title: Hydrological Responses to Land-Use Change Scenarios under Constant and Changed Climatic Conditions.
abstract: This study quantified the hydrological responses to land-use change scenarios in the upper and middle Heihe River basin (HRB), northwest China, under constant and changed climatic conditions by combining a land-use/cover change model (dynamic conversion of land use and its effects, Dyna-CLUE) and a hydrological model (soil and water assessment tool, SWAT). Five land-use change scenarios, i.e., historical trend (HT), ecological protection (EP), strict ecological protection (SEP), economic development (ED), and rapid economic development (RED) scenarios, were established. Under constant climatic condition, hydrological variations are only induced by land-use changes in different scenarios. The changes in mean streamflow at the outlets of the upper and the middle HRB are not pronounced, although the different scenarios produce different outcomes. However, more pronounced changes are observed on a subbasin level. The frequency of extreme flood is projected to decrease under the SEP scenario, while under the other scenarios, no changes can be found. Two emission scenarios (A1B and B1) of three general circulation models (HadCM3, CGCM3, and CCSM3) were employed to generate future possible climatic conditions. Under changed climatic condition, hydrological variations are induced by the combination of land-use and climatic changes. The results indicate that the impacts of land-use changes become secondary when the changed climatic conditions have been considered. The frequencies of extreme flood and drought are projected to decrease and increase, respectively, under all climate scenarios. Although some agreements can be reached, pronounced difference of hydrological responses can be observed for different climate scenarios of different GCMs.
authors.affiliation: Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou, 730000, People's Republic of China.|University of Chinese Academy of Sciences, Beijing, 100049, People's Republic of China.
authors.forename: Ling
authors.initials: L
authors.lastname: Zhang
authors.affiliation: School of Geography Science, Nanjing Normal University, Nanjing, 210023, People's Republic of China. nanzt@njnu.edu.cn.|Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing, 210023, People's Republic of China. nanzt@njnu.edu.cn.
authors.forename: Zhuotong
authors.initials: Z
authors.lastname: Nan
authors.affiliation: Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou, 730000, People's Republic of China.
authors.forename: Wenjun
authors.initials: W
authors.lastname: Yu
authors.affiliation: Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou, 730000, People's Republic of China.
authors.forename: Yingchun
authors.initials: Y
authors.lastname: Ge
mesh_terms: D002681:China; D002980:Climate; D057231:Climate Change; D003247:Conservation of Natural Resources; D017753:Ecosystem; D055868:Floods; D062070:Hydrology; D008962:Models, Theoretical; D045483:Rivers; D012987:Soil; D014872:Water Movements
chemical_list: D012987:Soil
keywords: Climate change; Dyna-CLUE; Heihe River basin; Hydrological response; Land-use change; SWAT