Tree Diversity Mediates the Distribution of Longhorn Beetles (Coleoptera: Cerambycidae) in a Changing Tropical Landscape (Southern Yunnan, SW China)

Abstract

Longhorn beetles (Coleoptera : Cerambycidae) have been used to identify sites of high biological diversity and conservation value in cultivated landscapes, but were rarely studied in changing landscapes of humid tropics. This study was conducted in a region of southern Yunnan, China, which was dominated by natural rainforest until 30 years ago, but is successively transformed into commercial rubber monoculture plantations since that time. The objectives were to investigate longhorn beetle species diversity and distribution in the major land use types of this landscape and to estimate the effects of an expected expansion of rubber plantations on the longhorn beetle assemblages. The results showed that tree species diversity (181 species in total) and longhorn beetle diversity (220 species in total) were closely related with no significant differences between the tree and longhorn beetles assemblages shown by similarity distance analysis. There was a highly positive relationship between the estimated species richness of longhorn beetles and the number of tree species. Individual numbers of longhorn beetles and trees were also highly positive related at the sampling sites. Non-metric multidimensional scaling revealed that the degree of canopy coverage, succession age and tree diversity explained 78.5% of the total variation in longhorn beetle assemblage composition. Natural forest sites had significantly higher numbers of species and individuals than any other type of habitat. Although young rubber plantations bear the highest longhorn beetle diversity outside forests (half of the total number of longhorn beetle species recorded in total), they can not provide permanent habitats for most of these species, because they develop into closed canopy plantations with less suitable habitat conditions. Therefore, along with an expected expansion of rubber cultivation which largely proceeds at the expense of forest areas, the habitat conditions for longhorn beetles in this region might decrease dramatically in future.

Movement patterns of selected insect groups between natural forest, open land and rubber plantation in a tropical landscape (southern Yunnan, SW China)

“…Therefore, the recorded tendency of this group of species to move out of the forest might be induced by the additional resource requirements of adults. The lower number of species and individuals in the rubber plantation edge traps may indicate that rubber monocultures are not accepted as habitat, supporting the finding that longhorn beetle diversity in this tropical region is mediated by tree diversity (Meng et al 2013). In contrast, bark beetle distribution showed no significant difference between forest and rubber plantation edge traps, which might be explained by lower tree habitat quality requirements and higher dispersal ability.…”

Distribution of long-horn beetles (Cerambycidae: Coleoptera) within the Fijian archipelago

“…Finally, Cerambycidae have potential as excellent bioindicators of forest 'health' due to their diversity, range of habitat specificities, and the multiple ecological roles they play, such as pollination, decomposition and as food for forest birds (Hanks 1999;Dajoz 2000). From a practical viewpoint, they can be relatively easy to identify, and there are already studies linking Cerambycidae diversity with floral diversity (Meng et al 2013) and biodiversity 'hot spots' (Holland 2007). Together with other recent papers proposing the use of Fijian invertebrates as bioindicators of habitat integrity and ecosystem 'health' (e.g.…”

Diversity and abundance of longhorn beetles (Coleoptera: Cerambycidae) in Gunung Walat Educational Forest, West Java, Indonesia

“…Although many species of longhorn beetle live in a wide range of plants, some species live only in or on a certain host plant (Noerdjito 2011). Meng et al (2013) reported that there was a positive relationship between the number of longhorn beetle species and the number of tree species in a habitat. The diversity of trees reflected the availability of different types of dead wood.…”