Tropical biodiversity on “a trajectory toward disaster”
Tropical biodiversity on “a trajectory toward disaster”
mongabay.com
June 26, 2008
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Despite recent debate over the extent of regenerating secondary forest cover, the effectiveness of protected areas and tropical extinctions protections, global biodiversity remains under great threat, warn scientists writing in the journal Frontiers in Ecology and the Environment.
Reviewing the current state of knowledge about tropical diversity and the looming continuing degradation of ecosystems, Corey Bradshaw and colleagues conclude “we are already squarely in the midst of a tropical biodiversity tragedy and on a trajectory toward disaster.” They urge adoption of the precautionary principle when it comes to making conservation decisions.
“The continued disappearance of habitat, soaring human population, and loss of vital ecosystem services demand immediate action,” the authors write. “the recent technical debate about likely extinctions masks the real issue — that, to prevent further loss of irreplaceable tropical biodiversity, we must err on the side of caution. We need to avoid inadvertently supporting political agendas that assume low future extinction rates, because this will result in further destruction of tropical biodiversity.”
 Bradshaw and colleagues cited research showing that some 15 million hectares of rainforest were destroyed on an annual basis during the 1990s. |
Bradshaw and colleagues note that while more than 60 percent of known biodiversity is found in the tropics, these regions face an onslaught of threats, including high population growth, poverty, poor governance and corruption, and “unprecedented” rates of habitat loss. Degradation and destruction of these ecosystems not only put biodiversity at risk but threatens human well-being.
“This is not just a tragedy for tropical biodiversity, this is a crisis that will directly affect human livelihoods,” said Bradshaw, Associate Professor at the University of Adelaide’s School of Earth and Environmental Sciences in Australia. “This is not just about losing tiny species found at the base of big trees in a rain forest few people will ever see, this is about a complete change in ecosystem services that directly benefit human life.”
 Market hunting is leaving some forests “empty” of key seed dispersers. |
“The majority of the world’s population live in the tropics and what is at stake is the survival of species that pollinate most of the world’s food crops, purify our water systems, attenuate severe flood risk, sequester carbon… and modify climate.”
Bradshaw and colleagues argue that valuing ecosystems for the services they provide will be a critical step to protecting them for the benefit of future generations. Already groups ranging from hedge funds the governments and indigenous groups are looking at ways — including the carbon market — to capitalize on the value of tropical habitats as living entities.
“We need to start valuing forests for all the services they provide, and richer nations should be investing in the maintenance of tropical habitats,” said Bradshaw, adding that improvements in governance would facilitate better management of resources.
“The greatest long-term improvements can be made in governance of tropical diversity resources and good governance will only come from strong multi-lateral policy. We need international pressure to ensure appropriate monitoring and accounting systems are in place,” Bradshaw concluded.
Corey JA Bradshaw, Navjot S Sodhi, and Barry W Brook (2008). Tropical turmoil: a biodiversity tragedy in progress. Frontiers in Ecology and the Environment 2009: 7, doi:10.1890/070193
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