Forest landscape dynamics after intentional large-scale fires in western Patagonia reveal unusual temperate forest recovery trends

ContextWestern Chilean Patagonia is an isolated temperate region with an important proportion of intact forest landscapes (IFL) that was subjected to large-scale fires over 60 years ago. However, there is no empirical evaluation of the land cover dynamics to establish the forest loss and recovery, and the effect on the landscape structure and function, and remnant IFL following the fires.ObjectivesThe present study addressed the following questions: (1) What have been the main trends of the land cover dynamics between 1984 and 2018 following earlier fires, and how have these trends shaped the spatial patterns and potential carbon stock of forests in western Patagonia? (2) What proportion of forest landscape remains intact following fires in this region?MethodsWe selected the Coyhaique Province (1,231,910 ha) in western Chilean Patagonia as the study area. Land cover maps for three dates (1984, 2000, 2018) were used to evaluate landscape dynamics after fires. A map of persistence and change occurrence was made to estimate the IFL area over the 1984-2018 period. Landscape metrics were used to assess landscape structure change, and potential carbon stock was estimated based on a literature review.ResultsFollowing fires, the main land cover changes between 1984 and 2018 were loss of similar to 32,600 ha of old-growth forest and a recovery of similar to 69,000 ha of second-growth forest. The increase in second-growth forest area mainly resulted from loss of agricultural cover (similar to 41% of the area). Despite these changes, similar to 61% of the area could potentially remain as IFL after fires. Over the 1984-2018 period, a slight increase in fragmentation of old-growth forest, and a decline in second-growth forest were observed. Coyhaique Province experienced a slight increase (3.6%) in overall potential carbon stock, likely as a result of second-growth forest recovery.ConclusionsOur study provides the first evidence of the western Patagonia landscape state after more than six decades since the large-scale fires. The results provide baseline information on landscape structure and function that could help to make conservation and forest management decisions on specific territory areas.