蚯蚓活动和秸秆施用方式对土壤生物学性质的动态影响

通过实验室短期培养研究接种蚯蚓和有机物不同施用方式(混施与表施)对土壤微生物类群、土壤微生物量以及呼吸强度等土壤生物学性质的影响。结果表明,接种蚯蚓对土壤可培养酵母菌、细菌数量和土壤底物诱导呼吸强度有明显促进作用。最高增幅分别达到相应未接种蚯蚓处理的5.18,8.88,2.50倍。蚯蚓活动对土壤微生物量及真菌数量的影响受到秸秆施用的影响:在混施和不施秸秆的处理(SRME、SE)中显著抑制丝状真菌数量;在混施秸秆处理中蚯蚓活动降低了SMBC含量。秸秆的施用方式对土壤微生物性状也有较大影响。混施秸秆处理中,土壤酵母菌、细菌数量、土壤微生物量和土壤呼吸强度增加也最为明显,而丝状真菌数量的增加幅度却不如表施秸秆处理。各处理土壤微生物量碳随时间变化趋势比较一致,呈现先降(第4周)后增的变化趋势,其他测定项目没有一致的随时间变化的规律。方差分析表明秸秆施用对土壤微生物量氮和可培养微生物数量变化的贡献最大,分别达到96.5%(SMBN)、77.9%(细菌)、69.4%(酵母菌)和85.3%(丝状真菌)。并且时间、秸秆和蚯蚓因子间存在强烈交互作用。

Dynamic Effects of Soil Biological Properties Under Earthworm Inoculation and Organic Matter Application

This study was conducted in lab to examine the effect of organic matter application and earthworm inoculation on soil biological properties dynamics.Six treatments included: S(CK,without residues and earthworms);SE(only earthworms);SRC(only residues covered);SRCE(residues covered and earthworms);SRM(residues mixed) and SRME(residues mixed and earthworm).It showed that earthworms strongly increased the amount of yeast and bacteria,and also the substrate induced respiration of soil,with the biggest increase of about 5.18,8.88,2.5 times compared to the treatments without earthworms.The effect of earthworms activities on the soil biological properties was affected by the residues supplies,the earthworms activities significantly decreased the amount of filamentous fungi in mixed residues and without residues,and significantly decreased the SMBC content in mixed residues.The way residues supplied had a different effect on soil biological properties:With mixed residues,the promotion was highest in the amount of yeast and bacteria,soil microbial biomass(SMB) content and substrate induced respiration,while the biggest increase in filamentous fungi was in residues covered treatment.In all items determined,only the trend of SMBC changes that decreased before four weeks and increased later was consistent in all treatments,while the other items determined.The results of variation analysis demonstrated that residues supplies explained most of the variations in SMBN content and the amount of soil microbial biomass,explaining about 96.5% in SMBC,77.9% in bacteria,69.4% in yeast,and 85.3% in filamentous fungi.Further,there was strong interaction among the earthworms,residues supplies,and time.