Tropical rainforests play an important role in the exchange of gases such as carbon monoxide, carbon dioxide, methane and oxygen between the biosphere and the atmosphere. Over 650 species of plants with pharmaceutical properties and economic value have been discovered in the Amazon, thanks to the help of tourists and developers, and countless more wait. Ecotourism is a low-impact sustainable economic activity that combines environmental preservation with socioeconomic needs of the local populations. It also provides viable income to the Amazon and also brings benefits such as improvements in health, education, technical assistance and training as well as community participation in the decision-making process. That is important because government recourses are extremely scares. Ecotourism also creates jobs for local communities such as tour guides and vendors, selling such things as cultural representations or basketry.