Distributed Mechanisms And Assemblies Of Soil Microbes Among Main Vegetation Restoration Types In The Southern Taihang Mountain

The southern Taihang Mountain area has a typical arid and semi-arid climate.The lack of rainfall,soil degradation,and poor geological conditions are causing extreme difficulties for ecological restoration.Plantation engineering,shrub-herb combinations,and other vegetation restoration projects are key to improving the ecological environment.Based on the conditions of the Xiaolangdi Forest Eco-Station of the State Forestry Administration,the main vegetation restoration types in the southern Taihang Mountain were studied.We explored the differences in soil conduction and changes in soil microbial communities among different habitat types to confirm the effects of vegetation restoration on soil microbial communities and the soil ecosystem.The results will provide some important theoretical reference and practical significance for ecological reconstruction in semi-arid areas in the future.By the studies of the main vegetation restoration types in the southern Taihang Mountain.The results show that forest vegetation restoration type had more of an effect on soil conditions than those of grasses and shrubs.The highest soil organic matter content was detected in the Platycladus orientalis of each soil layer;the available phosphorus content of Quercus variabilis in the soil layers was significantly higher than that of the other restoration types(p < 0.05).The soil nutrients in the underground forest land were correlated with the root system index,in which available nitrogen was significantly correlated with the root dry-wet ratio and root specific surface area(p <0.05).Available phosphorus was significantly correlated with root specific surface area(p< 0.01).Our results confirm that soil conduction and the fine root index in a semi-arid area can been improved by a series of vegetation restoration measures,but vegetation restoration does not significantly affect soil particle size(p > 0.05).We also found that the Vitex negundo and Ziziphus jujube,P.orientalis and mixed grassland,Q.variabilis and Robinia pseudoacacia had similar effects on soil condition and root structure.The results will been used as a guide for local afforestation in the future.In this study,the differences in soil AMF communities among four habitat types(forest,shrub,grassland,and arable land)in the southern Taihang Mountain were analyzed though high-throughput sequencing(Illumina platform).The results show thatthe species diversity and composition of soil AMF communities were different among each habitat type;the Glomus community was the dominant species.Based on a redundancy analysis,the results show that water content,available phosphorus and available potassium were the main environmental factors significantly affecting the AMF community(p < 0.05),and soil texture was an important factor driving the distribution of the AMF community.The diversity of AMF in the forest habitat was much lower than that of the other habitat types.Our study may provide some new clues into the characteristics of AMF composition and distribution in semi-arid areas.Based on the four different habitat types that have been established,the composition and distribution of soil eukaryotic microbial communities has been analyzed in the southern Taihang Mountain.The results show that the composition of soil eukaryotic microbial communities differed among the different habitats,and the highest value of richness and diversity of the soil eukaryotic microbial communities was in the forest.SAR and Metazoan communities dominated the soil eukaryotic microbes.The soil eukaryotic microbial communities coexisted among the four vegetation restoration types makes up approximately 26%.Based on a redundancy analysis,this study also revealed the relationship between the soil eukaryotic microbial communities and environmental factors.The results confirmed that soil O-layer elements,soil water content,organic matter,and altitude were the important driving factors of the soil eukaryotic microbial communities,and had a significant impact on these communities(P < 0.05).These findings confirm that the afforestation may prove to be an effective method for restoring local vegetation.The experimental data also enhance information on soil eukaryotic microbial communities in semi-arid areas.In this study,we investigated the bare patches with typical semi-arid characteristics in the Taihang Mountain.Our results show that the soil chemical properties at the vegetation coverage sampling sites were better than those without vegetation.The properties of the small trees were better than the grassland or the bare patch.The results also indicate that the diversity and richness of the soil fungal community improved significantly in response to vegetation coverage(p < 0.05),confirming that vegetation coverage could play a positive role in soil remediation and microbial diffusion.At the same time,our study confirmed that Ascomycota and Basidiomycota communities were the dominant fungal phyla in bare patches.A redundancy analysis showed that environmental factors were the main factors affecting distribution of the soil fungal community,and that moisture content,soil organic matter,total nitrogen,and organic carbon were the most important environmental factors(P < 0.05).Our study explored the importance of vegetation cover for rehabilitating the bare patches in a semi-arid area.The soil bacterial communities in bare patches were analyzed in the Taihang Mountain.The results show that the bacterial microbial communities at the sampling sitesincreased in response to the vegetation coverage project.The results also show that soil bacterial diversity and richness among the vegetation coverage types were significantly higher than those of bare patches(P < 0.05).Our study confirmed that vegetation restoration improved survival and reproduction of the bacterial communities in bare patches.Proteobacteria,Acidobacteria,and Actinonobacteria were the dominant bacterial communities.A redundancy analysis showed that water content,organic matter,and organic carbon were the main environmental factors significantly affecting the distribution of soil bacterial communities(P < 0.05).The index of fungal diversity and richness in bare patches was lower than that of the bacterial communities.In addition,a Venn diagram analysis showed that there were 61.7% shared operational taxonomic units(OTUs)in the bacterial communities but only 11.5% shared OTUs were detected in the fungal communities,indicating that the bacterial communities were widely distributed among different vegetation coverage types and they had a greater ability to distribute than the fungal communities.In summary,the characteristics and diversity of soil microbial communities were fully analyzed in the southern Taihang Mountain from the perspective of vegetation restoration.Our studies confirmed that semi-arid soil conditions could be effectively improved by vegetation restoration measures.Variations in the vegetation restoration types affected the richness and diversity of the soil microbial communities.Soil nutrients and texture were the important driving factors for distribution of the soil microbial communities.Vegetation restoration promoted reproduction of soil microorganisms and increased soil nutrients in bare patches of the semi-arid mountainous area.These results will provide a valuable reference for water and soil conservation,controlling the bare patches or other ecological restoration projects in the Taihang Mountain and other semi-arid areas.