【摘 要】
:
Evaluation of the river ecological environment can provide a basis for river management and ecological restoration.To conduct a comprehensive health assessment of the rivers in Tianjin,their biological,physical,and chemical indicators are investigated on
【机 构】
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State Key Laboratory of Environmental Criteria and Risk Assessment,Chinese Research Academy of Envir
论文部分内容阅读
Evaluation of the river ecological environment can provide a basis for river management and ecological restoration.To conduct a comprehensive health assessment of the rivers in Tianjin,their biological,physical,and chemical indicators are investigated on the basis of 32 river monitoring sites from August to September 2018.The comprehensive pollution and ecological integrity indexes of the rivers are analyzed.Results of the two evaluations,compared to achieve the river ecological environment evaluation,are as follows.1) Index of Ecological Integrity evaluation shows that among the sampling points,18.8%are “healthy”,28.1% are “sub-healthy”,40.6% are “fair”,6.3% are “poor”,and 6.3% are “very poor”.2) The comprehensive evaluation of the chemical properties of the 32 river ecosystems in Tianjin shows severe overall river pollution and low standard water function area.Of the total sampling sites,16 (50%) are heavily contaminated and 10(31.3%) are moderately contaminated.Excessive chemical oxygen demand and ammonia nitrogen are the main causes of water pollution.3) The Index of Ecological Integrity(IEI) has high correspondence with environmental factors.Pearson correlation analysis results show that the IEI index is significantly correlated with permanganate index (R =-0.453;P =0.023 < 0.05).Analysis results using BEST show that ammonia nitrogen is the best environmental parameter to explain the changes in IEI (Rho=0.154;P =0.02 < 0.05) and those using RELATE show significant correlation between the biotic index and the environmental parameter matrices (Rho=0.154;P =0.034 < 0.05).
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