秸秆不同方式还田对土壤理化性质的影响

Effect of Different Straw Returning Ways on Soil Physical and Chemical Properties

针对东北地区玉米种植面积逐年增加,作为重要有机物料的玉米秸秆还田存在困难,为了探索适合黑土最佳还田方式以及还田量,开展秸秆还田对土壤结构及肥力影响的研究,明确秸秆不同还田方式对提高土壤肥力和改善土壤结构的效果,进行田间试验。结果表明:玉米秸秆耕层混拌1/2还田和1/3还田较其它处理降低土壤容重,增加土壤总孔隙和田间持水量明显,较对照差异显著;秸秆全量还田和秸秆全量还田添加腐解剂处理之间差异不显著。秸秆1/2还田和1/3还田较对照增加>2.000mm土壤粒级团聚体,说明有机物料最佳还田方式有助于土壤大团聚体(>0.250mm)的形成,形成良好土壤结构。秸秆还田各处理均可以增加土壤速效养分,对土壤pH进行调节,并且秸秆还田后大量有机碳源的投入给土壤微生物的生长提供了碳和能源,秸秆还田不同处理微生物量C和微生物量N都相应增加。秸秆耕层混拌1/2还田和1/3还田玉米的生育指标和产量好于其它处理,表明秸秆耕层混拌1/2还田和1/3还田较其它处理方式在改善土壤结构,提高微生物活性及土壤养分,增加作物产量方面表现出优势。

In the northeast China ,maizeacreage has increased year by year ,as an important organic material of maizistraw ,itreturnes difficulty ,in order to explore the best returning way and returning amount to suit black , the effects of straw returningonsoil structure and fertility were researched .The results showed that maizi straw mixed to topsoil ,1/2 and 1/3 returning reduced the soil bulk density than other treatments ,increased the soil total porosity and field water holding capacity significantly ,comparingwith contrast was significant difference ;Between straw full amount returning and straw full amount returning added the decomposing agent ,there was not significant difference .Straw 1/2 and 1/3 returning compared to contrast increasedmore than 2 .000 mm fraction aggregate ,the best returning way of soil organic material improved large aggregate （〉0 .250 mm） and the formation of good soil structure .Each treatment of straw returning could increase soil available nutrient and adjust soil pH ,after straw returning ,a considerable investment of organic carbon source provided carbon and energy sources for the growth of the soil microbial ,microbial biomass carbon and microbial biomass nitrogen were increased in straw returning different treatment .1/2 and 1/3 returning in straw mixed to topsoil ,the maizi growth indexes and yield was better than other treatment ,showed that 1/2 and 1/3 returning in straw mixed to topsoil improved soil structure than other treatment ,improved the microbial activity and soil nutrient ,showed the advantage to increase crop yields .