冻融过程对苹果梨园土壤微生物量碳、氮、磷含量变化的影响

Effects of Freeze-thaw on soil microbial biomass in Apple-pear Orchard

延边地区是苹果梨生产的优生区,且经历季节性的冻融过程,有别于国内其它地方的果园生态系统。为分析冻融作用对延边地区苹果梨园土壤微生物量的影响,进一步指导苹果梨园土壤管理,对延边朝鲜族自治州龙井市季节性冻融前后栽植年限分别为11、25、40、63年的苹果梨园不同土层(0~20、20~40、40~60 cm)微生物量碳、氮、磷进行了测定。结果表明:不同栽植年限果园土壤经季节性冻融后,微生物量碳、氮、磷含量在各个土层总体呈上升趋势。整体来看,0~40 cm层次的微生物量碳含量在栽植年限为11、25年果园中受季节性冻融作用影响大于40和63年果园;微生物量氮含量在4种年限果园土壤中均受季节性冻融作用的显著影响;微生物量磷含量在栽植年限11和40年的果园土壤中受季节性冻融作用影响大于25、63年。对比3个土层,土壤微生物量碳、氮、磷含量在0~20、20~40 cm受季节性冻融作用影响均大于40~60 cm土层。

Yanbian is an outstanding area for the apple-pear production.Unlike other areas,the orchard ecosystem of Yanbian experiences a seasonal freeze-thaw.To guide the management of apple-pear orchards,this study investigated the effects of freeze-thaw on soil microbial biomass of apple-pear orchards in Longjing City,Yanbian Korean Autonomous Prefecture through determining microbial biomass C,N and P contents in different soil layers(0-20 cm,20-40 cm,and 40-60 cm)before and after freezing and thawing,which the orchards were planted applepear for 11,25,40 and 63 years.The results showed that the contents of soil microbial biomass C,N and P in orchards with different years of cultivation increased after seasonal freezing and thawing.In the soil of 0-40 cm,the contents of soil microbial biomass C in 11-and 25-years-old orchards were higher than those in 40-and 63-year-old orchards.The contents of soil microbial biomass N were greatly affected by freeze-thaw in the four orchards with different years of cultivation.The contents of soil microbial biomass P in 11-and 40-years-old orchards were greater than those in 25-and 63-years-old orchards.Among three different soil layers,the contents of microbial biomass C,N and P in 0-20 cm and 20-40 cm were higher than those in 40-60 cm.