摘要
【目的】探究重庆稻田土壤重金属元素的含量特征并对其进行风险评价,为土壤重金属污染防控及耕地土壤保护提供参考依据。【方法】采集重庆市7个典型水稻主产区的稻田土壤样品230个,分析测定土壤样品的pH及Cd、Hg、As、Pb、Cr等5种重金属元素含量,利用内梅罗污染指数评价法与地累积指数评价法进行污染程度分析,并与重庆土壤重金属背景值和农用地土壤风险筛选值进行比对,分析评估重庆稻田土壤重金属污染特征,再通过皮尔逊相关性分析和聚类分析探究土壤重金属污染可能来源。【结果】研究区土壤中Pb、Cd、Cr、As、Hg等5种重金属元素的平均含量分别为25.4、0.312、66.8、4.71、0.0827 mg/kg。通过单因子污染指数与内梅罗污染指数评价法分析,研究区稻田土壤有19.57%的点位处于Cd元素轻污染状态,0.43%的点位处于Hg元素中污染状态,其余点位处于无污染状态。地累积指数分析发现,稻田土壤中Cd处于轻污染水平,其余重金属元素属于无污染水平,但存在极少部分土壤的Hg元素地累积指数极高(4.03,属于强-极强污染等级)。与重庆市土壤背景值比对发现,Cd、Hg元素含量均超过了重庆土壤背景值,分别是背景值的2.84倍、1.38倍,有累积效应;Pb、Cr、As元素含量略低于重庆土壤背景值,基本无富集。通过与农用地土壤风险筛选值比对,所调查的稻田土壤重金属含量均值均小于对应的农用地土壤风险筛选值。相关性及聚类分析发现,重金属污染主要源于成土过程及人为因素。【结论】重庆稻田土壤总体处于清洁状态,但存在Cd、Hg元素的污染风险。
【Objective】The paper provides references for the prevention of heavy metal pollution and the protection of cultivated soil environment through exploring the content characteristics and the risk of heavy metals elements of paddy soil in Chongqing. 【Method】230 paddy soil samples were collected from 7 major and typical rice-growing regions in Chongqing, and the pH and the content of 5 heavy metal elements including Cd, Hg, As, Pb and Cr in paddy soil samples were analyzed. The Nemero pollution index evaluation method and the land accumulation index evaluation method were used to analyze the degree of pollution, and compared with the background value of heavy metals in Chongqing soil and the risk screening value of agricultural land soil. The characteristics of heavy metal pollution in Chongqing paddy soil were analyzed and evaluated. Then, the possible sources of heavy metal pollution in soil were explored through Pearson correlation analysis and cluster analysis. 【Result】The average contents of Pb, Cd, Cr, As and Hg in the paddy soil of the research area were 25.4, 0.312, 66.8, 4.71 and 0.0827 mg/kg, respectively. Through the analysis of single factor pollution index and Nemero pollution index evaluation methods, 19.57% of the paddy soil sites in the study area were in the state of Cd light pollution, 0.43% was in the state of Hg medium pollution, and the remaining points were in the state of no pollution. According to Geo-accumulation index, the paddy soil was lightly polluted by Cd, while the remaining heavy metal elements were at a non-polluted level. However, there were very few soils with extremely high ground accumulation index of Hg(4.03, belonging to the level of strong to extremely strong pollution). It was found that the content of Cd and Hg elements exceeded the background value of Chongqing soil, 2.84 times and 1.38 times of the background value, respectively, with a cumulative effect;The content of Pb, Cr, As elements was slightly lower than the background value of Chongqing soil, and there was basically no enrichment. The average content of heavy metals in the surveyed paddy soil was lower than the corresponding agricultural land soil risk screening value. Correlation and cluster analysis showed that heavy metal pollution mainly originated from soil formation processes and human factors. 【Conclusion】The paddy soil in Chongqing is generally in a clean state, but there is a risk of Cd and Hg contamination.
作者
余鸿燕
唐子茜
王娜
张伟
付婷婷
曾婷婷
黄永川
阎应红
YU Hong-yan;TANG Zi-qian;WANG Na;ZHANG Wei;FU Ting-ting;ZENG Ting-ting;HUANG Yong-chuan;YAN Ying-hong(Chongqing Academy of Agricultural Science,Chongqing 401329,China)
出处
《西南农业学报》
CSCD
北大核心
2023年第5期1066-1073,共8页
Southwest China Journal of Agricultural Sciences
基金
重庆市2021年市级农业发展资金项目(NKY-2021AB013)
重庆市2022年市级财政专项(NKY-2022AC016)。
关键词
稻田
重金属污染
土壤环境质量
内梅罗污染指数
地累积指数
Paddy soil
Heavy metal pollution
Soil environment quality
Nemerow index
Geo-accumulation index
作者简介
第一作者:余鸿燕(1971-),女,高级农艺师,主要从事土壤农化分析研究。E-mail:yuhongyan0317@qq.com;通讯作者:阎应红(1964-),男,高级农艺师,主要从事农业科技信息研究与应用。E-mail:397899137@qq.com。
