Vegetation Restoration Of Degraded Grassland And Its Response To Grazing In Horqin

The Horqin Prairie is one of the animal husbandry bases in Inner Mongolia Autonomous Region,which has been seriously damaged by the long-term cultivation of cultivated fields and overgrazing,and the degradation of grasslands is increasing and spreading,which seriously affects the development of animal husbandry in Horqin region.In order to restore the damaged vegetation quickly in a short period of time,the vegetation restoration of the degraded grasslands of Horqin is carried out by artificial intervention,which provides the theoretical basis for the development of low-cost and high-efficiency animal husbandry.The experiment was conducted in the sandy land formed by degraded grassland in the Ar Horqin Banner of Chifeng City from 2018 to 2019,using Prairie No.3 and wheatgrass carried out four methods of mixed sowing and two kinds of unicast reconstruction of artificial grassland.The variance analysis was used to compare the height,coverage,density,biomass,interspecific competition;Vegetation restoration of degraded grassland in 2017 using Leymus chinensis,Bromus inermis,Elymus dahuricus,Prairie 3 and Astragalus adsurgens.Analysis of the effects of grazing on the communities characteristics of artificial grassland,soil physical and chemical properties and nutrients.The following main results:(1)The second year of dry grassland planting,the coverage and density of mixed-mixing treatment 1 rows of alfalfa+1 rows of wheatgrass and 2 rows of alfalfa+1 rows of wheatgrass are superior to unicast treatment.Relative total yield of treatment 1 row of alfalfa+1 row of wheatgrass was greater than 1,indicating that there was a certain degree of coexistence relationship,which was beneficial to community stability.(2)Under irrigation conditions,compared with the original vegetation,the mixed grassland had different degrees of increase in community height,coverage and grass population density;height and existing population of vegetation communities in the grazing area were significantly lower than those in the non-grazing area,and the community Richness,biodiversity and uniformity are higher than no-grazing areas.(3)Compared with the no-grazing areas,the soil moisture content and pH value of the grazing area decreased,soil bulk density,organic matter content nitrogen content and surface soil available potassium increased,and the total phosphorus total potassium content did not differ much.With the increase of soil depth,the content of available potassium and total phosphorus total potassium decreased.The C/N and C/P values of the grazing area were higher than those of the no-grazing area.Soil total C and C/N were significantly positively correlated(p<0.01),soil total C and C/P were significantly positively correlated(p<0.05),and soil P was significantly negatively correlated with C/P and N/P(p<0.05).