3.1 Vegetation characteristics
Species diversity is an important feature of ecosystem stability
maintenance and function operation, and vegetation productivity is an
important indicator to characterize the plant ecological function
stability and regional ecological carrying capacity (Pennekamp et al.,
2018; Campos-Herrera, et al., 2013). Tang et al. (2016) found that, with
the succession of grassland to desert, species richness, total
vegetation coverage, dominant abundance, richness index and aboveground
organisms all showed a downward trend. In this study, compared with TS,
the coverage, AGB, Shannon-Weiner index and richness decreased, which
was similar to the results of the Meng et al. (2018) study. Due to the
suitable water and heat conditions in the temperate steppe distribution
area, it was mainly composed of perennial herbs. The Temperate Steppe
Desert was used for water limitation, and part of the herbaceous plants
were degraded and formed mainly herbaceous and semi-shrub vegetation.
However, due to extremely rare rainfall, dwarf shrubs and subshrubs with
strong drought resistance were mainly found in temperate desert (Zhang
et al., 2015). Evolving from temperate steppe to temperate desert, the
vegetation structure gradually becomes uniform and the stability of the
ecosystem decreases (Sharma et al., 2009).