Landscape diversity promotes stable food‐web architectures in large rivers

Abstract

Uncovering relationships between landscape diversity and species interactions is crucial for predicting how ongoing land‐use change and homogenization will impact the stability and persistence of communities. However, such connections have rarely been quantified in nature. We coupled high‐resolution river sonar imaging with annualized energetic food webs to quantify relationships among habitat diversity, energy flux, and trophic interaction strengths in large‐river food‐web modules that support the endangered Pallid Sturgeon. Our results demonstrate a clear relationship between habitat diversity and species interaction strengths, with more diverse foraging landscapes containing higher production of prey and a greater proportion of weak and potentially stabilizing interactions. Additionally, rare patches of large and relatively stable river sediments intensified these effects and further reduced interaction strengths by increasing prey diversity. Our findings highlight the importance of landscape characteristics in promoting stabilizing food‐web architectures and provide direct relevance for future management of imperilled species in a simplified and rapidly changing world.

Glaciers, snow, and rain: Water source influences invertebrate community structure and secondary production across a hydrologically diverse subarctic landscape

“…In addition, because we focused our sampling on riffle microhabitats, the sites typically have the highest production within streams (Buffagni and Comin 2000), we were unable to represent variation in community structure or production between different microhabitats within a study reach. Regardless, the results highlight the need to better understand spatial and seasonal heterogeneity in secondary production at the landscape scale (Cross et al 2013;Scholl et al 2023).…”

“…Using this approach, we resampled size-specific abundances of each taxon from each site by date with replacement 1000 times to create an array of size distribution estimates. We then used each resampled array to estimate secondary production using the size-frequency approach to generate a vector of biomass, abundance, and production estimates along with their variance (Cross et al 2013;Scholl et al 2023). We estimated production for most taxa at the family-level using the sizefrequency method corrected for cohort production interval (Benke and Huryn 2017).…”

Disturbance theory for ecosystem ecologists: A primer

“…Biological diversity plays a key role in the stabilization of cellular to landscape processes and is therefore a central determinant of disturbance response across scales of biological organization. For example, functionally redundant gene products provide "functional buffering" at the cellular level; response mechanism diversity (Elmqvist et al, 2003) and genetic diversity (Schippers et al, 2015) provide analogous landscape-scale stability following disturbance (Frelich & Reich, 1999;Kellner et al, 2009;Li et al, 2003;Scholl et al, 2023).…”

Predicting emergent animal biodiversity patterns across multiple scales

“…When a model aims to predict biodiversity responses to novel environmental changes this individual detail and the spatial heterogeneity of landscapes at species‐relevant scales can be crucial. For instance, adaptive foraging by consumers has a key role in stabilising complex food webs (Kondoh, 2003) and habitat diversity has been linked to higher prey production and stabilising trophic interactions (Scholl et al., 2023).…”