JOIN USControlled fire as a management strategy in agroforestry landscapes
Using controlled fire on farmland does not necessarily have a destructive effect on biodiversity, says a new study conducted by ecologists and geographers on an ancient agroforestry system in Karnataka.
The study was conducted because the researchers sought to gauge the impact human-made fires have on ecosystems, particularly where the use of fire causes conflict between land managers and state authorities, according to Dr Charuta Kulkarni, European Union Marie Curie Fellow based at The Open University, UK, and the lead author of the study.
“Using the wet evergreen forests of the Western Ghats as a model system, we examined the synergistic effects of human-made fires and enhanced aridity on the tropical plant diversity over the past 4,000 years,” Kulkarni said.
She added that the research included an examination of historical data from the Western Ghats, including fossil pollen-based diversity, past fire management, periods of reduced monsoonal rainfall, and the history of land use in the study region: Kodagu.
Clearing landscapes
The researchers examined past fires by cataloguing fossilised remnants of charcoal trapped in sediments, to determine in what context people used fire to clear landscapes for farming, grazing, or establishing settlements.
“The long-term charcoal record from the agroforestry landscapes in Kodagu obtained in this study informs us that fires have been part of people’s land management strategies as far back in time as 3rd Century AD, closely linked with the extensive establishment of settled agriculture in the region,” Kulkarni said. She added that fire management, thus, is a component of local knowledge that still echoes in small-scale agriculture as well as in the practices such as shifting cultivation by indigenous communities living along the fringes of forests of the Western Ghats and many other ecosystems across India.
While the researchers acknowledge that fire practices were suppressed during the colonial era by the British who could not conceive of fire having use in forest areas, the Indian Forest Service has continued to pursue a policy of “laboriously preventing fires” when in fact agroforestry systems are sustained through careful management of fire.
“Fires can cause some damage to the aesthetics of a landscape, but we are not talking about extensive summer blazes. Typical agricultural landholdings are much smaller in the humid tropical forests of the Western Ghats. It makes sense for these smallholders to make use of controlled fire as a land management tool because their livelihoods are dependent on it,” Kulkarni said.
Shaped by fires
It is an assessment that Dr Raman Sukumar, Professor Emeritus, Centre for Ecological Sciences at the Indian Institute of Science, Bengaluru who helped design the Nilgiri Biosphere Reserve, agrees with.
“If a forest has not been touched by fires over a period of years, it goes back to having a high degree of moisture content and it will be hard to burn, but the evidence shows that these kinds of forests are rare. Most forests worldwide have been shaped by fires, either man-made or through lightning strikes. Forest management is required to avoid a more destructive fire event,” Dr Sukumar, who was speaking as an independent expert, said.
He added that there are lessons to be learned from indigenous communities using small-scale controlled fires to burn off biomass, which when left untended for several years can build up large volumes of biomass and lead to large infernos.
As per existing data, over 80% of Indian farmers are small landholders, owning less than two hectares. They are reliant on monsoon rains for irrigation. Such farms are under stress because of the absence of assured irrigation. Agroforestry is seen as a solution for them to increase moisture retention under the tree cover and meet the challenges of food, nutrition, energy, employment and environmental security.
“By developing a historical perspective, our aim was to provide region-specific management information for biodiversity conservation in the Western Ghats, because our systems today are not ‘ecological’ alone, rather they have become intricately social-ecological, making their management yet more complicated,” Kulkarni said, adding that the damage caused by agricultural intensification means that agroforestry practices need to be adopted on a larger scale if India is to meet the future challenges of feeding its people whilst also protecting its biodiversity.
She added that, in this context, India’s National Agroforestry Policy is “enchanting in a way that it would basically make jobs and livelihoods available while maintaining forest cover and biodiversity in our landscapes. It is a win-win nature-based solution for fulfilling both social and ecological challenges.” The study is published in the Journal of Environmental Management.