Ian Lockwood

MUSINGS, TRIP ACCOUNTS AND IMAGES FROM SOUTH ASIA

Posts Tagged ‘mapping

Landcover Changes in the Palani Hills-A Spatial Study

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Lenny & Prasen on Dolphin’s Nose with Perumal peak in the far left. A panoramic composite image from January 2016.

The grasslands mapping project that took shape at the plantations conference in Kodaikanal in December 2014 produced a report that was published earlier this year. This is important work and represents the combined efforts of several disparate individuals, organizations and funding agencies. The preliminary visual assessment of Landsat imagery by the author showed that satellite data held spatial evidence of dramatic land cover change in the Western Ghats and Palani Hills but that it needed to be quantified. Robin Vijayan of ISER Tirupati put into motion a study in 2016 with key field work and spatial analysis being done by M. Arasumani and Danesh Khan. Further academic guidance was provided by Arundhati Das, Milind Bunyan and several others. Bob Stewart & Tanya Balcar, of the Vattakanal Conservation Trust, provided key insights on shola regeneration in plantations-the topic that originally brought everyone together. INTACH and ISER Tirupati helped provide funding of the field work. The Tamil Nadu Forest Department was an important stakeholder and helped provide permissions for the field work. Prasen Yadav joined the project to document the work and produce a video of the findings. The study was peer reviewed and published in January 2018.  It is publicly available on PLOS One, including access to all the tables of data and charts (see link below).

My involvement with the grasslands mapping brings together several interests and is the latest chapter in my ongoing interest and love affair with the Palani Hills. An alarming conclusion of the study is the great extent to which the montane grasslands have been taken over by non-native trees and weeds. Those of us who have been walking in the hills have had a sense of this but the satellite images providing damning proof. It is also clear that the plantations have spread far beyond the original boundaries that they were originally designed to be in. Most of the southern escarpment has a fire line etched into its grasslands and now plantations species are spreading beyond this boundary and down the steep slopes of montane grasslands. This leads to clear conclusion that where possible efforts need to be made to preserve these last remaining vestiges of montane grasslands. The challenge is that, in spite of the surprising resilience of shola tree species, the last montane grasslands are being steadily consumed by plantation (and some shola) species.

Our study concludes:

  1. Identify and conserve core grasslands: Core grassland areas consist of a few to many hectares of grassland encompassing hillocks, streams, marshes and rock outcrops. These areas, even when nestled in a plantation matrix, should be protected and form the core around which grassland restoration efforts should focus.
  2. Check invasion in sparsely invaded grasslands: These areas are often characterized by young plantations located in grasslands where grass cover is still extensive. Here, we recommend physical removal of invasive species. Forest departments often have access to significant funding through the Compensatory Afforestation (Bill passed in 2016) funds and these could be utilized for these activities. Such funds could be used for the restoration of marshes, existing grasslands and to manage the invasive plantations.
  3. Review indiscriminate removal of mature plantations: Mature plantations often have native shola forest regenerating under them and lack native grass cover. Grassland restoration here is likely to be very resource-intensive. Conservation efforts should focus on sparsely invaded and pristine grasslands. In mature plantations, we recommend conducting experimental or controlled studies (like at Vattavada, Munnar Kerala), perhaps also examining the role of fire, and monitoring soil and moisture conditions in these areas. Moreover, removal of mature plantations could stimulate regeneration of plantation species from saturated soil seed banks. Monitoring of these areas is important to assess the effectiveness of plantation removal.
  4. Contain agriculture: Our field surveys indicate that paddy cultivation has been discontinued in some marshes. Given the critical role of these marshes in regulating local hydrology, efforts should be made to contain agriculture to the current extent and restore these marshes using a community-led conservation effort.

Several other writes have reviewed the PLOS article in the popular press and I have listed articles in the Wire by Janaki Lenin, Mohan Rao in the Hindu and Pendharkar, Vrushal in Mongabay.

This year is a special year since it marks the cycle of Kurinji (Strobilanthes kunthianus) blooming that only happens every 12 years. Kurinji plants, more than any other grasslands species, are closely associated with healthy montane grassland systems. The extent of this year’s flowering will be a good gauge of the health of the grasslands of the Palani Hills.

My next personal chapter in this process to better understand the landscape and ecology of the Palani Hills is to present and share an exhibition of photographs and annotated maps at DakshinaChitra, Chennai this July. The next post will highlight this significant endeavor.

Southern escarpment on a very clear day looking west to the Agamalai range and beyond. January 2016.

REFERENCES & FURTHER READING

Arsumanoi, M. et al. “Not seeing the grass for the trees: Timber plantations and agriculture shrink tropical montane grassland by two-thirds over four decades in the Palani Hills, a Western Ghats Sky Island.  PLOS One. January 2018. Web.

Lenin, Janaki “You’d Think Cutting Kodai Plantations Will Save Its Grasslands. It Won’t.” The Wire. 19 September 2017. Web.

Lockwood, Ian. “Mapping Montane Grasslands in the Palani Hills.” Ian Lockwood Blog. August 2016. Web.

“         “Land Cover Changes in the Palani Hills: A Preliminary Visual Assessment.” Ian Lockwood Blog. 4 April 2014. Web.

Montanari, Shaena (& Prasenjeet Yadav). “Breathtaking Sky Islands Showcase Evolution in Action.” National Geographic. 11 August 2017. Web.

Pendharkar, Vrushal. “Palani Hills: Where have the grasslands gone?” Mongabay. 20 February 2018. Web.

Rao, Mohan. “Missing the grass for the trees in Western Ghats.” The Hindu. 17 January 2018. Web.

Yadav, Prasenjeet. “Save our Shola Grasslands.” YouTube. Web-Video. 16 September 2017.

Written by ianlockwood

2018-05-28 at 11:56 pm

Mapping Montane Grasslands in the Palani Hills

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Remnants of a pine tree that had invaded a patch of remote grasslands and then been ring-barked in 2013 as a part of an effort to protect the last vestiges of native montane grasslands in the remote Palani Hills. In the background the undulating hills leading back to Berijam and Kodaikanal have been thickly forested with non-native plantation species.

Remnants of a pine tree that had invaded a patch of remote grasslands and then been ring-barked in 2012 as a part of an effort to protect the last vestiges of native montane grasslands in the remote Palani Hills. In the background the undulating hills leading back to Berijam and Kodaikanal have been thickly forested with non-native plantation species.

Over the last year a group of scientists, conservationists, photographers and citizens have been working on a unique collaborative project to document and map the remaining grasslands of the Palani Hills. Montane grassland and shola habitats are a distinct feature of the upper Western Ghats and have been the focus of my personal explorations, writing and photography of/about  the area. The grasslands mapping project, supported by INTACH,  seeks to quantify the change in montane grasslands and draw attention to areas that can be restored. Robin Vijayan, now on faculty at the Indian Institute of Science Education and Research (IISERT,) in Tirupati is the coordinator. Other key stakeholders are associated with ATREE, NCBS and the Kodaikanal-based Vattakanal Conservation Trust. The Tamil Nadu Forest Department is a key partner and will be able to use the results to better plan restoration and management in the newly gazetted Kodaikanal Wildlife Sanctuary. Regular readers of this space will see that there are familiar themes highlighted in past posts, notably the post on the plantations symposium in December 2014 and the “preliminary visual assessment” post from April that year. This post highlights efforts of the group and a visit to the southern escarpment to ground truth areas that had been mapped with satellite data.

Inspecting a plot of cleared plantation on the road to Berijam Lake. The idea was to restore grasslands by clearing plantation. This has proven very difficult, if not impossible to achieve despite the best intentions. Cleared plantation areas soon become infested with weeds and wattle seedlings. In this image, pioneer Daphniphyllum neilgherrense trees are visible amongst the debris of the cleared wattle plantation. These pioneer shola species came up amongst the wattle that had been planted on grasslands. Thus, what emerges in plots that are located close to mother sholas is a hybrid plantation-shola mix in what was once montane grasslands. Examples like this illustrate the challenge and complexity of shola/grassland restoration in the southern Western Ghats.

Inspecting a plot of cleared plantation on the road to Berijam Lake. The idea was to restore grasslands by clearing plantation. This has proven very difficult, if not impossible to achieve despite the best intentions. Cleared plantation areas soon become infested with weeds and wattle seedlings. In this image, pioneer Daphniphyllum neilgherrense trees are visible amongst the debris of the cleared wattle plantation. These pioneer shola species came up amongst the wattle that had been planted on grasslands. Thus, what emerges in plots that are located close to mother sholas is a hybrid plantation-shola mix in what was once montane grasslands. Examples like this illustrate the challenge and complexity of shola/grassland restoration in the southern Western Ghats.

In July I had a chance to participate in a four-day survey of montane grasslands in the remote Palani Hills as part of the grasslands mapping project. For several months of this year the grasslands mapping project has employed two young and energetic GIS/RS technicians Arasu and Danish. They have been systematically classifying the Landsat data from 1973 and 2014 and then “ground truthing” land cover across the Palani Hills. The result has been a series of computer-based maps and data sets that show historical grassland compared to their current extent. It is an unprecedented enterprise in the Palanis and the results are startling. The data and maps will eventually be available for key stakeholders and the wider public once there has been a rigorous review process.

Danish and Arasu had ground truthed most of the upper Palanis Hills areas by June but the high plateau between Berijam and Vandaarvu was un-surveyed due to strict permissions regarding access to this core area of the sanctuary. It is an area that I have been visiting on and off since I was a student at Kodaikanal International School in the early 1980s –thus my role was to guide the group to some of the key places where there are still grasslands. We were joined by National Geographic explorer Prasenjeet Yadav who has been contributing his time and photographic talents to document the themes of the project.

The Berijam to Vandaravu area has experienced significant change as grasslands have been replaced with non-native plantations during the last 40 years. In the last two decades I have been more systematically documenting landscapes and key aspects of the ecology in the Palanis Hills and wider Western Ghats. Land cover changes are a particular interest brought about by personal experience (several generations of our family have explored the ranges). I have traditionally used a camera to document observations but increasingly I have been turning to remotely sensed images that can be used to monitor and measure land cover change.

Danesh taking data points at a rare grasslands patch on the way up to Ibex Peak. Behind stretches a view to Berijam and beyond-now all under thick forest cover.

From top left to bottom right: Danish taking data points at a rare grasslands patch on the way up to Ibex Peak. Behind stretches a view to Manavanur and beyond-now all under thick forest cover. Close up views of Mapit logging attributes and getting a GPS point.

From top left to bottom right: Cutting through fallen pine trees on the road to Katrikodai from Berijam. Prasen inspecting steep slopes and remnant grasslands at Prayer Point near Marion Shola. Danesh with forest guards logging a point on Mapit.

From top right to bottom left: Cutting through fallen pine trees on the road to Katrikodai from Berijam. Prasen inspecting steep slopes and remnant grasslands at Prayer Point near Marion Shola. Danish with forest guards logging a point on Mapit.

The visit to Kathcikiriodai and Ibex Peak in July gave our small party a good sense of how little natural grasslands are left in the Palani Hills while also appreciating the complexities that the plantation ecology have brought about. Initially we were delayed by fallen pine trees on the road (the old Kodai-Cochin road) and our team had to spend the night at the Berijam FD bungalow. On the second day Bob & Tanya drove us up to the road blocks and then we trekked into Kathcikiriodai. On our walk to Kathcikiriodai it occurred to me that there are only two types of grasslands surviving in this area: marsh grasslands and patches of non-native grasses growing on areas that used to be coop camps for woodcutters (when the area was actively logged). Otherwise everything else is plantation with virtually no shola (Marion Shola has a healthy shola and there must be a few others away from the road).

Grassy patch of non native grass species in an area that was once a coop shed where Sri Lankan repatriates worked to plant and harvest non-native timber species. I have memories of walking by remote, squalid camps in the 1980s during our hiking program.

Patch of non-native grass species in an area that was once a coop shed where Sri Lankan repatriates lived while working to plant and harvest timber species. I have memories of walking by remote, squalid camps in the 1980s during our school’s hiking program.

Forest guards taking out a young pine tree invading cliff side grasslands near Ibex Peak.

On the afternoon of Day 2 we visited Marion Shola, its dilapidated bungalow and the nearby cliffs. There had been a fire on the cliff edge-formerly grasslands abut now invaded with mostly eucalyptus. We revisited the site on the last day and were able to get a much better sense of the habitat, land use and awesome cliffs. We spotted a small herd of Nilgiri tahr (in close proximity to a bonnet macaque troop) several hundred meters below us. We appreciated the significant montane grasslands that crown the Agamalai range to the south – not in our study as they fall in the Theni district.

We had our most significant day on Tuesday July 19th when we trekked with four forest guards out to the Ibex Peak cliffs. We were blessed with sunshine and clear weather for the first crucial hours of the trip. On the way we passed though a few native grasslands patches as well as areas where grasses coexisted under thin eucalyptus plantation (Danish mapped and photographed all of these). I was alarmed at the cliff edge where it seems to me the wattle and pine is making advances into the strip of 30m or so grasslands that was never originally planted. The 2013 restoration efforts were visible (dead, leafless pine, and trunks with rings). However, as Bob Stewart later reiterated, it can not be a single effort and more, regular work needs to be done if these last grasslands are going to be saved. We walked up to Ibex Peak (2, 517 m), explored the marsh below it, which is still in very good shape and then headed back to Kathcikiriodai a little after noon. By that time the whole cliff area was covered in mist.

Scenes of grasslands on the path to Ibex Peak showing varying levels of invasion by non-native timber plantations.

Scenes of grasslands on the path to Ibex Peak showing varying levels of invasion by non-native timber species.

Interestingly, we heard some of the key shola species as we walked through the plantations-White Bellied Blue Robin (Myiomela albiventris), Black and Orange Flycatcher (Ficedula nigrorufa), Nilgiri Wood Pigeon (Columba elphinstonii) and Kerala Laughing Thrush (Trochalopteron or Strophocincla fairbanki). There was a pair of Nilgiri pipits (Anthus nilghiriensis) at Kathcikiriodai -apparently content amongst the non-native grasses and remnant marsh habitat. We photographed two different shrub frogs, found a Salea sp. (most likely anamallayana) in the burnt out eucalyptus and came across a shieldtail on the walk out (near one of the coop patches). The only gaur we saw was a herd from near Ibex Peak. There was significant elephant dropping evidence along the roads.

The four forest guards provided important support to our group and I gained a new appreciation for their role. Two accompanied us from Berijam and another two were based at Kathcikiriodai. They are clued into restoration and removed pine saplings from our path to Ibex Peak (at least one of them had worked with VCT on the cliff restoration initiative four years ago). They are however not well supported and have minimal equipment. They had no working wireless and with no cell phone connectivity and they are completely on their own! After trekking with forest guards and staff in other PAs in south India I feel that much more could be done for these men and their important work.

At the escarpment edge just east of Ibex Peak, the 2nd highest peak in the Palani Hills. These are the crucial grasslands that have been identified to be saved from encroaching invasive species. Our survey found them still intact but under pressure as pine, wattle and even eucalyptus spread beyond their original plantation boundaries.

At the escarpment edge just east of Ibex Peak, the 2nd highest peak in the Palani Hills. These are the crucial grasslands that have been identified to be saved from encroaching invasive species. Our survey found them still intact but under pressure as pine, wattle and even eucalyptus spread beyond their original plantation boundaries.

We made several important observations over the course of our survey:

  • Almost all the plateau’s montane grasslands area from Berijam to Vandaravu was planted with non-native timber plantations species in the last 40 years. This is supported by satellite evidence and terrestrial photographs from the 1960s and 70s. There are virtually no unplanted grasslands areas unless they contained shola or the soil was too thin.
  • There are several small grasslands patches on the road to Kathcikiriodai and Marion Shola. Remembering experiences from my school hiking days I am reminded that these are former coop shed camps that housed labor (often Sri Lankan repatriates) planting and harvesting timber. The patches do not support native grasslands but appear to provide fodder for herbivores (gaur, sambar).
  • Several large and medium-sized marshes in the area were left unplanted (for obvious reasons). These still exist, though there is some invasions of pine. One large marsh (10.168704° N, 77.366623°E) was dammed to provide drinking water (Konalar dam) for Poondi and Kavanji villages. Its lake now extends all the way to what used to be known as First Trout’s Stream.
  • Shola regeneration in the plantations between Berijam and Kathcikiriodai is extremely limited other than the beginning where plantations adjoin the Temple Shola near the Berijam FD camp. It illustrates the apparent fact that without a “mother shola” there is limited spread into plantations.
  • Plantations appear to have been planted to approximately 30 meters of the escarpment edge (a very abrupt border). These edges once supported remnant montane grasslands and were important for Nilgiri tahr and other herbivore populations. However, most of these edges have now been invaded by plantation species. The Ibex Peak cliff to Ullam Pari grasslands are some of the last remaining patches but these are experiencing invasion (see photos).
  • The May 2012 restoration work by VCT arrested some of this invasion in a limited area. However, it needs to be a regular intervention if these critical grasslands are to be saved from being overtaken by plantation trees.

In conclusion, I want to put in a special word of thanks to VCT for organizing the permissions and the drop off and pick up. My colleagues Prasen and Danish were excellent company. We are grateful to the TN Forest Department for facilitating the survey and providing us with the guards and accommodation at Kathcikiriodai. I am looking forward to making further contributions to the project and effort to protect this part of the Western Ghats.

The maps that are referred to earlier, as well as my own tinkering with spatial data, will be shared in a future post.

 

PAST BLOG POSTS & PUBLICATIONS

Lockwood, Ian. “Recent Publications.” Ian Lockwood Blog. 11 November 2015. Web.

“         “Forest Plantations and Biodiversity Conservation: A Symposium in the Palani Hills.” Ian Lockwood Blog. December 2014. Web.

“         “Land Cover Changes in the Palani Hills: A Preliminary Visual Assessment.” Ian Lockwood Blog. 4 April 2014. Web.

“         “Landscape and ecology in India’s Western Ghats: A Personal Odyssey.” Asian Geographic. July 2008. Print & Web.

“         “Restoring Montane Grasslands in the Palani Hills. Ian Lockwood Blog. July 2012. Web.

“         “On the southern rim of the Palani Hills (Part II). Ian Lockwood Blog. September 2011. Web.

“         “On the southern rim of the Palani Hills (Part 1). Ian Lockwood Blog. September 2011. Web.

Written by ianlockwood

2016-08-22 at 11:56 pm