Identifying Post-Fire Recovery Trajectories and Driving Factors Using Landsat Time Series in Fire-Prone Mediterranean Pine Forests

Wildfires constitute the most important natural disturbance of Mediterranean forests, driving vegetation dynamics. Although Mediterranean species have developed ecological post-fire recovery strategies, the impacts of climate change and changes in fire regimes may endanger their resilience capacity. This study aims at assessing post-fire recovery dynamics at different stages in two large fires that occurred in Mediterranean pine forests (Spain) using temporal segmentation of the Landsat time series (1994?2018). Landsat-based detection of Trends in Disturbance and Recovery (LandTrendr) was used to derive trajectory metrics from Tasseled Cap Wetness (TCW), sensitive to canopy moisture and structure, and Tasseled Cap Angle (TCA), related to vegetation cover gradients. Different groups of post-fire trajectories were identified through K-means clustering of the Recovery Ratios (RR) from fitted trajectories: continuous recovery, continuous recovery with slope changes, continuous recovery stabilized and non-continuous recovery. The influence of pre-fire conditions, fire severity, topographic variables and post-fire climate on recovery rates for each recovery category at successional stages was analyzed through Geographically Weighted Regression (GWR). The modeling results indicated that pine forest recovery rates were highly sensitive to post-fire climate in the mid and long-term and to fire severity in the short-term, but less influenced by topographic conditions (adjusted R-squared ranged from 0.58 to 0.88 and from 0.54 to 0.93 for TCA and TCW, respectively). Recovery estimation was assessed through orthophotos, showing a high accuracy (Dice Coefficient ranged from 0.81 to 0.97 and from 0.74 to 0.96 for TCA and TCW, respectively). This study provides new insights into the post-fire recovery dynamics at successional stages and driving factors. The proposed method could be an approach to model the recovery for the Mediterranean areas and help managers in determining which areas may not be able to recover naturally.Ministerio de Ciencia, Innovación y UniversidadesMinisterio de Economía y Competitivida

Assessing post-fire forest structure recovery by combining LiDAR data and Landsat time series in Mediterranean pine forests

Understanding post-fire recovery dynamics is critical for effective management that enhance forest resilience to fire. Mediterranean pine forests have been largely affected by wildfires, but the impacts of both changes in land use and climate endanger their capacity to naturally recover. Multispectral imagery is commonly used to estimate post-fire recovery, yet changes in forest structure must be considered for a comprehensive evaluation of forest recovery. In this research, we combine Light Detection And Ranging (LiDAR) with Landsat imagery to extrapolate forest structure variables over a 30-year period (1990?2020) to provide insights on how forest structure has recovered after fire in Mediterranean pine forests. Forest recovery was evaluated attending to vegetation cover (VC), tree cover (TC), mean height (MH) and heterogeneity (CVH). Structure variables were derived from two LiDAR acquisitions from 2016 and 2009, for calibration and independent spatial and temporal validation. A Support Vector Regression model (SVR) was calibrated to extrapolate LiDAR-derived variables using a series of Landsat imagery, achieving an R2 of 0.78, 0.64, 0.70 and 0.63, and a relative RMSE of 24.4%, 30.2%, 36.5% and 27.4% for VC, TC, MH and CVH, respectively. Models showed to be consistent in the temporal validation, although a wider variability was observed, with R2 ranging from 0.51 to 0.74. A different response to fire was revealed attending to forest cover and height since vegetation cover recovered to a pre-fire state but mean height did not 26-years after fire. Less than 50% of the area completely recovered to the pre-fire structure within 26 years, and the area subjected to fire recurrence showed signs of greater difficulty in initiating the recovery. Our results provide valuable information on forest structure recovery, which can support the implementation of mitigation and adaptation strategies that enhance fire resilience.Comunidad de Madri

Characterizing global fire regimes from satellite-derived products

We identified four global fire regimes based on a k-means algorithm using five variables covering the spatial, temporal and magnitude dimensions of fires, derived from 19-year long satellite burned area and active fire products. Additionally, we assessed the relation of fire regimes to forest fuels distribution. The most extensive fire regime (35% of cells having fire activity) was characterized by a long fire season, medium size fire events, small burned area, high intensity and medium variability. The next most extensive fire regime (25.6%) presented a long fire season, large fire events and the highest mean burned area, yet it showed the lowest intensity and the least variability. The third group (22.07%) presented a short fire season, the lowest burned area, with medium-low intensity, the smallest fire patches and large variability. The fourth group (17.3%) showed the largest burned area with large fire patches of moderate intensity and low variability. Fire regimes and fuel types showed a statistically significant relation (CC = 0.58 and CC? = 0.67, p < 0.001), with most fuel types sustaining all fire regimes, although a clear prevalence was observed in some fuel types. Further efforts should be directed towards the standardization of the variables in order to facilitate comparison, analysis and monitoring of fire regimes and evaluate whether fire regimes are effectively changing and the possible drivers.Agencia Estatal de Investigació

Satellite Remote Sensing contributions to Wildland Fire Science and Management

No funding was received for this particular review, but support research was funded by the European Space Agency’s Climate Change Initiative Programme to Dr. Chuvieco.This paper reviews the most recent literature related to the use of remote sensing (RS) data in wildland fire management. Recent Findings Studies dealing with pre-fire assessment, active fire detection, and fire effect monitoring are reviewed in this paper. The analysis follows the different fire management categories: fire prevention, detection, and post-fire assessment. Extracting the main trends from each of these temporal sections, recent RS literature shows growing support of the combined use of different sensors, particularly optical and radar data and lidar and optical passive images. Dedicated fire sensors have been developed in the last years, but still, most fire products are derived from sensors that were designed for other purposes. Therefore, the needs of fire managers are not always met, both in terms of spatial and temporal scales, favouring global over local scales because of the spatial resolution of existing sensors. Lidar use on fuel types and post-fire regeneration is more local, and mostly not operational, but future satellite lidar systems may help to obtain operational products. Regional and global scales are also combined in the last years, emphasizing the needs of using upscaling and merging methods to reduce uncertainties of global products. Validation is indicated as a critical phase of any new RS-based product. It should be based on the independent reference information acquired from statistically derived samples. The main challenges of using RS for fire management rely on the need to improve the integration of sensors and methods to meet user requirements, uncertainty characterization of products, and greater efforts on statistical validation approaches.European Space Agenc

Compétence en Technologie de l’Information Géographique (TIG) dans les études universitaires: réflexions et propositions participative

El objetivo de este trabajo es ofrecer una reflexión que conduzca a una asignación coherente de competencias en la enseñanza sobre Tecnologías de la Información Geográfica (Cartografía, Sistemas de Información Geográfica y Teledetección) que se imparte en la universidad. Tras analizar diversas propuestas al respecto, en España y a nivel internacional, y a través de una serie de talleres participativos, un grupo de académicos de la Universidad de Alcalá ha generado su propia propuesta sobre las competencias más importantes y necesarias a conseguir en cada nivel de la educación superior (grado, master y doctorado). La propuesta ha sido contrastada con los resultados de una encuesta realizada entre un conjunto de académicos universitarios españoles.The aim of this paper is to offer an insight on competences leading to their consistent allocation in the different courses on Geographic Information Technologies (Cartography, Geographic Information Systems - GIS and Remote Sensing) taught in universities. To do this, after analyzing the various proposals on the subject, both in Spain and internationally, and after conducting a series of participatory workshops, a group of academics from the University of Alcalá has generated its own proposal on the most important and necessary competences to acquire at each level of higher education (bachelor, master and doctorate). Furthermore, the proposal has been contrasted with the results of a survey conducted by a wide range of Spanish university academics.Le but de cet article est de proposer une réflexion conduisant à une allocation cohérente des compétences dans les différents cours sur les technologies d’information géographique (Cartographie, Système d’Information Géographique- SIG et télédétection) enseignées dans les universités. Pour ce faire, après avoir analysé les différentes propositions sur le sujet, à la fois en Espagne et à l’étranger, et après la réalisation d’une série d’ateliers participatifs, un groupe de l’Université de Alcalá a généré sa propre proposition sur les compétences les plus importants et nécessaires pour obtenir à chaque niveau de l’enseignement supérieur (licence, master et doctorat). En outre, la proposition a été contrastée avec les résultats d’une enquête menée par un large éventail d’universitaires espagnols

Propuesta de un sistema espacialmente explícito para evaluar el peligro de incendios

Los incendios forestales suponen un factor muy destacado en la transformación ambiental de buena parte de los ecosistemas terrestres. Tienen impactos globales, afectando a la superficie forestal y a las emisiones de gases de efecto invernadero, y efectos locales, relacionados con la degradación de suelos, erosión, modificación de la dinámica de la vegetación y pérdida de recursos y de vidas humanas. La prevención de incendios resulta cada vez más crítica, para paliar los efectos negativos de los mismos. Se presentan en este trabajo las variables de entrada y el esquema de integración para estimar el peligro de ocurrencia de incendios que se desarrolló en el marco del proyecto Firemap. Se generó información de diversas fuentes, que hacen referencia a variables socio-económicas, así como al estado de los combustibles y las características del territorio, utilizando sistemas de información geográfica (SIG) e imágenes de satélite. Todas las variables se cartografiaron a una resolución espacial de un 1 km2 y se integraron en un servidor web, que estuvo operativo para su evaluación durante el verano de 2007. Se presenta la comparación entre la variación temporal de los índices generados y la ocurrencia observada en la Comunidad de Madrid, una de las regiones del estudio.Forest fires are a major factor of environmental transformation in several ecosystems. Fires have global impacts, affecting forested areas and having an important impact in greenhouse gas emissions. Additionally, fires have local impacts, associated to soil degradation, soil erosion, vegetation dynamics, and lost of lives and properties. Fire prevention is critical to reduce the negative impacts of fire. This paper presents the input variables and the integration scheme developed within the Firemap project (funded under the Spanish Ministry of Science and Technology) to map wildland fire occurrence probability. The project first generated fire risk variables related to several factors of fire ignition or propagation. They were generated from a wide variety of sources using geographic information systems and remote sensing technologies. All variables were mapped at 1 sq km spatial resolution, and were integrated into single indices. The risk system included the development of a dedicated web-mapping server to facilitate the access to the end-users. This service was tested in the summer of 2007 for semi-operational use. The paper presents the first validation results of the danger index, by comparing temporal trends of the different danger components to the fire occurrence in the Madrid region, one of the test sites

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Competencias en Tecnologías de la Información Geográfica (TIG) en los estudios universitarios: reflexión y propuesta participativas

The aim of this paper is to offer an insight on competences leading to their consistent allocation in the different courses on Geographic Information Technologies (Cartography, Geographic Information Systems - GIS and Remote Sensing) taught in universities. To do this, after analyzing the various proposals on the subject, both in Spain and internationally, and after conducting a series of participatory workshops, a group of academics from the University of Alcalá has generated its own proposal on the most important and necessary competences to acquire at each level of higher education (bachelor, master and doctorate). Furthermore, the proposal has been contrasted with the results of a survey conducted by a wide range of Spanish university academics.Le but de cet article est de proposer une réflexion conduisant à une allocation cohérente des compétences dans les différents cours sur les technologies d’information géographique (Cartographie, Système d’Information Géographique- SIG et télédétection) enseignées dans les universités. Pour ce faire, après avoir analysé les différentes propositions sur le sujet, à la fois en Espagne et à l’étranger, et après la réalisation d’une série d’ateliers participatifs, un groupe de l’Université de Alcalá a généré sa propre proposition sur les compétences les plus importants et nécessaires pour obtenir à chaque niveau de l’enseignement supérieur (licence, master et doctorat). En outre, la proposition a été contrastée avec les résultats d’une enquête menée par un large éventail d’universitaires espagnols.El objetivo de este trabajo es ofrecer una reflexión que conduzca a una asignación coherente de competencias en la enseñanza sobre Tecnologías de la Información Geográfica (Cartografía, Sistemas de Información Geográfica y Teledetección) que se imparte en la universidad. Tras analizar diversas propuestas al respecto, en España y a nivel internacional, y a través de una serie de talleres participativos, un grupo de académicos de la Universidad de Alcalá ha generado su propia propuesta sobre las competencias más importantes y necesarias a conseguir en cada nivel de la educación superior (grado, master y doctorado). La propuesta ha sido contrastada con los resultados de una encuesta realizada entre un conjunto de académicos universitarios españoles