The quantitative signal for the association of fires and land cover change is strong and the impact of frequent fires is vast.

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 Brazilian Amazonia 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 Brazilian Legal Amazonia the role of fire in increasing accessibility and forest fragmentation is less explored. In this study, we compared fire regimes in five countries that share this tropical biome in the most north-westerly 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 12 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. Despite this, both hemispheres are equally affected by fire. We also found difference in peak fire occurrence by country. Fire peaked in February in Colombia and Venezuela, whereas it peaked in September in Brazil and Peru, and finally Ecuador presented two fire peaks in January and October. We confirmed the relationship between fires and forest fragmentation for all countries and also found significant differences in the distance between the fire and the forest edge for each country. Fires were associated with roads and rivers in most countries. These results can inform land use planning at the regional, national and subnational scales to minimize the contribution of road expansion and subsequent access to the Amazonian natural resources to fire occurrence and the associated deforestation and carbon emissions.

A fire probability map is an important tool for landscape management, providing better identification of areas prone to fires and helping optimize the allocation of limited resources for fire prevention, control, and management. In this study, the random forest machine learning algorithm was applied to model the probability of fire occurrence in the Colombian-Venezuelan plains (llanos) ecoregion in South America. Information on burned areas was collected using Moderate Resolution Imaging Spectroradiometer (MODIS) Product MCD64A1 for the period 2015–2019. We also used spatial information of related factors that were grouped into four levels of information: topography, human presence, vegetation, and climate-related variables. The model had an accuracy of 94%, which indicates the performance of the model was excellent. The cartography generated from the model can be used as base information in the context of fire management in the region, to identify areas for prioritizing efforts and attention. The probability of occurrence zoning results indicates that the very low category covers the largest area (28.2%), followed by low (23.2%), very high (17.6%), moderate (17.2%), and high (13.8%).

The native savanna ecosystem of the Orinoquia region is the habitat of 50% of the wild ungulate species reported for Colombia. Over the last 20 years, this high species diversity has been strongly threatened by the human transformation of the natural land cover causing connectivity loss of the habitats. The Orinoquia region lacks a biological connectivity analysis with a multi-species approach involving species groups that are representative of the savanna ecosystem such as the ungulates. Understanding the spatial distributions of suitable areas and the main habitats that act as primary habitats for ungulate species in these landscapes is fundamental for the design of conservation strategies. We use an occurrence dataset for lowland tapir (Tapirus terrestris), white-tailed deer (Odocoileus virginianus), and white-lipped peccary (Tayassu pecari) in the development of species’ potential distribution models, binarization process, and morphological spatial pattern analysis. This information was used for the modeling of dispersal corridors connecting the core habitats of the ungulate focal species using the randomized shortest path algorithm and quantifying the weighted global connectivity metrics. Our results suggest an integral corridor with potential least-cost dispersal routes between the native savanna landscape on the middle basins of the savanna rivers and the Meta River. These areas associated with the fluvial dendritic systems are connected, while the core habitats in the eastern part of the savanna landscape are disconnected. We discuss how the application of such knowledge on the spatial ecology of ungulate focal species might improve the management of the metapopulations in the Orinoquia region.

The lack of knowledge about the distributional patterns of threatened ungulates hinders the implementation of effective strategies for the conservation of their populations in Neotropical savannas. The Orinoquia is one of those ecoregions with limited data, poorly represented in the Colombian National System of Protected Areas. Nevertheless, the savannas of the Orinoquia serve as the habitat for 70% of the ungulate species reported in the country. The objective of our research was to identify the presence of the lowland tapir (Tapirus terrestris) and evaluate its representation in different land cover types and within Protected Areas (PAs) in the department of the Vichada. To accomplish this, we: (i) modeled the ecological niche of the lowland tapir using the MaxEnt algorithm, (ii) classified the potential distribution into three zones of habitat suitability, and (iii) assessed the representativeness of habitat suitability within the land cover of the savanna ecosystem and PAs. The suitable area for the lowland tapir was 134,575 km², with the most representative savanna landscapes being: (i) savannas (118,125 km², 87.8%) and (ii) evergreen broadleaf forests (12,550 km², 9.3%). Furthermore, (2,925 km², 2.2%) of the suitable area was reported within of the Natural Reserves of Civil Society. Our results highlight the ecological importance of private conservation initiatives as a complementary strategy to government PAs as well as contributing to functional connectivity on the regional scale. We provide information on the spatial ecology of the lowland tapir as an input for conservation practitioners and land planning in the savanna of eastern Colombia.

La acción del hombre y la variabilidad climática asociada al calentamiento global está afectando la incidencia de fuegos en las regiones tropicales, aumentando tanto su intensidad como su frecuencia, particularmente en periodos de sequías. En este estudio se realizó un análisis espacio temporal para identificar la ocurrencia de fuegos dentro y fuera de áreas protegidas en el noroeste de la Amazonía. El objetivo fue analizar la efectividad de estas figuras de protección o manejo en los países de la región en términos de reducción de la afectación por incendios. Se utilizaron datos de focos activos de fuegos detectados por sensores remotos (MODIS) para el periodo comprendido entre diciembre del año 2000 hasta febrero del año 2015 en Brasil, Colombia, Ecuador, Perú y Venezuela. Se siguió la denominación asignada por La Unión Internacional para la Conservación de la Naturaleza (IUCN), las áreas protegidas presentes en la región se agruparon en tres categorías, y la dinámica de los incendios fue analizada a diferentes niveles de estudio. Los resultados indican que las áreas protegidas presentan en todos los casos una menor densidad de fuegos, a diferencia de territorios sin ningún tipo de protección. En términos de comparación de la efectividad, se presenta una mayor cantidad de fuegos en la categoría de resguardo indígena, mientras que la mayor densidad de fuegos por km2 ocurre en áreas tipo categorías II-III. Los resultados obtenidos mostraron que la presencia de áreas protegidas en el noroeste de la Amazonía es efectiva para mitigar la incidencia de fuegos forestales.