Mechanisms on Vegetation Restoration of the Karst Ecosystem
The karst areas of the south-west China are vulnerable ecological regions, where rocky desertification is widely developed. To improve ecological environment and enhance agriculture condition, vegetation restoration has been taken since 1970s. The functions, resilience and stability of ecosystems are determined by interactions of vegetation, soil physical and chemical conditions and soil microbial communities.
Therefore, researchers ZHU Hanhua and other researchers in Institute of Subtropical Agriculture, Chinese Academy of Sciences (ISA) selected five typical vegetation successional sites at the experimental sites established in Huanjiang County, Guangxi Province. They carried out a series of experiments with the purpose of evaluating changes of soil physico-chemical and microbial properties throughout the vegetation succession and studying interactions of vegetation succession, soil bio-chemical properties and microbial phylogenetic diversity and catabolic capability in Karst ecosystems.
The experimental data reveals that vegetation succession in the Karst ecosystems significantly improved soil organic carbon(OC), N nutrient and physical conditions, which resulted in the increases of soil microbial biomass, bacterial an fungal phylogenetic diversity, and bacterial catabolic diversity, and hence the catabolic capability of soil bacterial communities on complex organic substrates. It is also found that the accumulation of soil OC along the vegetation succession was a core factor contributing to the improvements of N status and the physical and chemical conditions, and also to the regulation of the biomass and phylogenetic and catabolic diversities of soil microbial communities.
“The key measure to accelerate the restoration of the degraded ecosystems in the subtropical Karst region lies in increasing accumulation of soil OC by natural vegetation restoration or anthropogenic homologous practices.” ZHU suggested.
This project was supported by the Knowledge Innovation Program of Chinese Academy of Sciences (KZCX2-YW-T07 and KZCX2-XB3-10) and the National Natural Science Foundation of China (30970538, 30800162 and 411711246).
The result has been published on European Journal of Soil Biology (doi:10.1016/j.ejsobi.2012.03.003). The paper can be downloaded from http://www.sciencedirect.com/science/article/pii/S1164556312000283.