Posts Tagged ‘Anaimalai Hills’
Land Cover Changes in the Palani Hills: A Preliminary Visual Assessment
1973 Landsat map of the High Range, Anaimalai and Palani Hills. (February 1973)
41 years later….Landsat view of the same area (February 2014)
I continue to be interested in themes of change in the southern Western Ghats (and Sri Lanka) and am now working to better measure and detect land cover change using Geographic Information Systems (GIS) and temporal satellite data gathered by the USGS/NASA Landsat satellites. My interest in the area has grown out of a deeply personal engagement with the landscape over the last few decades. It started on childhood walks with my parents, was excited by explorations with friends in school and then developed in more systematic photo-documentation trips as an adult. In recent years teaching and family commitments have kept me from visiting the field as much as I would like. My interest in using GIS as a tool for teaching and learning has brought me back in touch with the Western Ghats, but this time through the lenses and sensors of distant earth observing satellites. In the last year I have been working with the latest Landsat 8 imagery and am thoroughly impressed with the quality of the imagery that is now publically available. This has led me to look back through NASA’S archives to find old imagery to conduct change detection with. This post highlights preliminary comparison of Landsat mages from 1973 and 2014.
The maps included in this post look at the block of the southern Western Ghats just below the Palghat gap where significant features illustrate momentous changes in the landscape over the last forty years. Both sets of images were collected in February, a time of the year when it is dry and there are cloud free days in the southern Western Ghats. The first image, however, was taken 42 years before the 2nd and thus offers a unique opportunity to compare the land cover changes in these hill areas. My particular interest here is the western plateau of the Palani Hills. This is an area that many generations of KIS students know well from the hiking program that took us to places like Vembadi Peak, Berijam Lake, Vandarvu and the Ibex Cliff area. Starting in the 1960s and 70s these areas experienced intensive silviculture based on the earlier designation of montane grasslands being “wastelands.” Few KIS students and faculty members appreciated that they were witness to a radical ecological reworking of the landscape. The net result has been a significant change in the ecology and landscape of the area. Vast areas of the shola/grasslands systems in the Vembadi-Berijam-Vandaravu area have experienced significant changes.
It is a complicated mosaic of vegetation, ecosystems and issues that is now in place on the upper plateau of the Palani Hills. As the 2014 Landsat 8 image illustrates, most of the Vembadi-Berijam-Vandaravu area is covered by non-native tree plantations but there are important sholas that thrive between them. Several invasive species are spreading beyond plantation boundaries and threaten the remnant grasslands. In some areas shola species are regenerating in and amongst non-native plantation species. Some feel that this will eventually give way to mixed forests of shola species and dying plantations. Logging of planation species has been largely curtailed though there is a move afoot in the Forest Department to remove exotic species. Much of the upper plateau area is of limits because of forestry rules that have sought to limit the impact of tourists and agricultural communities in the reserve forest (RS) zone. A Kodaikanal National Park is in the pipeline and its notification and boundary lines are expected in the near future. Nevertheless, human communities are pushing into outer areas as the township of Kodaikanal and its satellite communities expand. Gaur (Bos gaurus) populations are on the rise, felt mostly in urban areas rather than remote areas!
Looking south over the 2,000 meter high Eravikulam plateau from Kattu Malai. The sunrise highlights the extensive “downs” of the shola/grasslands complex that is uniquely preserved in this magical National Park. Anai Mudi’s distinctive hat profile is on the right horizon while the edges of the Palalni Hills are on the far left. My father Merrick and cousin Anna are at the edge taking in an unforgettable Western Ghats experience.
One feature that has remained relatively constant has been the shola/grasslands mosaic that makes up Kerala’s Eravikulam National Park and Tamil Nadu’s Grasshills (part of the Anaimalais Tiger Reserve). Comparing both the 1973 and 2014 maps shows that these areas of montane grasslands, interspersed with sholas, have stayed roughly the same. This perhaps is no accident since Eravikulam and Grasshills have both enjoyed protection in the midst of the flurry of tree planting in the adjoining ranges. The grasslands show up particularly well and contrast with the neighboring shola vegetation. This is most likely the result of winter frost that has dried out much of the exposed grass (and thus is not photosynthesizing).
Eravikulam will feature in a series of upcoming posts tentatively entitled the High Range Diaries but I have included a few images from my visits and explorations of the area in the 1990s.
View of Anai-Mudi & the Eravikulam plateau from the east. Note how the lowland tropical rainforest has been cut back to make room for tea estates. Anai-Mudi is on the left and the sheer granite cliffs that protect the park are obvious. These same cliffs provide a home for the most secure population of Nilgiri tahr. This was taken with my friend Rahul Madura on an Enfield tour of the area. Scanned from two 35mm color negatives. (December 1994)
Pine plantation in the Palani Hills near to Poondi.
The classic tourist view: looking west over Berijam Lake from the fire tower view point. In this image, the arm of Mathikettan Shola is clearly distinguishable from the uniform, tall eucalyptus plantation (extreme left and right). These trees were planted on montane grasslands in the 1960s and 70s in a program to increase biomass for fuel and tanning purposes. With the existing Landsat imagery it is difficult to distinguish shola patches from such evergreen plantations. This makes accurate classification at this sale challenging. In the future, as the resolution of the satellite imagery improves, remotely sensed multi-spectral imagery should be able to make this distinction.
Index map for hill ranges of the southern Western Ghats using recent Landsat 8 multi spectral imagery.
FURTHER REFERENCES
Be sure to read Farshid Ahrestani’s article “To cut or not to cut” published by Conservation India last month. It looks at the dilemma of what to do with the huge amount of non-native tree plantation biomass in the Palanis and other Western Ghats ranges. We visited Eravikulam together, through the good offices of KN Chengappa and Tata Tea, in 1993 and continue to share a passion for conservation issues in the Palanis and neighboring ranges. One of ours tasks is to collect historical imagery of the hill ranges and use these to cross reference with contemporary imagery to illustrate change at a terrestrial level (as is done in his article).
For information about interpreting false color satellite imagery, see Hollis Riebeek’s excellent article on the Earth Observatory website.
SCHOLARLY (and TECHNICAL) ARTICLES
Amaranth, Giriraj et. al. “Diagnostic analysis of conservation zones using remote sensing and GIS techniques in wet evergreen forests of the Western Ghats – An ecological hotspot, Tamil Nadu, India.” Biodiversity and Conservation. 12. 2331-1359, 2003. Print.
Joshi, Kumar P.K. “Vegetation cover mapping in India using multi-temporal IRS Wide Field Sensor (WiFS) data.” Remote Sensing of Environment. Volume 103 Issue 2. 30 July 2006. Web.2 April 2014.
Menon, Shally and Kamal Bawa. “Applications of Geographic Information Systems, Remote-Sensing, and a Landscape Ecology Approach to Biodiversity Conservation in the Western Ghats. Current Science. 73.2 (1997): 134-145. Web. 30 March 2014.
Nagendra, Harini and Ghate Utkarsh. “ Landscape ecological planning through a multi-scale characterization of patterns: Studies in the Western Ghats, South India. Environmental Monitoring and Assessment. 2003. Web. 30 March 2014.
Nagi, Rajinder. “Using the Landsat image services to study land cover change over time.” ARCGIS Resources. 13 May 2011. Web.
Prakasam, C. “Land use and land cover change detection through remote sensing approach: A case study of Kodaikanal taluk, Tamil Nadu.” International Journal of Geomatics and Geosciences. Vol 1, No 2, 2010. Web. 30 March 2014.
Restoration & Revival in the Anamalais
We had a very satisfying encounter with a troop of Lion Tailed Macaques (Macaca silenus) that was in the process of raiding the Puthuthottam Estate hospital. I was able to follow them into a patch of mixed plantation and natural vegetation forest to take the pictures in this post.
(PART II IN A SERIES OF THREE)
The South West was in full force when Lenny and I drove to the Anamalais from Kodai via Palani and Udumalpet. We had hired the good services of AP John and his small Indica for the three-day rip. The Anamalais Tiger Reserve (ATR) is a large and expansive protected area though it is interrupted by large patches of human settlements and modified landscapes. Most people looking for wildlife will head to Topslip, which is south-west of Pollachi. The Valparai area has traditionally attracted fewer people and for good reason. The accommodation options are limited and the area is dominated by large monoculture estates of tea. Access into the forests and high Grasshills area of ATR is strictly restricted and is not a viable option without significant bureaucratic gymnastics in Chennai and Pollachi.
- Clearing showers over the Aliyar reservoir looking east into the Anaimalai Hillss.
The ride up to Valparai is worth the trip in itself. The ghat road up from Udumalpet via the Aliyar reservoir has an incredible 40 hairpin bends (the Battlagundu-Kodaikanal ghat only has one for comparison’s sake)! The road winds its way up a steep ascent with dry deciduous and thorn forest that quickly changes into moist-deciduous and then evergreen rainforest in the space of 10-20 kilometers.
View looking north from hairpin Bend #9/40 on the Pollachi-Valparai road. At times this is a good location to see Nilgiri tahr.
One of the most promising conservation projects in the Western Ghats is based out of Valparai where the Nature Conservation Foundation is working with several tea estates to restore degraded rainforest patches. The issue is close to my heart and something that I continue to learn and teach about. I’ve worked with the Vattakanal Conservation Trust to highlight their restoration work in shola/grasslands habitats changed by the widespread introduction of non-native tree species in the Palani and Nilgiri Hills. My 2005 article in Sanctuary entitled (by the editors) “the next big thing” described their work and the challenges of restoration in such sensitive habitats. In the article I mentioned the NCF work in the Anaimalais and have wanted to see it in person since.
- Lenny outside and inside of the Anaimalai Nature Information Centre (ANIC).
NCF, of course, does a good deal more than ecological restoration and they have research projects in the Western Ghats, North-East and Andaman, Nicobar and Lakshadweep Islands. Before going over to the Anamalais I contacted Shankar ‘Sridhar’ Raman and Divya Mudappa to set up a time to visit the NCF interpretation center. They were away but were able too hook me up with other NCF team members in Valparai. I first remember meeting Sridhar in Sengeltheri, (KMTR) in 1997 when he was conducting his dissertation study of birds in tropical rainforests of the Southern Western Ghats. I was on a short visit and was enjoying fine pre-monsoon weather to document different scenes including the view that led to the “Kalakad tree” image. Karthikeyan Vasudevan, of the Wildlife Institute of India, was also staying in the same hut conducting his research on amphibians. I remember being thoroughly impressed with their set up, passion for their work and individual studies.
Along the road to Valparai NCF runs what must be the most effective and informative interpretation centers in the entire Western Ghats. The Anamalai Nature Information Centre (ANIC) was our first stop on the Valparai plateau and Lenny and I were warmly welcomed. The location is a small bungalow immediately next to the main Valparai road in the Iyerpadi area. There are rooms dedicated to different habitats, species and challenges in the Western Ghats. A large number of attractively designed posters with beautiful digital pictures, write-ups and paintings by Maya Ramaswamy helps the viewer get a real sense for the range. They also have several publications for kids and adults and we left with lots of materials for the kids and school. I was happy to pick up an extra copy of Whitaker and Captain’s Snakes of India to replace the one that I had given to my Dhonavur friends. Our first point of contact at NCF was P. Jeganathan later Ananda Kumar talked to me about the plant nurseries. Jegan set us up to find the LTMs at the Puthuthottam estate utilizing the sharp skills of their watcher Joseph. Later that day he took us on a tour of the NCF nursery and interesting points near Valparai.
- Satish, one of NCF’s Valparai team members, shows off a three-year old Cullenia excelsa sapling that he is getting ready to transfer from the nursery to a degraded forest patch in the a nearby estate.
The NCF nursery was wet and misty on both days that I visited. Tata Tea has given them a section of one of their own tea nurseries to nurture rainforest trees that are collected from seeds on roadsides in forest fragments. These are documented, germinated and grown for the next 2-3 years. Once fragments are identified in tea-estate forests, sapling are taken from the nursery and planted during the monsoon season. The forest structure and conditions are carefully considered when choosing species to plant. Grazing has to be curtailed and invasive species removed when possible. Local communities, play a key role in education outreach and efforts to reduce collection of rainforest trees for firewood. A good deal of science and research goes into it and my observations were fleeting. Nevertheless, I came away impressed and hopeful in these small efforts to redress ecological ruin.
Lion Tailed Macaques (Macaca silenus) in mixed (plantation+ natural) forest near the Puthuthottam Estate hospital.
