BENGALURU: Recent research has revealed that the highest number of forest fires occur in the mid-rainfall region and not in the driest regions of the forest as one thought of. This study was carried out by researchers of Indian Institute of Science in the Mudumalai Wildlife Sanctuary and National Park, Tamil Nadu.
The study was carried out across the entire sanctuary over a 20-year period (1990-2010) by collating and analysing records of forest fires and also supplementing this by data from satellite imagery. Field records of fires has been kept by a small team of researchers over the years. This study was conducted by Nandita Mondal, Ph D student under the guidance of Prof Raman Sukumar, Centre for Ecological Sciences, IISc.
Speaking to Express, Prof Sukumar said,“Studies revealed fires were most frequent in the medium rainfall region rather than in the driest or the wettest region. In the dry regions, fires are limited by the amount of fuel available because of low productivity of vegetation (fuel here refers to leaf litter, grasses and other ground vegetation). In the wettest region, there is a lot of fuel available to burn but it is usually too wet to burn. Thus, the medium rainfall regions provide the ideal conditions for more frequent ground fires to occur.”
Mudumalai encompasses a range of vegetation, depending upon the rainfall regime. It is seasonally a dry tropical forest with a defined dry season. This makes the forests susceptible to fire almost every year. However, regions within the forests with different vegetation types are affected by fire to different extents.
This study also investigated the different environmental constraints that influence the spread of fire in different regions within Mudumalai. The researchers divided the study area into four moisture regimes in the order of decreasing annual rainfall.
Prediction of Fires
“We can now predict the risk of fire occurring on a given day during the dry months. If automatic weather stations are set up in forest areas and data generated on a daily basis. This can help the forest staff responsible for combating fires to be more alert on those days,” said Prof Raman Sukumar, IISc. “Fire can be used judiciously as a tool in preventing destructive fires by managers through early dry season burning to reduce fuel loads. This approach calls for a lot of R&D before made operational,” adds Sukumar.
With the aim to understand the interplay of forest fires and biodiversity, the researchers will next determine the sensitivity of different plant species to fire. The insights from such studies can be used to control destructive fires and also use fire as a management tool at the appropriate season for maintaining biodiversity.