower reaches.The E_(0)in the upper reaches of the Luo River showed the largest change,with an average of 45.3 mm(38.2-48.3 mm),while the lower reaches of the Yiluo River showed the smallest change,with an average of 7.3 mm(-3.2-17.1 mm).Land use changes were primarily from cultivated to construction land in the middle and lower reaches.Runoff changes were positively correlated with precipitation changes and negatively correlated with potential evapotranspiration and land use changes.The absolute values of the sensitivity coefficients of runoff to these environmental factors decreased with lower altitude,indicating a reduced responsiveness of the basin runoff under a warming and drying climate trend.Reductions in precipitation and changes in potential evapotranspiration have led to reductions in runoff ranging from 4.7 to 17.4 mm and from 0.7 to 9.1 mm,respectively,while land use changes led to corresponding runoff reductions of 23.0 to 46.5 mm,suggesting that land use changes are more likely to trigger runoff changes in the basin than climatic fluctuations.Given the dominance of cultivated land,especially in the middle and lower reaches,and the region’s high susceptibility to human activities,there has been a significant reduction in runoff in recent years.The contribution of land use change to the runoff reduction in the Yiluo River Basin was greater at lower elevations,up to 86.1%,while climatic effects were more significant at higher elevations,up to 27.8%.Therefore,promoting the implementation of projects such as water ecological restoration and returning farmland to forests are of great significance to curb the over-exploitation of groundwater,to formulate scientific management and scheduling policies in order to realize the transformation of the water balance in the river basin from a non-steady state to a steady state,and to promote the integrity of the ecosystem of the lower reaches of the Yellow River and ensure its sustainable development.展开更多
【目的】伊洛河流域属于国家级水土流失重点治理区,研究伊洛河流域的土壤保持功能对科学认识伊洛河流域土壤侵蚀特征、防治土地退化等具有重要意义。【方法】研究基于伊洛河流域1990年与2020年降雨侵蚀力因子、坡度坡长因子、植被、土...【目的】伊洛河流域属于国家级水土流失重点治理区,研究伊洛河流域的土壤保持功能对科学认识伊洛河流域土壤侵蚀特征、防治土地退化等具有重要意义。【方法】研究基于伊洛河流域1990年与2020年降雨侵蚀力因子、坡度坡长因子、植被、土壤等数据,利用InVEST模型,估算伊洛河流域土壤侵蚀量和土壤保持量,从流域尺度与县域尺度分析了伊洛河流域土壤侵蚀量和土壤保持量的时空格局。【结果】研究结果显示,1990年和2020年实际土壤侵蚀强度主要处于强烈侵蚀(50~80 t hm^(-2))、极强烈侵蚀(80~150 t hm^(-2))等级,此两类约占流域面积的50%,其中高值区主要分布在坡度较大的西部低山丘陵区。未利用地、建设用地、耕地地类的平均土壤侵蚀量较高。【结论】与1990年相比,2020年各地类平均土壤侵蚀强度有所下降。1990年与2020年土壤保持能力较高的区域主要分布在西部低山丘陵区,低值主要分布在东部地形平坦、经济发展较好的地区。与1990年相比,2020年伊洛河流域土壤保持能力呈降低趋势。研究结论可深化对伊洛河流域土壤侵蚀特征的科学认识,为编制水土保持规划,防治土地退化等提供参考。展开更多
基金The National Natural Science Foundation of China(52130907)。
文摘Accurately identifying the spatial differences in the response of regional runoff to climate and land use changes can clarify the mechanism of regional runoff changes and provide a scientific basis for adopting the appropriate water resource protection policies.In this study,based on the Budyko theory,we quantitatively evaluated the spatial differences in the response of runoff to climate and land use changes in the Yiluo River Basin after 2000;calculated the sensitivity of runoff changes to precipitation(P),potential evapotranspiration(E_(0))and land use changes;and quantified the contributions of those three factors to runoff changes.The findings revealed that with decreasing elevation,precipitation gradually decreases,potential evapotranspiration gradually increases,and runoff gradually decreases in the Yiluo River basin.Influenced by the population density,both cultivated land and construction land are widely distributed with the middle and lower reaches of the basin,while the upper reaches are dominated by forest land.Compared with the base period(1985-1989),precipitation and potential evapotranspiration in the watershed during the change period(2000-2017)basically showed decreasing and increasing trends,respectively,with obvious spatial differentiation.P increased significantly in the upper reaches of the Yi River,with an average of 35.2 mm(-83.8-84.7 mm),while P increased and decreased in the other five subbasins,but the decreasing trend was more prominent.Among the subbasins,the upper and middle reaches of the Luo River showed the largest reductions in P,with an average of-34.2 mm(-145.9-20.6 mm),whereas the middle reaches of the Yi River showed the smallest reduction in P,with an average of-10.9 mm(-84.2-59.5 mm).The E_(0)in the different regions during the change period showed an increasing trend,and the increase in E_(0)gradually decreased from the upper reaches to the lower reaches.The E_(0)in the upper reaches of the Luo River showed the largest change,with an average of 45.3 mm(38.2-48.3 mm),while the lower reaches of the Yiluo River showed the smallest change,with an average of 7.3 mm(-3.2-17.1 mm).Land use changes were primarily from cultivated to construction land in the middle and lower reaches.Runoff changes were positively correlated with precipitation changes and negatively correlated with potential evapotranspiration and land use changes.The absolute values of the sensitivity coefficients of runoff to these environmental factors decreased with lower altitude,indicating a reduced responsiveness of the basin runoff under a warming and drying climate trend.Reductions in precipitation and changes in potential evapotranspiration have led to reductions in runoff ranging from 4.7 to 17.4 mm and from 0.7 to 9.1 mm,respectively,while land use changes led to corresponding runoff reductions of 23.0 to 46.5 mm,suggesting that land use changes are more likely to trigger runoff changes in the basin than climatic fluctuations.Given the dominance of cultivated land,especially in the middle and lower reaches,and the region’s high susceptibility to human activities,there has been a significant reduction in runoff in recent years.The contribution of land use change to the runoff reduction in the Yiluo River Basin was greater at lower elevations,up to 86.1%,while climatic effects were more significant at higher elevations,up to 27.8%.Therefore,promoting the implementation of projects such as water ecological restoration and returning farmland to forests are of great significance to curb the over-exploitation of groundwater,to formulate scientific management and scheduling policies in order to realize the transformation of the water balance in the river basin from a non-steady state to a steady state,and to promote the integrity of the ecosystem of the lower reaches of the Yellow River and ensure its sustainable development.
文摘【目的】伊洛河流域属于国家级水土流失重点治理区,研究伊洛河流域的土壤保持功能对科学认识伊洛河流域土壤侵蚀特征、防治土地退化等具有重要意义。【方法】研究基于伊洛河流域1990年与2020年降雨侵蚀力因子、坡度坡长因子、植被、土壤等数据,利用InVEST模型,估算伊洛河流域土壤侵蚀量和土壤保持量,从流域尺度与县域尺度分析了伊洛河流域土壤侵蚀量和土壤保持量的时空格局。【结果】研究结果显示,1990年和2020年实际土壤侵蚀强度主要处于强烈侵蚀(50~80 t hm^(-2))、极强烈侵蚀(80~150 t hm^(-2))等级,此两类约占流域面积的50%,其中高值区主要分布在坡度较大的西部低山丘陵区。未利用地、建设用地、耕地地类的平均土壤侵蚀量较高。【结论】与1990年相比,2020年各地类平均土壤侵蚀强度有所下降。1990年与2020年土壤保持能力较高的区域主要分布在西部低山丘陵区,低值主要分布在东部地形平坦、经济发展较好的地区。与1990年相比,2020年伊洛河流域土壤保持能力呈降低趋势。研究结论可深化对伊洛河流域土壤侵蚀特征的科学认识,为编制水土保持规划,防治土地退化等提供参考。
