Comprehensive Evaluation And Countermeasure Analysis Of Water Ecological Environment In Haihe River Basin

With the rapid development of climate change and social economy,Haihe River Basin has gradually appeared some water ecological environment problems,such as river blanking,water pollution,wetland atrophy and habitat barrier,etc.The treatment and protection of water ecological environment has become the key problem of ecological civilization construction in Haihe River Basin.This thesis evaluates the water ecological environment of Haihe River Basin by constructing a reasonable comprehensive evaluation system of water ecological environment.Based on the evaluation results,it puts forward watershed governance countermeasures.The research results are as follows:(1)Construct a comprehensive evaluation system of water ecological environment in Haihe River Basin.With the combination of water ecological environment requirements and ecological environment evaluation system construction principles in Haihe River Basin,the assessments of water quantity,water quality,water space,water system connection and aquatic environment are selected as the first level indicators of the water ecological environment evaluation system in Haihe River Basin.There were 1secondary index for water quantity evaluation,3 secondary indexes for water quality evaluation,1 secondary index for water space evaluation,4 secondary indexes for water system connection evaluation,and 3 secondary indexes for aquatic environment.(2)Evaluate the comprehensive status of water quantity,water quality,water space,water system connection and aquatic environment in Haihe River Basin.In terms of ecological water quantity assessment,the ecological base flow compliance rate of Haihe River Basin was 60.51%,and the evaluation result was “medium”.The ecological base flow compliance rate of Beisanhe River was highest,but the ecological base flow compliance rate of Tuhaimajia River was lowest.In terms of water quality assessment,the stream-length ratio of class I～III water quality,water function area compliance rate and average eutrophication index of lakes and reservoirs were 44.17%,50% and 58 points respectively.The evaluation results of class I～III water quality stream-length ratio,water function area compliance rate and average eutrophication index of lakes and reservoirs in Haihe River Basin were all “bad”.Class I～III water quality stream-length ratio in Luanhe River and Coastal Rivers in Eastern Hebei Province and water function area compliance rate in Tuhaimajia River were highest,and average eutrophication index of lakes and reservoirs in Zhang-Wei River was lowest.In assessment of water space,the water spatial retention rate of Haihe River Basin was only 0.56%,and the evaluation result was “bad”.In assessment of water system connection,it is assessed that the results of water system ring degree,joint connection rate,hydrologic connectivity and longitudinal connectivity index in Haihe River Basin were “bad”,“good”,“medium” and “medium”.Except for the evaluation results of joint connection rate were all “good” or above,the evaluation results of water system connectivity evaluation index were mostly “medium” or below.In Haihe River Basin aquatic environment,the evaluation result of fractional vegetation coverage,river-lake littoral zone stability and river-lake littoral zone comprehensive index evaluation were“medium”,“good” and “medium”.In aspect of comprehensive index,Haihe River Basin comprehensive index was 23.59 and the evaluation result of comprehensive index was “medium”.(3)The countermeasures of water ecological environment control in Haihe River Basin are put forward.There are some problems in Haihe River Basin which are obviously deficient ecological water quantity,damaged ecological hydrological rhythm,water quality deterioration,water space shrinking,water system barrier,habitat destruction and so on.Therefore,six suggestions are put forward in this thesis.Firstly,ensure and improve the ecological water quantity.Secondly,ensure the ecological hydrological rhythm of the lake.Subsequently,strengthen the construction of water conservation society.At the same time,insist on promoting the river chief system management and enhance the horizontal and three-dimensional connectivity of rivers and lakes.Finally,promote habitat protection.