| The“black-soil”mountain in the source area of the three rivers is facing serious grassland degradation and soil erosion problems.The cultivation test of forage varieties on the shade and sunny slopes were carried out in Dari County from 2019in order to solve the problems of vegetation restoration of the“black-soil”mountain.14 species all belong to the gramineous forages.Some of them are being cultivated and domesticated species,and others have been popularized on the Qinghai-Tibet Plateau as the research object.In the context,the indexes of different forage grasses such as the seeding emergence rate,growth period,plant height,fresh grass yield,seed yield,thousand-grain weight were observed and measured.Furthermore,the good forage species being suitable for black soil mountain planting were screened out through the adaptability evaluation of forage.Our research would provide a theoretical basis for vegetation restoration and ecological protection.The results are as follows:(1)The 14 forage species tested on the sunny and shade slopes can survive the winter normally.Among of them,13 species on the sunny slope can complete the growth period in the following year.Then all of them began to return green in the middle or late ten days of April in the following year.Similarly,there are 12 species on the shade slope can complete their growth periods.They began to return green from mid-to-late days of April to early days of May in the following year.(2)The highest fresh weight of Elymus tangutorum on the sunny slope was up to 590.00g/m~2 and 3,593.33g/m~2 in the year of planting and the second year of planting;The highest weight,as high as 580.00g/m~2,the lowest fresh weight of northwest fescue,only 94.00g/m~2,the highest fresh weight of Elymus tangutorum in the second year of planting,as high as 3326.67g/m~2,and the lowest fresh weight of Stipa thinner.Only 60.00g/m~2;in the second year of planting,the dry weight of Elymus breviaristatus cv.Tongde is 908.88g/m~2,and the minimum dry weight of Stipa sparser is 48.00 g/m~2;planting In the second year,the dry weight of the shady slope was 912.68g/m~2 with the highest dry weight of Maibin grass,and the lowest dry weight was 46.00g/m~2 with Stipa sparser.(3)Elymus submuticus cv.Tongde(Elymus submuticus cv.Tongde)has the highest total underground biomass on sunny slopes,up to 6359.03g/m~2,and the lowest is Poa crymophila.cv.Qinghai.It is only 1597.99g/m~2;the highest underground biomass in the shady slope is Elymus nutans(5171.80g/m~2),and the lowest is Qinghai coldland bluegrass(1883.72g/m~2).(4)The comprehensive analysis and evaluation results of morphological characteristics show that the grass species with better growth on the sunny slopes include Elymus sibiricus L.cv.Tongde,Elymus breviaristatus cv.Tongde,Elymus submuticus.cv.Tongde,Elymus nutans,Elymus tangutorum,Poa crymophila cv.Qinghai and Poa pratensis cv.Qinghai;the grass species that grow better on shade slopes are Poa pratensis cv.Qinghai,Puccinellia tenuiflora.cv.Tongde,Elymus nutans,Elymus submuticus.cv.Tongde,Elymus sibiricus cv.Tongde,Koeleria cristata,Elymus tangutorum and Elymus breviaristatus cv.Tongde. |
