Corridor engineering is a common approach to protect wildlife. To mitigate the problem of elephant extinction ensuing, the Chinese government is creating the Asian elephant (Elephas maximus L.) conservation corridors under the support by the biodiversity conservation corridors initiative of Asian Development Bank (ADB). But the long-term effect of the corridors engineering on soil properties and functions recovery remain poorly investigated.
Prof. Cao Min and his team of Xishuangbanna Tropical Botanical Garden (XTBG) investigated the long-term performance (30 years) of two major forest types on which the corridor being built and one forest type built on rubber plantation in Xishuangbanna (21°09′–22°33′N, 99°58′–101°34′E), to compare the soil properties and functions recovery, including a natural secondary forest, an economic tree monoculture planting plantation, and an ecological replanting forest.
Their study found that on a 30-year basis, soil recovery differed significantly in the three regimes. The natural secondary forest regime had the best recovery result and the shortest recovery time. In contrast, the monoculture rubber plantation, despite constant fertilizer and management input, yielded the lowest recovery result and the longest recovery time.
From the perspective of soil recovery, the monoculture rubber plantation appeared unsustainable. However, the ecological replanting engineering improved soil recovery effectively and shortened the recovery time. Thus the corridor engineering by natural secondary forest regime or by ecological replanting forest regime can not only provide population and genetic exchange pathways for endangered Asian elephants in different small and fragmented patches, but also help for soil properties and functional recovery effectively.
In view of the conflict between biodiversity conservation and economic development, the researchers recommended that the combination of the ecological replanting and economic compensation be an effective measure for rain forest protection and restoration in tropical mountain regions of China.
The study entitled “Soil restoration potential with corridor replanting engineering in the monoculture rubber plantations of Southwest China” has been published in Ecological Engineering, 51: 169-177, http://dx.doi.org/10.1016/j.ecoleng.2012.12.081
