*Evaluation of Soil Seed Banks in Different Aged* Caragana microphylla*… DOI: http://dx.doi.org/10.5772/intechopen.98712*

**Table2.**

 *Average species compositions and seed densities in the SSB of different aged* C. microphylla *plantation and control.*

*C. microphylla* plantation, the overall richness of species in the SSB increased dramatically, then decreased slightly (**Figure 2**). Within 0–2 cm soils along the age gradient of semi-fixed dunes to older *C. microphylla* plantation, the species richness was 10, 18, 21, 20 and 20, respectively. Species richness trended similarly along the age gradients for soils within the 2–5 cm, 5–10 cm, and 0–10 cm. The level of species richness was higher in the *C. microphylla* plantation compared to the natural steppe for all soil depths, with the exception of those of the 25 years *C. microphylla* plantation. The number of species in the 2–10 cm soil layer was 3, 3, 4, 0, 3, and 4, respectively.
