鄱阳湖沉积物重金属污染影响因素分析——基于STIRPAT模型

为探究人类活动对鄱阳湖沉积物重金属污染的影响，于2017年10月在鄱阳湖入口、出口及湖区布设20个采样点位，开展鄱阳湖沉积物重金属表层及垂向分布特征调查，评价其潜在生态风险.利用¹³⁷Cs和²¹⁰Pb计年法推算出鄱阳湖沉积物的平均沉积速率，并结合柱状分层样品重金属含量，得出具体年代的重金属蓄积特性.基于STIRPAT模型，通过偏最小二乘回归分析得到鄱阳湖沉积物重金属演变与总人口数量、城镇化率、实际人均GDP、绿色专利申请数、第二产业占比、第三产业占比6种社会经济指标的多元非线性模型.结果表明：（1）鄱阳湖表层沉积物重金属Cu污染最为严重且生态风险程度最高， 地累积指数为“强”或“中-强”污染范畴，单因子潜在生态风险指数平均值为47.25，属于“中等”生态风险.整个湖区的总潜在生态风险指数RI平均值为107.07，表明鄱阳湖表层沉积物重金属总体处于低生态危害水平.（2）1988~2017年总人口数量是影响鄱阳湖沉积物重金属Cd和Cu污染的最主要正向因素，其他正向因素为第二产业占比、第三产业占比、城镇化率及实际人均GDP，绿色专利申请数所反映出的区域绿色技术创新能力及环保研发投入对鄱阳湖沉积物重金属Cd、Cu污染具有负相关关系.

Analysis on influencing factors of heavy metal pollution in sediments of Poyang Lake based on STIRPAT Model

In order to explore the impact of human activities on the heavy metal pollution in the sediment of Poyang Lake, 20sampling sites were set up at the entrance, outlet and lake area of Poyang Lake in October 2017. To investigate the surface and vertical distribution characteristics of heavy metals in the sediments of Poyang Lake and evaluate their potential ecological risks. The average deposition rate of Poyang Lake sediment was calculated by ¹³⁷Cs and ²¹⁰Pb dating methods, and the heavy metal accumulation of specific years was obtained by combining the heavy metal content of stratified samples. Based on the STIRPAT model, the multiple nonlinear models of the evolution of heavy metals in the sediment of Poyang Lake, including the total population, urbanization rate, actual GDP per capita, number of green patent applications, the proportion of the second industry and the proportion of the third industry, were obtained by the partial least square regression analysis. The results showed that: (1) the heavy metal Cu pollution in the surface sediment of Poyang Lake was the most serious and the ecological risk degree was the highest, the land accumulation index was "strong" or "medium strong" pollution category, the average value of the single factor potential ecological risk index was 47.25, which was "medium" ecological risk. The average RI of the whole lake area was 107.07, the results showed that the heavy metals in the surface sediments of Poyang Lake were in the low level of ecological harm.(2) the total population in 1988~2017 was the most important positive factor affecting heavy metals Cd and Cu pollution in Poyang Lake sediment, other positive factors were the proportion of the secondary industry, the proportion of the tertiary industry, the urbanization rate and the actual GDP per capita. Regional green technology innovation capacity and environmental protection R & D investment, which was reflected by the number of green patent applications, had anegative correlation with the pollution of heavy metals Cd and Cu in the sediment of Poyang Lake.