Functional diversity increases the resistance of a tritrophic food web to environmental changes

Abstract

In the light of global climate change and biodiversity loss, understanding the role of functional diversity in the response of food webs to environmental change is growing ever more important. Using a tritrophic food web model, with a variable degree of functional diversity at each trophic level, we studied the role of functional diversity on the resistance of a system against press perturbations. Perturbations affected either nutrient availability or the mortality of the species, which can be interpreted as effects of eutrophication and warming, respectively. We compared food webs with different levels of functional diversity by investigating the species trait and biomass dynamics, the overall changes in the species’ standing biomass as measured by the warping distance, and the duration of the system transients after the onset of a press perturbation (transition time). We found that higher functional diversity increased resistance since it buffered trophic cascading effects and delayed the onset of oscillatory behaviour caused by either bottom-up forcing via perturbations to nutrient concentration or top-down forcing via perturbations to mortality rate. This increased resistance emerged from a higher top-down control of the intermediate species on the basal species. Functional diversity also promoted a higher top biomass, in particular via a higher proportion of top selective species undergoing high mortality rates. Additionally, functional diversity had context-dependent effects on warping distances, and increased transition times. Overall, this study encourages accounting for functional diversity in future investigations about the response of multitrophic systems to global change and in management strategies.

Environmental versus litter traits as drivers of microbial decomposer functions

“…Functional diversity serves as an indicator of litter communities' to environmental changes such as increasing temperatures and drought. Higher functional diversity enhances the ability to cope with or adapt to new conditions (Adje et al, 2023). Our results suggest that microbial decomposer communities will respond most strongly to shifts in plant community composition (i.e., changes in chemical litter traits) with regard to their functional diversity, rather than directly to meteorological changes.…”

“…Functional diversity in microbial communities can be an indicator for their ability to adapt to environmental changes such as increasing temperature and drought, as higher functional diversity indicates a broad set of functions present in the community that allows it to cope with new conditions (Adje et al, 2023;Wallenstein and Hall, 2012). The presence and proportion of generalists and specialists can modulate community responses, with generalists better mitigating the impact of environmental change (Clavel et al, 2011;Wallenstein and Hall, 2012).…”

Quantifying stability and resilience of eco-social keystone species complexes for coastal marine ecosystems of the Caribbean Sea and eastern Pacific: applications in conservation and monitoring programmes

“…In our case and based on the Routh-Hurwitz local stability criterion 1 (F s ) and the Levins' criterion to quantify resilience (F n ), we propose that this analytical strategy is useful for evaluating the current state and monitoring the trajectory exhibited by eco-social KSCs. In turn, the eco-social KSCs are constituted by a small set of components that represent ecosystems exposed to constant and multiple stressors affecting their structure and functioning within the context of global climate change [1][2][3][4][5][6].…”

“…The intensive and permanent impacts of human interventions on populations and coastal marine communities have escalated-irremediably-to the level of ecosystems, causing changes in their structures, dynamics and abilities to resist disturbances. This is important since it is occurring in the context of global climate change [1][2][3][4][5][6]. To address this problem, there are different scientific strategies that allow us to assess and predict the changes in natural systems, including: (i) those that reduce the objects of study to their minimum parts, assuming that the parts are more fundamental with respect to the wholes and assuming that the properties of the whole are simply an epiphenomenon of the properties of the parts; (ii) statistical analysis of factors, assigning relative weights and assuming that the factors which explore the greatest variances correspond to the main causes, tending to impose linear relationships (i.e.…”