Prelims Level
Mains Level
Prelims Syllabus : Biodiversity Mains Syllabus : GS 3: Conservation, environmental pollution and degradation, environmental impact assessment


  • There is a loss of grasslands in Western Ghats due to presence of exotic species.


  • Though grassland afforestation using pine, acacia and eucalyptus ceased in 1996, the exotics still invade these ecosystems.
  • Satellite images shows loss of grasslands in places such as Palani hills in Tamil Nadu Most of this loss occurred on the mountain tops of the Nilgiri, Palani and Anamalai hill ranges, which comprise more than half of the Ghat’s shola-grassland ecosystems, primarily due to the expansion of exotic trees (pine, acacia and eucalyptus)
  • Even though no plantations were established between 2003 and 2017, invasion by existing trees increased areas under exotic plantations by 27% in the Palanis and 17% in the Nilgiris.
  • Broadly, shola-grassland ecosystems in Tamil Nadu showed the highest rates of invasion. On the other side, shola forests have remained relatively unchanged over these years, giving a sense of relief. The Anamalai-Munnar areas have also remained stable during this time

About Shola forests:

  • Shola forests are tropical Montane forests found in the valleys separated by rolling grasslands only in the higher elevations. The shola forests are patches of forests that occur only in the valleys where there is least reach of the fog and mist. Other parts of the mountains are covered in grasslands. The trees never grow on the mountain tops. This is such a unique landscape formation that is native only to the southern Western Ghats. The Shola forests are generally said to be found in altitudes above 2000 metres of sea-level. Although they are found from altitudes higher than 1600 metres.
  • They are found only in the high-altitude mountains of the states Karnataka, Kerala and Tamil Nadu.
  • Nowhere else in the world exist such a kind of forests.
  • Due to high isolation and unique climatic conditions, the Shola forests are characterised by high endemism. The species of plants and animals found here are native to this region (this climatic region to be more specific) and such species cannot be found anywhere else in the world.
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