Increasing evidence indicates that forest disturbances are changing in response to global change, yet local variability in disturbance remains high. We quantified this considerable variability and analyzed whether recent disturbance episodes around the globe were consistently driven by climate, and if human influence modulates patterns of forest disturbance. We combined remote sensing data on recent (2001–2014) disturbances with in-depth local information for 50 protected landscapes and their surroundings across the temperate biome. Disturbance patterns are highly variable, and shaped by variation in disturbance agents and traits of prevailing tree species. However, high disturbance activity is consistently linked to warmer and drier than average conditions across the globe. Disturbances in protected areas are smaller and more complex in shape compared to their surroundings affected by human land use. This signal disappears in areas with high recent natural disturbance activity, underlining the potential of climate-mediated disturbance to transform forest landscapes.

Citation: Gonz alez, M. E., S. G omez-Gonz alez, A. Lara, R. Garreaud, and I. D ıaz-Hormaz abal.Abstract. Forest fire activity has increased in recent years in central and south-central Chile. Drought conditions have been associated with the increase of large wildfires, area burned and longer fire seasons. This study examines the influence of drought on fire regimes and discusses landscape management opportunities to decrease fire hazard. Specifically, we investigate the effect of the 2010-2015 Megadrought (MD) compared to 1990-2009 period on fire activity (fire-season length, number of fires and burned area across months, fire sizes, regions and vegetation cover types, simultaneity, and duration of fires) in central and south-central Chile (32°-39°S), using contemporary fire statistics derived from the Chilean Forest Service. For large fire events (>200 ha) the average season length increased by 67 d (44%), comparing 2010-2015 to 1990-2009. Earlier and later ignition dates resulted in extended fire seasons in MD years. During the MD, the number, area burned, simultaneity, and duration of large fires increased significantly compared to the control period, including the unprecedented occurrence of large fires during winter. The burned area in large fires increased in all vegetation types, during the MD compared to the control period, especially in the exotic plantation cover type. The regions that were most affected by fire (i.e., total area burned) during the MD were Maule, B ıo-B ıo, and Araucan ıa (35-39°S) that concentrate >75% of forest plantations in Chile. Although both maximum temperatures and precipitation are drivers of fire activity, a simple attribution analysis indicates that the sustained rainfall deficit during 2010-2015 was the most critical factor in the enhanced fire activity. Future climate change predictions indicate more recurrent, intense, and temporally extended droughts for central and south-central Chile. Under this scenario, land-use planning and fire and forest management strategies must promote a more diverse and less flammable landscape mosaic limiting high load, homogenous, and continuous exotic plantations.

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SUMMARYIn the last decades, forest fires have been a concern in different regions of the world, especially by increased occurrences product of human activities and climate changes. In this study the spatio-temporal trends in the occurrence and area affected by fire in the Maule region during the period 1986-2012 were examined. We use the Corporación Nacional Forestal fire database, whose records were spatially represented by a grid of 2x2 km. The occurrence was stable during the analyzed period with an average of 378 events per year. The burned area presented three periods above average with 5.273 hectares per year. Most of the fires affected surfaces of less than 5 hectares, while a very small number of events explain most of the area annually burned in the region. According to the startup fuel, we found an increasing number of events initiated in forest plantations in contrast to the decreasing number of fires originated in the native forests. Causes of fires associated with transit and transportation were the most important. The number of events accidentally caused by burning waste significantly increased in the period studied. Most of the fires occurred in the coastal area and the central valley, strongly associated with the road network and the most populated cities. This work represents an important contribution to the characterization of forest fires in the region of Maule, being the first to represent the fire statistics in Chile in a spatially explicit way.Key words: rotation period, causes and origin of fires, fire regime. RESUMENEn las últimas décadas, los incendios forestales han sido una preocupación en distintas regiones del mundo, especialmente, por el incremento en su ocurrencia producto de actividades humanas y cambios en el clima. En este estudio se examinaron las tendencias espacio-temporales en la ocurrencia y superficie afectada por incendios en la región del Maule durante el período 1986-2012. Se utilizó la base de datos de incendios de la Corporación Nacional Forestal, cuyos registros fueron representados espacialmente mediante una grilla de 2x2 km. La ocurrencia se mantuvo estable durante el periodo analizado con un promedio de 378 eventos por año. La superficie quemada presentó tres periodos por sobre el promedio de 5.273 hectáreas al año. La mayor parte de los incendios afectó superficies < 5 ha, mientras que un número muy pequeño de eventos explicaron la mayor parte del área quemada anualmente en la región. Según el combustible de inicio, aumentaron aquellos eventos iniciados en plantaciones forestales y disminuyeron aquellos originados en bosque nativo. Las causas de incendios asociadas al tránsito y al transporte resultaron ser las más importantes. El número de eventos causados accidentalmente por quema de desechos aumentó significativamente en el periodo estudiado. La mayor parte de los incendios se localiza en la zona costera y en el llano central, fuertemente asociados a la red vial y a las ciudades más pobladas. Este trabajo es una contribución a la caracterización de los incendi...

Forest degradation continues to increase globally, threatening biodiversity and the survival of species. In this context, identifying intact, old-growth forest stands is both urgent and vital to ensure their existence and multiple contributions to society. Despite the global ecological importance of the Valdivian temperate rainforests, they are threatened by forest degradation resulting from constant and intense human use in the region. Identification of remnant intact forests in this region is urgent to global forest protection efforts. In this paper, we analyzed whether forests-canopy alterations due to logging produce a distinctive canopy gap structure (e.g., a gap area and a fraction of canopy gaps in the forest) that can be used to remotely distinguish intact from altered forests. We tested this question by comparing the canopy gap structure of 12 old-growth temperate rainforests in south-central Chile (39–40° S), with different levels of canopy alterations due to logging. At each stand, we obtained aerial or satellite very high spatial-resolution images that were automatically segmented using the Mean-Shift segmentation algorithm. We validated the results obtained remotely with ground data on the canopy gap structure. We found that, in the variables, canopy gap fraction, gap area frequency distribution, and mean gap area could be measured remotely with a high level of accuracy. Intact forests have a distinct canopy gap structure in comparison to forests with canopy alterations due to logging. Our results provided a fast, low-cost, and reliable method to obtain canopy gap structure indicators for mapping and monitoring intact forests in the Valdivian ecoregion. The method provided valuable information for managers interested in maintaining and restoring old-growth forest structures in these southern-temperate rainforests.

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Abstract. The Chilean SNASPE is a complex network of 104 protected areas covering 18.5 million hectares of continental and insular Chile in South America. The geographical complexity and high biodiversity of the SNASPE make difficult to develop a unified monitoring system for conservation and management. In this contribution, we introduce a novel and remote-sensing web-platform for monitoring SNASPE units based completely in open acces data and software. The platform was designed in close cooperation with the Chilean forest service CONAF in order to make it applicable to the whole SNASPE. Following the framework of the Group on Earth Observation - Biodiversity Observation Network (GEO-BON), we used the Essential Biodiversity Variable (EBV) Phenology and MODIS Enhanced Vegetation Index (EVI) data to detect in near-real-time anomalies from the normal annual phenological cycle of vegetation. The platform is based on a flexible non-parametric probabilistic algorithm (the “npphen” R package) capable to reconstruct any type of leaf phenology and to quantify its inter-annual variation by means of confidence intervals around the most probable annual curve. Phenological anomalies are then calculated as a deviation from the expected annual cycle and judged based on their location within the confidence intervals. Anomalies located above 95% confidence interval trigger a “red alert” which is displayed on the web application as soon as the MODIS data become available. This user-friendly platform was implemented in the La Campana National Park giving early alerts of a severe drought in 2019, warning Conaf to implement actions to protect the park from potential wild fires.