【摘要】 为了解齐齐哈尔市建城区城市绿地土壤重金属来源与健康风险,在生产绿地、居住绿地、公园绿地、工业绿地、附属绿地、防护绿地、道路绿地内采集表层0～20 cm土壤样品,测定重金属含量,并用单因子指数法表征污染水平。应用美国环境保护部（US EPA）健康风险评价模型评估人群暴露土壤重金属的健康风险,以期为城市绿地系统规划和开敞空间规划提供有益的指导。结果表明:各绿地土壤中均有重金属元素含量超过黑龙江省土壤背景值,其中Cu、Zn、Pb、Cr、As表现更为突出;Cr在生产绿地、居住绿地、公园绿地、防护绿地及道路绿地土壤中最高,Hg最低,而工业绿地和附属绿地土壤中Zn最高,Hg最低;单向污染评价显示,居住绿地中的As、公园绿地中的As和Cr、防护绿地中Hg的单因子污染指数大于1,已产生污染。Cu、Pb、Cr、Zn含量高值点主要出现在公园绿地,该绿地土壤中Cu、Pb、Cr、Zn的累积可能受到居民生活和交通活动的多重影响;As含量的高值点主要分布在工业绿地土壤中,源于市区内的工业性企业在各个生产环节产生的污染物和煤炭燃烧的排放富集于土壤。Hg含量的高值点出现在防护绿地中,略超出黑龙江省土壤背景值,需要关注。城市绿地土壤中重金属对成人不存在非致癌健康风险;而居住绿地、公园绿地的土壤中As、Cr和生产绿地土壤中的Cr对儿童存有潜在的非致癌健康风险,需要引起注意。城市绿地土壤中,As、Cr呼吸对成人和儿童的致癌风险指数（CR）平均值均大于US EPA推荐的土壤治理标准(10^-6),但未超过有关专家所建议的土壤治理标准(10^-6～10^-4),其致癌风险已达到了较高的水平,应引起重视;不同绿地类型内人群暴露土壤重金属的非致癌风险和致癌风险存在一定的差异,进行城市绿地系统规划时要科学制定绿地空间布局,降低对人类健康的风险。更多还原

【Abstract】 In order to understand the source and health risks of soil heavy metals in the urban green space of Qiqihar City, we collected soil samples from 0-20 cm depth of the production green space, residential green space, park green space, industrial green space, auxiliary green space, protective green space and road green space and determined their heavy metal contents. The single factor index method was used to characterize the level of pollution. The United States Environmental Protection Agency（US EPA） health risk assessment model was used to assess the health risks of heavy metals exposed to the soil, in order to provide useful guidance for urban green space system planning and open space planning. The results showed that the contents of heavy metals, especially Cu, Zn, Pb, Cr and As, in all green space soils exceeded the background value of Heilongjiang Province. The Cr content was the highest and the Hg content was the lowest in producing green space, residential green space, park green space, protective green space and road green space, while Zn was the highest and Hg was the lowest in the industrial green land and affiliated green land. The one-way pollution evaluation showed that As in the residential green space, As and Cr in the park green space, and Hg in the protective green space were at polluted level and their single factor pollution indices were greater than 1. The high values of Cu, Pb, Cr and Zn mainly appeared in the park green space. The accumulation of soil Cu,Pb, Cr and Zn in the green space may be affected by the multiple activities of residents’ living and transportation. The high content of soil As was mainly distributed in the industrial green space, and was from the emissions of pollutants and coal combustion generated by industrial enterprises in the urban area and concentrated in the soil. The high content of Hg appeared in the protective green space, slightly exceeding the soil background value of Heilongjiang Province, and needed to attention. Heavy metals in urban green space had no non-carcinogenic health risks for adults,while soil As and Cr in residential greenbelts and park greenbelts and Cr in production greenbelts had potential non-carcinogenic health risks for children and need to attention. In urban greenfield soils, the average CR of As and Cr breaths for adults and children was greater than soil management standard(10^-6) recommended by US EPA, but did not exceed the soil remediation standards(10^-6 to 10^-4) recommended by relevant experts. The risk of carcinogenesis reached a relatively high level and should be paid attention. There was a certain difference in the non-carcinogenic risk and the carcinogenic risk of heavy metal exposure among different types of green spaces. The spatial layout of green space should be scientifically established in planning urban green space systems in order to reduce the human health risk.更多还原