Application of Gray Relevant Analysis in Cultivation Mode Evaluation of Shrub-Grass Composite:A Case Study of Hot-Arid Valley of the Jinsha River in Yongsheng County,Yunnan The Characteristics and Utilization of Shrub-grasslands in Tropical and Subtropical Mountains of Yunnan Temporal and spatial variation in surface soil moisture content of karst slopes in the dry season Effect of Cutting on Grassland Species Diversity and Productivity of Shrub-grass in Hilly Areas A Study on the Productivity of Secondary Shrub Thicket and Shrub-Grassland in Yixian County,Anhui Province