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Background Wildfires play a key role in shaping Mediterranean landscapes and ecosystems and in impacting species dynamics. Numerous studies have investigated the wildfire occurrences and the influence of their drivers in many countries of the Mediterranean Basin. However, in this regard, no studies have attempted to compare different Mediterranean regions, which may appear similar under many aspects. In response to this gap, climatic, topographic, anthropic, and landscape drivers were analyzed and compared to assess the patterns of fire ignition points in terms of fire occurrence and frequency in Catalonia (Spain), Sardinia, and Apulia (Italy). Therefore, the objectives of the study were to (1) assess fire ignition occurrence in terms of probability and frequency, (2) compare the main drivers affecting fire occurrence, and (3) produce fire probability and frequency maps for each region. Results In pursuit of the above, the probability of fire ignition occurrence and frequency was mapped using Negative Binomial Hurdle models, while the models’ performances were evaluated using several metrics (AUC, prediction accuracy, RMSE, and the Pearson correlation coefficient). The results showed an inverse correlation between distance from infrastructures (i.e., urban roads and areas) and the occurrence of fires in all three study regions. This relationship became more significant when the frequency of fire ignition points was assessed. Moreover, a positive correlation was found between fire occurrence and landscape drivers according to region. The land cover classes more significantly affected were forest, agriculture, and grassland for Catalonia, Sardinia, and Apulia, respectively. Conclusions Compared to the climatic, topographic, and landscape drivers, anthropic activity significantly influences fire ignition and frequency in all three regions. When the distance from urban roads and areas decreases, the probability of fire ignition occurrence and frequency increases. Consequently, it is essential to implement long- to medium-term intervention plans to reduce the proximity between potential ignition points and fuels. In this perspective, the present study provides an applicable decision-making tool to improve wildfire prevention strategies at the European level in an area like the Mediterranean Basin where a profuse number of wildfires take place.

Today, a forest is also understood as a real social actor with multiple-scale influences, capable of significantly conditioning the social, economic, and cultural system of a whole territory. The aim of this paper is to reconstruct and interpret the population&rsquo, s perception of the silvicultural activities related to traditional use of forest resources of the southwestern Sardinian Marganai State Forest. The &ldquo, Marganai case&rdquo, has brought to the attention of the mass media the role of this forest and its silviculture. The research was carried out via semi-structured interviews with the main stakeholders in the area. The qualitative approach in the collection and analysis of the information gathered has allowed us to reconstruct the historical-cultural and social cohesion function that the forest plays in rural communities. The results highlight that the main risks concern the erosion of the cultural forest heritage due to the abandonment of the rural dimension (mainly by the new generations, but not only), with the consequent spread of deep distortions in the perception, interpretation, and necessity of forestry activities and policy.

The practice of coppicing is debated in the literature for the risk factors associated with soil erosion. Although erosion experiments provide useful data for estimating the susceptibility to soil erosion, there are many open questions that cannot be solved in isolated experiments, but which can be assessed by activating a long-term monitoring process. In this way, it is possible to correctly frame the spatial and temporal scale of soil erosion in coppice forests. The aim of the work is to evaluate the effectiveness of the use of remote sensing data in combination with field data, for monitoring the evolution of forest stands interested by coppicing in relation to soil erosion. We have installed a long-term monitoring network for erosion estimation, while Sentinel-2C satellite data were used for the period 2016-2018. Starting from this dataset, a selection of vegetation indices was calculated and compared to the morphological and topographical parameters of the study area, as well as the above-ground data collected during field activities. Using the Canonical Correspondences Analysis (CCA) the relationships between the matrix of vegetation indices, topographic and vegetational parameters and the respective performances of this protocol have been explored in order to describe the evolution of the forest stands in the study area associated to soil losses.

Sardinia (Italy), the second largest island of the Mediterranean Sea, is a fire-prone land. Most Sardinian environments over time were shaped by fire, but some of them are too intrinsically fragile to withstand the currently increasing fire frequency. Calcareous pedoenvironments represent a significant part of Mediterranean areas, and require important efforts to prevent long-lasting degradation from fire. The aim of this study was to assess through an integrated multiple approach the impact of a single and highly severe wildland fire on limestone-derived soils. For this purpose, we selected two recently burned sites, Sant'Antioco and Laconi. Soil was sampled from 80 points on a 100 × 100 m grid – 40 in the burned area and 40 in unburned one – and analyzed for particle size fractions, pH, electrical conductivity, organic carbon, total N, total P, and water repellency (WR). Fire behavior (surface rate of spread (ROS), fireline intensity (FLI), flame length (FL)) was simulated by BehavePlus 5.0.5 software. Comparisons between burned and unburned areas were done through ANOVA as well as deterministic and stochastic interpolation techniques; multiple correlations among parameters were evaluated by principal factor analysis (PFA) and differences/similarities between areas by principal component analysis (PCA). In both sites, fires were characterized by high severity and determined significant changes to some soil properties. The PFA confirmed the key ecological role played by fire in both sites, with the variability of a four-modeled components mainly explained by fire parameters, although the induced changes on soils were mainly site-specific. The PCA revealed the presence of two main “driving factors”: slope (in Sant'Antioco), which increased the magnitude of ROS and FLI; and soil properties (in Laconi), which mostly affected FL. In both sites, such factors played a direct role in differentiating fire behavior and sites, while they played an indirect role in determining some effects on soil.

In Mediterranean forest ecosystems, spontaneous regeneration presents various problems. Therefore, it is difficult to observe this phenomenon in natural conditions and the areas in which it occurs represent a great opportunity to analyze its dynamics. A case of natural regeneration of Pinus pinea L. has been observed and analyzed in a coastal dune area of Sardinia, where there is an artificial pine forest of about 65 years. Although the study was developed in a small area, the results represent a further step in understanding the dynamics that drive the spontaneous renewal of the domestic pine.

Despite the increasing challenges wildfires are posing around the globe, and the flourishing production of high-quality wildfire scientific knowledge, the ability of fire science to impact knowledge on the ground, for people, society, economy, and the environment, in a way that facilitates change in the current wildfire management system has been limited. We believe that one reason for this limited impact is due to the fragmentation of this scientific knowledge. Therefore, we propose a Translational Wildfire Science (TWFS) as a new field of knowledge that captures the comprehensive dynamics of wildfire events, that provides information relevant, useful, and accessible to practitioners and citizens, and that facilitates the transfer of scientific knowledge into practice. The foundations of TWFS, including the main principles, the overarching characteristics, and the approach of a TWFS scientist, are presented. Finally, the next steps to be undertaken to consolidate TWFS as a new scientific field are identified.

In European mountain regions, forests play an important role in the mitigation of risk due to natural hazards such as landslides, rockfalls, floods and avalanches. Conifer species usually provide a protective effect at higher altitude, while at lower altitudes broadleaf species are dominant. These forests are or were often managed as coppice systems. The high stem density of coppice stands, their rapid growth and the permanence of root systems in the soil can be considered as assets in terms of protective function. However, these considerations are poorly researched and there is generally a lack of studies investigating the suitability of coppice as protection forests. The issue is relevant, considering that many coppice stands in mountain regions have become uneconomic and are now abandoned and overaged. Whether and how to manage these forests stands is a key question for practitioners. In this contribution we analyze the implications of coppice management for slope stability and in particular to mitigate shallow landslides, focusing on root reinforcement, the main mechanism by which vegetation can reinforce slopes. We review available studies concerning root distribution and dynamics in coppice stands to formulate hypotheses about their contribution in terms of root reinforcement. Finally we highlight the lacks of knowledge and the further steps needed to properly evaluate the effectiveness of the coppices in protecting against shallow landslides.

Surface biomass characterization plays a key role in wildfire management. It allows classifying vegetation fuels flammability for fire risk analysis, to define silvicultural prescriptions for fire hazard reduction, to plan prescribed burning, or to model fire behavior and its effects, such as greenhouse gas and pollutant emissions. To facilitate fuel classification and analysis of potential fire behavior and effects in Italy, we harmonized 634 measurements of surface wildland fuels from Alpine, temperate and Mediterranean environments. The dataset provides quantitative data for duff, fine dead fuels and downed woody material, live grasses and shrubs fuel components. Surface fuel data were harmonized by subdividing loads (Mg ha-1) to standard size classes for dead (0-6, 6-25 and 25-75 mm) and live (0-6, 6-25 mm) fuels, collecting percent cover and depth/height (cm) of the various fuel components, and classifying observations into 19 fuelbed categories. To ensure comparability with existing vegetation classification systems, we classified each observation according to the European Fuel Map, the Corine Land Cover classes (level IV), the European Forest Types, and the forest categories of the Italian National Forest Inventory. The dataset and a photo description of each fuelbed category are available as Supplementary material. This dataset is the first step to develop several products at the national scale such as: (i) fuel type classification and mapping; (ii) carbon stock and wildfire emission estimates; (iii) calibration of fuel models for the simulation of fire behavior and effects.

International audience; The most widely used metrics to characterize wildfire regime and estimate the impact of wildfires are total burnt area (BA) and the number of fire events (FE). However, these are insufficient to analyse the threat to society of a new fire regime characterized by a higher occurrence of very large events. To overcome this weakness, we propose the use of a Concentration Index (CIB) which makes it possible to identify spatio‐temporal patterns. The frequency distribution of BA follows a negative exponential distribution almost everywhere, in which a small minority of FE is responsible of the majority of BA. In this article, the spatio‐temporal behaviour of BA is analysed in Western Mediterranean Europe, with particular focus on Portugal, Spain, France and Italy, using data from the European Forest Fire Information System and national wildfire databases. This is the first time that the CI has been applied to wildfire events. This research shows that, in most Mediterranean European countries, the amount of BA is increasingly related with a lower number of fires. The spatio‐temporal distribution of CIB shows high variability in all of the countries analysed in Europe. Portugal and Spain show increasing significant trends of CIB + 7.6% (p‐value = 0.001) and + 1.3% per decade (p‐value = 0.003). Statistically significant correlations for Portugal, Spain and Italy are also found between the annual CIB and several teleconnection indices. The application of the CIB demonstrates its discriminatory ability, which is a key point in detecting vulnerable areas and temporal trends under climate change.

We have recently been made aware by the Forests Editorial Offices of some errors and omissions in the Introduction Section 1 [...]

Forest fires in Algeria are mostly human-caused and result from local social behavior, whether voluntary (arson) or involuntary (negligence). Understanding the reasons why fires start is, therefore, a crucial factor in preventing or reducing their incidence, developing significant prevention efforts and designing specific fire prevention campaigns. The Delphi method is a promising tool for improving knowledge about how fire starts and why, and above all helps reduce the number of fires started by unknown causes, the majority type in Algeria. The Delphi method uses a set of procedures for eliciting and refining the opinions of a panel of experts on a particular subject of interest. This method was used in three case studies, in coastal or inner wilayas (provinces) selected from a highly fire-prone area in north-central Algeria. Results showed the traditional use of fire in agriculture and forestry, in situations related to land use changes and in interpersonal conflicts are the major causes of voluntary fires. For involuntary events (negligence), experts unanimously identified the importance of the restart of fire, caused by fire crews who do not ensure the mopping up of controlled fires (91.49%) and the negligent use of agricultural fires, particularly stubble burning (80.14%). For voluntary fires (arson), results highlight the importance of fires set for land use changes (77.30%), pyromania (67.38%) and honey gathering (62.41%). Illegal dumping and burning of garbage was also mentioned by responders in all study-areas.

One of the most important environmental issues in Europe is the expansion of wildland-urban interfaces (WUIs) and how this trend may affect the occurrence of wildfires. Land use changes, the abandonment of farmland, and reduced grazing has led to an increase in forested areas with an accumulation and continuity of surface fuels available for combustion. Policies based exclusively on extensive fire suppression have become ineffective in different parts of Europe. To reduce the threat of damaging and costly wildfires, European countries must develop integrated fuel management programs. This approach has proven to be one of the most cost-effective for preventing wildfires and reducing economic loss. To this end, we have conducted a cost-effectiveness analysis to estimate how much fuel must be treated to determine fuel load removals with the lowest cost per hectare of unaffected WUIs threatened by wildfires in southern Italy (Apulia region). The analysis was carried out in three stages: (i) simulation of fire behavior in different fuel load reduction and wind direction scenarios; (ii) estimation of WUIs affected by wildfires within the study landscape; and (iii) the application of a cost-effectiveness ratio. Our results highlight the need to provide a method to evaluate the cost-effectiveness of fuel removal given the increasing number and extent of WUIs in the Mediterranean landscape of Europe. Optimizing the cost-effectiveness analysis of fuel removals offers the basis for appropriately assessing wildfire prevention and budgeting financial resources. Further, this method may be readily applied toward allocating any type of intervention in landscape management.

Mediterranean communities have been historically conditioned by fire and have therefore developed adaptive traits. Serotiny is a strategy that increases fire resilience by storing seeds in the canopy, protecting them from heat and delaying their dispersion. Aleppo pine is an important serotinous tree species in the low altitude, near-coastal Mediterranean Basin. Differences in serotinous and non-serotinous cones have been detected previously but in order to resolve a gap in the knowledge on seed adaptation to fire, we focused this study on two fire-prone habitats in southern Italy. Several cones were sampled and opened in an oven at two different temperatures in order to group seeds according to provenance and cone type (serotinous or non-serotinous). The sampled seeds were weighed and their coats were removed. Seed size, embryo diameter and nutritive tissue thickness were recorded. We found that seeds with greater weight and size came from the more humid site and from non-serotinous cones. Also, we observed wax and cutine cells formed a thicker seed coat in seeds from the more humid site using a scanning electron microscope. The scanning electron microscopy/energy dispersive X-ray spectroscopy showed higher Si and Ca concentrations in the covers of serotinous seeds. Seeds from different provenance and cone types have anatomic and morphological differences that confer different properties against heating. This knowledge can improve post-fire management and promote restoration tools.

Il crescente numero di incendi richiede una organizzazione difensiva piu attenta alla prevenzione, affidando un ruolo fondamentale agli strumenti di indagine territoriale, che possono aiutare ad individuare linee di tendenza e concentrazione del fenomeno, a interpretarne la dinamica e le motivazioni e ad impostare efficaci azioni di previsione del rischio. Fondamentale appare l’impiego di tecniche di investigazione che consentono di definire la distribuzione spaziale degli eventi sul territorio, agevolando l’interpretazione di un fenomeno di origine prevalentemente antropica con l’aiuto della conoscenza del problema a livello locale e dell’esperienza degli operatori del settore AIB. Il lavoro affronta aspetti relativi alla distribuzione del fenomeno attraverso il metodo della kernel density e all’applicazione del metodo Delphi per la valutazione delle motivazioni. L’applicazione delle due metodologie di analisi in ambito provinciale ha permesso l’identificazione delle motivazioni principalmente di origine volontaria (ampliamento, apertura o rinnovazione del pascolo a spese del bosco) e involontaria (attivita di ripulitura di incolti, bruciature stoppie, attivita di miglioramento o rinnovazione del pascolo).

Given the multiplicity of products, human activity over the past thousand years has strongly interacted with pine forest distribution. The results of human activity and its impact on the pine forests is a problem that began in the past, when wood and pine ecosystems were not valued, and whose repercussions are still felt today; notably in changes in fire regime, in grazing/browsing intensity, in harvesting, in land use, in plantation activity, in expansion of forest/urban interface, and in secondary urban settlements. Conservation, in this sense, means the maintenance of and the restoration or improvement of the abiotic and biotic features, which form the habitat of a species, as well as controlling activities, which may indirectly result in the deterioration of such habitats. Conservation, therefore, ranges from the conservation of genetic resources in several forms (seed banks, seed forests, conservation in situ of relic populations), to the elimination of human induced disturbances, to the planning of new activities, to the application of proper silvicultural tending and the pursuance of international Conventions, Regulations and Resolutions. The aim of this paper is to emphasise the main legislative tools, which are represented by the array of Conventions, Directives, Regulations and Resolutions concerning the environment and the ecological networks (NATURA 2000, EMERALD, EUNIS).

The dramatic increase of fire hazard in wildland–urban interfaces (WUIs) has required more detailed fuel management programs to preserve ecosystem functions and human settlements. Designing effective fuel treatment strategies allows to achieve goals such as resilient landscapes, fire-adapted communities, and ecosystem response. Therefore, obtaining background information on forest fuel parameters and fuel accumulation patterns has become an important first step in planning fuel management interventions. Site-specific fuel inventory data enhance the accuracy of fuel management planning and help forest managers in fuel management decision-making. We have customized four fuel models for WUIs in southern Italy, starting from forest classes of land-cover use and adopting a hierarchical clustering approach. Furthermore, we provide a prediction of the potential fire behavior of our customized fuel models using FlamMap 5 under different weather conditions. The results suggest that fuel model IIIP (Mediterranean maquis) has the most severe fire potential for the 95th percentile weather conditions and the least severe potential fire behavior for the 85th percentile weather conditions. This study shows that it is possible to create customized fuel models directly from fuel inventory data. This achievement has broad implications for land managers, particularly forest managers of the Mediterranean landscape, an ecosystem that is susceptible not only to wildfires but also to the increasing human population and man-made infrastructures.

Res_eng:Despite enhanced fire suppression efforts the number of fires has increased in Europe and in North Africa, above all in Portugal, and the extinction oriented model of fire control is no more suitable to change the trend. Hence, the need of shifting from a reactive model grounded on a fast and strong reaction, to more pro-active procedures supported by prevention, aimed not only to fuel reduction but also to gradually intervene on the causes of fires. In this perspective, a fair knowledge of man-caused fire outbreak motives is a crucial point. This paper intended to compare and interpret those motives in Portugal, Italy and Algeria obtained through the perception of experts (forest experts and other practitioners). In this research new data was collected in the North Region of Portugal and data already available for Algeria and Italy was commented. The results of the research highlighted great similarities of the main fire causes and motives identified by the experts from the case-studies in the three countries. Fire outbreak motives are not related with deliberate fire setting but, mainly, with the use of fire in rural activities. Fire is a manageable tool that is still needed in many agro-forestry systems. One of the findings of this study pointed out the need to design and develop specific prevention programs able to reduce fire incidence and promote practices more respectful of the tradition and needs of rural communities, often criminalized for their habitudes of using fire as a multipurpose tool. Deliberate fire can represent isolated and sporadic actions however, some of them result from organized and even criminal interests. Finally, this paper argues that improved fire prevention to address the roots of fire problems cannot be achieved without a deep knowledge of the complexity and diversity of the fire outbreak motives.

"\"\\\"Prescribed burning experiences in Italy: an integrated approach to prevent forest fires. Prescribed burning. is used in many geographical areas for multiple and integrated objectives (wildfire prevention, habitat conservation,. grazing management). In Europe the collaboration between researchers and fire professionals has. brought to implement this technique over increasing areas (~104 ha year-1), effectively and efficiently. In Italy. prescribed burning has not been much studied and it is rarely applied. A new interest is recently rising.. Some Regions particularly threatened by wildfires have updated their legislation and set up procedures to. authorize prescribed fire experiments and interventions. From 2004 to 2011 several scientific, operative and. training experiences have been carried out at a regional level (Basilicata, Campania, Friuli Venezia Giulia,. Piemonte, Sardegna, Toscana). The present paper aims to: (i) document and compare these regional programs;. (ii) discuss their frameworks and limitations; (iii) provide information about objectives, prescriptions,. methods and results. The study has involved Universities, Forest Corps, Civil Protection, Municipalities,. Parks and professionals from Italy and other Countries. Interventions have regarded integrated objectives. (fire hazard reduction; habitat conservation; forest and grazing management), and involved several vegetation. types (broadleaved and conifer forests; Mediterranean and Continental shrublands; grasslands). Studies. on fire behaviour and ecology have helped to set prescriptions for specific objectives and environments. Re -. sults have been transferred to professionals through training sessions. Several common elements are outlined:. integrated objectives, multidisciplinary character, training and research products. Ecological questions,. certification to the use of fire, communication to local communities and the proposal of new studies, are. some of the issues outlined in the discussion. The present study is the first review at national level and we. hope it will help to deepen the meaning and limitations of a technique which is an effective tool to prevent. wildfires when integrated in the forest and land planning process.\\\"\""

The current chapter starts by describing the elements of biodiversity in the Mediterranean Basin hotspot. It then describes climate change and fire regime interactions. Geographically restricted forest types with high conservation value such as Abies cephalonica, A. pinsapo, Juniperus macrocarpa, Quercus trojana, Tetraclinis articulata and Pinus leucodermis forests are presented as case studies. These forest hotspots are threatened by changing fire regime either because they lack of any active post-fire regeneration mechanism or because they are exposed to more frequent fires than they used to. Current post-fire management, if any, is presented and commented.

The Mediterranean region accounts the larger proportion of human caused fires in the world (95%) followed by South Asia (90%), South America (85%) and Northeast Asia (80%) (FAO 2007). Socio-economic changes which are occurring in Europe along with global warming result in an augment of fire risk. Systematic and reliable information on fire causes is necessary in order to improve wildland fire management. However, collection of information on forest fire causes and motivations is still quite restricted in most countries around the world. The unknown cause is still too frequent in many wildfire statistics. A promising technique to overcome this shortcoming is the Delphi technique which uses a panel of carefully selected experts to improve the knowledge on fire motivations in a specific area. Understanding more about why people start fires would help to reduce the impacts of deliberate fire lighting. Spatial and temporal analysis of wildland fire occurrence data and the interaction with explanatory geographical variables is a critical part of fire management activities. Geographic Information Systems (GIS) are appropriate tools to create, transform, combine and integrate variables related to fire risk in order to find geographical and analytical relationships which help to discriminate areas where risk factors are most severe in order to adopt the appropriate preventive actions.

Pinus halepensis Mill., a widespread, low elevation conifer common in Mediterranean Basin, shows a dual reproductive strategy: post-fire obligate seeder (from serotinous cones) and an early coloniser (from non-serotinous cones). Release of seeds encased in serotinous cones is induced either by fire (pyriscence, serotiny or bradychory) or by drying (xeriscence). Morphological differences in serotinous and non-serotinous cones in natural populations of P. halepensis in Southeastern Italy were analyzed. Relationships between tree size (diameter class) and serotiny were checked by counting and sampling serotinous and non-serotinous cones. The macro and microscopic characteristics that could affect cones’ opening were measured in sampled cones. Protection against high temperatures offered by wood scales was also evaluated by applying different temperatures and time exposures, and following the inner thermal raise. Results showed that non-serotinous cones had bigger resin ducts and more separate scales. Also it was highlighted that ovuliferous scales of serotinous cones were bigger and thicker. These scales had more lamellated (multilayered) sclereid cells, and were significantly thinner with a shorter lumen diameter. Continuous temperature-monitoring heat tests inside cones showed that temperatures close to the cone axis were rather low, so seed germination was not influenced. Results confirm that serotinous cones are more compact, rigid and consistent than non-serotinous cones. These characteristics explain the lower insulation, seed protection and the ease opening of non-serotinous cones as well. In conclusion, opening mechanism of pinecone scales under the effect of fire or dry conditions seem related to anatomic differences and it provides seeds with an efficient protection against heat.

[1] The main problem encountered when applying remote sensing and geographic information systems techniques for wildfire risk assessment is the necessity to integrate different data sources. The methods applied so far are usually based on regression techniques or on coefficients relying on experts' knowledge. Hence fire managers are seeking an unbiased statistical model able to highlight the multivariate spatial relationships between the predictor variables, yielding understandable output readily accessible to end users. The present research aims to test the capability of classification and regression trees (CART) analysis to assess long-term fire risk at a local scale. The CART analysis is a nonparametric statistical technique which generates decision rules in the form of a binary tree, for a classification or a regression process. A fire-prone study area was selected in the southeast of Italy. Fire ignition points, relative to a 7 year period (1997-2003), were used to derive a fire occurrence map through a kernel density approach. The resulting map was then used as input response variable for the CART analysis with fire danger variables used as predictors. The rules induced by the regression process allowed the definition of different risk levels, expressed as 30 management units, which is useful for producing a fire risk map. The result of the regression process (r = 0.77), the capability of the CART analysis to highlight the hierarchical relationships among the predictor variables, and the improved interpretability of the regression rules represent a possible tool useful for better approaching the problem of assessing and representing fire risk.