Response Of Dominant Population And Trait Of Stipa Breviflora In Desert Steppe To Grazing Intensity

One of the majorest ways of using desert grassland is grazing.With Sonid Right Banner Stipa breviflora desert steep as the object,Study the influence of the main advantage plant in different grazing intensities,The research object was Stipa breviflora to investigate the reproductive traits,root traits,biomass allocation and seed germination under different grazing intensities,The result as follows:1.Moderate grazing can significantly increase the population height of Stipa breviflora,Dominant population height gradually declines with the stocking rate increases.Hight grazing can reduces population density of Stipa breviflora,increase population density of Convolvulus ammannii within unit area.Hight grazing will significantly reduce Standing crop dynamics.The hight important value of dominant population is Stipa breviflora,important value with the increase of stocking rate to reduce.The important value of Allium polyrrhizum and Convolvulus ammannii in Height grazing to increased.2.The plant number of basal diameter?under the grazing treatment is the highest,With the increase of grazing intensity decrease first and then rise,No grazing treatment the main breeding way is vegetative propagation.With the stocking rate increase the number of vegetative shoots and vegetative shoots were significantly reduced.Moderate grazing reproductive have high seed number of Stipa breviflora.3.Moderate grazing can promote the growth of root length,root number,root biomass and root-shoot ratio of Stipa breviflora,with the increase of grazing intensity there is an inverted"V"trend.Moderate grazing can significantly increase leaf weight and leaf fraction,No grazing and Moderate grazing root shoot ratio and underground Part Fraction were significantly higher than heavy grazing.4.The Stipa breviflora seed length,width,weight,and awn weights of grazing were significantly lower than no grazing treatments.It is more use wind move away from the plant body spread to suitable habitats.There are two peak germinations in the germination period of Stipa breviflora,The first time in 3d⁷d,second time in 9d¹1d.The cumulative germination rate of grazing seeds is greater than 85%,the no grazing cumulative germination rate is only 22%.The regulation of moderate grazing(1.92sheep·hm²·a^-1)was more reasonable in Stipa breviflora desert steppe,Promote the sustainable development of grassland and grassland utilization.