Degraded rainforests still hold significant value, new study shows

Rain forest canopy, Malaysia

The findings challenge the common perception of these forests as ecological wastelands, instead revealing clear thresholds where proactive and reactive conservation efforts can be most effective. 

The research involved scientists from 85 organisations around the world, including several staff and students from Queen Mary University of London’s School of Biological and Behavioural Sciences, and analysed data on over 1,600 species across 86 taxonomic orders and 126 functional groups in a rainforest in Malaysian Borneo that had experienced varying degrees of logging. 

The study revealed a surprising value of lightly logged forests. Even areas that have lost up to 30% of their trees still hold impressive levels of biodiversity and function ecologically, which suggests these areas could be immensely valuable additions to conservation efforts. 

The research also pinpointed two critical points for guiding conservation strategies. When less than 30% of the biomass is lost, proactive measures like creating protected areas prove most effective. However, for areas that have suffered more significant losses, exceeding 68% biomass loss, a shift in approach is necessary. Here, restoration efforts like planting new trees and controlling invasive species, become more crucial. 

Dr Pavel Kratina, Senior Lecturer in Ecology, stated "Our group investigated how feeding interactions of bat predators change across the gradient of rainforest degradation. The data on bat communities we contributed to the study provided a critical piece of the puzzle in understanding how logging impacts the entire food webs. One of the study’s findings is that dietary specialists are disproportionately more impacted by selective logging than generalist predators." 

Professor Stephen Rossiter, whose PhD students undertook fieldwork at the study site, added that "by providing abundance data on leeches, arthropods, and bats, our results have helped to uncover a complex picture of contrasting responses to forest degradation, and added to the overall findings of the study." 

Dr Tom Fayle, Senior Lecturer in Ecology, explains their contribution: "Ants are an ecologically important group in tropical forests, turning over soil, forming mutualisms with some species, and eating others. We studied how ant communities respond to habitat degradation. The bringing together of data on different groups of species from so many different research groups makes this a particularly exciting study and is something that has not been previously attempted at this scale." 

All this input from different research groups shows that degraded forests, while not the same as untouched primary forests, still hold considerable value for conservation.  

The study calls for a shift in how we view and manage these forests. By recognising their remaining value and implementing targeted conservation strategies, we can secure the health and functionality of these vital ecosystems for years to come.