Dynamic effects of ground-layer plant communities on beetles in a fragmented farming landscape

Abstract

Vegetation effects on arthropods are well recognized, but it is unclear how different vegetation attributes might influence arthropod assemblages across mixed-agricultural landscapes. Understanding how plant communities influence arthropods under different habitat and seasonal contexts can identify vegetation management options for arthropod biodiversity. We examined relationships between vegetation structure, plant species richness and plant species composition, and the diversity and composition of beetles in different habitats and time periods. We asked: (1) What is the relative importance of plant species richness, vegetation structure and plant composition in explaining beetle species richness, activity-density and composition? (2) How do plantbeetle relationships vary between different habitats over time? We sampled beetles using pitfall traps and surveyed vegetation in three habitats (woodland, farmland, their edges) during peak crop growth in spring and post-harvest in summer. Plant composition better predicted beetle composition than vegetation structure. Both plant richness and vegetation structure significantly and positively affected beetle activitydensity. The influence of all vegetation attributes often varied in strength and direction between habitats and seasons for all trophic groups. The variable nature of plantbeetle relationships suggests that vegetation management could be targeted at specific habitats and time periods to maximize positive outcomes for beetle diversity. In particular, management that promotes plant richness at edges, and promotes herbaceous cover during summer, can support beetle diversity. Conserving ground cover in all habitats may improve activity-density of all beetle trophic groups. The impacts of existing weed control strategies in Australian crop margins on arthropod Abstract (247); Main text (6664); Acknowledgements (108); Abstract 21 Vegetation effects on arthropods are well recognized, but it is unclear how different vegetation attributes 22 24 Gibb H, Retter B, Cunningham SA, Barton PS (2017). Does wing morphology affect recolonization of 557 restored farmland by ground-dwelling beetles? Restoration Ecology 25:234-242 558 Goslee SC, Urban DL (2007). The ecodist package for dissimilarity-based analysis of ecological data. J Stat. 559

Mutual and Opposing Responses of Carabid Beetles and Predatory Wasps to Local and Landscape Factors in Vineyards

“…On the other hand, a negative effect of vegetation cover on carabids can as well be caused by a methodological bias, as a more complex and dense vegetation impedes carabid movement and reduces the probability of falling in the pitfall traps [80][81][82]. In some cases, plant functional composition is more suitable to explain carabid assemblages [38,77]. In our case, an enhancement of vegetation cover in vineyard inter-rows might not necessarily lead to an enhancement of carabid diversity or abundance.…”

“…The relationship between carabid communities and vegetation cover is complex. The effect sizes and directions of vegetation structure on carabid beetles can differ between seasons or trophic groups [77]. We expected vegetation cover to enhance feeding and hunting resources for carabid beetles and to provide more favorable microclimatic conditions [37].…”

Carabid community structure in northern China grassland ecosystems: Effects of local habitat on species richness, species composition and functional diversity

“…Vegetation composition and diversity also impact carabid community structure (Koricheva et al, 2000; Brose, 2003; Schaffers et al, 2008; Zou et al, 2013; Pakeman & Stockan, 2014; Ng et al, 2018a) and functional diversity (Liu et al, 2014; Pakeman & Stockan, 2014; Spake et al, 2016; Magura, 2017), because plants provide both shelter and food, directly (for herbivores) and indirectly (by providing prey for predators).…”

Influence of Climate and Local Habitat Characteristics on Carabid Beetle Abundance and Diversity in Northern Chinese Steppes

“…(5) Vegetation. Carabids should be favored (and hence attain higher abundance) in habitats with higher values plant biomass, density, height, and diversity, because more abundant, diversified, and complex (multilayer) vegetation should provide carabids with more microhabitats (including more food and shelter sites) [24][25][26][27][28].…”