砷污染农田的田间试验设计和效果评估

Field Experiment Design and Effectiveness Evaluation for Arsenic-Contaminated Farmland

文章以湖北省黄冈市某镇砷污染农田为试验区,通过15个当地主栽水稻品种的种植和铁氧化物、腐殖质酸、生物质炭、黏土矿物4种不同钝化剂的组合和配比,在保证农产品质量安全的前提下,筛选出符合当地种植习惯的低积累水稻品种和钝化剂配比及投加量。结果表明,不同品种水稻对砷的富集能力不同,其中丰籼占为低积累水稻品种,且农产品产量无显著降低;不同钝化剂、不同添加量均能降低水稻籽粒中砷含量,当铁氧化物、腐殖质酸、生物质炭和黏土矿物4种钝化剂的投加量分别为100 kg/亩、200 kg/亩、50 kg/亩和100 kg/亩时,可以使得水稻籽粒中砷含量降低至0.2 mg/kg以下,符合国家相关标准要求。This study uses arsenic-contaminated farmland in a town in Huanggang City, Hubei Province, as the experimental area. By planting 15 locally predominant rice varieties and using different combinations and ratios of four different amendments, including iron oxides, humic acids, biochar, and clay minerals, aimed to screen for low-accumulation rice varieties and the appropriate combinations and dosages of amendments that conform to local farming practices while ensuring the safety of agricultural products. The results showed that different rice varieties have varying abilities to accumulate arsenic, with Fengxianzhan rice variety identified as a low-accumulation variety, and no significant reduction in crop yield. Different amendments and dosages can all reduce the arsenic content in rice grains. When the dosages of iron oxide, humic acid, biochar, and clay minerals were 100 kg/mu, 200 kg/mu, 50 kg/mu, and 100 kg/mu, respectively, the arsenic content in rice grains was reduced to below 0.2 mg/kg, which meets the relevant national standards.