Logged forests support biodiversity after 15 years of rehabilitation
With the world facing global warming and a biodiversity crisis, a new study in Conservation Biology shows that within 15 years logged forests—considered by many to be 'degraded'—can be managed in order to successfully fight both climate change and extinction.
Studying regenerating forests in northeast Borneo, Dr. David Edwards from the University of Leeds, surveyed bird species in three different forests: a protected forest that had never been logged; a forest that had been logged and then actively rehabilitated over the last 15 years; and finally a forest undergoing natural regeneration after logging. Both forests were logged 20 years ago.
Through bird surveys, Edwards found that when a regenerating forest is supported by managed rehabilitation efforts, such as active tree-planting, it only requires 15 years for biodiversity to return to levels near those of unlogged areas. Naturally regenerating forest showed less diversity in the same time frame.
But in Southeast Asia many logged forests are quickly turned into plantations, such as palm oil and eucalyptus, whihc support little biodiversity when compared to forests.
Edwards says, "this [study] could act as a strong incentive to protect logged forests under threat of deforestation for oil palm and other such crops. Selectively logged rainforests are often vulnerable because they're seen as degraded, but we've shown they can support similar levels of biodiversity to unlogged forests."
Edwards further argues that his study proves carbon trading projects within rainforests, like REDD, should be linked directly to preserving biodiversity.
"Our research shows that it is possible to have both carbon sequestration and biodiversity benefits within the same scheme," Edwards says. "There are now suggestions that carbon crediting and 'biodiversity banking' should be combined, enabling extra credits for projects that offer a biodiversity benefit. We believe this should be introduced as soon as possible, to ensure maximum support for rehabilitation schemes in the tropical rainforest."
Comment by Alain Paquette
Although the title of this report makes sense, and as been the subject of numerous studies, it is not supported by the facts presented. My comment thus only concerns the report made on Mongabay.com of the study, not the study itself.
Edwards’ study did not include palm or eucalyptus plantations. But it did include a forest that was replanted, which actually showed biodiversity levels comparable to a natural forest and higher than a naturally regenerating one!
This then raises the question: “What is a plantation anyway?”. For Mongabay there seems to be one kind only: the bad ones (which were not tested in the study reported), therefore negating that the high biodiversity found in the managed forest under study was also obtained through planting trees. I’m afraid reality is a bit more complicated than the title suggests.
Plantations can have a very positive impact on biodiversity, resilience, and the provision of ecosystem services, which was demonstrated in the reported study and many times before. Plantations can of course also be very bad which, ironically, was not demonstrated in this study.
I know punchy titles are often necessary to get people’s attention, but more rigor at least in the reporting of study results will also be required, especially if we are to push towards the introduction of solutions such as REDD and clean development mechanisms that include plantations.
Issued by: Mongabay
Issue date: October 21, 2009
Link to Article: Origin of text