生物有机肥对潮土物理性状及微生物量碳、氮的影响

目的]研究生物有机肥对潮土不同土层土壤物理特性及微生物碳氮的影响,为生物有机肥在土壤改良、水土保持和促进设施农业可持续发展等方面提供科学依据。方法]采用田间小区试验的方法,研究生物有机肥对潮土0—15和15—30cm土层土壤水力学性质、土壤团聚体及微生物量碳、氮的改善效果,其中生物有机肥施用量分别为0,10,20t/hm~2。结果]施用生物有机肥可显著降低土壤容重,提高土壤孔隙度和各水力学指标,其中土壤容重降低了10.37%~19.26%,田间持水量和饱和导水率提高了13.12%~32.25%和37.28%~67.11%;生物有机肥可提高土壤大团聚体含量和平均质量直径,降低分形维数;生物有机肥提高了土壤微生物量碳、氮含量,增幅分别为33.66%~52.67%和11.52%~22.64%;土壤物理特性与微生物量碳、氮具有明显相关性。结论]生物有机肥可有效改善潮土土壤结构和水力学特性,增加土壤蓄水供水能力,提高土壤大团聚体含量、稳定性和微生物量碳、氮含量。

Effects of Bioorganic Fertilizer Application on Soil Physical Properties and Microbial Biomass Carbon and Nitrogen in Fluvoaquic Soil

Objectives] To study the effects of bioorganic fertilizer application on soil physical properties and microbial biomass carbon and nitrogen in different soil layers, in order to provide scientific data for applying bioorganic fertilizer in soil improvement, soil and water conservation and the sustainable development of agricultural facilities.Methods] Field soil tests were conducted to study the effects of bioorganic fertilizers on soil hydraulic properties, aggregate and microbial biomass carbon and nitrogen in 0-15 and 15-30 cm soil layers of fluvoaquic soil. The application rates of bioorganic fertilizer were 0, 10 and 20 t/hm², respectively.Results] The application of bio-organic fertilizer could significantly reduce soil bulk density, increase soil porosity and hydraulics indexes. The soil bulk density decreased by 10.37%~19.26%, the field capacity and saturated hydraulic conductivity increased by 13.12%~32.25% and 37.28%~67.11%, respectively. Bioorganic fertilizer could also increase the content and average mass diameter of soil aggregates and reduce the fractal dimension of aggregates. Application of bio-organic fertilizer could increase the content of soil microbial biomass carbon and nitrogen by 33.66%~52.67% and 11.52%~22.64%, respectively. Soil physical properties had a significant correlation with microbial biomass carbon and nitrogen.Conclusions] Application of bioorganic fertilizer can effectively improve the structure and hydraulic characteristics of fluvoaquic soil, increase the capacities of soil water storage, improve soil aggregate content, stability and microbial biomass carbon and nitrogen content.