有机肥替代部分化肥对稻麦轮作系统产量及土壤微生物区系的影响

[目的] 本文旨在研究不同有机肥替代部分化肥对稻麦轮作系统产量及其构成因素、土壤微生物区系的影响,为找到合适的施肥措施来提高作物产量,培育高产土壤微生物区系提供理论依据。[方法] 以江苏省金坛市的长期肥料试验点为研究对象,设置6个施肥处理:不施肥(CK),常规氮、磷、钾化肥(NPK),3000 kg？hm-2猪粪有机肥替代30%常规化肥施用量(NPKM1),6000 kg？hm-2猪粪有机肥替代50%常规化肥施用量(NPKM2),1800 kg？hm-2猪粪有机无机复合肥替代50%常规化肥施用量(NPKMOI1),3600 kg？hm-2猪粪有机无机复合肥替代70%常规化肥施用量(NPKMOI2)。测定水稻、小麦的有效穗数、每穗粒数、千粒质量、理论产量和实际产量;并利用氯仿熏蒸-硫酸钾浸提法和高通量测序测定土壤微生物生物量及微生物群落结构。[结果] 与NPK处理相比,猪粪有机肥(NPKM1、NPKM2)和猪粪有机无机复合肥(NPKMOI1、NPKMOI2)替代部分化肥对水稻和小麦的产量构成因素、理论产量和实际产量无显著降低,且均能提高土壤微生物生物量碳、氮。NPKMOI1和NPKMOI2处理能够增加土壤细菌丰富度、多样性和均匀度指数,显著改变土壤细菌区系,且这种改变随着化肥替代量的增加而变大。[结论] 3600 kg？hm-2猪粪有机无机复合肥替代70%常规化肥施用量处理能够提高作物产量,是一种具有培育高产土壤微生物区系潜力的施肥措施。
[Objectives] The objective of this study was to investigate the effects of different organic fertilizers partial substitution for chemical fertilizer on crop yield and its components,and soil microbiome in a rice-wheat cropping system,and find out the suitable fertilizer regime to increase crop yield and provide the theoretical basis for establishing high-productivity associated soil microbiome.[Methods] With the long-term fertilizer experimental site located in Jintan,Jiangsu as the research site,six fertilizer regimes were included in this study:no fertilizer(CK),conventional dosage of chemical fertilizer (NPK),3 000 kg？hm-2 pig manure organic fertilizer substituted 30% of chemical fertilizer (NPKM1),6 000 kg？hm-2 pig manure organic fertilizer substituted 50% of chemical fertilizer (NPKM2),1 800 kg？hm-2 pig manure organic-inorganic compound fertilizer substituted 50% of chemical fertilizer(NPKMOI1),and 3 600 kg？hm-2 pig manure organic-inorganic compound fertilizer substituted 70% of chemical fertilizer (NPKMOI2). The number of productive spikes,number of grains per spike,thousand grains weight,theoretical yield,and actual yield of rice and wheat were measured,respectively. Soil microbial biomass and soil microbiome were determined by chloroform fumigation-K2SO4 extraction method and high-throughput sequencing.[Results] Compared to the NPK treatment,pig manure organic fertilizer (NPKM1,NPKM2) and pig manure organic-inorganic compound fertilizer(NPKMOI1,NPKMOI2)substituted partial chemical fertilizer had no significant decline in rice and wheat yield and their components,and enhanced soil microbial biomass carbon and nitrogen. NPKMOI1 and NPKMOI2 treatments increased soil bacterial richness,diversity and evenness,and markedly shaped the soil bacterial community,and such shifts were increased with the increase of substitution amount of chemical fertilizer.[Conclusions] The treatment that 3 600 kg？hm-2 pig manure