Soil Microbial Community Structure And Function Under Plantations Of Different Tree Species

This research was carried out in Tingxi Forest Farm in Xiamen City,Fujian Province.By measuring the different tree species forests soil properties,plant characteristics,microbial biomass,the differences between the community and the function,analysis the influence of tree species on soil properties,microorganism and enzyme activity.The main conclusions are as follows:(1)By phospholipid fatty acid analysis we can found that eight species of plantation forests soil microbial fatty acid content exi(?)significant differences on the whole show Nitrogen fixation trees>broad leaved tree species>conifer tree specie but conifer fokienia hodginsii phospholipid fatty acid content and nitrogen-fixing trees relatively close.In addition to the fokienia hodginsii Nitrogen fixation trees G+:G-is significantly higher than hardwood species and conifer,which show that nitrogen-fixing trees by the low degree of external stress.Fungal community of differences between different tree species mainly comes from the saprophytic fungi which caused the differences of F/B.Principal component analysis show that eight tree species of significant differences between microbial community structure,especially the contrast between the different types of trees,Nitrogen fixation trees microbial community structure and the most significant difference coniferous and broad leaved tree species The results showed that six kinds of enzyme activity of different tree species have a significant impact.Among them the conifer CBH activity is highest which is significantly higher than Phoebe bournei?Schima superba?Acacia mangium show no significant difference between other species.AP?NAG??G?PPO and PER of this five kinds of enzyme activity were the highest nitrogen-fixing trees.(2)Forest soil properties and plant characteristics under different tree species have significant effects on microbial community structure and function.pH,soil available potassium in soil properties have a significant influence on microbial community DON and SWC is also has an important effect on microbial community but did not reach significant level.Soil enzyme activity is mainly affected by the DOC and DON in soil properties,this may mainly because of the study area soil quality is poorer.The characteristics of the plant leaf,litter and root N content and C/N and enzyme activity significantly correlated which shows that the tree species mainly by its own characteristics affect soil properties and enzyme activity.(3)Different species of plantation forests soil properties such as carbon,nitrogen content,soluble organic carbon and nitrogen were significant differences,Nitrogen-fixing trees is significantly higher than other species,But no significant difference between needle and broad leaved tree species.On the whole present the trend of nitrogen-fixing trees>Hardwood species>conifer.Other properties,such as pH,there exist significant differences in soil nutrient content,But did not show obvious regularity,On the basis of different tree species and different.Significant differences plant characteristics of different tree species(leaf,litter and fine rootnutrient).Leaf features mainly N content and C/N index,the range of N content is 11.1?25.7 Between different types of tree species have obvious trend:Nitrogen-fixing trees was significantly higher than that of coniferous and broad leaved tree species,broad leaved tree species than conifer.Leaf C/N show the opposite trend.Litter features mainly for carbon,nitrogen,C/N and lignin/N significant difference exists among the indexes,and present a consistent with and leaf characteristic trend:Nitrogen-fixing trees>broad leaved tree species>conifer tree species.Fine root characteristics mainly for carbon and nitrogen content and carbon and nitrogen than fine root exist significant differences.