基于乡镇尺度的农田土壤中污染物来源解析及风险评价

大比例尺的区域土壤调查已经展开,但以乡镇为比例尺的调查很少,因此,本文以绵远河、石亭江两个水系流域乡镇的农田土壤为研究对象,在查明污染物浓度的基础上,对其来源及污染程度进行研究。相关性分析、聚类分析和因子分析的结果显示,两个水系流域农田土壤中污染物来源为自然源、交通源、农业活动源及工业活动源;绝对主成分得分-多元线性回归(APCS-MLR)模型解析结果与相关性分析、聚类分析、因子分析结果相符。生态风险评价表示两个水系流域农田土壤均受到中等程度的生态危害,其中Cd的风险程度最高,石亭江流域农田土壤中污染程度更为严重。

Source Apportionment and Risk Assessment of Pollutants in Farmland Soil Based on Township Scale

Large-scale regional soil surveys have been carried out, but few surveys have been carried out on the scale of towns and villages. Therefore, this paper takes the farmland soil of towns and villages in Mianyuan river and Shiting river drainage basins as the research object and studied the pollution source and degree based on the investigation of pollutants'' concentration. The results of correlation analysis, cluster analysis and factor analysis showed that the pollutants in farmland soil in the two drainage basins were natural sources, transportation sources, agricultural sources and industrial sources. The analytical results of absolute principal component scores-multiple linear regression (APCS-MLR) model are consistent with the results of correlation analysis, cluster analysis and factor analysis. According to the ecological risk assessment, the farmland soils in the two river basins were exposed to moderate ecological damage, with the highest risk of Cd and more serious pollution was found in the Shiting river basin.