[Spatial Distribution and Potential Ecological Risk Assessment of Heavy Metals in Sediments of Suya Lake].

In order to study the pollution status of heavy metals in sediments of Suya Lake, the concentrations of heavy metals Cu, Cd, Cr, Zn, Pb and Ni in sediments were measured at three locations in the center, middle and periphery of Suya Lake, the content characteristics and the pollution status of heavy metals in the study area were analyzed by the method of geoaccumulation index and potential ecological risk index, and the distribution and interrelation of heavy metals were evaluated by Kriging method and correlation analysis. The results showed that, on average, Zn was the highest, 112.87 mg·kg, followed by Cr, the smallest average of Cd was only 0.41 mg·kg. In addition to Cd and Cr, the coefficients of variation of Cu, Zn, Pb and Ni were relatively small, ranging from 24% to 31%, with moderate degree of variation. The coefficients of variation of Cd and Cr were 50.41% and 41.92%, respectively, and the spatial variation was obvious, which indicated that the variation of Cd and Cr was more significant than the others; 2The heavy metals Cu, Cd, Cr, Zn, Pb and Ni had a strong linear relationship, and there was a significant positive correlation, and six kinds of heavy metals had some homologous characteristics, with a common external input; 3The main pollution elements in the study area were Cd, Cr and Zn, the pollution degree was relatively serious, and the scope was extensive. Among them, the pollution degree of Cd was the most serious, the overall pollution level was moderate, and the pollution degree in some sample areas reached up to severe pollution, the pollution status of Cr, Zn and Pb was relatively mild, the pollution status of Cu, Pb and Ni was better, and there was no ecological risk; 4On the whole, the pollution level of the northeastern part of Suya Lake was relatively light, the degree of pollution in the southwest was relatively serious, showing a significant spatial distribution characteristics of decreasing from southwest to northeast, the contents of heavy metals in the samples were higher than those in the southwest of the reservoir, while the northeastern part of the periphery was the area with accumulation of low concentrations of heavy metals., and there was no pollution from Cu, Cr, Zn and Ni.