Changing patterns of fire occurrence in proximity to forest edges, roads and rivers between NW Amazonian countries
Dolors Armenteras1, Joan Sebastian Barreto1, Karyn Tabor2, Roberto Molowny3, and Javier Retana31Laboratorio de Ecología del Paisaje y Modelación de Ecosistemas ECOLMOD, Departamento de Biología, Edif. 421, Of. 223, Universidad Nacional de Colombia, Bogotá, Colombia 2Conservation International, Arlington, VA 22202, USA 3CREAF i Unitat d’Ecología, Universitat Autònoma de Barcelona, 08193 Bellaterra (Barcelona), Spain
Received: 08 Dec 2016 – Accepted for review: 04 Jan 2017 – Discussion started: 12 Jan 2017
Abstract. Tropical forests in NW Amazonia are highly threatened by the expansion of the agricultural frontier and subsequent deforestation. Fire is used, both directly and indirectly, in the Brazilian Amazon to propagate deforestation and increase forest accessibility. Forest fragmentation, a measure of forest degradation, is also attributed to fire occurrence in the tropics. However, outside the Legal Amazonia the role of fire in increasing accessibility and forest fragmentation is less explored. In this study, we compared in five countries sharing this tropical biome in the most North Western part of the Amazon Basin (Venezuela, Colombia, Ecuador, Peru and Brazil). We analysed spatial differences in the timing of peak fire activity and in relation to proximity to roads and rivers using 15 years of MODIS active fire detections. We also distinguished patterns of fire in relation to forest fragmentation by analysing fire distance to the forest edge as a measure of fragmentation for each country. We found significant hemispheric differences in peak fire occurrence with the highest number of fires in the South in 2005 vs. 2007 in the North. we also found difference in peak fire occurrence by country with fire peak in Colombia and Venezuela in February; peak fire in September for Brazil and Peru; and Ecuador presented two fire peaks. We confirmed the relationship between fires and forest fragmentation for all countries; and also found significant differences in the distance of fire to forest edge for each country. These results can inform land use planning at the regional, national and sub-national scale to minimize how road expansion and subsequent access to the amazonian natural resources contribute to fire occurrence, and the associated deforestation and carbon emissions.
Armenteras, D., Barreto, J. S., Tabor, K., Molowny, R., and Retana, J.: Changing patterns of fire occurrence in proximity to forest edges, roads and rivers between NW Amazonian countries, Biogeosciences Discuss., doi:10.5194/bg-2016-532, in review, 2017.