Effect Of Mowing, Fertliization On Aboveground Biomass Of Leymus Chinensis Community In Xilingol Typical Steppe

Leymus chinensis grassland is not only the main vegetation type of typical steppe in Xilingol,but also the main mowing grassland,which plays an important role in the production and development of animal husbandry.Grassland management and the maintenance of vegetation productivity are the key problems to be solved in this area.In this study,the Latin square-split zone design was used to analyze the effects of mowing,fertilization and year(precipitation,temperature and years)on the aboveground biomass,species composition and structure of Leymus chinensis,so as to provide scientific guidance for the practice of vegetation restoration.The results are as follows:1.Mowing and fertilization increased the aboveground biomass of the plant community,and the independent effect of fertilization was significant.2.Mowing and fertilization increased the aboveground biomass of Leymus chinensis population,continuous fertilization could increase the aboveground biomass of Stipa krylovii Roshev population,mowing and continuous fertilization could increase the aboveground biomass of Stipa krylovii Roshev and Cleistogenes squarrosa populations.Fertilization and year had significant independent effect on Stipa krylovii Roshev population,and year had significant independent effect on Leymus chinensis and Cleistogenes squarrosa population.3.Mowing and fertilization can improve the species richness and the intensity of interspecific competition,and the independent effect of the year is significant.4.Mowing increased the relative aboveground biomass of forbs and annuals and biennials.Apply fertilizer once increased the relative aboveground biomass of shrubs and semi-shrubs and forbs.and continuous fertilization increased the relative aboveground biomass of tall bunchgrasses,forbs and annuals and biennials.Mowing and fertilizer once increased the relative aboveground biomass of shrub semi-shrubs,forbs and annuals and biennials.Mowing and continuous fertilization increased the relative aboveground biomass of shrubs,semi-shrubs,tall bunchgrasses and annuals and biennials.Mowing,fertilization,year and their interaction had significant effects on shrubs and semi-shrubs,mowing and year had significant independent effects on rhizome grass.Fertilization and year had significant independent effects on tall bunchgrasses,year had significant independent effects on dwarf bunchgrasses,fertilization had significant independent effects on forbs,and mowing,fertilization and year had significant independent effects on annuals and biennials.5.The annual dynamics of aboveground biomass of undisturbed plant communities depends on annual precipitation and precipitation from January to July,while that of other treatments depends on the changes of population,species richness and functional group composition caused by disturbance.During fertilizer once,mowing and continuous fertilization,the precipitation from January to July had an indirect effect on the aboveground biomass of the plant community through Leymus chinensis population and shrub and semi-shrub.