Assessment of river ecosystem health in Tianjin City,China:index of ecological integrity and water comprehensive pollution approach

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(R_(ho)=0.154;P=0.02<0.05)and those using RELATE show significant correlation between the biotic index and the environmental parameter matrices(R_(ho)=0.154;P=0.034<0.05).

Impact of Urbanization and Industrialization upon Surface Water Quality:A Pilot Study of Panzhihua Mining Town

In order to investigate the impact of urbanization and industrialization on surface water quality, a pilot study of Panzhihua （攀枝花） mining town was carried out. The urbanization of Panzhihua region was dominated by industry development and population growth. The level of urbanization showed that it was 18.44% in 1965, and reached 45.99% in 1983. Then, it reached 53.71% in 2005, so the urbanization process was very rapid in Panzhihua region. In the process of industrialization, the level of industrialization was fluctuated at around 70% from 1965 to 2005, which was influenced by mining, extracting, and smelting production. In the processes of urbanization, population growth caused an increase in life pollution sources, and an amount of effluents bearing coliform, COD （chemical oxygen demand）, NH4^＋-N, and BOD5 （five-day biological oxygen demand） were released into Jinsha （金沙） River, which could cause decline in the surface water quality. While in the processes of industrialization （especially industrial scale expansion）, more effluent bearing heavy metals could cause degra- dation of surface water quality. Thus, the measures, such as adjusting industry structure, optimizing the cleaning technology, and controlling pollution sources, should be enhanced to alleviate the current state of water quality exacerbation.