I’ve made a pact with myself that I will write a plain language summary for each paper I publish as the first author, to make my work more accessible for people beyond the ivory tower. Some journals, e.g. People and Nature, now encourage this for each of their publications. Whether you believe or not that scientists have a role in advocacy, I believe that sharing the treasure of knowledge with the people that funded our adventure is our responsibility. And perhaps it’s better to tell the story with scientific facts, than ‘facts’ derived through alternative means? Here is my first attempt at an accessible summary for my last publication. (Though it’s still too sciency, a good friend pointed out – I’ll try for properly plain next time! All comments welcome!)
Over the past year, it’s been rare to pass a day without hearing of forests burning, whether in Australia, Brazil or Siberia. The frequency and intensity of forest fires seem to be increasing, with devastating impacts on people and nature. But fires in forests are not a new phenomenon and can be vital to the resilience of these ecosystems. Historical and palaeoecological work can provide context from which to compare these contemporary fires and provide evidence to demonstrate the impact of management and policy.
One type of forest that has gained a global reputation in recent decades for its spectacular fires is degraded tropical peat swamp forest. In an intact state, these waterlogged ecosystems accumulate carbon under their prevailing anaerobic conditions, making them hugely important for mitigating the effects of rising GHG emissions. But are fires unique to degraded tropical peatlands or do intact peatlands burn too?
Our recent paper* answered this question for three peatland sites along the coast of northern Borneo, within the Malaysian state of Sarawak. We collected a set of peat cores from each site and spent many hours in front of the microscope gathering data on elements of the landscape over the last 7,000 years. Fossil pollen grains were identified to provide knowledge on the floral components of the landscape over time and distinguish major ecosystem types. Fossil charcoal particles were counted to reconstruct past fire regimes in these swamps, including incidences of forest burning that were above the background levels. We also looked at a wide range of historical and contemporary literature to explore the interactions that people have had with these peatlands over the last 500 years: the approximate time of people’s arrival in the flooded coastal forests, the changes in land titling and the political pressures on land management in recent millennia.
Our results demonstrate that intact tropical peatlands do burn. They probably burnt more in years when the El Niño Southern Oscillation (ENSO) – a climatic phenomenon that brings drier, warmer weather to this region in irregular, sub-decadal intervals – was stronger, but the peat swamp forest seemed to recover even from these more intense fires. However, cue people’s entry into the story, c. 1850s, and the narrative changes. Fossil charcoal levels reach unprecedented levels, in parallel with indicators of deforestation. And the peat swamp forest shows signs of losing its long-standing stability – the ecosystem’s resilience appears to be compromised by the simultaneous forces of fire and deforestation.
Many of the forests standing in the Anthropocene have been degraded. Their resilience has been compromised by unusually low precipitation (resulting from regional climatic drying) or by management interventions that disrupt natural disturbance regimes, or by both, pushing them beyond the limits of their ecological memory. Our work suggests that tropical peatlands have recovered from episodes of burning throughout the Holocene. But the presence of people, agriculture and fire in peatlands seems to be a recipe for disaster. There is no shortage of contemporary literature and news reports supporting the notion that a drained peatland burns. Our work contributes to the common narrative that for climate change mitigation and for the universal long-term benefit of people and nature, drainage and deforestation are not compatible with sustainable management of tropical peatlands.
*Cole, L.E.S., Bhagwat, S.A., and Willis, K.J. (2019) Fire in the Swamp Forest: Palaeoecological Insights Into Natural and Human-Induced Burning in Intact Tropical Peatlands. Frontiers in Forests and Global Change. https://doi.org/10.3389/ffgc.2019.00048