土壤-水稻/小麦重金属吸收机制与安全调控

为掌握我国水稻和小麦作物的重金属污染情况，收集了我国粮食主产区水稻/小麦-土壤系统中的砷（As）、镉（Cd）、铬（Cr）和铅（Pb）含量，综述了其吸收、转运、积累机制和有效的修复措施.结果表明，我国粮食主产区水稻及小麦籽粒的Cd超标率达31.3%和22.2%，Pb的超标率达26.2%和32.1%，污染情况较为突出；降低As、Cd、Cr和Pb的生物有效性，控制其在水稻/小麦植株中的吸收，能够有效减少籽粒中的积累；土壤-作物系统中重金属的吸收可通过水肥管理、化学改良、植物修复、生物修复和遗传学方法等有效调控，从而实现安全生产.今后，应形成多学科交叉互融的全要素格局来完善我国的土壤污染研究，开发农产品安全生产的污染土壤利用技术，从而更好地保障国家粮食安全生产.

Mechanism of heavy metal uptake and transport in soil-rice/wheat system and regulation measures for safe production

To master the heavy metal pollution in rice and wheat crops from main production regions in China, we collected the data from existing literature and analyzed the concentrations of arsenic (As), cadmium (Cd), chromium (Cr) and lead (Pb) in soil-rice/wheat system, summarized their underlying mechanisms of target heavy metals absorption, transport, and accumulation. In addition, effective remediation measures for safe production were also introduced. The results showed that 31.3% and 22.2% of Cd, 26.2% and 32.1% of Pb in rice and wheat grains are over the value of China National Standard (GB2762-2017). Reducing the bioavailability of As, Cd, Cr and Pb and controlling their absorption in the soil-rice/wheat system could effectively decrease their accumulation in grains. The heavy metals uptake in soils-crop systems can be effectively decreased by water and fertilizer management, chemical modification, phytoremediation, bioremediation and genetic methods to achieve safe production. In the future, we should form a multi-disciplinary and integrated all factor pattern to improve the soil pollution research in China. Furthermore, developing the contaminated soil utilization technology for the safe production of agricultural products, so as to better ensure the national food safety production.