Study On The Effects Of Different Grazing Intensities On The Vegetation And Soil Of Caragana Shrub Forest

The construction of Caragana shrubland has played an important role in wind prevention and sand fixation,soil and water conservation,and other aspects in the western desert grassland area of Inner Mongolia.However,due to improper protection and utilization measures,a large area of decline has been caused.Therefore,the scientific and rational use of Caragana shrubland is an important scientific problem that we urgently need to solve.Grazing is an important means of grassland management.Caragana shrub forests have dual attributes of grassland and forest land.Can livestock grazing be used for shrub forest regeneration and rejuvenation? Can livestock grazing balance the ecological and production value of the Caragana shrub forest,and achieve a win-win situation? Based on the above issues,this study selected representative artificial shrub forests of Caragana korshinskii with a planting period of up to 17 years in the desert grassland area of Inner Mongolia as the research object.Through a combination of indoor experiments and field investigations,different grazing intensity experimental areas were established to study fence grazing prohibition(CK),light grazing(LG),moderate grazing(MG)The effects of different grazing intensities such as heavy grazing(HG)on the vegetation community and soil physicochemical properties of Caragana korshinskii forest.This thesis mainly analyzes the effects of different grazing intensities on the species composition,quantitative characteristics,diversity of vegetation,soil texture,soil bulk density,water content,and nutrients,and discusses the correlation between vegetation and soil.It preliminarily determines the appropriate grazing intensity of Caragana korshinskii shrubbery in the desert steppe area of Inner Mongolia,providing a scientific basis for the rational and sustainable use of Caragana korshinskii shrubbery in the desert steppe area,Provide new ideas for the scientific and rational utilization of Caragana shrub forests.The results indicate that:1.Grazing significantly changed the species composition and its important value,plant community structure and diversity of Caragana korshinskii shrubbery community.With the increase of grazing intensity,the community height,coverage,and biomass significantly decrease,while the community density shows the opposite trend.Under heavy grazing,the community density is the highest,and the diversity index is the highest in light grazing.This indicates that light grazing can change the competitive pattern of grassland communities and increase community richness.The feeding of caragana also increases with the increase of grazing intensity,with different grazing intensities showing a trend of severe>moderate>mild.With the increase of grazing intensity,the number of regenerated branches and regeneration height also show a decreasing trend,and there is a significant difference between different grazing intensities(P<0.05).Light grazing is helpful for the regeneration of caragana.2.With the increase of grazing intensity,the content of soil clay and silt particles generally shows a decreasing trend,while the content of sand particles shows an increasing trend.Light grazing is beneficial for increasing soil moisture content and reducing bulk density.Grazing has a significant impact on the organic carbon and total nitrogen content in the 0-10 cm soil layer.With the increase of grazing intensity,the content of soil organic carbon and total nitrogen in each soil layer increased first and then decreased.It is beneficial to the improvement of soil structure and soil water storage to reach the highest grazing intensity in light or medium grazing intensity.With the increase of grazing intensity,the content of total phosphorus and available phosphorus in the soil shows a decreasing trend.The available potassium content in the 0-30 cm soil is mild>control>severe>moderate.3.With the increase of grazing intensity,the contents of cellulose,hemicellulose and lignin in Caragana korshinskii reach the minimum value in light grazing.Light grazing helps to reduce the contents of cellulose,hemicellulose and lignin in Caragana korshinskii,while high-intensity grazing is on the contrary.The contents of crude protein and crude fat increase in light grazing,and light grazing significantly increases the weight of livestock.4.Based on the above experimental results,light grazing can stimulate the growth of forage,improve soil physicochemical properties,increase protein content of caragana,and increase livestock production.Therefore,combining theory and practice,it is determined that light grazing(LG)is the appropriate grazing intensity for caragana shrub forests.