*2.5.3 Coupling coordination analysis of vegetation and soil system of* H. ammodendron *plantation*

According to the data of **Table 7**, vegetation-soil coupling degree (C) of plantation was arranged on the order of 33 > 23 > 42 > 20 > 17 > 28 > 12 > 15 > 7. When *H. ammodendron* grew up to the age of 17, the interaction between vegetation and soil increased obviously and tended to be stable. The C of the 33-yr-old plantation was 73.85% increased than 7-yr-old one. The D of *H. ammodendron* plantations was arranged on the following order: 28 > 42 > 20 > 17 > 33 > 12 > 23 > 15 > 7. The D of 28-yr-old plantation was 96.63% increased than 7-yr-old one.

On the whole, the C and D of nine plantations showed a fluctuating and increasing trend along with the age increasing. *H. ammodendron* populations always kept at the level of disorder and declining, and vegetation and soil were in the state


*Characteristic on the Stability of* Haloxylon ammodendron *Plantation… DOI: http://dx.doi.org/10.5772/intechopen.99050*

> **Table 5.**

 *The basal characteristic of vegetation and soil in* H. ammodendron *plantations.*


#### **Table 6.**

*Types of vegetation and soil coupling coordinated development.*

of profit and loss. However, the degree of disorder on profit and loss showed the trend from serious to slight (**Table 7**).
