Preliminary Study On The Species Constitution Of Soil Microorganism And Activities Of Soil Enzyme In Larix Gmelinii Forest

In this study,the population structure,numbers of soil microorganisms and soil enzymes in different forest types were studied in Herbage-L.gmelinii virgin forest,Betula-L.gmelinii virgin forest of the primary forest and clear cutting L.gmelinii forest,successive cutting L.gmelinii forest of the disturbed forest in the national forestry ecosystems station of Inner Mongolia Great Xingan Mountains by selective media.The results showed that the quantity of total microorganisms were July>May and September,the quantity of soil microorganisms were gradual lower with the increasing in vertical depth,follow orders:0-10cm layer>10-20cm layer>20-30cm layer.Bacteria isolated from plots belonged to 18 genera, Brevibacterium , Bacillus,Corynebacterium and Micrococcus were main genera; actinomycetes were composed of 8 genera,Streptomyces and Nocardia were the main genera:fungi were composed of 18 genera,Penicillium and Cephalosporium were the dominant genera from the primary forest and disturbed forest.Seasonal variation of soil enzymes in the primary forest are July>May and September.,but the neutral phosphatase is May > July and September,activities of soil enzymes are gradual lower with the increasing in vertical depth,follow orders:0-10cm layer>10-20cm layer>20-30cm layer.The disturbed forest is same to the primary forest.Correlation analysis of soil enzymes and soil microorganisms show that in the primary forest ,the invertase has correlation with actinomycetes and total microorganism (P>0.05), the proteinase has correlation with bacteria, fungi and total microorganism (P>0.05), the acid phosphatase has correlation with fungi (P>0.05), the neutral phosphatase has correlation with fungi and actinomycetes (P>0.05), the alkalinity phosphatase has correlation with bacteria, fungi, actinomycetes and total microorganism (P>0.05).In the disturbed forest, the invertase has very significant positive correlation with actinomycetes (P<0.01), the proteinase has significant positive correlation with bacteria, fungi, actinomycetes and total microorganism (P<0.05), the acid phosphatase has correlation with bacteria, fungi, actinomycetes and total microorganism (P>0.05), the neutral phosphatase has correlation with bacteria, fungi, actinomycetes and total microorganism (P>0.05), the alkalinity phosphatase has very significant positive correlation with bacteria, fungi, actinomycetes and total microorganism(P<0.01).