PAs in Western Ghats slow down deforestation except near highly populated areas, finds study

A patch of  agricultural field bordering forest land in Southern Western Ghats in Kerala.
(Image Credit: Indian Biodiversity Talks)

A new study about forest cover loss shows that protected areas (PAs) in Western Ghats were able to slow down the rate of deforestation. However, in areas with high population density, deforestation rates are higher even in the PAs. 

Published in the Biological Conservation journal, the study shows that the forest loss inside protect areas was 32 percent less than that in other areas. However, the scenario is different in case of PAs near dense human populations where there is a higher possibility of losing the forest cover. “Where local human populations were higher in the Western Ghats, protected areas were 70% more likely to lose forest cover than non-protected areas”, says the study.

Analyzing a data set of satellite images of Western Ghats between 2000 and 2016, the study estimates that there was a net loss of 750 square kilometers of forest cover in Western Ghats during the 16 year period. This is slightly higher than the previous estimates. 

The absolute forest loss was higher in evergreen forests while the proportion of the forest loss compared to total forest area was more in dry deciduous forests. “We found that evergreen forests showed the highest net absolute losses, but loss rates as a proportion of forest area was highest among dry deciduous forest.”, said Meghna Krishnadas, a researcher with the School of Forestry and Environmental Studies at the Yale University  who was part of the study. 

The study also confirms the impact of roads on forest cover loss in Western Ghats, a tropical biodiversity hotspot. According to the study, there was a 16 percent increase in forest cover loss for every 4 km closer to roads. Forest cover loss due to proximity to roads was 32 percent lesser in protected areas than in non-protected areas.

According to the researchers, properly distinguishing between actual forests and plantations with natural tree canopies was a major challenge. “We tried to overcome this limitation to some extent by using land-cover data that classified 1 x 1-km areas into different land-use types. Using this land-cover data, we only chose areas that were classified as forest. This is of course not fool-proof, but we hope that this step removed areas that are known to be plantations and monocultures. However, the best way to do this would be ground-truth points but this is often infeasible for large landscape studies,” says Meghna.

The researchers believable that the findings would also help in making better policy decisions about conserving Western Ghats. “At a broad scale, this would help to identify areas which are likely to be more vulnerable to future [forest] losses,” Meghna said.

Meghna Agarwala from Earth Institute Center for Environmental Sustainability, Columbia University, Sachin Sridhara from College of Marine and Environmental Science, James Cook University and Erin Eastwoodd, Center for International Forestry Research, Indonesia were also part of the study.