Study On Eco-environment Water Requirement And Water Compensation In Yitong River-the Major Tributary Of Songhua River Basin

Name:Gu Xiao LinMajor:Environmental ScienceTutor:Xie Zhong Yan, Tang JieThe Eco-environment is the human society livelihood development and the unreplaceable material base.Protectiing and improving the ecological environment is the basic policy which safeguards sustainable development of our country's social economy. Water is the basic element of the ecological environment and the important condition which supports normal working of the terrestrial life system and non-life system.It is also the capital resource and the material basis for the economic development and the social development of a nation or a area. The region's hydrology water situation play a important part to the ecological equilibrium. Yitong river is the mother river for Changchun. It has admitted massive production waste and the sanitary sewage of Changchun and the downstream city for many years.That Causes the aggravation of river's water pollution and the aquatic organism to vanish the shortage of eco-environment water requirement and so on a series of ecological environment question.Developing the Study on eco-environment water requirement in Yitong river basin is paly a important part to sustainable development of our country's social economy and ecological environment.This research belongs to fund project of "national water pollution control and treatment major science and technology project", and finished the thesis based on it while in master period. Thereinafter the thesis is introduced within five parts:(1) The thesis discusses the concept, the characteristic and the connotation of eco-environment water requirement, summarizes the research present situation and the research technique of the domestic and foreign eco-environment water requirement. And it introduces in detail computational method and the model of domestic and foreign the outer river eco-environment water requirement and the inner river one, including each kind of computational method's good and bad points.(2) According to Yitong River basin main environment question and basin ecological structure characteristic,useing the 3S technology to the ecological regionalization, divides the composition structure of the Yitong River basin's eco-environment water requirement.It mainly includes inner river eco-environment water requirement and outer eco-environment water requirement. The inner river eco-environment water requirement includes inner river water requirement for basic fuction, inner river water requirement for self purification, inner river water requirement for evaporation, inner river water requirement for leakage and inner river water requirement for sediment discharge. The outer eco-environment water requirement includes eco-environment water requirement for vegetative cover, eco-environment water requirement for lake and eco-environment water requirement for city.(3) According to the constitution and characteristic of Yitong River basin eco-environment water requirement, separately choose suitable method and the model to estimate. Choosing the Tennant to estimate the inner river water requirement for basic fuctiong, and the result is 0.80×108m3;Choosing the water quality model to estimate the inner river water requirement for self purification, and the result is 3.71×108m3;Respectively choosing the corresponding formula method to estimate the inner river water requirement for evaporation, leakage and sediment discharge, and the result is 0.30×108m3,0.12×108m3 and 0.18×108m3;The calculation process of eco-environment water requirement for vegetative cover is:First withdraws the corresponding cover type area using ARCGIS software from the research area land utilization chart and the vegetation type chart,after that using the penman formula,area quota method and phreatic water evaporation method to estimate the outer river water requirement for vegetative cover, and the result is 52.02×108m3; The eco-environment water requirement for lake using the minimum water level method to estimate and the result is 1.23×108m3; The eco-environment water requirement for city using the area quota method to estimate and the result is 0.63×108m3.Summing up the above, the inner river eco-environment water requirement of Yitong River basin is 5.11×108m3, for the total eco-environment water requirement is 8.7%,and the outer eco-environment water requirement is 53.88×108m3,for the total eco-environment water requirement is 91.3%.(4) The thesis carry on surplus-deficit analysis specific to the inner river eco-environment water requirement of Yitong River basin month by month,including inner river water requirement for basic fuctiong and inner river water requirement for self purification two parts. The findings indicated,there are varying short of eco-environment water requirement in all the hydrologic station of Yitong River basin.And the water shortage of the Yitong hydrologic station and the Xilicheng hydrologic station is more serious in the summer, as the reason is the agricultural non-point pollution in Xilicheng reservoir upstream is more in the summer. The water shortage of the Nongan hydrologic station is serious in every month of the year,as th reason is the closure control of Xilicheng reservoir and the over standard of COD in downstream in every month of the year.(5) The thesis carry out water balance analysis of the total eco-environment water requirement and the total water resources.Although there is not water shortage in the inner river eco-environment water requirement of Yitong River basin, but the water assigned to each month is serious lack, it for the total water resources is 85.3%.And there is not water shortage in the outer river eco-environment water requirement of Yitong River basin at present,for the total water resources is 52.4%.But along with social economy development and living standards enhancement, industry water requirement and agriculture water requirement will further aggravate to occupy the eco-environment water requirement, so the imbalance between supply and demand of water resources will intensify. Therefore, the basin management department should take the effective action in time to prevent the further aggravation of the water scarcity phenomenon.(6)As above estimation and analysis, this article proposed reasonable and practicable making-up mode of water.On the one hand,it should be feasible to adjust the present operation mode of Xilicheng reservoir,and bring the downstream eco-environment water requirement into reservoir operation.On the other hand,many ecological recovery project and making-up water measure in the Changchun could be teken to relief the shortage situation of downstream eco-environment water requirement.Simultaneously, the further making-up water studies should be developed in the Yitong River basin.