%0 Journal Article %A WANG Lixia %A REN Zhiyuan %T Spatial-temporal differences in in-stream flow requirement based on GIS: A case study of Yan’an region, northern Shaanxi %D 2008 %R 10.1007/s11442-008-0107-4 %J Journal of Geographical Sciences %P 107-114 %V 18 %N 1 %X

Although water has the central function of the bloodstream in the biosphere espe-cially 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 require-ment has been put forward supported by experiential models and GIS spatial analysis. Addi-tionally, the changes of in-stream flow requirement for environment and economic develop-ment 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.

%U https://www.geogsci.com/EN/10.1007/s11442-008-0107-4