Alejandro Miranda

University of La Frontera · Department of Forest Science

Wildfires and drought stressors can significantly limit forest recovery in Mediterranean-type ecosystems. Since 2010, the region of central Chile has experienced a prolonged Mega Drought, which intensified into a Hyper Drought in 2019, characterized by record-low precipitation and high temperatures, further constraining forest recovery. This study...

This study investigates the national expansion of urban and artificial coverages in Chile between 2000 and 2022 using remote sensing techniques. The research employed Google Earth Engine and Landsat imagery to classify land use and land cover (LULC) changes. By analyzing annual cloud-free composites and employing random forest algorithms, the study...

The interplay between wildfires and drought stress has significantly limited forest recovery in the Mediterranean ecosystem of central Chile. Since 2010, the region has faced a prolonged 'Mega Drought,' which intensified into a 'Hyper Drought' in 2019, with record-low precipitation and high temperatures, further constraining forest recovery amidst...

Plant flammability research has proven pivotal in comprehending the contribution of vegetation to the flammability of forest ecosystems. Yet, the relationship between many leaf chemical traits and plant flammability is poorly understood. While terpenes and some leaf nutrients in plants have been extensively studied for their role in flammability, a...

Background The potential ecosystem collapse of forests in Mediterranean-type ecosystems (MTEs) by unprecedented droughts is worrisome due to the impacts on its exceptional biodiversity and human well-being. However, research integrating the impacts of global change drivers, forest resilience and the challenges facing human-nature relationships is s...

Aim Biodiversity monitoring at global scales has been identified as one of the priorities to halt biodiversity loss. In this context, Latin America and the Caribbean (LAC), home to 60% of the global biodiversity, play an important role in the development of an integrative biodiversity monitoring platform. In this review, we explore to what extent L...

Monitoring wildfires is an essential step in minimizing their impact on the planet, understanding the many negative environmental, economic, and social consequences. Recent advances in remote sensing technology combined with the increasing application of artificial intelligence methods have improved real-time, high-resolution fire monitoring. This...

The conservation of forest landscapes is crucial for global climate strategies, and the forest in Tierra del Fuego, located in Patagonia, represents the southernmost example on Earth. These ecosystems are critical for Chile’s roadmap toward carbon neutrality. Unfortunately, these ecosystems have been impacted by logging and beaver activities. Curre...

Large-scale, abrupt ecosystem change in direct response to climate extremes is a critical but poorly documented phenomenon¹. Yet, recent increases in climate-induced tree mortality raise concern that some forest ecosystems are on the brink of collapse across wide environmental gradients2,3. Here we assessed climatic and productivity trends across t...

Questions Facilitation by pioneer plants and herbivore exclusion may contribute to plant regeneration and restoration of degraded semiarid ecosystems. In this study we evaluated the main and interactive effects of the exclusion of large and medium‐sized mammal herbivores and the presence of the pioneer tree Vachellia caven on natural regeneration o...

Context Western 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 func...

A solution approach is proposed to optimize the selection of landscape cells for inclusion in firebreaks. It involves linking spatially explicit information on a landscape’s ecological values, historical ignition patterns and fire spread behavior. A firebreak placement optimization model is formulated that captures the tradeoff between the direct l...

Context Western Chilean Patagonia is an isolated temperate region with a proportion of 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 rate and the effect on the landscape structure and function, and remanent IFL following t...

A solution approach is proposed to optimize the selection of landscape cells for inclusion in firebreaks. It involves linking spatially explicit information on a landscape’s ecological values, historical ignition patterns and fire spread behavior. An MIP firebreak siting optimization model is formulated that captures the tradeoff between the direct...

Achieving a local understanding of fire regimes requires high-resolution, systematic and dynamic databases. High-quality information can help to transform evidence into decision-making in the context of rapidly changing landscapes, particularly considering that geographical and temporal patterns of fire regimes and their trends vary locally over ti...

Ecosystem collapse in direct response to climate change is a critical but poorly documented phenomenon. By assessing the climate context and productivity trends in Mediterranean ecosystems worldwide, we found a large-scale, abrupt forest decline in Chile (>90% in <100 days) as response to a sustained, acute drought unprecedented in the recent histo...

Achieving a local understanding of fire regimes requires high resolution, systematic and dynamic databases. Highquality information can help to transform the evidence into decision-making in the context of rapidly changing landscapes, particularly considering that geographical and temporal patterns of fire regimes and their trends vary locally over...

Recolonization of wind-dispersed tree species in degraded areas may decline with distance from remnant forest fragments because seed rain frequently decreases with distance from the seed source. However, regeneration of these species may be even more limited to sites close to the seed source if dispersal distance is negatively affected by seed mass...

The growing demand for timber and the boom in massive tree-planting programs could mean the spreading of mismanaged tree plantations worldwide. Here, we apply the concept of ecological intensification to forestry systems as a viable biodiversity-focused strategy that could be critical to develop productive, yet sustainable, tree plantations. Tree p...

Fire plays a dominant role in deforestation, particularly in the tropics, but the relative extent of transformations and influence of fire frequency on eventual forest loss remain unclear. Here, we analyze the frequency of fire and its influence on postfire forest trajectories between 2001 and 2018. We account for ~1.1% of Latin American forests bu...

Freshwater inputs strongly influence oceanographic conditions in coastal systems of northwestern Patagonia (41–45°S). Nevertheless, the influence of freshwater on these systems has weakened in recent decades due to a marked decrease in precipitation. Here we evaluate potential influences of climate and land cover trends on the Puelo River (640 m³s–...

Increasing wildfire activity globally has become an urgent issue with enormous ecological and social impacts. In this work, we focus on analyzing and quantifying the influence of landscape topology, understood as the spatial structure and interaction of multiple land-covers in an area, on fire ignition. We propose a deep learning framework, Deep Fi...

The strong link between climate change and increased wildfire risk suggests a paradigm change on how humans must co-exist with fire and the environment. Different studies have demonstrated that human-induced fire ignitions can account for more than 90 % of forest fires, so human coexistence with wildfires requires informed decision making via preve...

As president of the Climate Change Conference of the Parties, Chile has advocated for developing ambitious commitments to mitigate greenhouse gas emissions to achieve carbon-neutrality by 2050. However, Chile’s motivations and ambitious push to reach carbon-neutrality are complicated by a backdrop of severe drought, climate change impacts (i.e., wi...

Data collection from large areas of native forests poses a challenge. The present study aims at assessing the use of UAV for forest inventory on native forests in Southern Chile, and seeks to retrieve both stand and tree level attributes from forest canopy data. Data were collected from 14 plots (45 × 45 m) established at four locations representin...

Data collection from large areas of native forests poses a challenge. The present study aims at assessing the use of UAV for forest inventory on native forests in Southern Chile, and seeks to retrieve both stand and tree level attributes from forest canopy data. Data were collected from 14 plots (45 × 45 m) established at four locations representin...

Increasing wildfire activity across the globe has become an urgent issue with enormous ecological and social impacts. While there is evidence that landscape topology affects fire growth, no study has yet reported its potential influence on fire ignition. This study proposes a deep learning framework focused on understanding the impact of different...

Much progress has been made in remotely detecting forest loss, particularly by using satellite imagery. However, quantification of different stages of forest degradation continues to be challenging. Compared with satellites, UAVs (or drones) can deliver images of much higher spatial resolution and enable estimation of forest characteristics with gr...

Distinguising between natural forests from exotic tree plantations is essential to get an accurate picture of the world’s state of forests. Most exotic tree plantations support lower levels of biodiversity and have less potential for ecosystem services supply than natural forests, and differencing them is still a challenge using standard tools. We...

En el presente informe se resume la estrategia de evaluación del Riesgo climático en bosque nativo y en plantaciones forestales ante incendios forestales, y la evaluación del efecto directo del clima en la productividad fotosintética de ambos sistemas en función de los cambios recientes en precipitación y temperatura.

The wildland-urban interface (WUI) is the spatial manifestation of human communities coupled with vegetated ecosystems. Spatial delineation of the WUI is important for wildfire policy and management, but is typically defined according to spatial relationships between housing development and wildland vegetation without explicit consideration of fire...

Understanding of people’s landscape preferences is important for decision-making about land planning, particularly in the disturbance patterns that usually occur in rural-urban gradients. However, the use of different types of images concerning the same landscape may influence social preferences and thus perceptions of landscape management and plan...

Deforestation is widely studied throughout the world. However, a less evident issue is the effect of climate change and drought on remnants of native forests. The objective of this work was to understand the geographic variations in resistance to drought of the Mediterranean sclerophyllous forests of central Chile. These forests have been historica...

Los resultados presentados en este informe son parte del trabajo interdisciplinario que realiza el Centro de Ciencia del Clima y la Resiliencia (CR)2. El (CR)2 es un centro de excelencia financiado por el programa FONDAP de CONICYT (Proyecto 15110009) en el cual participan cerca de 60 científicos asociados a la Universidad de Chile, la Universidad...

La submesa Cambio de Uso del Suelo (CUS) tuvo como objetivo compilar y presentar en un informe la evidencia científica disponible sobre los cambios de uso del suelo y sus impactos en relación con las opciones de mitigación del cambio climático. Esta submesa contó con la participación de más de 30 científicos de diversas áreas de las ciencias ambien...

http://www.inap.uchile.cl/publicaciones/159662/informe-pais-estado-del-medio-ambiente-en-chile-2018

https://science.sciencemag.org/content/366/6470/1207.full

The presence and attributes of perch trees in degraded areas may promote seed dispersal. We evaluated the effect of the distance from remnant forest fragments on seed rain of different fleshy-fruit tree species and examined whether the seed rain is favoured by some traits of the perch trees (Acacia caven), such as canopy diameter and tree height. T...

In this poster we present a series of practical and methodological guidelines for correctly operating UAV's and collecting data for scientific studies. This guidelines are based on our experience of monitoring landscapes in extreme weather conditions such as those found in north-western Patagonia, Chile, where high nubosity, intermitent rain and hi...

En el siglo XXI, el desarrollo de Chile está en juego debido a las amenazas planteadas por el Antropoceno. Esta época se caracteriza por la influencia humana sobre el sistema terrestre. Sin embargo, si se enfrenta con audacia, ofrece una oportunidad para un desarrollo sostenible. Independientemente de si hemos entrado en una nueva era geológica, el...

Guidance for large-scale restoration of natural or semi-natural linear vegetation elements that takes into account the need to maintain human livelihoods such as farming is often lacking. Focusing on a Chilean biodiversity hotspot, we assessed the landscape in terms of existing woody vegetation elements and proposed a buffer strip and hedgerow netw...

El monitoreo de los bosques es fundamental para la toma de decisiones de manejo y conservación. En Chile, el sistema de monitoreo de bosques se inició en el año 1994, y se ha mantenido mediante la realización de actualizaciones regionales. Esto ha permitido hacer un seguimiento temporal de la superficie, distribución y características del bosque na...

The understanding of the spatial and temporal patterns in land use and land cover (LULC) change is a key issue for conservation efforts. In the Chilean hotspot, different studies have attempted to understand variations of LULC change. Nevertheless, a broader understanding of common patterns and variability of LULC over the entire range of the hotsp...

Ulex europaeus (gorse) is an invasive shrub deemed as one of the most invasive species in the world. U. europaeus is widely distributed in the south-central area of Chile, which is considered a world hotspot for biodiversity conservation. In addition to its negative effects on the biodiversity of natural ecosystems, U. europaeus is one of the most...

Jubaea chilensis es un árbol endémico de la zona central de Chile (31º15’- 35º22’ S). Las principales amenazas actuales a su conservación estarían asociadas a diferentes limitantes a su regeneración natural, en especial la intensa cosecha de sus semillas. El análisis de patrones espaciales de distribución puede ser una importante herramienta para e...

Jubaea chilensis is an endemic tree of Central Chile (31º15’-35º22’ S). The current main conservation threats for this species should be associated with different factors which limit its natural regeneration, in particular the intense seeds crop. The analysis of spatial distribution patterns can be an important tool to understand the forest dynamic...

Jubaea chilensis is an endemic tree of Central Chile (31º15’- 35º22’ S). The current main conservation threats for this species should be associated with different factors which limit its natural regeneration, in particular the intense seeds crop. The analysis of spatial distribution patterns can be an important tool to understand the forest dynami...

Cultivated land has increased in Chile as a result of a process in which native woodland sites were converted to agricultural production. This process had an intermediate step in which sclerophyll species were replaced by Acacia caven, prior to cattle grazing. This land use change presents environmental impacts resulting from carbon losses of ecosy...

Forest biomass is one of the main alternatives that Chile could promote to supply the long-term demand of energy, which can help to diversify the national energy offer. In this study we assessed the biomass availability from native forests, considering biomass extraction based on silvicultural management and environmental and legal restrictions in...

Keywords: Deforestation Timber plantation Chilean temperate forest Land use e land cover change a b s t r a c t Temperate forest represents the smallest area among the main world's forest biomes, but is one of those most threatened by forest loss. Chile contains most of the temperate forest in South America and more than half of the temperate fores...

Folleto de difusión resultados de Investigación Proyecto del Fondo de Investigación del Bosque Nativo 057/2012.

Loss of native forest is a key conservation concern globally, for reasons of biodiversity, climate change and ecosystem services. Landscape measures are used widely to characterize forest loss and associated landscape structure, but often without regard for structure imposed by the data used, and associated assumptions. Notably, forest loss is ofte...

The Juan Fernandez Archipelago World Biosphere Reserve (33º S) contains the highest density of insular floral endemism in the world. Currently three invasive woody plant species threaten the conservation of the vegetation of Juan Fernández, particularly on Robinson Crusoe Island. The introduced plant species, Aristotelia chilensis (maqui), Rubus ulm...

The Juan Fernandez Archipelago World Biosphere Reserve (33° S) contains the highest density of insular floral endemism in the world. Currently three invasive woody plant species threaten the conservation of the vegetation of Juan Fernández, particularly on Robinson Crusoe Island. The introduced plant species, Aristotelia chilensis (maqui), Rubus ul...

Se estableció un ensayo a largo plazo para determinar el potencial totalmente expresado de la capacidad de recuperación del bosque esclerófilo. Se evaluaron: 1) los efectos de la exclusión de herbívoros en áreas con Acacia caven cercanas a bosque esclerófilo; y 2) las condiciones que pueden aumentar el éxito de medidas de restauración pasiva. Dur...

Natural regeneration of mediterranean plant communities has proved difficult in all continents. In this paper we assess whether regeneration of sclerophyllous forests shows nucleated patterns indicative of a positive effect of vegetation remnants at the landscape level and compare the regeneration patterns between sites with distinctive climate con...