Quantitative Characters Of Soil Microbe Of Different Forest Types In Wenchang District Of Hainan Island And Their Relation To Soil Factor

Right now,the study of the quantitative characters of soil microbe of five forest types in coastal terrace and their relation to soil factor lack of all around research all the time.Coastal terrace is an important region the coastal shelter-forest system.In the soil parent material,soil type and climate conditions are basically the same,dilution-plate method was used to study the quantitative characters of soil microbe and their relation to soil factor of palm forest,Acacia auriculiformis,Horsetail beefwood,secondary forest and artificial regeneration forest in coastal platform of Wenchang,Hainan.The study would be aimed at discussing the distribution characteristics of soil microbial numbers,analysing the relation between soil microbe and soil factor and guiding the sustainable management and provides a reference for the protection forests.The main results are as follows:(1)Due to the influence of plants,soil nutrients and artificial disturbance,the number of soil microorganisms in different forest types was different.In the five kind of forest types.The population of bacteria was the biggest in the palm forest(3144.67×104cfu/g),that is 1.99 times more than Mangium,2.56 times more than Casuarina equisetifolia,1.32 times more than Secondary forest and 2.85 times more than Human erythropoietin update secondarythe respectively.The population of fungi was the biggest in the Mangium(46.12×104cfu/g),that is 2.61 times more than Palm forest,1.06 times more than Secondary forest,1.41 times more than Human erythropoietin update secondary and 1.37 times more than Casuarina equisetifolia respectively.The population of actinomycetes was the biggest in the Palm forest(3144.67×104cfu/g),that is 1.54 times more than Secondary forest,1.62 times more than Human erythropoietin update secondary,3.36 times more than Mangium and 1.42 times more than Casuarina equisetifolia respectively.(2)The soil microbial diversity index is different from the quantity of soil microorganisms.Mainly for Human erythropoietin update secondary(0.58)>Casuarina equisetifolia(0.57)>Secondary forest(0.41)>Mangium(0.40)>Palm forest(0.39).The outcome depends on evenness of the quantity of soil microorganisms.Besides the quantity of Fungi of Palm forest,Secondary forest and Human erythropoietin update secondary,the vertical quantitive distribution of soil microorganism has a degressive tendency when the depth increased.The number of soil microorganisms was presented significant seasonal variation trend in the five forest types.Total of microbe in June is 1.89?4.14 times and 2.74?9.35 more than in December and March respectively.And the population of soil bacteria in the rainy season is much more than in the low-temperature season and the dry season.The quantity of actinomycetes presents low-temperature season>rainy season>dry season.The quantity of fungi is down from December to June in five forest types.(3)The contents of soil nutrients in Palm forest is better than other forest types,besides the contents of available potassium and nitric nitrogen.There are different relation between the quantity of soil microorganisms and the contents of soil nutrients.Organic carbon and total nitrogen are the major factors affecting soil microbial quantity in Palm forest and Human erythropoietin update secondary.Total nitrogen and pH value are the major factors affecting soil microbial quantity in Mangium.Total nitrogen and total phosphorus are the major factors affecting soil microbial quantity in Casuarina equisetifolia.(4)There is a significantly positive correlation(p<0.01)between the quantity of soil microorganisms and Soil Organic C and Active Organic C,besides the quantity of fungi in Palm forest and Human erythropoietin update secondary.So the quantity of soil microorganisms can be a useful standard in evaluating the changing of Soil Organic C.The differences in the plant cover,soil physical and chemical properties and the man-made disturbance influence in five forest types result in variability of the correlation between Soil Organic C and soil microorganisms.LFOC and EOC are the major factors affecting soil microbial quantity in Palm forest.EOC and DOC are the major factors affecting soil microbial quantity in other forest types.