Study shows that faunal diversity and density can’t attain original state even years after a forest fire

Scientists at the Kerala Forest Research Institute (KFRI), Peechi, have warned that recurring forest fire will lead to degradation of the ecosystem in forest areas, especially grasslands, of the State.

According to the data with the Forest and Wildlife Department, 1,056.72 ha of forestland had been devastated in 381 incidents of forest fire in the past four months.

“Since dried materials are needed as fuel, grasslands, scrub jungle, dry deciduous and moist deciduous forests are more susceptible to fire,” says K.A. Sreejith, scientist, Forest Ecology, KFRI, told The Hindu.

He says evergreen and shola forests generally escape the fire due to high moisture content in soil and absence of fuel load. But in the grasslands, the impact will be mainly on soil which gets degraded and mineralogical transformation may occur, which is irreversible. It decreases soil moisture and water holding capacity, that will have a negative impact on hydrology, Dr. Sreejith, who led a study, says.

He says fire creates open spaces in the grasslands and there will be an increase in soil nutrient content immediately, which will favour the growth of invasive species that will further degrades the system. The study indicates that the faunal diversity and density could not reach its original state even after a couple of years of a forest fire.

In natural conditions, when the fuel load is less, the fire will restrict as ground fire but additional fuel material, such as dry leaves, branches and fallen trees, may lead to surface fire.

Crown fire

In case of crown fire, the extreme stage of a disaster, fire extends to the crown of trees where complete loss of vegetation may happen. Crown fire generally happens when there is fuel load which can act as ladder up to tree canopy.

Forest fire will also make the system susceptible to exotic species, which is detrimental to the existing natural vegetation, T.K. Hrideek, scientist, KFRI, said.

When the diversity and density of vegetation go down, it will have a negative impact on all ecosystems services. This will lead to increased soil erosion, soil degradation, decreased water holding capacity, and ground water recharge, Dr. Hrideek added.