Study: Old-Growth Trees Store Up To Half Of All Carbon In Tropical Rainforests
Large trees store store up to half the above-ground biomass in tropical forests, reiterating their importance in buffering against climate change, finds a study published in Global Ecology and Biogeography.
The research, which involved dozens of scientists from more than 40 institutions, is based on data from nearly 200,000 individual trees across 120 lowland rainforest sites in Africa, Asia, and Latin America. It found that carbon storage by big trees varies across tropical forest regions, but is substantial in all natural forests.
African rainforests, with an average of 418 tons of above-ground biomass per hectare, stored the most carbon. Big trees — defined as those measuring at least 70 cm in diameter at breast height — accounted for an average of 44 percent of African forests' biomass. Other research has suggested that the preponderance of large trees in African forests is due to the abundance of large herbivores, which suppress smaller trees.
Asia was second with an average of 393 tons, of which large trees accounted for 154 tons or 39 percent of total above ground carbon. Latin America averaged 288 tons per hectare, about a quarter of which occurred in large trees.
EDIT
http://news.mongabay.com/2013/0807-big-trees-biomass.html