单 位：
北京师范大学地表过程与资源生态国家重点实验室;黄土高原土壤侵蚀与旱地农业国家重点实验室水土保持研究所西北农林科技大学
关键词：
重金属污染;单因子污染指数;内梅罗污染指数;坡耕地;水蚀区
摘 要：
土壤重金属污染已成为威胁国家粮食安全的重要因素,为探讨我国东部水蚀区坡耕地土壤重金属空间分布特征及污染状况,依据土壤类型、土壤质地等因素选取了36个采样点,采用单因子污染指数法和内梅罗污染指数法,以《土壤环境质量标准》(GB15618—2008)二级标准为评价依据,研究了As,Cd,Cr,Cu,Ni,Pb,Zn 7种土壤重金属元素的空间分布特征及污染程度。结果表明:(1)Cd超标率高达13.9%,是东部水蚀区最主要的土壤重金属污染元素,As,Cr,Cu元素的污染概率较高,为5.6%;(2)长江以南地区的坡耕地重金属污染程度显著高于长江以北地区,南方山地丘陵区是我国水蚀区六个二级分区中污染最严重的区域,其次为四川盆地及周围山地丘陵区、云贵高原区、东北低山丘陵和漫岗丘陵区、西北黄土高原区、北方山地丘陵区;(3)湖南宁远和广东湛江两点综合污染指数最高,分别为2.73和2.51,属中污染水平;(4)36个采样点中污染水平处于安全、警戒线、轻污染、中污染的比例分别是77.8%,8.3%,8.3%和5.6%,表明我国东部水蚀区绝大多数坡耕地(86.1%)重金属含量未达到污染水平,但仍有13.9%的坡耕地受到不同程度的土壤重金属污染。研究结果对明确我国水蚀区坡耕地土壤重金属污染现状,保护农业生态环境,保障粮食安全具有重要意义。
译 名：
Soil Heavy Metal Spatial Distribution and Pollution Assessment of Sloping Farmland in the Water Erosion Zone of China
作 者：
MA Qianhong;ZHANG Guanghui;GENG Ren;WANG Bing;State Key Laboratory of Earth Surface Process and Resource Ecology,Beijing Normal University;Faculty of Geographical Science,Beijing Normal University;State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau,Institute of Soil and Water Conservation,Northwest A&F University;
关键词：
heavy metal pollution;;single factor pollution index;;Nemerow pollution index;;sloping farmland;;the water erosion zone of China
摘 要：
Soil heavy metal pollution has become an important factor which threatens the national food security.To investigate the spatial distribution of soil heavy metals(As,Cd,Cr,Cu,Ni,Pb,Zn)and pollution situations of sloping farmland in the water erosion zone of China,36 sampling points were selected according to soil types and soil textures.The single factor pollution index and the Nemerow pollution index were calculated,and the pollution degree was classified according to the second grade values from the Standard of Soil Environment Quality(GB15618—2008).The results showed that:(1)the pollution probability of Cd was 13.9%,which significantly exceeded the pollution levels of other heavy metals,so Cd was the most important soil heavy metal pollution factor in this region;in addition,As,Cr and Cu had a high pollution probability,and the rate was 5.6%;(2)compared with the north area of the Yangtze River,soil heavy metal pollution of the sloping farmland in the south area was significantly serious;the soil heavy metal pollution of southern mountain and hill region was the most serious among the six secondary erosion regions,followed by the Sichuan Basin and surrounding hill region,the Yunnan—Guizhou Plateau region,the northeast low mountain and rolling hill region,the Loess Plateau region,and the northern mountain and hill region;(3)compared with other sampling points,Ningyuan of Hu′nan Province and Zhanjiang of Guangdong Province had the highest Nermerow indices(2.73 and 2.51),which belonged to the moderate pollution level;(4)the proportions of pollu-tion degrees ranked as safety,warning line,light pollution,moderate pollution were 77.8%,8.3%,8.3%and5.6% of the total area of sloping farmland,respectively.The proportions showed that most sloping farmland(about 86.1%)in the water erosion zone of China was relatively safe,but about 13.9% of sloping farmlands might suffer from heavy metal pollution.These results had great significance for identifying soil heavy metal pollution situation of sloping farmland,protecting agroecological environment and ensuring the food security in the water erosion zone of China.
