Restoring Montane Grasslands in the Palani Hills
The Vattaparai marsh might be missed as just another boggy wetlands bypassed on the way to the grander sights of the Palani Hills. Generations of students and hikers from KIS have passed its small watershed on the short cut to the Berijam road. In spite of its inconspicuousness Vattaparai is the site (see map below) of a groundbreaking study of Western Ghats montane grasslands hydrology and ecological restoration.
One of the major concerns about the loss of forests and native vegetation (including grasslands) in the Western Ghats due to aggressive afforestation programs is the dramatic impact on stream flow and hydrology. Healthy native forests in the mountains ensure a steady flow of water, a feature that is crucial in the leeward side of the Ghats where the eastern plains are arid and suffer from periodic drought. Evidence suggests that the introduction of fast-growing, non-native tree species has altered this flow of water. Plantations of trees such as Acacia mearnsii, Eucalyptus globulus and Pinus sp. provide wood but are also responsible for negatively affecting the water table. A study of two similar watersheds in the Nilgiri Hills adds credibility to this argument (see JS Samra’s 1998 paper). One of the strongest arguments for restoring native shola/grassland systems is to revive watersheds (an equally strong argument concerns the issue of biodiversity, something that I have addressed in other published work on this site).
The Vattakanal Conservation Trust, which has a long track record in shola restoration, started focusing on grasslands species about 10 years ago when the 2006 Kurinji blooming was being anticipated. Up to this point there had not been significant research on reviving and restoring montane grasslands in the Western Ghats and the Vattaparai project has been a pioneering effort. In 2009 Australian hydrologist Michelle Donnelly collaborated with the Tamil Nadu Forest Department and VCT to set up a landmark hydrological study of Vattapari. The task was to find a disturbed grassland watershed, record its key parameters (rainfall, water table height, stream flow, plant species, extent of grasslands etc.) and then monitor these as the area was restored. Vattapari provided an excellent site and the Forest Department’s support of VCT initiative helped put the project into action. Michelle’s report (as a Google doc) on the project documents all aspects and data of the project.
Water table monitoring wells and flow gauges were established in Vattaparai in 2009 and have been monitored since. In the meantime VCT with the support of the TN Forest Department and numerous volunteers has been working to restore the area around the marsh. This is a long-term study and it will take several years to see if the data supports the hypothesis that native grasslands provide a better watershed than non-native tree plantations. As might be expected there have been several challenges, notably in the gaur population that has trampled and broken tops of most of the ground water monitoring wells! Being herbivorous they also consume newly planted grass species before the plants can get established. In November 2010 a young male gaur was killed by Indian wild dogs (dhole) within view of a VCT team doing restoration work at Vattapari!
The pictures here were taken in April on a foray out with VCT to check the ground water monitoring wells and flow gauges at Vattaparai. The results and data coming in from the site will form an import body of evidence to pursue further high latitude grasslands restoration projects in the Nilgiri Hills, High Ranges and Anaimalais. For a more detailed discussion on ecological restoration in montane shola/grasslands systems in the Palani Hills see my Sanctuary Asia (2006) and Frontline (2012) articles.