Study On The Coupling Relationship Between Sedimentary Pollution And Human Economic Activities Of Lianhuan Lake Basin

With the great development of economy, the interaction of human activities and ecological environment has become more and more significant. Excessive emphasis on economic development may lead to ecological deterioration, while excessive environment protection will probably limit the economy development. Therefore, how to choose apt production method, lifestyle and appropriate activity intensity so as to maintain and improve ecological environment with the development of economy has become a focus of environment-economic research which can promote the coordinate development of ecological environment and economy. Lianhuan Lake lies in Dorbod Mongol Autonomous County. On one hand, human activities can promote the development of economy. On the other hand, these activities will affect the ecological environment, which will act on economy system in turn.In this paper, the study was conducted by applying field research, laboratory experiment, qualitative analysis and quantitative analysis, statistical analysis method, combining ecological economics and synergetics. Regarding Lianhuan Lake basin as the research object, the thesis analyzes the sedimentary pollution characteristics first, and then evaluates the interaction and effect between sedimentary pollution and human economic activities by using principal component analysis method for weight determination. Finally, it discusses the coupling mechanism, dynamic changes, and the coupling process between the two systems based on the establishment of evaluation index system.The main contents and conclusions of this paper are as follows.(1) The distribution and concentration of grain size and magnetic susceptibility show that the sediments in Lianhuan Lake were composed of coarse particles, and the average grain size was mainly controlled by the concentration of sand, while the content of magnetic minerals in sediments was affected mainly by that of coarse silt. The changes of grain size and magnetic susceptibility on the time sequence were probably influenced by not only natural factors such as climate, but also human activities.(2) The correlation analysis results between heavy metal elements and grain size reveal that the distribution of heavy metal elements varies obviously with grain size. And the correlation analysis results between heavy metal elements reflected that, besides products of weathering and erosion, heavy metal elements comes primarily from agricultural pollution, industrial pollution, traffic pollution, etc. The variation characteristics of heavy metal elements corrected by Li on the time sequence indicate that concentration of heavy metal elements is closely related to human agricultural activities, industrial activities, related policies as well as climate change.(3) The distribution features of nutrient elements and the correlation analysis results between them proved that TOC was affected by a number of factors in the process of sedimentation, such as organic productivity, organic matter input, grain size, etc. Furthermore, TOC and TN may have similar source, and TN and TP may not. The changes of nutrient elements on the time sequence are similar with that of human economic activities.(4) Through the study on OCPs and PAHs in sediments of Lianhuan Lake the author considered that DDTs and HCHs were the two main pollutions in OCPs, and there were new HCH pollution and industrial DDT input. What’s more, PAHs were affected by TOC in the process of sedimentary and dominated by high ring PHAs, which come from fuel combustion and oil spill.(5) Fine correlation analysis results between human economic activity index, which includes land use and land cover change index, agricultural activity index and industrial activity index, and sedimentary pollution index illustrate that the sediments have been affected by human economic activities in the process of sedimentation.(6) The dynamic coupling process between sedimentary pollution and human economic activities make it clear that the environmental quality was getting worse and the development of economy was getting further from 1950 s to 2007. The coordination state between the two systems has remained relatively stable upward trend, through low-grade coordination to medium coordination to good coordination. The coupling action between the two systems is rising, and the environment-economy system is moving towards the orderly direction. However, the economy of study area has got development at the expense of environment quality for the past over 50 years, which should be paid more attention to.