Zhang Ding, Huang Rong, Gao Xue-Song
College of Resources, Sichuan Agricultural University, Chengdu 611130, China.
Huan Jing Ke Xue. 2022 Feb 8;43(2):946-956. doi: 10.13227/j.hjkx.202105139.
The purpose of this study was to explore the spatial distribution characteristics and potential ecological risk factors of heavy metal pollution in cultivated soil in the transitional zone of a typical mountain plain. In this study, a county in Sichuan Province, which has the typical transitional topography of the Chengdu Plain-Longmen Mountain transition zone, was taken as the study area. Geostatistics and potential ecological risk index methods were used to analyze the spatial distribution of Cd, Cr, Cu, Pb, and Zn from cultivated land in the study area, and a potential ecological risk assessment was carried out. This was combined with geographical detector analysis to further explore the main influencing factors leading to the spatial difference in potential ecological risk. The results showed that:① The average values of (Cd), (Cr), (Cu), (Pb), and (Zn) of cultivated land in the study area were 0.39, 123.00, 31.28, 51.04, and 119.66 mg·kg, respectively, which were more than 2.60, 1.59, 1.19, 2.00, and 1.54 times the soil background value in the study area. ② The high value areas of Cd and Cr in cultivated land in the study area were mainly distributed in the west of the mountain area, the south of the transition zone, and the west of the plain area; the high value areas of Cu and Zn were mainly distributed in the west of the mountain area; the high value areas of Pb were mainly distributed in the south of the transition zone and the west of the plain area; and the low values of the five heavy metals were mainly distributed in the north of the transition zone. ③ The soil of cultivated land in the study area was dominated by slight potential ecological risk, and the average value of potential ecological risk index of heavy metals was Cd(32.58) > Pb(3.12) > Cu(2.82) > Cr(1.58) > Zn(0.98). Cd was the main factor causing the potential ecological risk of cultivated land in the study area. ④ There were significant differences in the key influencing factors of soil potential ecological risk of cultivated land in different topographic regions of the study area. The distance from the river and the soil type were the key factors affecting the mountain area; the multiple cropping index and the distance from the industry and mine were the key factors affecting the transition zone, and the soil pH value and the amount of chemical fertilizer were the key factors affecting the plain area.
本研究旨在探讨典型山地平原过渡区耕地土壤重金属污染的空间分布特征及潜在生态风险因素。本研究以四川省一个具有成都平原—龙门山过渡区典型过渡地形的县为研究区域。采用地统计学和潜在生态风险指数方法，分析研究区域耕地中镉（Cd）、铬（Cr）、铜（Cu）、铅（Pb）和锌（Zn）的空间分布，并进行潜在生态风险评估。结合地理探测器分析，进一步探究导致潜在生态风险空间差异的主要影响因素。结果表明：①研究区域耕地中（Cd）、（Cr）、（Cu）、（Pb）和（Zn）的平均值分别为0.39、123.00、31.28、51.04和119.66mg·kg，分别是研究区域土壤背景值的2.60、1.59、1.19、2.00和1.54倍以上。②研究区域耕地中Cd和Cr的高值区主要分布在山区西部、过渡区南部和平原区西部；Cu和Zn的高值区主要分布在山区西部；Pb的高值区主要分布在过渡区南部和平原区西部；五种重金属的低值区主要分布在过渡区北部。③研究区域耕地土壤以轻微潜在生态风险为主，重金属潜在生态风险指数平均值为Cd（32.58）>Pb（3.12）>Cu（2.82）>Cr（1.58）>Zn（0.98）。Cd是导致研究区域耕地潜在生态风险的主要因素。④研究区域不同地形区域耕地土壤潜在生态风险的关键影响因素存在显著差异。距河流距离和土壤类型是影响山区的关键因素；复种指数和距工矿距离是影响过渡区的关键因素，土壤pH值和化肥施用量是影响平原区的关键因素。
