As an attempt to mitigate anthropogenic climate change, planted forests have become a widespread restoration strategy across the globe. However, a new study led by the University of Bristol in the UK and the Federal University of Western Pará in Brazil has found that restoration initiatives using non-native tree species can have a significant impact on tropical insects in neighboring forests, disrupting their distribution and behavior. Thus, while well-intended, exotic tree plantations can have wider, unforeseen influences on the native biodiversity of hyper-diverse tropical forests.
In ecology, edge effect research focuses on how biological populations change at the boundary of two or more different habitats. In order to investigate the edge effects of newly planted Eucalyptus trees on native ecosystems in the Amazonian rainforest, the scientists collected over 3,700 dung beetles from 49 species.
“Our findings for dung beetles offer new insights into the importance of considering how proximity to exotic tree plantations can affect tropical forest biodiversity,” said Filipe França, a lecturer in Biology at the University of Bristol. “Importantly, edge effects varied across dung beetle responses and were species-specific. For example, we found more dung beetle species far away from Eucalyptus plantations, but some species also thrived and had higher abundances closer to plantation edges.”
These findings suggest that some dung beetles may be more sensitive to the introduction of new plant species close to their territories, while other, edge-affiliate and more generalist species, are able to thrive in novel environments.
“Understanding multi-species responses to anthropogenic disturbances is crucial to tackle the current biodiversity crisis and our findings are vital for forest managers and conservation planners aiming to maintain forest-specialist biodiversity in native ecosystems across the tropics,” concluded study senior author Rodrigo Ferreira Fadini, an expert in biodiversity at the Federal University of Western Pará.
The study is published in the journal Forest Ecology and Management.