Geographically, the island is divided into central plateau that extends diagonally from Sabah (Malaysia) in the northeast of Borneo to the southwest Borneo, roughly forms the boundary between West and Central Kalimantan (Indonesia). The mound is not the fiery mountains across Borneo, there is only one volcano that has been dead-but is the highest mountain in Southeast Asia: Mount Kinabalu in Sabah, whose height reaches 4095 meters (13 435 feet).
The forests of Borneo are some woods that have the most biodiverse on the planet. According to WWF, the island is estimated to have at least 222 species of mammals (44 of them endemic), 420 birds were settled (37 endemic), 100 amphibians, 394 fish (19 endemic), and 15,000 plants (6,000 endemic)-more than 400 of which have discovered since 1994. Surveys have found more than 700 species of trees on 10 acres-a number equal to the number of trees in Canada and the United States combined.
Lowland dipterocarp forest in Borneo forest is the most diverse and most threatened residents (68% has been cleared in the lowlands of Borneo, 65% in Malaysia). These giant trees, usually higher than 45 meters, is a source of timber most valuable in Borneo and have been heavily logged for 3 decades. Langner and Siegert (2005) estimated that only less than 30 million hectares of lowland dipterocarp forest remaining in Borneo in 2002.
The prevalence dipterokarpas gives Borneo's forests are highly unusual dynamics associated with marine atmospheric phenomenon called El Ni? O-Southern Oscillation (ENSO or also known as "El Nino"). According to Lisa Curran, a biological spent more than 20 years in Borneo and is now a leading expert on the natural history of the island, reproduction dipterocarp extremely unlikely released from the coming El Nino, with 80-93% of species flowering time equating them with the weather conditions dry, which usually appear within a period of 4 years. During the dipterocarp Borneo, canopy-canopy into colorful, as thousands of dipterocarp trees and every tree may have 4000 flowers bloom during the 6 weeks, alternately starve and fill in seed predators, until at least some seedlings survived until the germination.
Mass flowering and fruiting seasons followed-known will be the same in the area of 150 million hectares (370 million acres) and involves 1870 species-is a boon to seed predators, including wild boar, the seed predator in the ecosystem. Seeds and wild boar are so prevalent at this time, to the local residents saw the arrival of El Nino as times of plenty, when to harvest beans for export illipe or filling up with pork. The relationship has lasted as long as humans have lived in Borneo and is ingrained in the culture of society, ranging from tribal to coastal traders.
However, in recent years, the system seems to be breaking down due to changes in land use. Dr. Curran, who was awarded a MacArthur Genius Award 2006 for her work in this area, said that intensive logging has been paid handsomely by the reproductive cycle. Curran found that seed production fell from 175 pounds per acre in 1991 to 16.5 pounds per acre in 1998, even though it was during El Niño years on record. It seems that logging has reduced the local density and biomass of mature trees below a critical threshold.
Furthermore, the introduction of fires in the area that had no experience burning, has exacerbated the drought stress and causing a radical transformation in forest ecology. Currently, el Nino year is no longer a time of plenty. As Curran said during a visit to California, El Nino has been a great destroyer instead of the great. Land use change has ruined what was once a closely related ecosystems.
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