The karst area in Yunnan-Guangxi-Guizhou region in southwest China is one of the largest contiguous karst areas in the world. Due to prolonged human activities, it has experienced severe rocky desertification.

Several studies report a greening trend in this karst area since the year 2000. While the start of the greening trend seems to match with the implementation of ecological conservation projects, statistical evidence on a relationship between vegetation greening and eco-engineering still needs to be determined.

Prof. WANG Kelin's research group from the Institute of Subtropical Agriculture (ISA) of the Chinese Academy of Sciences (CAS) studied vegetation trends in different geological settings to identify the dominant factors impacting vegetation trends in different project regions of southwest China and to distinguish factors that could enhance the impact of eco-engineering on vegetation trends.

The study was published in Science of the Total Environment on Jan.14. It was based on the time series GIMMS-3g NDVI datasets and six comprehensive factors representing the natural conditions and human activities.

"We find that eco-engineering is the main cause for vegetation increase in karst areas, while climate conditions and a decrease in rainfall are responsible for low vegetation growth in non-karst areas," said Prof. WANG.

Moreover, the researchers showed that the interaction of eco-engineering with other factors leads to a heterogeneous pattern of different vegetation trends.

Knowing and understanding the synergic influence of eco-engineering and natural factors on vegetation trends provide strategies for improving the efficiency of ecological restoration when planning and evaluating eco-engineering measures.

Contact: Wang Kelin

E-mail: kelin@isa.ac.cn

Institute of Subtropical Agriculture, Chinese Academy of Sciences