Disentangling food-web environment relationships: A review with guidelines

Food webs represent the energy fluxes and the nutrient cycling between interacting species that underpin several ecosystem functions. Whether and how interactions vary across environmental gradients is still largely unknown. We reviewed the literature searching for systematic relationships between structural food-web properties and environmental gradients. Temperature and biotic factors are amongst the most frequently addressed drivers of food-web structure. We also assessed the degree to which food-web ecology has accomplished a mechanistic understanding of ecosystem functioning. We found that most studies are one-off descriptions of local food webs making it difficult to achieve an understanding of the response to human or environmental gradients. The lack of a consistent theory predicting how food webs change across environmental gradients, the diversity of objectives in food-web studies, and the absence of a standardized methodology for analysing them severely limit progress in the field. Moving forward requires the establishment of a core set of testable predictions, agreed standards for data collection and analysis, and the development of geographically distributed experimental studies of food-web dynamics. (c) 2022 The Author(s). Published by Elsevier GmbH on behalf of Gesellschaft fur Okologie.

Automated summary

Food webs and their relationship with environmental gradients are still largely unknown. The lack of consistent theories, diverse research objectives, and standardized methodologies severely limit progress in this field. Future efforts should focus on establishing testable predictions, agreed standards for data collection and analysis, and conducting geographically distributed experimental studies of food-web dynamics.