Dynamics Of Forest Soil Enzymes At Different Successional Stages In The Greater Khingan Mountains

Due to the interference of natural and human factors on the northern forest ecosystem,the number of gradual succession of boreal forests has gradually increased,and the material cycle process and various organic matter contents of different succession stages are not the same.Soil enzymes play an important regulatory role in the process of forest soil material cycling,and have important indicators for the C,N,and P cycles in the northern forest ecology.Therefore,studying the changes in soil enzyme activities is of great significance to the forest ecosystem.In the process of succession,soil enzyme activity will inevitably change to a certain extent.In order to explore the change trend of forest soil enzyme activity and soil enzyme stoichiometry at different succession stages in Daxinganling,this experiment uses space instead of time.In Daxinganling area Field simulation experiments were carried out,and four different succession stages were found,namely grassland,birch forest,birch-larch mixed forest,and larch pure forest.The soil physical and chemical properties and C of the four different succession stages of the plant growth season were determined.,N,P-related changes in the activity of different types of enzymes and their ecological stoichiometric relationships,to explore the change trend of soil enzyme activity in different succession stages,the correlation between soil enzyme activity and soil physical and chemical properties,and the stoichiometric ratio of soil enzymes to provide theoretical support.The following results are obtained through experiments:(1)There is a significant correlation between soil microbial biomass and soil enzyme activity,P-related enzymes have a significant positive correlation with MBC and MBN,and N-related enzyme activities have a significant negative correlation with MBP.(2)P-related enzymes are significantly positively correlated with soil C:P and N:P,and negatively correlated with N-related enzyme activities.MBC:MBN is negatively correlated with C-related enzymes,and positively correlated with P-related enzymes.Related,while MBC:MBP and MBN:MBP are positively correlated with P-related enzymes,MBC:MBN and C:P have a significant negative correlation with(BG+CBH)/(AP+ALP).(3)The soil enzyme activity and other physical and chemical properties in the later stage of succession are more affected by N restriction than in the earlier stage of succession.(4)In the later stages of succession,soil enzyme activities and other physical and chemical properties are affected by more N restrictions.