The triangular watershed stretches from Gingee to Marakkanam to the Auroville plateau, and covers an area of 740 sq. km. or 25,000 ha. During the monsoons runoff water reaches the Kaliveli floodplain (which is the lowest point within the watershed) via an intricate network of tanks and channels.


TDEF site distribution close to kaliveli region

Each region of the world has a vegetation type that has, over countless eons, evolved as the plant community most suited to the environmental conditions of the area. The Tropical Dry Evergreen Forest (TDEF) is the indigenous forest of the coastal seaboard of South East India. Historically the forest extended from Vishakapatanam to Ramanathapuram as a belt of vegetation between 30 and 50 km wide, bordered on one side by the sea and on the other side by a forest that becomes increasingly deciduous as one moves inland.

It contains over 160 woody species of which around 70 are found within the pristine climax forest. This is predominantly composed of trees and shrubs that have thick dark green foliage throughout the year. There are six vegetative elements: trees, shrubs, lianas, epiphytes, herbs, and tuberous species. In the pristine state these components weave together to form a complex diverse habitat that is home to a myriad of animal species, mammals, birds, reptiles, amphibians, insects, as well as a host of microbes.

When one includes all of the herbaceous species that grow in a variety of ecological niches within the range of the forest the number of species approaches 1000, of which over 600 have a recorded use for mankind either medicinally, culturally or in religious rituals.

The relevance of the forest today lies both within its vast botanical wealth, and also its ability to ameliorate the environmental conditions that are steadily deteriorating due to the expanding population and increase of consumer lifestyles. However there is hardly any of this forest that remains free from human interference, the vast majority of forests in the area are little more than degraded thorny thickets, lacking the inherent nobility of the climax vegetation. It is the intention of this booklet to draw attention to the TDEF and put forward the case for its conservation.