Climate Change, Fire and Forest Resilience

Multiple SDGs hinge upon tropical forests. To ensure sufficient food and nutrition for all, we must achieve nature-positive production landscapes through both sustainable agriculture and natural forest conservation. Forests continue to be central to mitigation and adaptation responses to climate change, as well as to the conservation of biological and cultural diversity. Reports from the Intergovernmental Panel on Climate Change (IPCC), the Scientific Group of the UN Food Systems Summit, and the Intergovernmental Panel on Biodiversity and Ecosystem Services (IPBES) support these key points for sustainability but also conclude huge uncertainty associated with forest conservation. Many factors underpin this uncertainty. Biologically, there is much uncertainty about whether forest trees will continue to respond positively to increases in atmospheric CO2 concentration and warmer temperature regimes. Even larger uncertainty exists in relation to fire risks. We have a limited understanding of historical fire regimes in many tropical forests, which differ among biogeographical regions, edaphic factors, vegetation characteristics, and the historical interaction of people with forests. Tropical rain forests, which historically never burned, are now burning in Asia and South America due to human-driven fragmentation and degradation of forests and also because of climate-change-related intensification of heat and drought. Historically and currently, tropical forests with extended dry seasons have been lost earlier and more rapidly than rain forests, as drier forests are easy for people to exploit with the use of fire. Because trees are smaller and less dense in drier forests, they have lower carbon sequestration, both in terms of rate and pool size. Yet, tropical dry forests provide multitudes of ecosystem services, including biodiversity conservation, resource basis to support traditional ecological knowledge, soil conservation, and water regulation. The latter two factors are critical at the watershed and regional levels for the sustainability of the production landscape. It is urgent that we understand the adequate ecosystem fire regimes of remaining natural forests, which hinge heavily on the evolutionary ecological characteristics of tree species that dominate each ecosystem. A scientific understanding of forest fire regimes is urgently needed to provide adequate policy advice to local and national governments, not only to sustain critical ecosystem services provided by the forests but also for landscape-level sustainability of food, water, and energy provisioning.