Quantitative assessments of the impacts of climate change and anthropogenic activities on runoff help us to better understand the mechanisms of hydrological processes.This study analyzed the dynamics of mountainous ru...Quantitative assessments of the impacts of climate change and anthropogenic activities on runoff help us to better understand the mechanisms of hydrological processes.This study analyzed the dynamics of mountainous runoff in the upper reaches of the Shiyang River Basin(USRB)and its sub-catchments,and quantified the impacts of climate change and human activities on runoff using the improved double mass curve(IDMC)method,which comprehensively considers the effects of precipitation and evapotranspiration on runoff,instead of only considering precipitation as before.The results indicated that the annual runoff depth in the USRB showed a slightly increased trend from 1961 to 2018,and sub-catchments were increased in the west and decreased in the east.The seasonal distribution pattern of runoff depth in the USRB and its eight sub-catchments all showed the largest in summer,followed by autumn and spring,and the smallest in winter with an increasing trend.Quantitative assessment results using the IDMC method showed that the runoff change in the USRB is more significantly affected by climate change,however,considerable differences are evident in sub-catchments.This study further developed and improved the method of runoff attribution analysis conducted at watershed scale,and these results will contribute to the ecological protection and sustainable utilization of water resources in the USRB and similar regions.展开更多
The study employs slope, aspect, relief degree of land surface, land use, vegetation index, hydrology and climate, as evaluation indexes to set up the Human Settlements Environmental Index （HEI） model to evaluate th...The study employs slope, aspect, relief degree of land surface, land use, vegetation index, hydrology and climate, as evaluation indexes to set up the Human Settlements Environmental Index （HEI） model to evaluate the environmental suitability for human settlements in the Shiyang River Basin. By using GIS spatial analysis technology, such as spatial overlay analysis, buffer analysis and density analysis, the environmental suitability of the human set- tlement spatial situation and spatial pattern are established to analyze their spatial distribution The results show that the index of suitability for human settlements in the Shiyang River Basin is between 17.13 and 84.32. In general, suitability for human settlements decreases from the southwest to the northeast. Seen from an area pattern, the suitable region is mainly distributed in the Minqin oasis, Wuwei oasis and Changning basin, which are about 1080.01 km2 and account for 2.59% of the total area. Rather and comparatively suitable region is mainly distributed around the counties of Gulang, Yongchang and north of Tianzhu, which is about 1100.30 km2. The common suitable region is mainly distributed outside the counties of Yongchang, Jinchuan and most parts of Minqin County, which are about 23328.04 km2, accounting for 56.08% of the total area. The unsuitable region is mainly distributed upstream and to the north of the river, which is about 9937.60 km2, accounting for 23.89% of the total area. Meanwhile, the least suitable region is distributed around the Qilian Mountains, which are covered by snow and cold desert and lie in the intersecting area between the Tengger Desert and Badain Jaran Desert. The total area is about 6154.05 km2, accounting for 14.79% of the total area. Suitable regions for human habitation are mainly distributed around rivers in the form of ribbons and batches, while others are scattered. The distribution pattern is iden- tical to the residential spatial pattern. In addition, the relationships between HEI and other factors have been analyzed. There is a clear logarithmic correlation between the residential environment and population, that is, the correlation coefficient between the evaluation valueand population density reaches 0.851. There is also a positive correlation between the residential environment and economy, which reaches an evaluation value of 0.845 between the residential environment and GDP. Results also show that the environment is out of bearing with the existing population in Shiyang River Basin. Spatial distribution of population is pro- foundly affected by severe environmental problems, such as the expanded deserts, the hilly terrain and the changing climate. Surface water shortage and slow economic growth are bot- tlenecks for suitable human settlement in the Shiyang River Basin. Combining these prob- lems with planning for construction of new country and the exploitation of local land, some residential areas should be relocated to improve the residential environment.展开更多
基金National Natural Science Foundation of China,No.42361005,No.41861034,No.41661040,No.32060373。
文摘Quantitative assessments of the impacts of climate change and anthropogenic activities on runoff help us to better understand the mechanisms of hydrological processes.This study analyzed the dynamics of mountainous runoff in the upper reaches of the Shiyang River Basin(USRB)and its sub-catchments,and quantified the impacts of climate change and human activities on runoff using the improved double mass curve(IDMC)method,which comprehensively considers the effects of precipitation and evapotranspiration on runoff,instead of only considering precipitation as before.The results indicated that the annual runoff depth in the USRB showed a slightly increased trend from 1961 to 2018,and sub-catchments were increased in the west and decreased in the east.The seasonal distribution pattern of runoff depth in the USRB and its eight sub-catchments all showed the largest in summer,followed by autumn and spring,and the smallest in winter with an increasing trend.Quantitative assessment results using the IDMC method showed that the runoff change in the USRB is more significantly affected by climate change,however,considerable differences are evident in sub-catchments.This study further developed and improved the method of runoff attribution analysis conducted at watershed scale,and these results will contribute to the ecological protection and sustainable utilization of water resources in the USRB and similar regions.
基金National Natural Science Foundation of China, No.41261104 No.40971078+1 种基金 National Social Science Foundation Youth Project of China, No.12CTJ001 Youth Fund Projects of Science and Technology from Gansu Province, No.1107RJYA077
文摘The study employs slope, aspect, relief degree of land surface, land use, vegetation index, hydrology and climate, as evaluation indexes to set up the Human Settlements Environmental Index （HEI） model to evaluate the environmental suitability for human settlements in the Shiyang River Basin. By using GIS spatial analysis technology, such as spatial overlay analysis, buffer analysis and density analysis, the environmental suitability of the human set- tlement spatial situation and spatial pattern are established to analyze their spatial distribution The results show that the index of suitability for human settlements in the Shiyang River Basin is between 17.13 and 84.32. In general, suitability for human settlements decreases from the southwest to the northeast. Seen from an area pattern, the suitable region is mainly distributed in the Minqin oasis, Wuwei oasis and Changning basin, which are about 1080.01 km2 and account for 2.59% of the total area. Rather and comparatively suitable region is mainly distributed around the counties of Gulang, Yongchang and north of Tianzhu, which is about 1100.30 km2. The common suitable region is mainly distributed outside the counties of Yongchang, Jinchuan and most parts of Minqin County, which are about 23328.04 km2, accounting for 56.08% of the total area. The unsuitable region is mainly distributed upstream and to the north of the river, which is about 9937.60 km2, accounting for 23.89% of the total area. Meanwhile, the least suitable region is distributed around the Qilian Mountains, which are covered by snow and cold desert and lie in the intersecting area between the Tengger Desert and Badain Jaran Desert. The total area is about 6154.05 km2, accounting for 14.79% of the total area. Suitable regions for human habitation are mainly distributed around rivers in the form of ribbons and batches, while others are scattered. The distribution pattern is iden- tical to the residential spatial pattern. In addition, the relationships between HEI and other factors have been analyzed. There is a clear logarithmic correlation between the residential environment and population, that is, the correlation coefficient between the evaluation valueand population density reaches 0.851. There is also a positive correlation between the residential environment and economy, which reaches an evaluation value of 0.845 between the residential environment and GDP. Results also show that the environment is out of bearing with the existing population in Shiyang River Basin. Spatial distribution of population is pro- foundly affected by severe environmental problems, such as the expanded deserts, the hilly terrain and the changing climate. Surface water shortage and slow economic growth are bot- tlenecks for suitable human settlement in the Shiyang River Basin. Combining these prob- lems with planning for construction of new country and the exploitation of local land, some residential areas should be relocated to improve the residential environment.
