摘要
运用2.5 km×2.5 km网格布点,在长江中下游某农田区域采集33个表层土壤样品,利用ICP-AES测定土壤样品中Cd的全量,并利用Tessier浸提法分步提取土壤Cd的5种形态,应用单项污染指数法、地累积指数法和潜在生态风险指数法对土壤Cd污染进行生态风险评价。结果表明:研究区内水田土壤pH值为5.27~6.8,水田Cd的平均值为0.61 mg/kg;旱地土壤pH值为5.06~7.36,旱地Cd平均值为0.66 mg/kg;农田土壤Cd主要以可交换态为主,占比为36.52%,表明区域内土壤Cd的活性相对较高;单项污染指数法与地累积指数法的评价结果显示,研究区污染程度为中度,潜在生态风险评价系数Er为148.12,表现为中高等生态危害。系统分析长江中下游农田土壤中重金属Cd的污染状况和行为特征表明,研究区农作物经长期积累可能会对安全种植产生影响。
Using 2.5 km×2.5 km grid points,33 surface soil samples were collected from a farmland area in the middle and lower reaches of the Yangtze River.The total amount of Cd in the soil samples was determined by ICP-AES,and five forms of Cd in the soil samples were extracted by Tessier extraction step by step.Single pollution index method,land accumulation index method and potential ecological risk index method were used to evaluate the ecological risk of Cd pollution in the farmland soil in the study area.The results showed as following.The average value of Cd in paddy soil was 0.61 mg/kg,pH was 5.27~6.8.The average value of Cd in dry land soil was 0.66 mg/kg,pH was 5.06~7.36.The main form of Cd in farmland soil was exchangeable,accounting for 36.52%,which indicated that the activity of Cd was not always high,and it was harmful to the ecology.The evaluation of single pollution index and land accumulation index showed that the area is the main pollution area,and the pollution degree is moderate.The potential ecological risk coefficient Er of the study area is 148.12,which shows medium and high level ecological hazards.It reveals the pollution status and behavior characteristics of heavy metal Cd in farmland soil in the middle and lower reaches of the Yangtze River.The long-term accumulation of crops in the study area may have an impact on safe planting.
作者
郭展翅
周葆华
赵宽
胡睿鑫
刘勤
GUO Zhanchi;ZHOU Baohua;ZHAO Kuan;HU Ruixin;LIU Qin(School of Resource and Environment,Anqing Normal Univeristy,Anqing 246133,China;Key Laboratory of Aqueous Environment Protection and Pollution Control of Yangtze River in Anhui of Anhui Provincial Education Department,Anqing 246133,China)
出处
《安庆师范大学学报（自然科学版）》
2021年第1期96-101,共6页
Journal of Anqing Normal University(Natural Science Edition)
基金
安徽省科技重大专项项目(17030701057)
安徽省自然科学基金(1908085QD149)
安徽省高等学校自然科学研究重点项目(KJ2018A0374)。
关键词
长江中下游
土壤重金属形态
空间分布特征
风险评价
middle and lower reaches of the Yangtze River
soil heavy metals speciation
spatial distribution characteristics
risk assessment
