Land‐use type and intensity differentially filter traits in above‐ and below‐ground arthropod communities

Abstract

Along with the global decline of species richness goes a loss of ecological traits. Associated biotic homogenization of animal communities and narrowing of trait diversity threaten ecosystem functioning and human well-being. High management intensity is regarded as an important ecological filter, eliminating species that lack suitable adaptations. Below-ground arthropods are assumed to be less sensitive to such effects than above-ground arthropods. Here, we compared the impact of management intensity between (grassland vs. forest) and within land-use types (local management intensity) on the trait diversity and composition in below- and above-ground arthropod communities. We used data on 722 arthropod species living above-ground (Auchenorrhyncha and Heteroptera), primarily in soil (Chilopoda and Oribatida) or at the interface (Araneae and Carabidae). Our results show that trait diversity of arthropod communities is not primarily reduced by intense local land use, but is rather affected by differences between land-use types. Communities of Auchenorrhyncha and Chilopoda had significantly lower trait diversity in grassland habitats as compared to forests. Carabidae showed the opposite pattern with higher trait diversity in grasslands. Grasslands had a lower proportion of large Auchenorrhyncha and Carabidae individuals, whereas Chilopoda and Heteroptera individuals were larger in grasslands. Body size decreased with land-use intensity across taxa, but only in grasslands. The proportion of individuals with low mobility declined with land-use intensity in Araneae and Auchenorrhyncha, but increased in Chilopoda and grassland Heteroptera. The proportion of carnivorous individuals increased with land-use intensity in Heteroptera in forests and in Oribatida and Carabidae in grasslands. Our results suggest that gradients in management intensity across land-use types will not generally reduce trait diversity in multiple taxa, but will exert strong trait filtering within individual taxa. The observed patterns for trait filtering in individual taxa are not related to major classifications into above- and below-ground species. Instead, ecologically different taxa resembled each other in their trait diversity and compositional responses to land-use differences. These previously undescribed patterns offer an opportunity to develop management strategies for the conservation of trait diversity across taxonomic groups in permanent grassland and forest habitats.

Climate change and intensive land use reduce soil animal biomass through dissimilar pathways

“…Land-use intensity also reduced the total biomass of microarthropods, but this negative effect was mainly due to lower densities in croplands than in grasslands. This is in accordance with other studies reporting negative effects of intensive land use (Baker, 1998; Birkhofer et al, 2017b) on the density of soil fauna, whereas the conversion from croplands to grasslands was shown to have positive effects (Zaitsev et al, 2006). Lower densities of soil fauna in croplands might be due to multiple detrimental effects, i.e., vegetation composition and mono-cropping, mechanical disturbance of the upper soil horizon, application of agrochemicals, and exposure to desiccation.…”

“…In this context, intensive land use is known to decrease the abundance and biodiversity of soil organisms (Bardgett and Van Der Putten, 2014; Flynn et al, 2009; Postma-Blaauw et al, 2010), consequently threatening the functioning of soils and the ecosystem services that they deliver, like soil fertility and nutrient dynamics (Beare et al, 1992; de Vries et al, 2013; Yin et al, 2019a), which may be fed back to primary production (Cardinale et al, 2004). Furthermore, intensive land use can have implications for trait diversity and the composition in above- and belowground arthropod communities (Birkhofer et al, 2017a). For example, frequent perturbations in intensive land use may select for soil microarthropods with particular life-history traits, such as r -strategists with high reproduction rates and small body size.…”

Trait‐based ecology of terrestrial arthropods

“…These effects have been observed across numerous taxa with diverse ecologies and spanning multiple trophic levels such as bees, beetles, butterflies, hemipterans, orthopterans, spiders (Börschig et al ., ; Rader et al ., ; Forrest et al ., ; Gámez‐Virués et al ., ; Mazzia et al ., ; Simons, Weisser & Gossner, ; De Palma et al ., ; Hanson et al ., ; but see Perović et al ., ; Le Provost et al ., ; Ng et al ., ), and soil‐dwelling arthropods in dozens of orders (Birkhofer et al ., ; Rigal et al ., ). By contrast, the effects of high‐intensity land use on the functional structures of arthropod communities may be buffered by landscape heterogeneity in relatively complex habitats such as forests (Edwards et al ., ; Gossner et al ., ; Gámez‐Virués et al ., ; Perović et al ., ; Birkhofer et al ., ; Gómez‐Cifuentes et al ., ; Murray et al ., ; Salas‐Lopez et al ., ; but see Martello et al ., ). It is important to note that most studies were conducted in temperate regions; additional studies incorporating varying landscapes and land‐use practices (grazing, logging etc.)…”

Restoring a butterfly hot spot by large ungulates refaunation: The case of the Milovice military training range, Czech Republic

“…Poorly mobile species were associated with the past military use. Among European butter ies, high mobility is a generalist trait associated with broad trophic ranges, long ight period and other features facilitating survival in human-dominated landscapes (Dapporto andDennis 2013, Bartonova et al 2014), whereas poor mobility increases extinction risks (Birkhofer et al 2017;Essens et al 2017). Because mobility relates inversely to local population density (Bartonova et al 2016), some poorly mobile species may need large habitat areas to sustain viable populations.…”