不同林龄下红松林土壤酶活性和微生物生物量对土壤理化性质的响应OA

Taking the soil at five soil depths(0-10,10-20,20-40,40-60,60-100 cm)of Korean pine forest aged 8,25 and 68 years in Wutai mount scenic area,Shanxi province as the research object,two factor variance analysis,redundancy analysis and Pearson correlation analysis were used to determine the soil physical and chemical properties,enzyme activities and microbial biomass under different forest ages and soil layers.The results showed that the overall activities of soil β-1,4-glucosidase,β-xylosidase,urease,cellulase,acid protease,and acid phosphatase were the highest under the three forest ages of 68 years,and gradually decreased with increasing soil depth.The overall performance of soil microbial biomass carbon(MBC)and microbial biomass nitrogen(MBN)content under three forest ages was ranked as 68 years＞25 years＞8 years forest age,and MBC and MBN content gradually decreased with increasing soil depth.Redundancy analysis revealed that soil total organic carbon content,total porosity,field water holding capacity,bulk density,pH,capillary pores,capillary water holding capacity,and nitrogen phosphorus ratio were key soil indicators that caused changes in soil enzyme activity.Soil bulk density,pH,carbon phosphorus ratio,and carbon nitrogen ratio were key soil indicators that affected changes in soil microbial biomass.Soil bulk density,pH,total organic carbon,total nitrogen and total phosphorus contents were key soil indicators that jointly affected soil enzyme activity and microbial biomass.Therefore,it was recommended to appropriately increase soil nutrient management for low forest age in the future artificial forest management process,alleviate soil nutrient limitations,and improve soil quality.