Kalimantan

Borneo, of which Indonesian Kalimantan covers two-thirds, is a single, vast-ecosystem in which the thick, exuberant forest that covers the world's third largest island acts as an enormous sponge. 

Formed over millions of years, the rainforest of Kalimantan is almost completely self-sustaining, requiring little more than water from the skies to survive. The soil on which the forest grows is thin and poor, and rather than drawing nutrients from the ground, it feeds on its own debris, recycling the nutrients contained in the rotting compost on the floor. Trees soar upwards, reaching a height of seventy meters or more, providing support for vines, creepers and orchids, and creating a dense canopy of leaves that protects the layer of humus from being washed away by the fierce tropical storms. While the thick cover of the forest blocks direct sunlight, rotting leaves and root mass store water from the rains, releasing it gradually during the dry season. Thus, the forest also creates and maintains the dark, warm, dank environment essential for its own continuous growth and that of the life within it.