Edge responses are different in edges under natural versus anthropogenic influence: a meta‐analysis using ground beetles

Abstract

Most edges are anthropogenic in origin, but are distinguishable by their maintaining processes (natural vs. continued anthropogenic interventions: forestry, agriculture, urbanization). We hypothesized that the dissimilar edge histories will be reflected in the diversity and assemblage composition of inhabitants. Testing this “history‐based edge effect” hypothesis, we evaluated published information on a common insect group, ground beetles (Coleoptera: Carabidae) in forest edges. A meta‐analysis showed that the diversity‐enhancing properties of edges significantly differed according to their history. Forest edges maintained by natural processes had significantly higher species richness than their interiors, while edges with continued anthropogenic influence did not. The filter function of edges was also essentially different depending on their history. For forest specialist species, edges maintained by natural processes were penetrable, allowing these species to move right through the edges, while edges still under anthropogenic interventions were impenetrable, preventing the dispersal of forest specialists out of the forest. For species inhabiting the surrounding matrix (open‐habitat and generalist species), edges created by forestry activities were penetrable, and such species also invaded the forest interior. However, natural forest edges constituted a barrier and prevented the invasion of matrix species into the forest interior. Preserving and protecting all edges maintained by natural processes, and preventing anthropogenic changes to their structure, composition, and characteristics are key factors to sustain biodiversity in forests. Moreover, the increasing presence of anthropogenic edges in a landscape is to be avoided, as they contribute to the loss of biodiversity. Simultaneously, edges under continued anthropogenic disturbance should be restored by increasing habitat heterogeneity.

Environmental filtering is the main assembly rule of ground beetles in the forest and its edge but not in the adjacent grassland

“…The main explanation for the observed random structure in our studied grassland patches is the asymmetrical species flow (spillover) across the forest edge (Magura, ). Forest edges maintained by natural processes (such as the studied ones) are penetrable for forest species, allowing them to move right through the edges and to disperse into the neighboring open habitats, while these same edges are inhospitable for grassland species (both open‐habitat and generalist ones), preventing them to penetrate into the forest interior (Magura et al ., ). Asymmetrical species flow of ground beetles between open habitats and neighboring forests regularly occurs (Magura et al ., ; Koivula et al ., ; Roume et al ., ; Brigić et al ., ; Lacasella et al ., ; Boetzl et al ., ; Schneider et al ., ; Yekwayo et al ., ), allowing the coexistence of grassland species and functionally and phylogenetically dissimilar forest species in the grassland.…”

“…Forest edges also have important functions regulating dispersal or invasibility (Ries et al ., ). Edges maintained mainly by natural processes inhibit the open‐habitat and generalist species to penetrate into the forest interior (Magura et al ., ). Unfavorable, human‐induced changes to their structure, composition and characteristics may alter their filter function, make them permeable, allowing the species from the surrounding, nonforested habitats to colonize the forest interior (Cadenasso & Pickett, ; Strayer et al ., ; Magura et al ., ).…”

“…The underlying mechanisms for these patterns may be the asymmetrical species flow across edges and strong environmental filtering. As a consequence, few open-habitat and generalist species from the adjacent grassland move into the forest edge and almost none of these cross the edge into the forest interior (Magura, 2017;Magura et al, 2017). The environmental filtering, both at the forest edge and in the interior, leads to communities composed of closely related, predominantly forest species with phylogenetically conserved traits.…”

“…Edges maintained mainly by natural processes inhibit the open-habitat and generalist species to penetrate into the forest interior . Unfavorable, human-induced changes to their structure, composition and characteristics may alter their filter function, make them permeable, allowing the species from the surrounding, nonforested habitats to colonize the forest interior (Cadenasso & Pickett, 2001;Strayer et al, 2003;Magura et al, 2017). Invasion by open-habitat and generalist species may cause the decline or local extinction of native forest specialists and facilitate or accelerate further invasion by alien species, that may lead to invasional meltdown (Green et al, 2011) and/or further habitat deterioration both in the edge and the interior (Murcia, 1995;Harper et al, 2005Harper et al, , 2015.…”

Linking microbial co‐occurrences to soil ecological processes across a woodland‐grassland ecotone

“…While patterns across ecotones have been observed for some soil parameters (e.g., moisture, temperature, carbon storage, etc.) and macrobiota in previous studies (Lacasella et al, 2015;Magura, 2017;Schmidt, Jochheim, Kersebaum, & Lischeid, 2017), little information is available on soil microbiome (Malmivaara-Lämsä et al, 2008).…”