Tree diversity is influenced by large herbivores: Study
California, US: A study team has mapped the tree cover of the world's protected regions using global satellite data.
According to the study, areas with a high concentration of large herbivores in various environments tend to have a more diverse tree cover, which is predicted to enhance biodiversity in general.
Preserving biodiversity and reducing climate change requires the maintenance of ecosystems that are resilient and rich in species. Megafauna or the portion of an area's animal population made up of the largest creatures, is crucial in this situation.
An international research team, including Lund University, has examined the complex interactions between the variety of trees and the number of ravenous herbivores in the world's protected regions in a new study that was published in the scientific journal One Earth.
"Our findings reveal a fascinating and complex story of how large herbivorous animals shape the world's natural landscapes. The tree cover in these areas is sparser, but the diversity of the tree cover is much higher than in areas without large herbivores," said Lanhui Wang, a researcher in physical geography and ecosystem science at Lund University.
"In our global analysis, we find a substantial association between the biomass of large herbivores and varied tree cover in protected areas, notably for browsers and mixed-feeders such as elephants, bison and moose and in non-extreme climates", explained the study's senior author, Jens-Christian Svenning, professor at Aarhus University.
Hereby, the study supports that large wild herbivores promote a diverse vegetation structure, creating a rich habitat for many other species. This is due to the animals' consumption of vegetation as well as physical disturbances.
According to Lanhui Wang, these new research findings highlight the need to integrate large herbivores into restoration and conservation strategies. Not only for the sake of the animals themselves but also for the vital role they play in shaping landscapes and influencing biodiversity.
The researchers argue that this aspect is not sufficiently considered within the framework of sustainable land management and ecosystem restoration.
"At a time when global initiatives are intensely focused on combating climate change and biodiversity loss, our findings highlight the need for a broader and more nuanced discussion about ecosystem management and conservation measures. It is of utmost importance to integrate understanding of the ecological impact of megafauna into this," said Lanhui Wang.
The UN has declared the 2020s as the decade of ecosystem restoration. In total, 115 countries have agreed to restore up to 100,000 square kilometres of nature in total. To achieve this, more wild-living large herbivores are needed worldwide, said Lanhui Wang.
"I believe that we will need to protect and conserve large herbivores to achieve the UN goals. Megafauna are crucial for tree cover, which in turn promotes carbon sequestration and a diversity of habitats," said Lanhui Wang.