The Leuser Ecosystem (LE) in the northern part of Sumatra, is one of the richest expanses of tropical rainforests in the world. Approximately 2.6 million hectares in extent, the Ecosystem stretches from the edge of the Indian Ocean almost to the shores of the Malacca Strait, and consists of magnificent lowland forests, alpine gardens, freshwater swamps, spectacular rift valleys, and several volcanoes.

Following on from the UN Conference on environment and development in Rio de Janeiro in which Indonesia signed the Agenda 21 in Rio Janeiro in 1992, thus was in need of serious protection.

Indonesian commitment for the conservation of the Leuser Ecosystem was manifested in the issuance of an unprecedented Presidential Decree No. 33/1998, which defined the extent of the Leuser Ecosystem and outlined the style of its management.

Apart for the unique and valuable biodiversity found in its forests, the Leuser Ecosystem provides life support functions for the sustainable development of more than four million people that live around it. These functions, sometimes called ecological services, have recently been valued at over 1.9 trillion Rupiah per year (Beukering and Caesar, 2000).

Ecological services provided by the Leuser Ecosystem include a regular clean water supply, erosion and flood control, germplasm, local climate regulation, carbon sequestration, fresh water fisheries, natural beauty (supporting a tourist industry), etc. These services can only be provided if the Leuser Ecosystem remains intact and continues to function as a whole interacting unit.

Threats to the Leuser Ecosystem and Regional Development

1.   Illegal logging increases greatly. (Approving new roads through conservation forests would in effect be facilitating illegal logging.)
2.  Poaching and trading in wildlife and commercial plants increase by several hundred per cent.
3.  Illegal resettlement and forest clearance occur for several kilometres on either side of the new road.
4.  Soil cover is quickly lost. (This is particularly noticeable in the Leuser Ecosystem where more than 95% of the total area is dominated by steep slopes.)
5.  Downstream areas suffer from flash floods in the wet season and from lack of water during the dry season.

Even if all the above problems could be controlled, local extinction of flora and fauna would still occur. This is because roads act as impassible barriers to many species of wildlife. The original forest is divided into smaller pieces - a process called fragmentation - and results in a reduction of biodiversity according to well known natural laws.