Effects Of Vegetation Type Of Maolan On Soil Enzyme And Microbial Community

Guizhou Maolan National Nature Reserve is the core area of the karst world natural heritage in southern China.It has rich biodiversity,and the karst virgin forests contained in it is characterized by strong nativeness and concentrated distribution,which plays a very important role in the research of karst forest.Moreover,the minority population in Maolan area is large,and the ethnic culture is rich and profound,which is an ideal area for carrying out ethnic ecology research.In this paper,four different vegetation type of primary forest,secondary forest,shrub forest,and herb in Maolan karst in Guizhou are taken as research objects.From the aspects of soil enzyme activity,bacteria,fungi,niche and soil layer,clarify the influence of different vegetation type on soil enzyme activity and microbial community.Aiming to better understand the relationship between soil enzyme activities,microbial communities,and vegetation type in karst forests,and to investigate the relationship between the traditional ecological wisdom of the local people and the environmental protection of Maolan in combination with relevant surveys of ethnic villages in the area.The main results are as follows:(1)With the scientific management,policies and regulations,and the joint participation of local residents,the Maolan Karst forest and ecological environment have been better protected and managed.The traditional ecological wisdom of all ethnic groups has gradually adapted them to the living environment of the region and integrated with nature.They have developed the habit of protecting the natural environment in all aspects of life and realized the protection of Maolan Karst environment from the source.On the other hand,local governments have reduced the intervention of human activities in karst forests through scientific development,protection and management of the ecological environment in the protected areas,and measures such as ecological relocation of residents,publicity and guidance,and restrictions on the area of construction land have effectively maintained and protected the environment of Maolan Karst ecological environment.At the same time,since the establishment of Maolan Nature Reserve,the vegetation coverage in the area has been increasing,and the area of forests and shrubs has increased significantly.(2)In the study of the effects of different vegetation type on soil enzyme activity,the five soil enzyme activities in each type showed L-Leucine amino peptidase(LAP)>?-1,4-glucoside(BG)>?-1,4-N-acetylglucosaminidase(NAG)>?-1,4-xyl-osidase(BX)>Cellobiohydrolase(CBH);In the vegetation type showed Shrub stage>Secondary forest stage>Primary forest stage>Herbal stage;LAP,BG,BX,and CBH have the highest activity in stone crevice in different habitats in each vegetation type,while NAG has the highest activity in different niches in different type;In soil profile,soil enzyme activity decreases with increasing soil depth.The soil enzyme activity in Maolan karst area is compounded by a variety of factors,which are affected by different vegetation type,soil physical and chemical factors,niche and soil depth.(3)In the study of soil microbial community characteristics,the dominant phylums and dominant genus of bacteria and fungi are not significantly different in different type,niche and soil layers.The dominant bacteria phylum are Proteobacteria,Actinobacteria,Acidobacteria,Chloroflexi and Nitrospirae.The dominant bacteria genus are norank?C?Acidobacteria,Nitrospira,and H16.The dominant fungi phylum are Ascomycota,Mortierellomycota,Basidiomycota,and unclassified?k?Fungi.The dominant genus is Mortierella,unclassified?p?Ascomycota,and unclassified?k?Fungi.The soil bacterial and fungal community structure and population are affected by different vegetation type,which are similar and different in the four vegetation types.Bacterial phylum and bacterial genera are the most unique species in the Herbal stage,fungal phylum unique species are only one species in the Shrub stage,and unique species of the fungal genera are most common in the Secondary forest stage.The number of bacterial differential species is shown as Herbal stage>Secondary forest stage>Primary forest stage>Shrub stage,while the number of fungal differential species is represented as Secondary forest stage>Primary forest stage>Shrub stage>Herbal stage.Influence of aboveground soil vegetation type and other environmental factors,soil fungi and bacteria show different abundances in niches and soil layers at each vegetation type.(4)Bacterial and fungal community richness and diversity are different in the four vegetation types soil.Bacterial community richness and diversity are higher in the Shrub stage than in the Secondary forest and Herbal stages.The fungal community richness and diversity are highest in the Secondary forest stage.The biological community richness of bacteria and fungi was the largest in stone crevices of Primary forest and Herbal stage,the bacteria was the largest in stone crevices of Secondary forest stage and stone gull of Shrub stage,and the fungi was the largest in soil surface of Secondary forest and Shrub stage.The bacterial community richness is higher in the soil surface layer than subsoil,the fungi appears as the soil surface layer>the lower layer in the Primary forest and Secondary forest stage,and as the soil surface layer<the soil lower layer in the Shrub stage and Herb stage.(5)Soil p H,TP,TN,SOC,and Available P have significant effects on soil bacterial genera in the Primary forest stage,Shrub stage and Herbal stage.The effects of NH₄⁺-N,NO₃⁺-N and C/N are relatively low.In the Secondary forest stage,the effect of p H was the lowest,and the effect of C/N was the highest.In the four types,N,P and SOC had a greater impact on each type fungal community,while p H and C/N have a lower impact.LAP,CBH,BX and BG have significant effects on the bacterial community in the Primary,Secondary and Herbal stages.NAG,LAP,BX and BG have a significantly higher effect on the bacterial community in the Shrub stage than CBH.Five soil enzymes had no obvious effect on the fungal community in four vegetation types,and BX had the least effect on the fungal community.In summary,soil enzymes,soil microorganisms,and soil physical and chemical factors are closely related.Soil enzyme activities and soil microorganisms in the soil of Maolan Karst area are affected by many factors.Soil enzyme activity and soil microorganisms are less affected than niche and soil depth in different vegetation type;Soil fungi are more sensitive than bacteria and are more susceptible to external factors such as ground vegetation type,rainfall and soil environment.In conclusion,this study can provide a scientific basis for Maolan to maintain the health and stability of the karst forest ecosystem and the construction and management of nature reserves.