Observational study reveals a trimodal beta-diversity pattern across elevational gradients in montane butterflies, highlighting the conservation value of vegetation ecotones.
Key Points
To determine the elevational distribution patterns of butterfly alpha- and beta-diversity and identify the key environmental mechanisms shaping community structure across a mountain gradient.
Established 18 standardized 1000 m transects at 200 m intervals across an elevational gradient from 1000 m to 4500 m.
Surveyed butterfly species richness and abundance using the standardized line-transect method.
Butterfly species richness and abundance decreased significantly with increasing elevation.
Beta-diversity exhibited a nonlinear trimodal pattern with three distinct peaks at 1900–2300 m, 3500–3900 m, and 4300–4500 m.
Distribution patterns were driven by vegetation ecotone effects, habitat heterogeneity, elevational species turnover, and microclimatic variation.