In order to study the community features

soil nutrient characteristics and their correlations in different degraded grasslands of East Qilian Mountains

the lightly degraded grassland (LDG)

moderately degraded grassland (MDG) and heavily degraded grassland (SDG) were taken as the research objects

and the combination of field investigation

laboratory measurement and data statistical analysis was adopted. The results showed that:(1) The characteristics of plant communities

including aboveground biomass

height

density

frequency and vegetation coverage

showed a decreasing trend from LDG to SDG

and the difference was significant (P < 0.05). And the species Margalef index

Shannon index and Evenness index of the MDG were the maximum

however

the Dominance index was the minimum. (2) There were 19 families

38 genera and 41 species in the study area

and the plants with strong ecological adaptability mainly concentrated in Legumes

Gramineae

Compositae and Rosaceae. The vegetation types of different degraded grasslands included K. humilis with Leymus secalinus

K. humilis with Thalictrum alpinum

K. humilis with L. secalinus

among which K. humilis was the dominant species in different degraded grasslands. In different degraded grasslands

the functional groups were dominated by forbs

followed by Gramineae grasses and poison grasses. (3) With the aggravation of grassland degradation

soil available nitrogen

available phosphorus

organic carbon and water content all decreased

while pH increased. (4) The highest contribution rate of soil factors to vegetation growth in different degraded grasslands was the available nitrogen

available phosphorus and water content

respectively. In summary

with the aggravation of grassland degradation

the community structure of plants was changing to a single trend

soil nutrient content was reduced and the contribution rate of soil factors to plants was also changed accordingly.