The impacts of social forestry on grasslands

The impacts of social forestry on grasslands

Western Ghats or the Sahyadri hills is a scenic holiday retreat for many. But, there is more to it. Being one of the eight 'world's hottest biodiversity hotspots', the natural ecosystem, including forests and grasslands, hosts an incredible number of plant and animal species and plays a significant role in maintaining the Indian monsoon. However, in the recent years, extensive human activities are threatening the survival of these lush green forests, and animal and plant numbers are dwindling. The famous and unique shola grasslands, which once dominated the mountains of the Western Ghats have now become one of the rarest habitats.

So what exactly is happening? To know this, a team of researchers and conservationists have used satellite images to study how, over a 40-year period, from 1973 2014, the grasslands, forests, plantations and agriculture lands have changed over space and time in Palani Hills, which range from Kerala to Tamil Nadu.

Sky islands

Shola grasslands get their name from the Tamil word solai, which translates to thick and cold forests. These grasslands, found in the higher elevations, are highly diverse and have 27 endemic species of grass; one of them classified as 'Near Threatened' by the International Union for Conservation of Nature (IUCN). Apart from being home to many animals, the grasslands channel water to low lying areas. Also, most of the South Indian rivers originate from this region, which in turn support millions of people who depend on agriculture downstream. Unfortunately, these grasslands have been considered as 'wastelands' for centuries. But in reality, they are termed as 'sky islands' since they are unique and isolated habitats found at such elevations.

"Sky islands are habitat islands - usually high elevation wet, cool habitats isolated by dry, warm low elevation areas," says
Dr V V Robin, an author of the study. In the Western Ghats-Sri Lanka region, a 'sky island' refers to the unique mosaic of shola forests and montane grasslands. Given the uniqueness, the 'sky islands' have been subjected to human interactions at various levels including tourism and agriculture resulting in deforestation and habitat loss. But out of all these interactions, the introduction of plantations into the grasslands in the name of social forestry has had considerable negative impacts on the ecology of the grasslands in the last few decades.

In the 1980s, timber and eucalyptus were planted in the Palani region of the Western Ghats for social forestry - a programme to manage and protect forests by afforestation of barren and deforested land to help environmental, social and rural development. It intended to cater the fuel and firewood supply to the rural communities in the area. But, in the later years, the plantations have proved to have severe impacts on the ecosystem, which in turn have adverse effects on the biodiversity of the Western Ghats.

"Although the Western Ghats are perhaps some of the better-documented landscapes in India, we still know little about insects and other vertebrates from this landscape," says Dr Milind Buyan, another author of the study. Until this study, there was no explicit quantification of the direct impact of such plantations on the ecology of the 'sky islands', and the shola grasslands.

In the study, published in the journal PLOS ONE, the researchers have used satellite images of the Palani Hills landscape of each decade from 1973 to 2014. Based on the different features of the landscape, they classified them into shola forest, shola grassland, timber plantations, human settlements, agriculture lands and waterbodies. They found that more than half of the landscape, 58% to be exact, had undergone a massive change over the 40-year period. It translates into a loss of 249 km2 of shola grasslands and 33km2 loss of the forest cover.

Among the factors affecting the survival of grasslands, the researchers point out that plantations, which had undergone a twelve-fold increase in the 40-year span, were the most detrimental to the native habitat. Land under agriculture, which increased from 31.1 km2 to 104.5 km2 in the same period, came second. They observed that the maximum change in the native vegetation occurred during 1993-2014 when the increase in plantation and agriculture was seen to be the highest.

Such an extensive change in the grassland habitats has left irreplaceable effects on the biodiversity of the shola forests. "We know that there are endemic birds in the landscape - one of the threatened endemic birds, Nilgiri pipit is restricted only to these montane grasslands, and their habitats are reducing, and may even face local extinction. We can only imagine that if this is the case with birds, that many plants, insects and other taxa are also impacted," explains Milind.

Conservation strategies

The researchers recommend a step-wise action plan to conserve the existing grasslands, starting from the identification and protection of core grasslands followed by looking for the invasion of plantations in grasslands that could still be saved and, controlling them. They also recommend having regulations for the removal of mature plantations since their removal could stimulate the regeneration of plantation species as their seeds could be dispersed in the surroundings. Finally, the researchers suggest involving the local community by starting community-led conservation efforts to control local agriculture in the grasslands.

Though this is not the first study to warn us of the threats the Western Ghats face, this is the first to explore in detail the fate of shola grasslands. The study also draws attention on how the generalisation of habitat types can lead to misrepresentation. So, how do we stop the damage? The researchers recommend a nuanced restoration model that involves various stakeholders like forest officials and locals, to restore and protect this unique habitat. "Conserving the remaining grasslands and preventing the advances of newer plantations into the grasslands in the landscape is the best chance to preserve and secure the future grasslands," they say.

With more studies addressing the specific effects of human activities on the natural environment, there is an increased awareness of the long-term impact of such actions. By impregnating the knowledge on the uniqueness and the importance of the shola grasslands to the public, the grasslands and the ecosystem of the Sahyadri forests could be conserved and preserved for the future generations, hope the researchers.

(The authors are with Gubbi Labs, a Bengaluru-based research collective)