Invertebrate functional traits and terrestrial nutrient cycling: Insights from a global meta‐analysis

Functional traits are useful for characterizing variation in community and ecosystem dynamics. Most advances in trait‐based ecology to date centre on plant functional traits, although there is an increasing recognition that animal traits are also key contributors to processes operating at the community or ecosystem scale. Terrestrial invertebrates are incredibly diverse and ubiquitous animals with important roles in nutrient cycling. Despite their widespread influence on ecosystem processes, we currently lack a synthetic understanding of how invertebrate functional traits affect terrestrial nutrient cycling. We present a meta‐analysis of 511 paired observations from 122 papers that examined how invertebrate functional traits affected litter decomposition rates, nitrogen pools and litter C:N ratios. Based on the available data, we specifically assessed the effects of feeding mode (bioturbation, detritus shredding, detritus grazing, leaf chewing, leaf piercing, ambush predators, active hunting predators) and body size (macro‐ and micro‐invertebrates) on nutrient cycling. The effects of invertebrates on terrestrial nutrient cycling varied according to functional trait. The inclusion of both macro‐ (≥2 mm) and micro‐invertebrates (