中国农业科学Issue(23)：4669-4677,9.DOI:10.3864/j.issn.0578-1752.2015.23.008
长期施肥对紫色水稻土团聚体中有机碳和微生物的影响
Influence of Long-Term Fertilization Managements on Organic C and Microorganism in Different Aggregates in Purple Paddy Soil
摘要
Abstract
[Objective] Soil microorganisms play a critical role in the maintaining soil fertility, soil health and crop productivity. Soil microbial biomass carbon (C) concentration in different sizes of aggregates and aggregate distribution were studied in neutral purple paddy soil under long-term fertilization management. The aim of the study is to elucidate the relationship between long-term fertilization and microbial biomass dynamics in aggregate, in order to evaluate the influence of different fertilizer managements on evolution of soil fertility.[Method] Four treatments were conducted this research (1)CK;(2)NPK;(3)S;(4)NPK+S. Soils were sampled at 0-20 cm depth.Wet-sieving method was used to determine aggregate distribution of a neutral purple paddy soil after long-term fertilization management for 22 years. Soil microbial biomass C concentration and activity were determined at all aggregate levels.[Result]Long-term fertilization management after 22 years indicated that soil large aggregate content with sizes of>0.25 mm was significantly increased in treatments with inorganic nitrogen, phosphorus, and potassium fertilizer (NPK), with rice straw return (S), and with both (NPK+S), compared to the control. The increase was highest in NPK+S treatment where the aggregate stability was also shown to be the greatest, thus indicating the importance of inorganic fertilizer and organic residues in the formation and stability increases of large aggregate in purple soil. Fertilization increased aggregate stability and soil organic C content significantly, the increase was highest in S and NPK+S, indicating the importance of straw returning in the increase of aggregate stability and soil organic C. Long term fertilization changed the distribution of soil nutrition and microbial activity in soil aggregates. Further, soil organic C and microbial biomass C concentration varied in different aggregate sizes. In large water-stable aggregate (2.00-1.00 and 1.00-0.25 mm), organic C concentration, soil respiration rate and metabolic quotient were greater than in small aggregate (<0.25 mm).[Conclusion]Aggregate larger than 0.25 mm had the greatest proportion of soil organic C and microbial biomass C, while microbial activity was greatest in 1.00-2.00 mm. Under such agroecosystem, long-term application of inorganic NPK fertilizer together with rice straw return greatly increased the proportion of large water-stable aggregate and the concentration of soil organic C and microbial biomass C. It is therefore an effective land management in improving aggregates distribution, increasing soil microbial function and productivity in purple paddy soil.关键词
长期施肥/水稻土/团聚体/微生物量/异质分布Key words
long-term fertilization/paddy soil/aggregate/microbial biomass/hetergeneous distribution引用本文复制引用
陈轩敬,梁涛,赵亚南,张跃强,石孝均..长期施肥对紫色水稻土团聚体中有机碳和微生物的影响[J].中国农业科学,2015,(23):4669-4677,9.基金项目
国家科技支撑计划（2012BAD05B03）、国家公益性行业（农业）科研专项（201003013）、国家自然科学基金 （）
