不同改良措施对银川平原盐碱地土壤微生物区系的影响

为了明确不同改良措施对银川平原盐碱地土壤微生物的影响,研究了秸秆、有机肥、烟气脱硫废弃物、盐碱地改良剂对银川平原盐碱地土壤微生物区系的影响及其与土壤微生物多样性、土壤性质之间的相关关系。结果表明:脱硫废弃物处理能够显著降低土壤真菌数量,降低幅度6.22%～37.81%,改良剂和有机肥处理能够增加土壤细菌数量,0～20cm增加的幅度分别为6.25%～94.35%和12.91%～93.64%。脱硫废弃物、有机肥和秸秆处理与对照相比能够增加土壤放线菌数量,3个处理在整个生长季增加0～20cm土壤放线菌数量的幅度分别为1.97%～7.35%、20.58%～48.11%和11.25%～37.44%。各改良措施增加了土壤微生物群落对碳源的利用能力,0～20cm土壤依次表现为秸秆>有机肥>脱硫废弃物>改良剂>对照。各处理土壤细菌、微生物总数与土壤pH值、全盐含量、容重呈显著负相关关系(P<0.05),与土壤孔隙度呈极显著正相关关系(P<0.01),盐碱地土壤容重是土壤细菌、微生物总数和土壤微生物碳源利用能力的最大限制性因子。

Effect of Different Soil Improvement Measures on Microbial Flora in Saline-alkali Soil in Yinchuan Plain

In order to grasp the impact of improvement measures on saline-alkali soil microbes of Yinchuan plain,a field experiment was conducted to study the effects of straw,organic fertilizer,flue gas desulfurization(FGD) waste and saline-alkali soil amendment on soil microflora and microbial community diversity,and the correlation between soil microbial diversity,microorganisms number,and soil properties in saline-alkali soil in Yinchuan plain.The results showed that desulfurization waste treatment significantly reduced the number of soil fungi by 6.22% to 37.81%,while amendment and organic fertilizer processing increased the number of soil bacteria,by 6.25% to 94.35% and 12.91% to 93.64% in 0-20 cm,respectively.Compared to the control,desulfurization waste,organic fertilizer and straw treatment increased the number of soil actinomycetes,by 1.97% to 7.35%,20.58% to 48.11% and 11.25% to 37.44%,respectively,in 0-20 cm throughout the growing season.The four improvement measures increased the utilization capacity of carbon source by soil microbial community,with the effect order in 0-20 cm soil by straw>organic fertilizer>FGD waste>aline-alkali soil amendment>control.The significant negative correlation existed between the amount of bacteria,total microbes and soil pH,total salt content,bulk density,while the highly significant positive correlation existed between the amount of bacteria,total microbes and soil porosity.