Tree cover and its heterogeneity in natural ecosystems is linked to large herbivore biomass globally

Abstract

Addressing intertwined crises of climate change and biodiversity loss is a pressing global challenge, with trees playing pivotal roles in promoting carbon sequestration and habitat diversity. However, there is a distinct knowledge gap concerning the global drivers shaping tree cover and its heterogeneity, particularly the roles and relative importance of large herbivores and fire compared to climatic and topo-edaphic conditions. Here, we deploy satellite observations of strictly protected areas worldwide to reveal that in regions where vegetation may be in disequilibrium with climate, high biomass of large herbivores, especially browsers, is inversely related to tree cover but positively associated with its spatial heterogeneity. Conversely, fire reduces both tree cover and heterogeneity. These results suggest that top-down megafauna effects on landscape-scale vegetation openness and heterogeneity manifest worldwide. Our finding supports the need to consider megafauna, particularly large herbivores, in ecosystem effects on climate change mitigation and conservation and restoration efforts through trophic rewilding.

Keywords

vegetation openness; tree cover heterogeneity; landscape heterogeneity; large herbivores; megafauna; fire; top-down control; trophic cascade; alternative biome states; rewilding

Published in

One Earth
2023, Volume: 6, number: 12, pages: 1759-1770

SLU Authors

• Cromsigt, Joris

  • Department of Wildlife, Fish and Environmental Studies, Swedish University of Agricultural Sciences
    
  • Nelson Mandela University
  • Utrecht University

Associated SLU-program

SLU Plant Protection Network
SLU Forest Damage Center


UKÄ Subject classification

Ecology


Publication identifier

DOI: https://doi.org/10.1016/j.oneear.2023.10.007

Permanent link to this page (URI)

https://res.slu.se/id/publ/127426