基于Catboost算法的中国典型农业区重金属污染特征及影响因素分析  

Analysis of heavy metal pollution characteristics and influencing factors in China's typical agricultural areas based on Catboost algorithm

作　　者：李珊[1,2] 杨济妮 苏贵金 李倩倩[2] 孟晶[2] 史斌[2] LI Shan;YANG Jini;SU Guijin;LI Qianqian;MENG Jing;SHI Bin(Henan Institutes of Advanced Technology,Zhengzhou University,Zhengzhou,450003,China;Key Laboratory of Environmental Nanotechnology and Health Effect,Research Center for Eco-Environmental Sciences,Chinese Academy of Sciences,Beijing,100085,China;Foreign Cooperation and Exchange Center of the Ministry of Ecology and Environment,Beijing,100035,China)

机构地区：[1]郑州大学河南先进技术研究院,郑州450003 [2]环境纳米技术与健康效应重点实验室,中国科学院生态环境研究中心,北京100085 [3]生态环境部对外合作与交流中心,北京100035

出　　处：《环境化学》2024年第10期3377-3387,共11页Environmental Chemistry

基　　金：国家重点研发计划(2018YFC1800300);国家自然科学基金(42277387)资助.

摘　　要：土壤是保障人类生存和发展的物质基础,农田土壤与人类生产生活密切相关,农田土壤污染问题值得关注.本文选取东北三省、京津冀和长江经济带作为研究区域,通过文献调研筛选出2000—2020年发布的400篇相关文献,收集到2052表层土壤样本,通过统计学、空间分析和机器学习等方法对其污染特征进行分析.结果表明,与农用地最严格的筛选值标准相比,3个研究区域Cd污染问题较为突出,东北三省、京津冀和长江经济带的超标率分别为37.5%、34.0%和45.8%,长江经济带也存在Cu污染问题,其超标率为30.6%;进一步将采样点位分为矿区周边点位、市郊区点位和其他农田点位,采用潜在生态风险指数法评价表明,矿区周边样点严重和重风险占比(54.8%)显著高于市郊区样点(37.2%)和其他农田样点(36.6%).采用Catboost模型进行影响因子识别发现,矿区周边农田主要受选矿、尾矿暴露等造成的Cd和Hg污染影响,而市郊区农田主要受商业、工业和交通运输业等人类活动带来的Hg污染影响,其他农田土壤中主要受农药化肥的施用以及大型器械化带来的Cd污染影响.Soil is the material foundation for human survival and development.Agricultural soil is closely related to human production and life,and the issue of agricultural soil pollution deserves attention.This study focuses on the research areas of the three northeastern provinces,the Beijing-Tianjin-Hebei region,and the Yangtze River Economic Belt.By conducting literature research,400 relevant articles published between 2000 and 2020 were selected,and 2,052 topsoil samples were collected.Pollution characteristics were analyzed using statistical,spatial analysis,and machine learning methods.The results indicate that,compared to the strictest screening values for agricultural land,Cd pollution is more prominent in the three research areas,with exceedance rates of 37.5%,34.0%,and 45.8%for the three regions,respectively.The Yangtze River Economic Belt also exhibits Cu pollution with an exceedance rate of 30.6%.Further classifying the sample sites into mining area adjacent sites,suburban area sites,and other farmland sites,an assessment using the potential ecological risk index(PERI)method shows that mining area adjacent sites have significantly higher proportions of severe and high-risk pollution(54.8%)compared to suburban area points(37.2%)and other agricultural field points(36.6%).The Catboost model was employed to identify influencing factors,revealing that agricultural fields adjacent to mining areas are mainly affected by Cd and Hg pollution caused by ore selection and tailings exposure.Suburban area fields are primarily influenced by Hg pollution resulting from human activities such as commerce,industry,and transportation.Other agricultural fields'soil is mainly affected by Cd pollution due to the application of pesticides and fertilizers and the use of large-scale mechanization.

关 键 词：农田土壤 重金属 污染特征 Catboost 模型 影响因素. 

分 类 号：X-1[环境科学与工程] O6[理学—化学]