秸秆还田对水稻土微生物影响的研究进展

Advanceson Impact of Straw Returning on Microorganisms in Paddy Soil

水稻土是我国主要农业土壤类型之一。水稻土的发生发育过程在"土壤-微生物-水稻"相互作用的系统中进行,生态系统功能很大程度上受微生物生物量、多样性和功能等特征所影响。施肥可影响土壤养分循环和土壤质量,同时也影响土壤微生物活性及其群落多样性。有机肥肥效持久,可增加土壤地力,符合现代可持续发展的理念。有机肥代替化肥已逐步成为国家需求之一。其中,秸秆是稻田重要的有机资源,直接还田是最经济可行,易于推广操作的综合利用方式。鉴于土壤微生物在稻田生态系统中的重要性和有机肥施用对农田土壤地力可持续性的影响,本文主要论述了当前国内外在有机肥料施用,特别是秸杆还田对水稻土中微生物生物量、群落结构、多样性和功能影响以及微生物生态效应研究的进展,并进一步展望了水稻土中主导秸秆降解的微生物群落在时空尺度上的变异性。

Paddy soil is one of the main agricultural soils in China.The occurrence and development process of paddy soil is carried out in an interactive system of soil-microbe-rice.And the function of this ecosystem is affected,to a large extent,by microbial biomass,microbial diversity,microbial function and so on.As a regular management measure,fertilizationaffects soil nutrient cycling and soil quality,as well as microbial activity and community diversity,and playsan irreplaceable role in all agricultural activities.Among various fertilizers,organic fertilizer with its enduring efficiency,when being applied to soil,improves soil physical and chemical properties,and stimulates microbial activities,so that the relative high soil fertility is hopefully to be maintained,which conforms to the modern concept of sustainable development.Although chemical fertilizer has a quick effect,a large number ofits utilization for a long period decreasesthe content of soil organic matter,and causesthe deterioration of soil physicochemical properties.It is gradually replacedby organic fertilizer.Strawhasrich mineral nutrients andis an important natural organic resource in the paddy field,but its utilization so far is lack of modern scientific and technological means,resulting in a large area of combustion,which not only pollutes the air,but also poses a serious threatto the ecological environment.At present,directly returning to the fieldavoids waste of resources and environmental pollution,and is also the most economical and feasible comprehensive utilization method which is quite easy to popularize and operate.In view of the importance of microorganisms in paddy ecosystem and the influence of organic fertilizer on maintaining soil productivity,this paper mainly discussed domestic and foreignresearch progresses about the impact of organic fertilizers,especially straw returning on the microbial biomass,community structure,microbial diversity,microbial function and ecological effect in the paddy soil.Furthermore,we looked forward about the variability of microbial communitiesdominant in the straw degradation on the spatial and temporal scales,so as to provide a theoretical guidance for the application of organic fertilizer and theresources-like management in the farmland.