Abstract
The Loess Plateau in China is an important area for mineral resources and therefore heavily exploited. As a measure to solve the conflict between conservation and development, ecological restoration has attracted more and more attention. More methods are needed to assess their effectiveness in achieving ecological and social goals. To adequately assess the effectiveness of natural restoration, the naturalness index (NI) has been developed to evaluate restoration effectiveness based on the Soil nutrient index (SNI), community composition index (CCI), and community succession index (CSI). By developing and applying of the NI to an open-pit mining area on Loess plateau, northwest China, the results show that: (i) In the study area, the cumulative dominance index of perennial grasses, the community function index, soil organic matter, and soil hydrolysable nitrogen greatly explained the community development. (ii) All the indicators values have changed with the increase of revolution time, the value of SNI increase obviously than the CCI and CSI comparing with the control plot, which indicated that the soil nutrient could be completely restored more easily. (iii) According to the Logistic Growth Model between NI and restoration time, it can be deduced that an ecosystem similar to the original ecosystem could be established after about 29 years of natural restoration.
Highlights
While the community composition index (CCI) increased over a period of 10 years, the Community succession index (CSI) increased over 15 years
The so-called “dominant competition period”, the community was characterized by the decrease in species and the appearance of dominant species; this phase lasts longer than the “lottery competition period”
The results of our study suggest that with increasing restoration time, the naturalness index (NI) increases, which means that over time, the plant community more closely resembles the original one
Summary
The study area was located in eastern Jungar Banner, Erdos City, Inner Mongolia Autonomous Region, Northwest China (111 ̊13’- 111 ̊200 E, 39 ̊43’- 39 ̊490N) (Fig 1). The climate is warm temperate, semi-arid continental climate. Average annual temperature is 7.2 ̊C, with an average annual precipitation of 231–460 mm. The zonal vegetation of the hilly slopes is characterized as warm temperate steppe vegetation. Stipa bungeana grassland is the original vegetation type, but only occurs in the form of several small fragments. The remaining fragments are mainly composed of a Stipa bungeana + Cleistogenes squarrosa + forb community; the main species are Stipa bungeana, Cleistogenes squarrosa, Leymus chinensis, Thymus mongolicus, Lespedeza davurica, Medicago ruthenica, Astragalus scaberrimus, and Oxytropis chiliophylla. The landscape is monotonous, with a simple community composition
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
