Study On The Characteristics Of Five Plant Communities And Soil In Bayan Wenduer Desert

In this study,five major communities of Haloxylon ammodendron,Nitraria tangutorum,Nitraria sphaerocarpa,Kalidium foliatum and Ephedra przewalskii and their undergrowth soils were studied in the desert steppe of the Baiywendur Desert.Field investigation and laboratory experiments were conducted.The vegetation and soil characteristics of different plant communities were analyzed.The in-depth study of the relationship between the characteristics of typical plant communities and soil physical and chemical characteristics in Bayan Wenduer Desert is beneficial to scientifically reveal the distribution law of plant communities in the desert steppe region,and provide certain theoretical guidance for the restoration and management of degraded grassland in the desert steppe region as well as the protection and development of desert plant communities.(1)Desert savanes 5 kinds of plant community has obvious dominant species and the ground vegetation are shrubs,The community diversity of Kalidium foliatum is the best,Ephedra przewalskii community evenness is best,Nitraria sphaerocarpacommunity richness supreme.The adaptability of Nitraria sphaerocarpa and Kalidium foliatum communities in desert steppe area is the best.The aboveground biomass of Haloxylon ammodendron community was the highest.(2)Soil physical properties of different plant communities were different in different communities and different soil layers.The soil in Ephedra przewalskii community was more compact,and the soil in Kalidium foliatum community was more loose.Kalidium foliatum communities had the best soil permeability and Ephedra przewalskii communities had the worst soil permeability.The soil moisture content of each community increased with the increase of soil depth,The non-capillary water holding capacity of soil is:The soil water holding capacity of Kalidium foliatum community was the best,and that of Ephedra przewalskii community was the worst.(3)Soil chemical properties of different plant communities were different in different communities and different soil layers.The soil nutrient content of Haloxylon ammodendron community was best and the Nitraria sphaerocarpa community was worst.In addition,the soil of Kalidium foliatum community is moderately saline-alkali soil and the salinization is more serious.The soil salt ions Na⁺and CO₃^2-have the strongest correlation with the total soil salinity,and are the main ions in soil salinity.(4)Soil physical and chemical indexes of different communities were closely related,and the correlations among physical and chemical indexes of different communities were different.The total soil porosity was positively correlated with capillary porosity and capillary water holding capacity in the five communities.Soil electrical conductivity was positively correlated with total salt content in all communities.There was a negative correlation between soil organic matter and total salinity in all communities.There was a significant positive correlation between soil total N and total P in all communities.(5)The physical and chemical correlation between aboveground vegetation and soil was low in different plant communities.The Shannon-Wiener diversity index and Simpson diversity index were positively correlated with non-capillary porosity in the five communities,and the non-capillary porosity was the main factor affecting plant diversity.The aboveground biomass of the community was positively correlated with soil total nitrogen,and soil total nitrogen content was the main factor affecting aboveground biomass of the community.There was no significant correlation between other factors.