Mapping reveals targets for preserving tropical carbon stocks

An image from the Peru-wide, high-resolution carbon map showing the effects of deforestation (blue; no more carbon remaining) into a region of ultra-high carbon stocks in the surrounding forest (red). 

You can see massive losses in the bustling city of Pucallpa (right side) and the thousands of small farmers spreading into the forest to the west of Pucallpa. Image courtesy of Greg Asner. 

Credit: Greg Asner

A new high-resolution mapping strategy has revealed billions of tons of carbon in Peruvian forests that can be preserved as part of an effort to sequester carbon stocks in the fight against climate change.

Tropical forests convert more carbon from the atmosphere into biomass than any other terrestrial ecosystem on Earth.

However, when land is used for agriculture, as a wood source, or for mining, carbon is often released into the atmosphere where it contributes to climate change.

Tropical deforestation and forest degradation account for about 10 percent of the world's carbon emissions annually.

There remain major challenges to conserving the carbon that's stored in these tropical landscapes on a national and international scale.

A team led by Carnegie's Greg Asner developed a new high-resolution approach for prioritizing carbon conservation efforts throughout tropical countries.

Their findings are published the week of November 10 in the Proceedings of the National Academy of Sciences.

The team of authors emphasized that the low cost of conducting their project means that the same approach can be rapidly implemented in any country, thereby supporting both national and international commitments to reduce and offset carbon emissions.

Many of the geographic details about the carbon that's stored in tropical forest ecosystems remain unknown.

For thos involved in conservation efforts to select new areas in which carbon stocks can be best protected and enhanced, detailed information on which areas would make the best targets for protection are necessary. This means understanding each landscape's climate, topography, geology, and hydrology.

Using advanced three-dimensional forest mapping data provided by the Carnegie Airborne Observatory (CAO), integrated with satellite imaging data, the team was able to create a map of carbon density throughout the 128 million hectare (320 million acre) country of Peru, at a resolution of one hectare (2.5 acres).

"We found that nearly a billion metric tons of above-ground carbon stocks in Peru are at imminent risk for emission into the atmosphere due to land uses such as fossil fuel oil exploration, cattle ranching, oil palm plantations and gold mining," Asner said.

"The good news is that our high-resolution mapping was able to identify three strategies for offsetting these upcoming emissions."

More information: Targeted carbon conservation at national scales with high-resolution monitoring, PNAS, www.pnas.org/cgi/doi/10.1073/pnas.1419550111

Saviour of the Coral Reefs: Sea Cucumbers

Sea cucumbers can save coral reefs from the impact of ocean acidification on their growth, a group of scientists working on the impact of climate change on coral reefs have revealed in a recent study.

The research, published in the latest issue of the Journal of Geophysical Research, suggests that calcium carbonate released from the digestion of sand by sea cucumbers, one of the largest invertebrates found on tropical reefs, is a key component for the survival of coral reefs.

Maria Byrne, professor and director, One Tree Island Research Station of the University of Sydney on the Great Barrier Reef, said that coral reefs must accumulate CaCO3 at a rate greater than or equal to the CaCO3 that is eroded from the reef to survive.

Byrne, who is the lead author of the research, writes in the journal: "The research at One Tree Island showed that in a healthy reef, dissolution of calcium carbonate sediment by sea cucumbers and other bio-eroders appears to be an important component of the natural calcium carbonate turnover."

NASA: Carbon Stored in Earth's Tropical Forests

Benchmark map of carbon stored in Earth’s tropical forests, covering about 2.5 million hectares of forests over more than 75 countries.

The map can assist efforts by countries to produce estimates of carbon emissions by providing relatively fine-scale stocks of carbon and their level of uncertainty.

Image credit: NASA/JPL-Caltech/UCLA/Winrock International/Colorado State University/University of Edinburgh/Applied GeoSolutions/University of Leeds/Agence Nationale des Parcs Nationaux/Wake Forest University/University of Oxford

Beruli Ulcers: The WHO Needs to seriously re-think it's strategy

Buruli ulcers, one of the ‘neglected tropical diseases’ left aside by big pharma and governments alike, are reasonably well treatable, also in poor regions but then more attention has to be paid to early diagnosis and correct treatment.

This means the rules of the World Health Organization urgently need to be changed. So say scientists of the Antwerp Institute of Tropical Medicine (ITM), based on ten years of research in Congo.

The disease is caused by Mycobacterium ulcerans, a nephew of the infamous tuberculosis bacterium. It occurs in tropical and subtropical countries, mainly in Africa. It causes hideously ulcerating ‘holes’ in the skin, that can dig to the bone and can outgrow to diameters of more than 10 centimetres.

Much about the disease is unknown, for instance how exactly people get infected. It is assumed that water plays a role, but only in 2008 scientists — at ITM — succeeded in cultivating the bacterium from a water insect.

For a long time the only treatment consisted of caring for the wounds, and possibly a skin transplantation. Nowadays the WHO proposes a treatment analogous to tuberculosis, with two antibiotics, rifampicin and streptomycin. This works for light cases, but for lesions above 10 cm the effect was not documented.

ITM scientist Anatole Kibadi Kapay collected cases in DR Congo from the previous five years, when surgery combined with antibiotics was used, and from the five year before that, when only surgery was used. In the process he discovered a new focus close to the Angolan border; he assumes it to be correlated to the working conditions in the illegal diamond mines there.

Kibadi Kapay noticed that the WHO guidelines for clinical diagnosis lead to a correct diagnosis in only 2 cases out of 3. As opposed to a Ziehl-Neelsen smear, a microscopic technique that is within reach of poor countries — and that, through a better diagnosis, prevents the needless use of antibiotics.

But when large wounds have to be treated, from a microscopically confirmed Buruli case, antibiotics indeed are of good use. With surgery only, 15% of patients relapse; with parallel use of antibiotics, less than 2% relapse. But antibiotics only, without surgery, make large wounds worse.

Kibadi Kapay — who today received a doctorate from Antwerp University for his work — and his ITM colleagues advocate faster surgery of large ulcerating lesions, without four weeks of waiting with antibiotics only.

The more because patients themselves already wait a long time before consulting a doctor — to them the ulcers are inflicted by witchcraft or fate.

The research by Kibadi Kapay demonstrates the need of a better education of the population, but more important, it shows that WHO guidelines for diagnosis and treatment of Buruli ulcers urgently need to be adapted.

Global Warming: Protecting the Maldives

Global Warming holds the greatest threat for these idyllic atolls in the Indian Ocean