Leymus Chinesis Grassland Improvements(Review)

Mechanisms of degraded Leymus chinensis grasslands and commonly used agronomic,chemical and biological measures were reviewed in this paper.The advantages and disadvantages of each improving method such as plowing,loosing,burning,over-sowing,fertilization and the applications of subtilis,corn stalks or gypsum were further clarified.Physical and chemical soil properties were significantly improved;Leymus chinensis roots were fully developed and occupied a larger ecological niche,and the competitive ability was further strengthened in improving grassland.Recovery speed of aboveground vegetation was apparently accelerated.Aboveground and underground materials had a positive coupling effect.Finally,three comprehensive improving models according to the different degraded levels of Leymus chinensis grassland were proposed in this paper.