%0 Journal Article
%T Spatial-temporal differences in in-stream flow requirement based on GIS:A case study of Yan''an region, northern Shaanxi<br>基于GIS的河流系统生态环境需水时空差异分析——以陕北延安地区为例
%A WANG Lixia
%A REN Zhiyuan
%A <br>王丽霞
%A 任志远
%J 地理学报(英文版)
%D 2008
%I 
%X Although water has the central function of the bloodstream in the biosphere especially in arid or semi-arid regions such as Yan’an region in northwestern China, yet the very limited attention is paid to the role of the water-related processes in ecosystem. In this re-search, based on continuous nearly 50-year data including runoff volume, sediment discharge as well as sediment accretion from hydrographic stations, and 10-year information of water quality from pollution monitoring stations, the method for measuring in-stream flow requirement has been put forward supported by experiential models and GIS spatial analysis. Additionally, the changes of in-stream flow requirement for environment and economic development have been addressed from spatial-temporal dimensions. The results show that: (1) According to the central streams in Yan’an region, mean annual in-stream flow requirement reaches 1.0619 billion m3, and the surface water for economic exploitation is 0.2445 billion m3. (2) Mean annual in-stream flow requirement for sediment transfers in flood period occupies over 80% of the integrated volume in a year. (3) From the 1950s to 1970s, in-stream flow requirement for sediment transfers is comparatively higher, while from the 1980s to 1990s, this requirement presents a decreasing tendency. Foundation: National Natural Science Foundation of China, No.40771019; Innovation Foundation of Shaanxi Normal University Author: Wang Lixia (1979–), Ph.D Candidate, specialized in water resources and GIS.
%K GIS spatial analysis
%K Yan’
%K an region
%K in-stream flow requirement
%K spatial-temporal differences<br>GIS
%K 河流系统
%K 生态环境
%K 时空差异分析
%K 延安地区
%U http://www.alljournals.cn/get_abstract_url.aspx?pcid=E62459D214FD64A3C8082E4ED1ABABED5711027BBBDDD35B&cid=869B153A4C6B5B85&jid=E7E6A89DD0CE36AA3756C02EB6F15CA7&aid=72C1E13C310AF14D6EB729ADA2C78236&yid=67289AFF6305E306&vid=13553B2D12F347E8&iid=CA4FD0336C81A37A&sid=D767283A3B658885&eid=DDD31293A7C7D057&journal_id=1009-637X&journal_name=地理学报(英文版)&referenced_num=0&reference_num=20