Scientists from the Carnegie Institution and WWF integrated satellite images, 3D vegetation-structure maps created using a LiDAR (light detection and ranging) system, and data from field plots to create high-resolution maps of 43,000 square kilometres of the Peruvian Amazon. They also combined historical data on deforestation and degradation with carbon stock information to calculate emissions from the Madre de Dios region between 1999 and 2009.

The researchers found that the total regional forest carbon storage was about 395 million tonnes, and that emissions reached about 630,000 tonnes per year. Forest degradation, such as selective logging, increased regional carbon emissions by 47 per cent over deforestation alone, although secondary regrowth compensated for 18 per cent of total gross emissions.

The study also revealed some unexpected results. ‘What really surprised us was how carbon storage differed among forest types and the underlying geology, all in very close proximity to one another,’ said lead author Greg Asner. ‘For instance, where the local geology is up to 60 million years old, the vegetation retains about 25 per cent less carbon than the vegetation found on geologically younger, more fertile surfaces. We also found an important interaction between geology, land use and emissions. These are the first such patterns to emerge from the Amazon forest.’ 

KARA MOSES
November 2010