|Biodiversity in the Western Ghats: An Information Kit (IIRR, 1994, 224 p.)|
|6. Plants, fungi and bacteria|
The concept of "plant association" is used in ecology in two ways:
· As a measure of similarity of occurrence of two species.
· As an assemblage of species comparable to a community. This is the meaning used in this sheet.
Plant associations can act as indicators of site quality. For example, the occurrence of Calmus pseudotenuis, Murraya paniculata and Ardisia solanea in primary forest indicates a very good soil. On the other hand, Calotropis gigantea, Trema orientalis and Lantana camara indicate poor soil.
Studies show that Goa, in the central Western Ghats, has lost 2% of its forest cover annually in the last thirty years. Of the original forest, 55% has disappeared through conversion to arable land, mining, human settlement or illicit clearing for fuel and timber.
Of an area of 3701 km², 55% of Goa is now non-forested; 42% constitutes dense primary forest, and 3% is secondary forest. Forest degradation is thought to be accelerating at the alarming rate of 2.4% per year.
Setbacks Mangrove, riverbank and sandy area associations should be protected by setbacks which limit land use for a certain distance from the mean high water mark.
Protected areas Representative samples of these ecosystems should be preserved in protected areas.
Land use zoning Land use activities which could have negative impacts on various plant associations should be sited accordingly.
Use of indigenous species Land use development should use indigenous spicies adapted to specific sites rather than introduced species. For example, sandy associations could use Ipornoea rather than Casuarina.
Human modifications of plant associations
· Development of hotels and other allied activities has led to the destruction of the sandy area association.
· Firewood collection in the rocky plateau association is resulting in laterization.
· Deliberate burning of grass results in the selection of fire-resistant varieties, which are often unpalatable and of low protein content.
· Humans have created various new associations, for instance in monocropped fields.
Major plant associations of Goa