Effects of the conversion of subalpine spruce natural forest to plantation on soil bacterial communities and function in western Sichuan,China
The conversion of natural forests to plantations in the subalpine region of western Sichuan in China has resulted in the degradation of soil ecological function.Bacterial communities play an important role in regulating the maintenance and improvement of soil ecological functions.However,studies on the effects of conversion from natural forests to plantations on soil bacterial communities and functional groups are still lacking.Therefore,this study used a combination of high-throughput sequencing and Faprotax function prediction to determine the structure,diversity,and functional groups of soil bacterial communities in natural and planted subalpine spruces in western Sichuan.The effects of forest conversion were analyzed and the key factors driving these changes were clarified.The Shannon index of the bacterial community in spruce natural forest soil was significantly higher than that in spruce plantation soil whereas the Simpson's index was significantly lower than that of the spruce plantation soil.The principal co-ordinates analysis(PCoA)showed significant differences in the soil bacterial community composition between natural forests and plantations.The two forests shared 81.61％of the operational taxonomic units(OTUs),and the composition of bacterial communities with a relative abundance greater than 1％at the genus level was consistent,with a total of 23 genera.Bradyrhizobium,Vicinamibacteria,and KD4-96 were the dominant genera with significant differences between the two forest types.Functional prediction analysis revealed that the relative abundances of the dominant bacterial functional groups involved in chemoheterotrophy,aerobic chemoheterotrophy,and nitrogen fixation in the plantations were significantly higher than those in the natural forest.Redundancy analysis showed that soil pH,water content,total nitrogen,ammonium nitrogen,and microbial biomass nitrogen led to changes in soil bacterial community composition and functional groups.In conclusion,the conversion of subalpine spruce from natural to plantation forests in western Sichuan significantly affected the diversity and composition of soil bacterial communities and promoted an increase in the relative abundance of bacterial functional groups related to the carbon and nitrogen cycles.Our results provide a scientific basis for further understanding the effects of forest conversion on the ecological functions of soil.
western Sichuan subalpineforest conversionsoil bacterial community structurebacterial functional group
万方数据
维普
