| A Study was made on the relationship between species diversity in different restoration stages of Hippophae rhamnoides ssp.sinensis plantations and soil fertility in the hilly and gully region of Loess Plateau.The results showed that the index of α-diversities and the content of organic matter and nitrogen were obviously in positive correlation in the early stage and middle period stage of Hippophae rhamnoides ssp.sinensis plantations restoration,the greater change of the index of β-diversities occurred in the middle period stages of Hippophae rhamnoides ssp.sinensis plantations restoration,and the content of organic matter changed comparatively large,while Hippophae rhamnoides ssp.sinensis plantations restored,the content of organic matter increased,their changes were basically in the same step.An analysis of multivariate regression on relationship of soil fertility and plant composition characteristic,the results showed that the content of the nitrogen was related to the number of woody plants,plants and species diversity,the content of the phosphate was related to plant species diversity.The changes of the content of potassium and pH of soil was comparatively complicated,and wasn't obviously related to plant composition characteristics. |