不同有机物及其堆肥与化肥配施对小麦生长及氮素吸收的影响

采用15N示踪技术,选用水稻土和灰潮土在宜兴进行小麦盆栽试验,研究了稻草、猪粪及其堆肥与化肥配施对作物生长及氮素吸收的影响。结果表明,在水稻土和灰潮土上,不同有机物及其堆肥与化肥配施分别比单施化肥增产4.46%～24.82%和1.01%～20.53%,稻草堆肥和猪粪堆肥配施化肥处理籽粒产量分别高于稻草和猪粪直接与化肥配施处理。稻草和猪粪堆肥后更利于作物吸收氮素,增加植物体内15N累积。两种土壤上15N回收率表现为相同配比的堆肥处理未堆肥处理单施化肥处理。随着小麦生育期的推进,土壤微生物量氮和矿质态氮含量均呈下降趋势,稻草和猪粪处理的微生量氮含量始终高于稻草堆肥和猪粪堆肥处理。有机无机肥配施处理土壤矿质态氮在小麦生育前期低于单施化肥,成熟期则高于单施化肥。整个生育期中,稻草堆肥和猪粪堆肥处理土壤矿质态氮含量分别高于稻草和猪粪处理。因此,有机物堆肥后与化肥配施更有利于提高产量,促进作物对氮素的吸收利用。

Effects of combined application of inorganic fertilizer with straw and pig slurry and their compost on wheat growth and nitrogen uptake

Effects of combined application of inorganic fertilizer with straw, pig slurry, straw compost and pig slurry compost on wheat growth and nitrogen uptake were studied in paddy soils and gray alluvial soils. A pot experiment was carried out in paddy soils and gray alluvial soils in Yixing based on ¹⁵N isotope tracer. The results show that compared to the inorganic N fertilization treatments, the combined applications of organic and inorganic fertilizers increase wheat yields by 4.46%-24.82% and 1.01%-20.53% in paddy soils and gray alluvial soils, respectively. Wheat yields under the combined applications of the straw compost and the pig slurry compost are higher than those of the combined applications of straw and pig slurry, respectively. The combined applications of the straw compost and the pig slurry compost stimulate N uptake and improve N accumulation of wheat. The treatments of the straw compost and the pig slurry compost have the highest ¹⁵N recovery rates, while the ¹⁵N recovery rates of the inorganic N fertilization the treatments are the lowest. Soil microbial biomass nitrogen under the combined application of straw and pig slurry is always higher than that under the combined application of the straw compost and the pig slurry compost during wheat growth season. At the tillering stage, soil mineral nitrogen under the inorganic N fertilization treatment is higher, and it is lower in the later growing stages. During the whole growing period, soil mineral nitrogen amounts under the combined applications of the straw compost and the pig slurry compost are higher than those under the combined applications of straw and slurry. In summary, the combined application of the composts and inorganic fertilizer is more conducive to improving crop yields and plant N uptake.