Spatio-temporal heterogeneity differently drives the diversity of various trophic guilds of mesofauna in semi-arid oak forests

Abstract: Despite the importance of mesofauna in soil formation, litter decomposition, biological cycles and growth of plants for semi-arid forest ecosystems, the effects of different woody species and seasonality on the abundance, diversity and composition of mesofauna invertebrates have been little studied. This study has evaluated the effects of woody species (trees and shrubs) on trophic guilds of abundance, diversity and composition of soil mesofauna (detritivores vs. predators) during spring and winter seasons. Moreover, the basic drivers, including microclimatic characteristics and soil properties, of abundance, diversity and composition of soil biota have been identified in semi-arid deciduous broadleaved forests. Woody species types and seasonality affected soil mesofauna abundance, diversity and composition (non-metric multidimensional scaling; NMDS). All the species were present during spring and winter and in all types of woody species, but the mesofauna abundance, diversity and composition were differently influenced by the season and woody cover. Predator abundance was affected by both species and seasonality, whereas detritivore abundance was only influenced by woody species. Detritivore and predator diversity was affected by woody species and seasonality, but not by the interaction of both factors. It has been also demonstrated that the understory of trees is more important as biodiversity hotspot for mesofauna activity compared to shrubs; moreover, the mesofauna composition (detritivores vs. predators) is driven by the seasonality and woody species. Overall, this work has demonstrated that plants and soil organisms are strictly linked to each other and aboveground and belowground communities can be powerful mutual drivers. Graphic abstract: [Figure not available: see fulltext.]