Scale-dependent contribution of biotic and abiotic factors to longhorn
beetles (Cerambycidae) community composition variation at the Indo-
Burma biodiversity hotspot
Abstract
Despite centuries of exploration, our perception of potential mechanisms
determining the species community assemblage is still in infancy .
Longhorn beetle as an insect with larval stage feeds on the xylem of
plants or trees, the relative importance of biotic (host-specificity)
and abiotic (climate gradients) processes to determining their community
compositional variation is unknown. In the aim of exploring the knot, we
therefore designed the experiment throughout multiple spatial scales
(macro/regional and micro/local) along tropical to temperate climate
gradients at the Indo-Burma biodiversity hotspot, to examine to what
extent biotic and abiotic factors may exert a significant influence on
longhorn beetle species composition assembly, and whether this
relationship is scale dependent. The relationships between longhorn
beetles species composition variation and biotic and abiotic factors
were examined using β-dissimilarity indices comparison,NMDS analysis ,
variation partitioning based on RDA, linear mixed-effect model and
mantel test. We found a positive relationship between the species
compositional variation of both beetle and plants, in which longhorn
beetle species dissimilarity apparently track changes in plant
dissimilarity both at macro/regional and micro/local scales. NMDS
analysis showed that abiotic factors have prominent influence to the
longhorn beetle community assemblage. Variation partitioning and linear
mixed-effect model retained significantly correlated Environment and
plant diversity metrics for beetle diversity. Thus, we concluded that:
1) biotic and abiotic factors collaboratively shaped longhorn beetle
community composition along various spatial scales; 2) the relative
importance of abiotic and biotic variation explaining the longhorn
beetle community composition vary by spatial scale; and 3) biotic
interactions have prominent effect to longhorn beetle community
composition at local-scale while macroclimatic gradients impose the most
control on it at macro-scale. Besides, our study showed that the
influence of dispersal limitation in the species assembly of longhorn
beetles from tropical to temperate area was minor compared with plant
communiti