Resource Allocation Strategies Of Eight Grassland Species As Influenced By Nitrogen Rate

Nitrogen is one of the most important elements that are vital to plant growth. Also, it is one of the main limiting factor to plant individual.even net ecosystem primary productivity. The productivity of the grassland ecosystem is decided by the supply of the soil nitrogen .But the degeneration of the ecosystem takes a great deal of soil nutrient away, which will worsen the loss of the soil nutrient, making the fatty soil descend, then causing the level of grassland ecosystem productivity lower furtherly.Thus, the study and knowledge about the mechanism of adaptation and use of nutrition under different concentration of nitrogen is important for grassland plants growth, they are the basis of exertion of grassland plants' potential capacity, improvement of grassland ecosystem productivity, and silviculture and management of grassland.We studied the Biomass, Root shoot ratio,Nitrogen concentration, Nitrogen content, Nitrogen allocation and Nitrogen use efficiency of 8 species belong to 4 life forms in different nitrogen levels.And the results suggested:The traits of the same species in different nitrogen levels The Biomass of Artemisia. Intramongolica, Stipa grandis , Chenopodium glaucum , Cleistogenes squarrosa showed significantly arised with the nitrogen appended. At the same time the Root shoot ratio of Artemisia. Intramongolica and Bromus. Innermis arised, and the Nitrogen concentration of Artemisia, frigida, A. Intramongolica, Bromus. Innermis and Stipa grandis ascended altogether. The N content of subshrubs, rhizomous grasses and bunchgrasses and one annual species(Chenopodium glaucum) went up significantly along with the nitrogen arised, and the NUE of Artemisia, frigida , Bromus. Innermis, Chenopodium glaucum, descended notably.Biomass and its'allocation of 8 species belong to different life forms: Biomass of 8 species at early stage (July 25^th) and late stage(September 3rd): Salsola collina > Chenopodium glaucum > Artemisia, intramongolica > Artemisia frigida > Bromus. Innermis , Agropyron michnoi,...