Evaluation Of Production Performance And Adaptability Of Mixed-sown Grasslands Of Early Maturing Grass And Other Forage Grasses In The Qinghai-Tibet Plateau

Qinghai flat stem precocious maturing grain(Poa pratensis var.anceps Gaund.cv.Qinghai)has the characteristics of cold resistance,drought resistance,fast root reproduction,and strong stress resistance.Its large number of roots and roots can quickly form sod,which is an excellent grass species to control grassland degradation and protect the ecological environment.However,it limits own application in animal husbandry due to the low forage yield of precocious ripening grass.Therefore,how to protect ecological environment while improving the productivity of the grassland has become the key problem to realize the strategy of "one excellent and two high".As a planting mode with efficient utilization of resources,mixed broadcasting is a cuttingedge technology to promote the sustainable development of agriculture.Compared with unicast,mixed mode can improve the competition between species and make full use of resources.Therefore,this experiment uses old wheat(Elymus sibiricus),fescue(Festuca sinensis),alkali grass(Puccinellia tenuiflora)different grass in precocious grass(Poa pratensis),in order to use the characteristics of different grass,establish mixed grassland with strong grassland stability and high productivity,providing theoretical and practical basis for the hai-Tibet plateau region mixed grassland.In this experiment,as plant morphological characteristics,biomass accumulation and distribution,and nutrient characteristics of mixed sowing grassland were carried out in Xihai Town,Haibei Prefecture,and the following conclusions were drawn:(1)The use of different grass species and precocious grass can effectively improve the performance of mixed sowing grass with precocious grass as the main grass species.Middle old wheat and precocious grain mixed grass has the highest forage yield.The yield of mixed grass of old wheat and precocious-aged grain was higher than194.22%,458.36% and 194.22% of 2-aged grass,3-aged grassland and 4-aged grass,respectively.Therefore,in order to solve the problem of insufficient productivity of precocious grass,old wheat and precocious grass can be mixed sowing.(2)Using different grass and precocious grain mixed sowing,precocious grain can all be set in a suppressed state.Among them,the use of alkali grass and precocious maturity grain mixed sowing has a high interspecific compatibility.When alkaline grass and precocious grass were mixed,the relative GDP(RYT)was significantly greater than 1.0 in third-old grass and fourth-old grass.Moreover,with the increase of grass planting years,the relative total product of alkaline grass and precocious grass has high community stability and yield stability.Therefore,the selection of alkali grass and precocious maturing grain for mixed sowing can be used to build a mixed sowing grassland for the purpose of ecological management.