Community Composition and Soil Properties of Different Grassland Types on the Tala Shoal in Gonghe Basin
There exist three most representative plant communities within the Tala Shoal in Gonghe Basin,including Stipa breviflora and Orinus kokonorica grassland,Achnatherum splendens grassland,and Caragana tibetica shrubland.Field data of plant and soil investigation from 19 samples plots in 95 quadrats (1 m × 1 m) was used to explore the community composition,soil texture and nutrient status of the three communities.Up to 32 plant species in total were found in the sample plot,with 11,22 and 21 plant species in C.tibetica shrubland,A.splendens and S.breviflora grasslands respectively.The plant biomass and coverage was higher in the A.splendens grassland than in the O.kokonorica grassland,and the C.tibetica shrubland had the lowest plant biomass and coverage among the three communities,with O.kokonorica the dominant plants.The soil content to 20 cm in different particle-size separates was dominated by the fine sand.The soil nutrient concentrations of P,K,and N were higher in the C.tibetica than in the other two communities as the result of accumulation phenomenon,while the soil EC in the A.splendens grassland was 0.26 ms · cm-1 with poor nutrient and weak salinization.Plant communities and their soil adaptation may offer guideline for the rehabilitation of degradation grassland.