Nearly 39 pc of Goa’s forest cover ‘highly’ vulnerable to fires: ICAR

PANAJI
As much as 38.90 per cent of Goa’s forest cover is “very highly” vulnerable to fires due to anthropogenic disturbances in the form of land use changes due to increasing demand for land parcels, conversions, infrastructure development among many others, reveals a vulnerability mapping study by ICAR-Central Coastal Agricultural Research Institute.

Assessment of forest fire occurrence in Goa revealed that over the last five-year period from 2017 till January 2023 an area of 521.29 ha was affected by fire, most of which was surface fire, with the largest area of around 220 ha affected during 2019-2020.

The study submitted to the State Forest Department, at the backdrop of a series of fire incidents reported in 2022, concludes that open and moderately dense forests are highly vulnerable to forest fires, with the distance from human settlement being the other crucial factor.

“Results indicate that a large area of 1077.7 sq km of forest cover in Goa is now very highly vulnerable to be followed by highly vulnerable 491.58 sq km and 543 sq km being moderately vulnerable. The maximum area estimated to be under the very high vulnerable class is 38.90% followed by moderate 19.64% and high 17.74% class. It is thus apparent that, large part of Goa’s forest cover is now very highly vulnerable to forest fires,” the study undertaken by scientists A R Uthappa, A Raizada, and Bappa Das, mentions.

“In the last decade anthropogenic disturbances in the form of land use changes due to increasing demand for land, land use conversion, infrastructure development, limited fodder availability, increasing cases of arson by vested interests at the village level and changing climate (increased dry periods, high rainfall in less number of rainy days, high diurnal temperatures) have contributed to an increased frequency of forest fire at various extents,” it said.

The ICAR-CCARI, Goa had submitted a proposal for undertaking a study on forest recurrence in Goa. The proposal was approved by the Research Advisory Committee (RAC) of the State Forest Department with the objectives – to identify the causal factors for forest fires in Goa, to map fire prone areas in forest through remote sensing and GIS and to suggest mitigation measures to manage forest fires.

The scientists studied the data on past fires to analyse criteria such as forest density, distances from human settlement, nearest road, elevation, slope, direction of the land, surface temperature, topographic wetness index, and average normalised difference vegetation index. They drew a susceptibility map using machine learning models.

The study said roads through forests made fires more likely, primarily on account of cigarette buds and roadside cooking by travellers. The absence of pre- or post-monsoon rains influenced factors like the topographic wetness index, land surface temperature, and the Normalised Difference Vegetation Index, a measure of the amount and health of green vegetation, also led to an increased susceptibility to forest fires.

“Forest areas at a distance of 1100 metres (1.1 km) from human settlement showed high susceptibility with the map indicating that the risk of fire was low close to human settlements, increased the further one went away from the settlement, peaked at 1100 metres and decreased thereafter,” the report stated.

The study found that south and west-facing lands that receive higher sunlight are more susceptible to fires. Forests at higher elevations are less susceptible. Lands with greater inclination are less vulnerable.

During the recent field assessment carried out at different sites, the experts noticed that litter quantities were in the range of 1.2 to 10.2 tons/ha in unburnt areas and 1.6 to 5.1 ton/ha in burnt areas, which was very dry and undecomposed due to the complete absence of moisture.

“It is these large quantities of forest debris which acts as fuel even for a small fire to spread rapidly,” the study added.

According to the researchers there is an urgent need to take adequate preventive measures as with infrastructure development taking place every year, more and more areas are exposed to human induced disturbances which correspondingly increases forest vulnerability to fire.

“While there is very limited control over changing climatic (rainfall, temperature and number of rainy days) patterns, a certain level of preparedness is required at the ground level, which is implementable and effective,” they said.

A large number of mitigation measures covering mechanical, biological, administrative, capacity building and legal strategies have been suggested which upon implementation, will lead to protection of forest areas from fire and also led to improved hydrological functioning and forest recovery in the areas.