Accounting the Carbon Storage in Disturbed and Non-Disturbed Tropical Andean Ecosystems

Abstract

Global temperature has increased by about 0.7°C over the last century, a figure that is considered disproportionally large (Zhang et al., 1996). It is projected that climate changes will have profound biological effects, including the changes in species distributions as well as in carbon storage in forest ecosystems. The observed increase in emission of greenhouse gases, with attendant effects on global warming, have raised interests in identifying sources and sinks of carbon in the environment. A significant number of papers have demonstrated the history of the carbon dioxide content in the atmosphere over the last 4 billion years ant its relationship with the climatic history of the Earth, but it is less documented the effect of global warming on the carbon storage patterns in high Andean ecosystems. Recently, it has demonstrated that organic matter decomposition could increase under warmer climates, which may cause carbon flux and energy flow changes in alpine ecosystems (Kato et al., 2006). Simultaneously, Zhang et al., 1996 registered findings that are derived from a short– term responses to simulated environmental warming, focusing on aboveground biomass of three dominated life forms and community compositional attributes. Carbon storage in the Andean region involves different ecosystems such as the tropical montane cloud forests, the high-altitude wetlands, and the paramos ecosystem (Earle, et al., 2003, Pena et al., 2009). The total ecosystem carbon stock on these high mountains ecosystems is large and they are playing recently an important role in the global carbon balance. Although they cover only about 3% of the land area, they store about 30% of the global carbon storage of terrestrial ecosystems (IPCC, 2007). Most of the cover natural areas in the Andean regions are represented by paramos, high mountains, and wetlands (Pena et al., 2009). The paramo is a unique ecosystem of High Mountain between 3000 and 4800 meters above the sea level. The vegetation is composed of shrubs and grasses, and the thermal condition is continuously cool to cold, and relatively dry because of rain shadow effects from the surrounding mountains (Van Der Hammen, 1997). In the Andes, the paramo ecosystem ranges from Merida, Venezuela throughout Colombia, Ecuador down to Huancabamba (Peru). The low temperatures and the soil capacity to retain water lead this ecosystem to have a relatively low mineralization and nutrient recycling rates (Brady, N. & Weil, R., 2002; Lal, 2004). These features are related with the ability of paramos to sequester atmospheric