有机肥部分代替无机肥条件下早稻稻田氮素动态变化

为了研究稻田氮素造成面源污染的成因,选出适宜当地水稻种植施肥模式,通过不同种类的农村常用有机肥部分代替无机肥的配比,分析稻田氮素动态变化.结果表明;NH4+-N的损失以地表径流为主,NO3--N主要通过渗漏作用造成地下水污染;不合理的有机无机配方肥,也会造成严重的面源污染;不同腐熟程度的有机肥在氮素的损失方式上不同,新鲜猪粪在渗漏作用和地表径流两种氮源损失方面都比较严重,土壤中NO3--N平均含量达到13.59 mg/kg,居6个处理最高水平,地表水中全时期NH4+-N总量达到5.65 mg/L,仅低于纯化肥处理.猪粪堆肥地表水中全时期NH4+-N总量达到4.52 mg/L看出,通过地表径流的损失在3种有机肥处理中表现最好,且土壤中NO3--N含量平均0.56 mg/kg,因此通过渗漏造成的损失处于6个处理最低水平.沼渣沼液地表水中全时期NH4+-N总量达到4.84 mg/L,土壤中NO3--N含量平均为2.87 mg/kg,认为沼渣沼液主要以地表径流的损失方式为主,且通过渗漏造成的氮源损失略低于纯化肥处理.通过实验研究可以发现,猪粪堆肥可作为适宜水稻种植的有机肥.

Dynamic Change of Nitrogen in Early Rice Paddy Field on the Condition of Organic Fertilizer Instead of Part of the Inorganic Fertilizer

In order to study reason of widespread pollution caused by nitrogen in paddy field, dynamic change of nitrogen with different forms were analyzed by using organic and inorganic fertilizer with different ratio, according to local fertilization model suitable for rice cultivation. The results showed that, pig manure compost was a proper organic fertilizer for rice cultivation. NH4+-N losed by surface runoff, NO3--N by leakage. It could cause severe widespread pollution when manure and inorganic fertilizer with unreasonable ratio was mixed utilized. The manner of nitrogen loss differed in rotten degree of organic fertilizer. Nitrogen loss of fresh pig manure, e.g. leakage and surface runoff, was severe correspondingly. The average amount of NO3--N in soil reach the highest level with 13.59 mg/kg in six treatments, while the total amount of NH4+-N, up to 5.65 mg/kg, was lower slightly than that with fertilizer treatment. The total amount of NH4+-N in surface water after pig manure compost treatment reached 4.52 mg/L, and the average amount of NO3--N in soil amounted to 0.56 mg/kg. In contrast to the six treatments, the loss of nitrogen in pig manure compost by leakage was the lowest level. The NH4+-N amount of surface water with ad residues treatment reached 4.84 mg/L, while the average NO3--N content was 2.87 mg/L, indicating that nitrogen loss way of ad residues was surface runoff primarily, and the nitrogen loss by leakage was lower slightly than fertilizer treatment.