Clearance and fragmentation of tropical rain forest in Xishuangbanna, SW, China

Abstract

Xishuangbanna, situated in the northern margin of the tropical zone in Southeast Asia, maintains large areas of tropical rain forest and contains rich biodiversity. However, tropical rain forests are being rapidly destroyed in this region. This paper analyzed spatial and temporal changes of forest cover and the patterns of forests fragmentation in Xishuangbanna by comparing classified satellite images from 1976, 1988 and 2003 using GIS analyses. The patterns of fragmentation and the effects of edge width were examined using selected landscape indices. The results show that forest cover declined from 69% in 1976 to less than 50% in 2003, the number of forests fragments increased from 6,096 to 8,324, and the mean patch size declined from 217 to 115 ha. It was found that fragment size distribution was strongly skewed towards small values, and fragment size and internal habitat differ strongly among forest types: less fragmented in subtropical evergreen broadleaf forest, but severe in forests that are suitable for agriculture (such as tropical seasonal rain forest and mountain rain forest). Due to fragmentation, the edge width was smaller in 2003 than that in 1976 when the total area of edge habitat exceeded core habitat in different forest types. The core area of tropical seasonal rain forest was smallest among main forest types at any edge width. Fragmentation was severe within 12.5-km buffers around roads. The current forest cover within reserves in Xishuangbanna was comparatively large and less fragmented. However, the tropical rain forest has been degraded inside reserves. For conservation purposes, the approaches to establish forest fragments networks by corridors and stepping stone fragments are proposed. The conservation efforts should be directed first toward the conservation of remaining tropical rain forests.

Deforestation and fragmentation of natural forests in the upper Changhua watershed, Hainan, China: implications for biodiversity conservation

“…Increasing fragmentation and isolation has also found in most nature reserves of Hainan (>60 %) . A similar level of fragmentation was also found in the Xishuangbanna prefecture (Li et al 2009), and these small fragments had lower abilities to support enough species, especially endemic ones (Chang et al 2013). One of the ecological effects of fragmentation is increasing patch numbers which can lead to larger distances between habitat patches and hence greater habitat isolation (Hanski 1994).…”

“…This type of illegal deforestation, plantation expansion, and natural forests habitat fragmentation has also occurred in the nature reserves of the Xishuangbanna, another tropical region of China (Li et al 2007(Li et al , 2009. Fortunately, during the study period, the Hainan Provincial Forestry Department has increased its protected areas, with the aim to create a total of 3500 km 2 of protected area for forest and wildlife in Hainan by 2010 (Zhang et al 2010).…”

Urban Expansion and Its Impact on the Land Use Pattern in Xishuangbanna since the Reform and Opening up of China

“…Besides, forest became dispersed and less connected geographically in the last few decades. Consequently, the loss and fragmentation of natural forest leads to the reduction of wildlife habitat [65,66].…”

Change in Soil Microbial Community Compositions and Diversity Following the Conversion of Tropical Forest to Rubber Plantations in Xishuangbanan, Southwest China

“…Xishuangbanna, one of the richest regions in China, belongs to the Indo-Burma biodiversity hotspot (Myers, Mittermeier, Mittermeier, Da Fonseca, & Kent, 2000). However, the region's biodiversity is threatened by the dramatic land use or land cover changes in past 40 years, especially the decrease in natural forest cover from about 70% in the 1970s to 50% in the 2000s due to the expansion of rubber plantations (Li, Aide, Ma, Liu, & Cao, 2007;Li, Ma, Aide, & Liu, 2008;Li, Ma, 1 Rubber Research Institute, Chinese Academy of Tropical Agricultural Sciences, Danzhou City, P. R. China Liu, & Liu, 2009). The area of rubber monoculture plantations was 4.5% of the total area of Xishuangbanna in 1988Xishuangbanna in , 9.9% in 2002Xishuangbanna in , and 22.2% in 2010, and rubber monoculture expanded to higher elevations and onto steeper slopes between 1988 and 2010 (Chen et al, 2016).…”