Human Impacts and Climate Change Influence Nestedness and Modularity in Food-Web and Mutualistic Networks

PLoS One. 2016 Jun 20;11(6):e0157929. doi: 10.1371/journal.pone.0157929. eCollection 2016.

Abstract

Theoretical studies have indicated that nestedness and modularity-non-random structural patterns of ecological networks-influence the stability of ecosystems against perturbations; as such, climate change and human activity, as well as other sources of environmental perturbations, affect the nestedness and modularity of ecological networks. However, the effects of climate change and human activities on ecological networks are poorly understood. Here, we used a spatial analysis approach to examine the effects of climate change and human activities on the structural patterns of food webs and mutualistic networks, and found that ecological network structure is globally affected by climate change and human impacts, in addition to current climate. In pollination networks, for instance, nestedness increased and modularity decreased in response to increased human impacts. Modularity in seed-dispersal networks decreased with temperature change (i.e., warming), whereas food web nestedness increased and modularity declined in response to global warming. Although our findings are preliminary owing to data-analysis limitations, they enhance our understanding of the effects of environmental change on ecological communities.

MeSH terms

  • Climate Change*
  • Food Chain*
  • Human Activities*
  • Humans
  • Pollination / physiology
  • Seed Dispersal
  • Temperature

Grants and funding

This study was supported by a Grant-in-Aid for Young Scientists (A) from the Japan Society for the Promotion of Science (no. 25700030). The funder had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.