Consequences of land-use change and the wildfire disaster of 2017 for the central Chilean biodiversity hotspot

Abstract

Central Chile is an important biodiversity hotspot in Latin America. Biodiversity hotspots are characterised by a high number of endemic species cooccurring with a high level of anthropogenic pressure. In central Chile, the pressure is caused by land-use change, in which near-natural primary and secondary forests are replaced and fragmented by commercial pine and eucalyptus plantations. Large forest fires are another factor that can potentially endanger biodiversity. Usually, environmental hazards, such as wildfires, are part of the regular environmental dynamic and not considered a threat to biodiversity. Nonetheless, this situation may change if land-use change and altered wildfire regimes coerce. Land-use change pressure may destroy landscape integrity in terms of habitat loss and fragmentation, while wildfires may destroy the last remnants of native forests. This study aims to understand the joint effects of land-use change and a catastrophic wildfire on habitat loss and habitat fragmentation of local plant species richness hotspots in central Chile. To achieve this, we apply a combination of ecological fieldwork, remote sensing, and geoprocessing to estimate the spread and spatial patterns of biodiverse habitats under current and past land-use conditions and how these habitats were altered by land-use change and by a single large wildfire event. We show that land-use change has exceeded the wildfire’s impacts on diverse habitats. Despite the fact that the impact of the wildfire was comparably small here, wildfire may coerce with land-use change regarding pressure on biodiversity hotspots. Our findings can be used to develop restoration concepts, targeting on an increase of habitat diversity within currently fire-cleared areas and evaluate their benefits for plant species richness conservation.