综合降镉技术在重金属轻度污染农田中对稻米镉含量的影响

试验以湘潭县杨嘉桥镇原种场轻度污染农田为对象,早稻以‘中嘉早17号’和‘湘早籼24号’为供试品种,晚稻以‘H优518’和‘岳优27’为供试品种,采用"VIP+n"综合降镉技术,开展"VIP+n"修复技术模式区域化研究与示范工作,旨在探究不同"VIP+n"降镉技术组合模式在轻度镉污染区域的适应性,围绕轻度镉污染区域的生态、经济、种植习惯因地制宜地构建最佳"VIP+n"县域本土化技术模式。结果表明:早稻米镉含量低于晚稻;不同"VIP+n"降镉技术组合模式在轻度镉污染区域适应性良好且降镉率至少在40%以上,都能够降低稻米镉含量并使其远低于国家标准0.2 mg/kg。结论:从生态效益、经济效益和稻米降镉效果来看,"当地水稻品种+撒施石灰"修复技术组合是降低轻度重金属污染农田稻米镉含量的最佳推广模式。

Effect of Comprehensive Cadmium Reduction Technology on Cadmium Content in Paddy Fields with Light Heavy Metal Pollution

A field experiment was conducted to explore the adaptability of different combination models of “VIP+n” cadmium-reduction technology in light cadmium pollution field at Yangjiaqiao Town, Xiangtan County, using early rice (‘Zhongjiazao 17’ and ‘Xiangzaoxian 24’) and late rice (‘Hyou 518’ and ‘Yueyou 27’) as materials. Focusing on the ecology, economy and planting habits of the areas with light cadmium pollution, the best localization technology mode of “VIP+n” of the county was constructed. The results showed that the cadmium content in early rice was lower than that in late rice. Different combinations of “VIP+n” cadmium-reduction technologies had good adaptability in areas with light cadmium pollution and the cadmium reduction rate was at least above 40%, which could reduce the cadmium content of rice to be lower than the national standard of 0.2 mg/kg. Thus, the remediation technology combination of “local rice variety + lime” is the optimum promotion mode to reduce cadmium content of rice in farmland lightly polluted by heavy metals in terms of ecological benefit, economic benefit and cadmium-reduction of rice.