成都平原白菜种植地土壤重金属污染关联性及生态风险评价

Correlation and Ecological Risk Assessment of Soil Heavy Metal Pollution in Cabbage Plantation of Chengdu Plain

通过田间试验调查研究了成都平原白菜种植地土壤和白菜可食部分中重金属污染状况及其关联性,并采用单项污染指数法、内梅罗综合指数法和潜在生态危害指数法分析了土壤重金属污染程度,同时利用生物富集系数法探讨了白菜可食部分对重金属的富集能力。结果表明:白菜可食部分中重金属含量无超标,但对Cd的富集能力表现较强,土壤中仅Cd轻微污染,超标率达3.33%,以及生态危害主要风险因子为Cd和Hg。土壤Cd和Cu与有机质和pH值呈显著性正相关,白菜可食部分As与土壤Hg,以及Hg与土壤Cu呈极显著正相关。综合反映了土壤Cd、Cu、Hg在白菜生长过程中可食部分中富集的风险较高,需要格外关注。

A field experiment was conducted to investigate the pollution status and correla tion of heavy metals in soil and edible part of Chinese cabbage in Chengdu plain.The single pollution index method,Nemero comprehensive index method and potential ecological hazard index method were used to analyze the pollution degree of heavy metals in soil.And the bioaccumulation coefficient method was used to explore the enrichment ability of edible part of Chinese cabbage to heavy metals.The results showed that the contents of heavy metals in the edible part of Chinese cabbage did not exceed the standard,but the enrichment ability of cabbage to Cd is strong.Only Cd which standard-exceeding rate was 3.33%slightly polluted the soil.The main risk factors of ecological harm were Cd and Hg.Cd and Cu in soil were significantly positively correlated with organic matter and pH,and As and Hg in the edible part of Chinese cabbage were significantly positively correlated with Hg and Cu in soil.It comprehensively reflects that there is a high risk of soil Cd,Cu and Hg enrichment in the edible part of Chinese cabbage during growth,which needs special attention.