黄土区典型林地土壤养分-酶活性-微生物多样性差异分析OA

activities and microbial diversity,which can provide theoretical basis for the improvement of soil function and the selection of suitable tree species in the study area from the perspective of soil improvement by forest land.[Method]This study selected 5 typical forest stands(Robinia pseudoacacia pure forest,Pinus tabulaeformis pure forest,Platycladus orientalis pure forest,Pinus tabulaeformis-Robinia pseudoacacia mixed forest,Quercus wutaishanica-Populus davidiana mixed forest)in the loess area of Western Shanxi,and used the barren grassland as the control,to determine the characteristics of soil nutrients,enzyme activities and microbial diversity in different forests,and to analyze the interrelationships among soil nutrients,enzyme activities and microbial diversity by combining the high-throughput sequencing method,one-way analysis of variance,redundancy analysis,etc.This study also analyzed the relationship between soil nutrients,enzyme activities and microbial diversity of different forests.The relationship between soil nutrients,soil enzyme activity and microbial diversity was analyzed by combining high-throughput sequencing and redundancy analysis.[Result](1)The soil nutrients of forest land were better than those of barren grassland,and the contents of total nitrogen(TN)and organic matter(SOM)in the Pinus tabulaeformis-R.pseudoacacia and Q.wutaishanica-Populus davidiana mixed forests were significantly higher than those in the other pure forests(P＜0.05).(2)Soil β-glucosidase(BG),leucine aminopeptidase(LAP),and alkaline phosphatase(ALP)activities were the highest in Q.wutaishanica-Populus davidiana mixed forests,and soil β-N-acetylamino-glucosidase(NAG)activity was the highest in Pinus tabulaeformis pure forest.(3)ACE,Chao1 and Shannon's alpha diversity indices of soil bacteria were generally high,but mixed forest creation significantly enhanced the species richness of fungal communities(P＜0.05).(4)Soil enzyme activities were significantly correlated with soil TN,ANC,NNC,AP and SOM contents(P＜0.05),and soil microbial diversity was were closely correlated(P＜0.05).Soil NAG and ANC were the key drivers of microbial communities.[Conclusion]The comprehensive study showed that mixed forests exhibited significant positive effects on soil nutrient accumulation,enhanced enzyme activities and increased fungal diversity compared with pure forests and barren grasslands.Therefore,based on the perspective of soil improvement by forest stands,it is recommended that a mixed forest configuration with deciduous broadleaf or coniferous broadleaf species as the core should be prioritized in the vegetation restoration and reconstruction of loess area.[Ch,4 fig.6 tab.32 ref.]