Abstract:

Aims: This study aims to elucidate the variation in functional traits of soil Collembola along an elevation gradient in Populus davidiana and Betula platyphylla mixed forests on Guandi Mountains, as well as the effects of environmental factors on these functional traits. 

Method: We selected soil Collembola from the poplar-birch forest ecosystem of Guandi Mountains as the research subject. Four elevation gradients were set at 200 m intervals within the elevation range of 1,600–2,200 m, with three replicates per gradient, yielding a total of 12 sampling plots. Soil Collembola were collected using the dry funnel method. We identified and counted taxonomic groups, measured Collembola functional traits, and determined soil physicochemical properties to explore Collembola community characteristics and the spatiotemporal distribution patterns of their functional traits along the elevation gradient. Redundancy analysis (RDA) was applied to evaluate how soil environmental factors affect Collembola functional traits. 

Results: Soil Collembola abundance gradually decreased with rising elevation and exhibited an obvious epigeal aggregation pattern. Functional diversity indices differed significantly across elevations and seasons (P < 0.05). In summer, functional richness showed an overall increasing trend, whereas functional evenness, functional dispersion and Rao’s quadratic entropy (Rao’s Q) all decreased first and then increased. The community-weighted mean (CWM) of Collembola body length differed significantly among vertical soil layers (P < 0.05). The CWM values of body length, pigmentation, furca and scales showed significant seasonal dynamics (P < 0.05). Redundancy analysis demonstrated that soil temperature, pH and bulk density were significantly and positively correlated with Collembola body length, pigmentation, furca and ocelli.

Conclusion: This study clarifies the spatiotemporal distribution patterns and key environmental drivers of functional traits of soil Collembola on Guandi Mountains, and provides a theoretical basis for the conservation of soil fauna diversity in the poplar-birch forest ecosystem of Guandi Mountains.

Key words: poplar-birch forest, soil Collembola, functional traits, functional diversity, elevational gradient, environmental factors