Study On Eco-environment Water Requirement In East Liaohe River Basin Of Jilin Province

Water resource is the most important elements of the ecological environment andthe indispensable condition of human existence and social development.Eco-environment water is significant factor to protect and maintain the normaloperation of the water environment. Liaohe river basin has been faced with a series ofecological and environment problems, including water shortages, unbalanced waterallocation and heavy pollution. It was with significant meaning to carry out theresearch about eco-environment water requirement in east Liaohe river basin of Jilinprovince and sustainable development of watershed ecosystems. This research reliedon a major national water projects, and eco-environment water requirement of eastLiaohe River Basin were calculated and analysed.This paper discusses the theory and technical methods of eco-environment waterrequirement. It summarizes the classification of eco-environment water requirement.It includes inner river eco-environment water requirement and outer eco-environmentwater requirement. The inner river eco-environment water requirement includes basedon ecological flow, self-purification of water requirement, purification of waterrequirement, sediment transportation of water requirement, evaporation of waterrequirement and leakage of water requirement. The outer river eco-environment waterrequirement includes eco-environment water requirement of lake, eco-environmentwater requirement of vegetation and eco-environment water requirement of city.The inner river eco-environment water requirement was calculated by Tennantmethod and the most dry month flow method of east Liaohe, Zhaosutai river andTiaozi river. The results were2.416×10~8m~3,0.12×10~8m~3and0.026×10~8m~3. Theminimum eco-environment water requirement were calculated by the minimum waterlevel method of Erlongshan reservoir, Shangshantai reservoir and Xiashantai reservoir.The results were2.75×10~8m~3、0.03×10~8m~3and0.07×10~8m~3. The satellite remotesensing images were interpreted by ArcGIS of2000and2008. It analyzed the landuse change. The eco-environment water requirement of vegetation was calculated byquota-area method and diving evaporation method. The outer river eco-environment water requirement was65.53×10~8m~3and62.06×10~8m~3. The eco-environment waterrequirement was68.09×10~8m~3and64.62×10~8m~3in2000and2008. It divided andcalculated the buffer eco-environment water requirement of both sides of the riverbank1km and2km. The buffer eco-environment water requirement was14.47×10~8m~3and22.89×10~8m~3in2000. The buffer eco-environment water requirement was12.39×10~8m~3and19.10×10~8m~3in2008. The eco-environment water requirement wasreduced due to the paddy field area was reduced a lot.The water resource of east Liaohe River was lack of0.183×10~8m~3. TheHydrological station showed a trend of shortage of ecological water within a decade.The water resource was lack of7.84×10~8m~3in2000. The water resource was plentifulin2008. The biggest impact on the eco-environment water requirement from thechange in paddy field. The decrease in paddy fields to ease the water shortagesituation. Variation of paddy and grassland had the positive effect on total ecologicalwater requirement, and variation of farmland and forest land had the negative effect.The result provided scientific basis for the rational planning of water resources andland use change of east Liaohe river basin of Jilin province.