海南省农产品基地土壤理化指标和主要无机元素监测与评价

Monitoring and Evaluation of Soil Physical and Chemical Indexes and Main Inorganic Elements of Agricultural Products Base in Hainan Province

[目的]了解海南省农产品基地理化指标和主要无机元素含量特点,评估农产品基地土壤主要无机元素污染风险,支撑农产品基地土壤污染防治。[方法]以8个农产品基地为研究对象,分析3项理化指标(pH、有机质、阳离子交换量)和8种土壤无机元素(镉、汞、砷、铅、铬、铜、镍、锌)含量、分布特点和污染风险。[结果]土壤pH呈强酸性和酸性,阳离子交换量为1.28~10.80 cmol/kg,有机质含量为2.95~24.80 g/kg。土壤镉、汞、砷、铅、铬、铜、镍、锌含量分别为0.02~0.37、0.012~0.126、0.26~6.75、14.7~50.1、10.1~118.0、4.2~23.1、3.7~44.8、14.3~105.0 mg/kg。果园型农产品基地镉含量最高,旱地型农产品基地铬、铜、镍、汞含量最高,水田型农产品基地砷、铅、锌含量最高。各主要无机元素含量平均值均未超过农用地土壤污染风险筛选值。除砷、铜、镍外,其他5个元素含量超过海南省土壤环境背景值,尤以镉最显著。[结论]该研究为农产品基地土壤污染防治和农业生产可持续发展提供技术支撑。

[Objective]To understand the physical and chemical indexes and the content characteristics of main inorganic elements of agricultural product bases in Hainan Province,evaluate the pollution risk of main inorganic elements in soil of agricultural product bases,and support the soil pollution prevention and control of agricultural product bases.[Method]Taking 8 agricultural product bases as research objects,the contents,distribution characteristics and pollution risks of 3 physical and chemical indexes(pH,organic matter,cation exchange capacity)and 8 soil inorganic elements(cadmium,mercury,arsenic,lead,chromium,copper,nickel,zinc)were analyzed.[Result]The soil pH was strongly acidic and acidic,the cation exchange capacity was 1.28-10.80 cmol/kg,and the content of organic matter was 2.95-24.80 g/kg.The contents of cadmium,mercury,arsenic,lead,chromium,copper,nickel and zinc in soil were 0.02-0.37,0.012-0.126,0.26-6.75,14.7-50.1,10.1-118.0,4.2-23.1,3.7-44.8 and 14.3-105.0 mg/kg respectively.The content of cadmium in orchard agricultural product base was the highest,the content of chromium,copper,nickel and mercury in dryland agricultural product base was the highest,and the content of arsenic,lead and zinc in paddy field agricultural product base was the highest.The average value of major inorganic elements did not exceed the risk screening values for soil contamination of agricultural land.Except arsenic,copper and nickel,the other five elements exceeded the soil environmental background value of Hainan Province,especially cadmium.[Conclusion]This study provides technical support for soil pollution prevention and sustainable development of agricultural production in agricultural product base.