Direct and Indirect Effects of Forest Anthropogenic Disturbance on Above and Below Ground Communities and Litter Decomposition

Abstract

In order to understand the effect of disturbance on ecosystem functioning, one must take into account its indirect effects resulting from species interactions. While few empirical studies assess indirect effects and consider multiple trophic levels, recent statistical and theoretical advances provide new paths to do so. Here we investigate effects of disturbances in a boreal forest on multitrophic communities using a combination of the network and a trait-based approaches. Increasing functional diversity at different trophic levels is known to increase ecosystem functions, and disturbances may select for specific species traits. We therefore used structural equation modeling to quantify direct and indirect effects of environmental changes, on vegetation and soil fauna functional composition and on leaf litter decomposition. Forest disturbance intensity was found to have a bottom-up effect on species community composition, from lower trophic levels up to top predators. Disturbances also affected litter decomposition through changes of detritivore species composition. Such multitrophic assessments provide a more holistic understanding of ecosystem responses to environmental change.

Ecological Carrying Capacity Estimation of the Trails in a Protected Area: Integrating a Path Analysis Model and the Stakeholders’ Evaluation

“…Xiaoguanyin is under control, no severe root exposure or trail erosion was observed in most of the trails. However, the higher usage resulted in greater impacts on the biophysical environment (Table 4), which aligns with previous studies [21][22][23][24][41][42][43].…”

“…According to relevant studies [34][35][36]42,43], the impacts of usage on the biophysical environment might involve direct and indirect effects. In implementing practice, the consensus of the stakeholders is crucial [5,46].…”

“…Similar direct and indirect causal relationships between variables could also be found in the studies concerning anthropogenic disturbance in the natural environment. Laigle et al [42] established the causal model of forest harvesting on the composition of vegetation and soil fauna and their potential effects on leaf litter decomposition in forest ecosystems. From a broader scale, Yang et al [43] established the direct and indirect influence paths of the fundamental natural environment (soil type and topography), human activity (land use, population density, road impact, and night lights), and NDVI to climate change.…”

Impact of forest disturbance on microarthropod communities depends on underlying ecological gradients and species traits

“…Negative effects on soil functionality and diversity could affect bio-mediated soil processes, such as decomposition ( Marshall, 2000 ). Furthermore, changes in habitat vegetation and soil decomposer communities may have bottom-up effects, also affecting upper trophic guilds, such as predatory macroinvertebrates ( Laigle et al, 2021 ). Natural disturbances are extremely complex phenomena and interactions between wind-induced disturbance and other large-scale or micro-scale underlying ecological gradients might reduce or increase the effect on arthropod soil communities.…”

Divergent above‐ and below‐ground biodiversity pathways mediate disturbance impacts on temperate forest multifunctionality

“…Although timber harvesting could cause a reduction in stand structural diversity due to large stems removal, it could promote species diversity by creating forest gaps in which higher light resources might be available for saplings or colonizing seedlings (Molino & Sabatier, 2001). After a disturbance, large canopy gaps provoke great variations in light availability at the forest floor and, on soil temperature and water conditions (Laigle et al, 2021), and could promote higher tree species diversity through the niche partitioning of more greatly contrasting and frequently created resources and/or density effect (Sipe & Bazzaz, 1995). These gaps are expected to be occupied by early‐successional, light‐demanding species (Poorter & Bongers, 2006).…”