基于农田土壤重金属污染风险筛选值的畜禽粪污农田承载力估算

Estimation on farmland carrying capacity for livestock and poultry manure based on risk screening values for farmland soil heavy metal contamination

关键词:  畜禽粪污农田承载力  重金属  污染风险筛选值  环境容量

Key words:  land carrying capacity for livestock and poultry manure  heavy metals  risk screening values  environmental capacity

摘要:

针对有机肥施用中，畜禽粪便中重金属造成农田土壤污染的问题，对重金属在养殖业-种植业生产系统中的流动过程进行分析，建立基于农田土壤重金属污染风险筛选值的畜禽粪污农田承载力估算模型，以黑龙江农垦和新疆生产建设兵团的养殖业-种植业生产系统为研究对象，计算获得相应的畜禽粪污农田承载力。结果表明:1)在水稻、玉米和大豆种植情况下，黑龙江农垦每hm²农田可承载的猪当量分别为37、21和21 头；在棉花、小麦和玉米种植情况下，新疆生产建设兵团每hm²农田可承载的猪当量均为67 头。2)在畜禽粪便有机肥施用过程中，黑龙江农垦和新疆生产建设兵团农田土壤重金属污染风险防控应以Cd、Cu和Zn为主。建议未来注重防控农田土壤酸化和以磷肥途径的Cd输入，并根据各自实际畜禽养殖生产现状与农田土壤重金属本底值，建立地方标准控制畜禽粪便有机肥中Cu和Zn的质量分数。

Abstract:

Aiming at the problem of farmland soil heavy metal pollution caused by livestock and poultry manure during the manure application. The flow process of heavy metals in the crop-farm animal production system was analyzed. Based on risk screening values for farmland soil heavy metal contamination, an estimation model on farmland carrying capacity for livestock and poultry manure was established. The crop-farm animal production system in Heilongjiang Land Reclamation Area(HLRA)and Xinjiang Production and Construction Corps(XPCC)were selected as study cases. Under the long-term risk screening values of soil, the farmland carrying capacity for livestock and poultry manure was calculated. The results showed that: 1)In HLRA, under t rice, maize and soybean cultivation, the carrying capacities of swine equivalent were respectively 37, 21 and 21. In XPCC. Under cotton, wheat and maize cultivation, the carrying capacitys of swine equivalent was 67. 2)Cd, Cu and Zn should be taken into account firstly to prevent heavy metal pollution in HLRA and XPCC during the manure application. In the end of this study, it is recommended to focus on preventing farmland soil acidification and Cd input. Based on livestock production status and soil heavy metals background values, local standards are established to control heavy metals in manure