Forest fires are a recurring disturbance in Mediterranean ecosystems, but they also impact air quality and public health, particularly given recent trends towards increasingly widespread and extreme fires. This study analyzed six large fires that occurred in Sardinia, Italy, between 2009 and 2021, in order to evaluate their impact on ground-level PM10 concentrations and to investigate the influence of fire size, fuel type, and meteorological conditions. The analysis included data on fire perimeters and land cover, meteorological conditions, smoke plume trajectory simulations using HYSPLIT, satellite imagery, and PM10 concentration measurements from the regional air quality monitoring network. The six case studies differed markedly in terms of burned area, vegetation composition, duration, and weather context. The results showed that the extent of the fire is likely not the most significant factor influencing the increase in PM10 observed in the days following the fires. The most pronounced increases in PM10 concentrations were recorded during the Isili and Montiferru fires, which differed in burned area but were similar in terms of fuel composition, dominated by forest and shrubland vegetation. These factors, together with favorable atmospheric conditions for plume transport and particulate matter deposition, likely contributed to the observed increases in PM10, including exceedances of WHO and national daily limit values. By contrast, Bonorva, Ittiri, and Borore showed limited or no clear accumulation of PM10, despite large burned areas in some cases. These findings suggest that the effects of wildfires on air quality in the Mediterranean region can be influenced by several features, such as meteorological conditions, biomass burned, area burned, severity and intensity of fires. Furthermore, the observed exceedance of WHO thresholds highlights the need to integrate public health considerations into wildfire risk management in the Mediterranean basin.

Fires have been a natural component of Mediterranean ecosystems for centuries, contributing to their ecological balance. However, they also release significant amounts of smoke and various pollutants like carbon monoxide, methane, nitrous oxide, nitrogen oxides, volatile organic compounds, and particulate matter (PM). The emissions not only compromise air quality but also pose a threat to human health, particularly for those with chronic heart and lung diseases. These impacts have been largely studied in the United States and in neighboring countries, while in the Euro-Mediterranean continent the studies available on the patterns of wildfires and fire emissions are more limited. However, the increase in the frequency of large fires recorded in recent years, especially in southern Europe and often close to inhabited centers, urges the scientific community to investigate on the impact of these events on air quality and human health at European level as well.This study examines six large fires (>2000 ha) in Sardinia, Italy, over the past fifteen years, with the main aims to (i) characterize the six forest fires in term of size, fuel, and weather conditions; (ii) estimate the contribution of the six forest fires to environmental PM levels.Meteorological conditions at synoptic scale have been investigated through NCEP Climate Forecast System Reanalysis (CFSR) data with a spatial resolution of 0.5° x 0.5° and maps of 850 hPa temperature and airmasses from WetterZentrale (https://www.wetterzentrale.de/). The impacts on particulate matter on air quality has been evaluated through data obtained from the monitoring stations of the Air quality control network of the Regional Environment Protection Agency of Sardinia (ARPAS). To further investigate the impacts of the fire plumes, the study employs the HYSPLIT (hybrid single-particle Lagrangian integrated trajectory) model developed by NOAA’s Air Resources Laboratory to compute the forward trajectories of air masses. Finally, for selected recent fires, the plume spatial distribution has been investigated and verified using Modis satellite images on board the Aqua satellite as well as the visible Infrared Imaging Radiometer Suite (VIIRS) Corrected Reflectance imagery on board the joint NASA/NOAA Suomi National Polar orbiting Partnership (Suomi NPP) satellite.Preliminary findings reveal varying degrees of correlation between air quality and fire events in the six examined cases. This variability could be attributed to different fuel types, atmospheric conditions, and, to a significant extent, the location and density of air monitoring stations.

A number of works are highlighting the increasing size and severity of large wildfires in the Mediterranean Basin, with cascading effects on post-fire erosion. Direct measurements of post-fire soil erosion, particularly in remote and complex terrain, are time-consuming and expensive and are further challenged by the risk of sudden and intense rainstorms following wildfires at the end of the fire season. In this work, we will present the preliminary results of the post-fire erosion measurements carried out in the Montiferru area (Sardinia, Italy), which was affected by a 13,000 ha wildfire at the end of July 2021. Six sediment fence sites were established a few weeks after the wildfire and prior to rain events in the study area. The fences allowed us to monitor post-fire sediment erosion on two hillslopes, the first mainly characterized by Quercus ilex and Erica arborea (plots 1–3), the second by Arbutus unedo and Quercus ilex (plots 4–6). Each sediment fence, constructed of geotextile silt fence fabric, covered an area of 30 m2 (10 m × 3 m), and was installed on uniform slopes. For both hillslopes, fences were installed adjacent to one another across the tilted terrain. The results obtained during the first months of monitoring will be discussed while considering soil and rainfall characteristics in the study area, slope, and pre- and post-fire vegetation.

Fires are an integral part of Mediterranean ecosystems, where they have played an ecological role for thousands of years [...]

Wildfire simulators represent a fundamental tool for the planning of wildfire prevention operations, the real-time prediction of fire propagation and thus the adoption of appropriate firefighting strategies. In this paper, we provide an example of the application of the Web-based Wildfire Simulator (WWS) on fires that occurred during the 2021 fire season in Sardinia (Italy), and in particular on the Montiferru fire, a large fire that occurred in the central-western area of the island and mainly driven by the wind. The simulator used high-resolution data provided by the WRF meteorological model initialized with both GFS forecasts and ERA5-ECMWF reanalysis. Vegetation characteristics and associated fuel pattern maps were derived from the analysis of recent Sentinel2 satellite data. Fuel moisture data were estimated using weather data predicted by WRF. The evaluation of the model was carried out using the data collected in field and related to the actual fire propagation observed during the various time steps, and to the related firefighting interventions. In addition, the meteorological data recorded by a few meteorological stations located within the simulation domain and the data on fire severity collected in field were analyzed. The model was able to predict the temporal development of fire events with a good accuracy, considering the mean rate of spread and the rate of spread of the different wildfire sectors. Most of the accuracy can be explained by the goodness of the weather forecasts obtained through the use of GFS forecasts and of the fuel model map. The model was able to accurately predict the propagation of the main fire front, while several deviations from the real perimeter were observed with regard to the fire flanks propagation. In conclusion, wildfire simulators represent a useful tool for all phases of fire prevention, for their operational use in real-time, and therefore to provide information for the firefighting.

In this work, we will present the transboundary wildfire simulation system used to analyze fine-scale (100-m resolution) wildfire hazard and exposure in the regions of the Italy–France Maritime cooperation area (Sardinia, Corsica, Tuscany, Liguria and Provence–Alpes–Côte d’Azur), which covers about 93,000 km2 of land. The study area is characterized by a variety of ecological, cultural, anthropic and touristic values that are heavily threatened by wildfires, mostly during the summer season. The wildfire issues in the area are expected to worsen in future years due to a number of contributing factors, including climate change, the abandonment of agrosilvopastoral areas with the resulting increase in fuel load and continuity and the expansion of urban interfaces into fire-prone wildlands. To perform our analysis, among the large set of wildfire spread models available, in the framework of the MED-Star project, we have selected the Minimum Travel Time (MTT) algorithm of Finney (2002) as implemented in FConstMTT. As inputs for our simulations, we produced underlying fuel maps derived from regional land use and forest maps and focused on the historical moisture and weather conditions and patterns associated with the largest wildfires that affected the study area in the last 20 years. The simulation outputs allowed us to characterize spatial variations in wildfire spread and hazard among and within provinces and regions and to identify the most significant hot-spot areas. In addition, we combined the simulated raster data with several explanatory variables and spatial layers (e.g., wildland–anthropic interface maps; provinces; climatic zones; etc.) to characterize exposure levels at different levels. Findings from this work improve regional awareness and knowledge about the spatial dynamics and patterns of wildfire exposure and hazard in the Italy–France Maritime cooperation area.

In Mediterranean agropastoral areas, land abandonment is a key driver of wildfire risk as fuel load and continuity increase. To gain insights into the potential impacts of land abandonment on wildfire risk in fire-prone areas, a fire-spread modeling approach to evaluate the variations in wildfire potential induced by different spatial patterns and percentages of land abandonment was applied. The study was carried out in a 1200 km2 agropastoral area located in north-western Sardinia (Italy) mostly covered by herbaceous fuels. We compared nine land abandonment scenarios, which consisted of the control conditions (NA) and eight scenarios obtained by combining four intensity levels (10, 20, 30, 40%) and two spatial patterns of agropastoral land abandonment. The abandonment scenarios hypothesized a variation in dead fuel load and fuel depth within abandoned polygons with respect to the control conditions. For each abandonment scenario, wildfire hazard and likelihood at the landscape scale was assessed by simulating over 17,000 wildfire seasons using the minimum travel time (MTT) fire spread algorithm. Wildfire simulations replicated the weather conditions associated with the largest fires observed in the study area and were run at 40 m resolution, consistent with the input files. Our results highlighted that growing amounts of land abandonment substantially increased burn probability, high flame length probability and fire size at the landscape level. Considering a given percentage of abandonment, the two spatial patterns of abandonment generated spatial variations in wildfire hazard and likelihood, but at the landscape scale the average values were not significantly different. The average annual area burned increased from about 2400 ha of the control conditions to about 3100 ha with 40% land abandonment. The findings of this work demonstrate that a progressive abandonment of agropastoral lands can lead to severe modifications in potential wildfire spread and behavior in Mediterranean areas, thus promoting the likelihood of large and fast-spreading events. Wildfire spread modeling approaches allow us to estimate the potential risks posed by future wildfires to rural communities, ecosystems and anthropic values in the context of land abandonment, and to adopt and optimize smart prevention and planning strategies to mitigate these threats.

Fire propagation is mainly influenced by three elements: slope of the terrain, vegetation, and wind [...]

Abstract. An NGS-based taxonomic analysis was carried out on airborne bacteria sampled at ground level in two periods (May and September) and two opposite localities on the North-South axis of the Sardinia Island. Located in a central position of the Mediterranean basin, Sardinia constitutes a suitable outpost to reveal possible immigration of bacterial taxa during transcontinental particle discharge between Africa and Europe. With the aim of verifying relative effects of dust outbreaks, sampling period and sampling site, on the airborne bacterial community composition, we compared air collected during dust-carrying meteorological events to that coming from wind regimes not associated to long-distance particle lifting. Results indicated that: (a) a higher microbial diversity (118 orders vs 65) and increased community evenness were observed in the campaign carried out in September in comparison to the one in May, irrespective of the place of collection and of the presence or absence of dust outbreaks. (b) During the period of standard wind regimes without transcontinental outbreaks a synchronous, concerted succession of bacterial communities across distant locations of the same island, accompanied as mentioned by a parallel rise in bacterial diversity and community evenness appears to have occurred. (c) changes in wind provenance could transiently change community composition in the locality placed on the coast facing the incoming wind, but not in the one located at the opposite side of the island; for this reason the community changes brought from dust outbreaks of African origin are observed only in the sampling station exposed to south; (d) the same winds, once proceeding over land appear to uplift bacteria belonging to a common core already present over the region, which dilute or replace those that were associated with the air coming from the sea or conveyed by the dust particulate, explaining the two prior points. (e) the hierarchy of the variables tested in determining bacterial assemblages composition results: sampling period >> ongoing meteorological events > sampling location within the island.

Citizen science is the scientific research that involves the participation of the public assisting professional scientists. This typically occurs in helping to data collection and/or data analysis, and an increasingly popular use of citizen science is the collection of phenological data, like wildflowers blooming in summer or leaves changing color in fall. Studying the life cycles of plants (phenology) reveals some consequences of climate change.The PCTO (Percorsi per le Competenze Trasversali e per l'Orientamento) is a school-work alternation program and represent an innovative teaching method, introduced in 2015 by the Italian Ministry of Education, University and Research. This program, through practical experience, helps to consolidate the knowledge acquired at school and to enrich the student training. The school-work alternation is compulsory for all the students of the last three years of high school (13-17 years age). This program is a cultural change that incorporates good European practices, aimed at creating a synergy between school and work in order to encourage students to follow program learning inside of a public/private company.The National Research Council of Italy is a partner of this program and each year students from high school are involved in technical and research activities. During the years 2015-2019, the Institute for the BioEconomy of Sassari, offered a School-Work learning program dedicated exclusively to Phenological and Pollen monitoring to groups of students of High School. While they employed their skills at work, they learnt to implement the specific protocols of a scientific project. These experiences increased their awareness of the essential role they can play by acquiring new knowledge of the environment and skills through scientific tools of citizen science. In this paper, results of the Phenological and Pollen monitoring program held at IBE-CNR Sassari are illustrated.In the future, citizen scientists can provide reliable observations when following scientific methods and standardized protocols. Phenological monitoring programs based on volunteers support will become increasingly important in providing open‐access, standardized data sets capable of supporting the process of answering ecological and global change questions.

Wildfires represent a major threat to Mediterranean ecosystems and are responsible for relevant impacts to environmental, economic and social values. In the period 2010-2016, the cross-border Interreg Italy-France Maritime territory, which includes Sardinia, Corsica, Tuscany, Liguria and PACA Regions, had about 20,000 wildfire ignitions and a total burned area of about 122,000 ha. In the face of social and environmental conditions and risks of the Maritime Regions, strengthening and developing innovative common guidelines and systems of wildfire management, from the monitoring and forecast to suppression, can provide more effective solutions to the wildfire problem, and can help strengthen cross-border cooperation in case of days with high risk. This work is devoted to introduce the MED-Star project, and to describe his main activities and results, with a focus on the tasks and activities coordinated by the National Research Council of Italy, Institute of BioEconomy (CNR-IBE) of Sassari. MED-Star is a 3-years strategic project supported by the Interreg Italy-France Maritime Program 2014-2020, which is co-financed by the European Regional Development Fund (ERDF). MED-Star is closely linked to 4 joint simple projects (Intermed; Med-Coopfire; Med-Foreste; Med-PSS), which mainly focus on investments in small infrastructures for wildfire risk prevention and support to wildfire suppression operations. The MED-Star project aims to share and discuss fire management policies and the most advanced strategies that can reduce the risk associated with wildfires, also through the combination of joint action plans and pilot / demonstration actions. The partnerships of MED-Star and the related 4 simple projects include the main actors competent at the administrative, technical and scientific level on the wildfire topic in the Maritime area of cooperation, and are able to meet the abovementioned challenges, contributing to 1) the reduction of wildfire risk in the five Regions involved, 2) the definition of strategic and operational solutions, 3) the implementation of operational actions and investments for wildfire prevention, monitoring, forecast and suppression, and 4) the strengthening of joint early warning and risk monitoring systems.

High severity wildfires can have many negative impacts on ecosystems. In this work, we coupled wildfire spread and erosion prediction modelling to evaluate the effects of fuel reduction treatments in preventing soil runoff in Mediterranean ecosystems. The study was carried out in a 68,000-ha forest area located in Northern Sardinia, Italy. We treated 15% of the study area, and compared no-treatment conditions vs alternative strategic fuel treatments. We estimated pre- and post-treatment fire behaviour by using the Minimum Travel Time (MTT) fire spread algorithm. For each fuel treatment scenario, we simulated 25,000 wildfires replicating the historic weather conditions associated with severe wildfires in the area. Sediment delivery was then estimated using the Erosion Risk Management Tool (ERMiT). Our results showed how post-fire sediment delivery varied among and within the fuel treatment scenarios tested. The treatments realized nearby roads were the most efficient. We also evaluated the effects of other factors such as exceedance probability, time since fire, slope, fire severity and vegetation type on post-fire sediment delivery. This work provides a quantitative assessment approach to inform and optimize proactive risk management activities aimed at reducing post-fire erosion in Mediterranean areas.

Airborne pollen data are an important source of information on flowering phenology, because they record the response of plants surrounding the sampling station, rather than the responses of individual plants, as with direct phenological observation. Plant phenology represents a good indicator of vegetation responses to long-term variation to temperatures. Furthermore, several studies have evidenced that aerobiological data series and pollen season are often strongly correlated to climate change. This research aims to analyze airborne pollen data of Poaceae and Fagaceae measured from 1986 to 2008 in a urban area of northern Sardinia (Italy) and to investigate the trends in these data and their relationship with meteorological parameters using time series analysis. The aerobiological monitoring station was located in the center of the city very close to a public garden, and it is part of both the Italian and the European - A.I.A. Aeroallergen monitoring Network. Meteorological data were recorded during the same period by an automatic weather station. The following parameters were calculated for each pollen: start, end and duration of pollen season, date of peak pollen concentration, number of days from the beginning of the season to the peak, annual pollen index (API), percentage distribution of API and maximum daily concentration. The correlation between meteorological variables and the different characteristics of pollen seasons was analyzed using Spearman’s correlation tests. A linear regression model was used for the trend analysis of the API of airborne pollen spread of the two family from 1986 to 2008.

Wildfires are known to change post-fire watershed conditions such that hillslopes can become prone to increased erosion and sediment delivery. In this work, we coupled wildfire spread and erosion prediction modelling to assess the benefits of fuel reduction treatments in preventing soil runoff. The study was conducted in a 68000-ha forest area located in Sardinia, Italy. We compared no-treatment conditions v. alternative strategic fuel treatments performed in 15% of the area. Fire behaviour before and after treatments was estimated by simulating 25000 wildfires for each condition using the minimum travel time fire-spread algorithm. The fire simulations replicated historic conditions associated with severe wildfires in the study area. Sediment delivery was then estimated using the Erosion Risk Management Tool (ERMiT). Our results showed how post-fire sediment delivery varied among and within fuel treatment scenarios. The most efficient treatment alternative was that implemented near the road network. We also evaluated other factors such as exceedance probability, time since fire, slope, fire severity and vegetation type on post-fire sediment delivery. This work provides a quantitative assessment approach to inform and optimise proactive risk management activities intended to reduce post-fire erosion.

Dust particles lifting and discharge from Africa to Europe is a recurring phenomenon linked to air circulation conditions. The possibility that microorganisms are conveyed across distances entails important consequences in terms of biosafety and pathogens spread. Using culture independent DNA-based analyses via next generation sequencing of the 16 S genes from the airborne metagenome, the atmospheric microbial community was characterized and the hypothesis was tested that shifts in species diversity could be recorded in relation to dust discharge. As sampling ground the island of Sardinia was chosen, being an ideal cornerstone within the Mediterranean and a crossroad of wind circulation amidst Europe and Africa. Samples were collected in two opposite coastal sites and in two different weather conditions comparing dust-conveying winds from Africa with a control situation with winds from Europe. A major conserved core microbiome was evidenced but increases in species richness and presence of specific taxa were nevertheless observed in relation to each wind regime. Taxa which can feature strains with clinical implications were also detected. The approach is reported as a recommended model monitoring procedure for early warning alerts in frameworks of biosafety against natural spread of clinical microbiota across countries as well as to prevent bacteriological warfare.