Fire behaviour simulation in Mediterranean maquis using FARSITE (fire area simulator)

In the last two decades several simulation systems were developed to provide information about temporal and spatial variations of fire spread and behaviour. FARSITE (Fire Area Simulator), one of the most common simulators, is a spatially and temporally explicit fire simulation system. The simulator is based on Rothermel's fire spread model, and describes the fire spread and behaviour as a function of relationships among fuels, topography and weather conditions. The use of FARSITE on areas different from those where the simulator was originally developed requires a local calibration in order to produce reliable results. This is particularly true for the Mediterranean ecosystems, where plant communities are characterized by high specific and structural heterogeneity and complexity, determined by the interaction of sub-arid Mediterranean climate and human factors. Therefore, to perform FARSITE calibration, the choice of the appropriate standard fuel models or the development of specific custom fuel models are required. In addition, the capabilities of FARSITE simulator can be affected by other environmental characteristics, as complex steep terrains with the resulting high spatial and temporal variability of wind speed and direction. In this work, FARSITE was employed to simulate spread and behaviour of four real fires occurred in North Sardinia during 2003, 2004 and 2006 summer seasons. The effect of fuel models, weather conditions and topography on the accuracy of FARSITE simulations was evaluated in order to assess the capabilities of the simulator in accurately forecasting the fire spread and behaviour in areas covered by Mediterranean maquis. A custom fuel model, designed and developed by our working group for maquis, provided realistic values of simulated fire behaviour. Improvements on the accuracy of both fire spread and behaviour were also obtained using raster maps of wind speed and direction. The results confirm that the use of both accurate wind field data and appropriate custom fuel models is crucial to obtain accurate simulations of fire behaviour occurring on Mediterranean vegetation during the drought season, when most wildfires occur

A fire modeling approach to assess wildfire exposure of valued resources in central Navarra, Spain

Wildfires are a growing threat to socio-economic and natural resources in the wildland-rural-urban intermix in central Navarra (Spain), where recent fast-spreading and spotting short fire events have overwhelmed suppression capabilities. A fire simulation modeling approach based on the minimum travel time (MTT) algorithm was used to analyze the wildfire exposure of highly valued resources and assets (HVRAs) in a 28,000 ha area. We replicated 30,000 fires at fine resolution (20 m), based on wildfire season and recent fire weather and moisture conditions, historical ignition patterns and spatially-explicit canopy fuels derived from low-density airborne Light Detection and Ranging (LiDAR). Detailed maps of simulated fire likelihood, fire intensity and fire size were used to assess spatial patterns of HVRA exposure to fire and to analyze large fire initiation and spread through source-sink ratio and fire potential index. Crown fire activity was estimated and used to identify potential spotting-emission hazardous stands. The results revealed considerable variation in fire risk causative factors among and within HVRAs. Exposure levels across HVRAs were mainly related to the combined effects of anthropic ignition locations, fuels, topography and weather conditions. We discuss the potential of fire management strategies such as prioritizing mitigation treatment and fire ignition prevention monitoring, informed by fine-scale geospatial quantitative risk assessment outcome

High-level expression of a recombinant active microbial transglutaminase in Escherichia coli

Background: Bacterial transglutaminases are increasingly required as industrial reagents for in vitro modification of proteins in different fields such as in food processing as well as for enzymatic site-specific covalent conjugation of therapeutic proteins to polyethylene glycol to get derivatives with improved clinical performances. In this work we studied the production in Escherichia coli of a recombinant transglutaminase from Streptomyces mobaraensis (microbial transglutaminase or MTGase) as enzymatically active chimeric forms using different expression systems under the control of both lac promoter or thermoinducible phage lambda promoter. Results: Thermoinducible and constitutive expression vectors were constructed expressing Met-MTGase with chimeric LacZ 1-8 PNP 1–20 or LacZ 1–8 fusion protein under different promoters. After transformed in competent Escherichia coli K12 strains were fermented in batch and fed-bach mode in different mediums in order to select the best conditions of expression. The two most performing fusion protein systems namely short thermoinducible LacZ 1–8 Met-MTGase from NP668/1 and long constitutive LacZ 1-8 PNP 1–20 Met-MTGase from NP650/1 has been chosen to compare both efficiency of expression and biochemical qualities of the product. Proteins were extracted, purified to homogeneity and verified as a single peak obtained in RP-HPLC. The LacZ 1-8 PNP 1–20 Met-MTGase fusion protein purified from NP650/1 exhibited an activity of 15 U/mg compared to 24 U/mg for the shorter fusion protein purified from NP668/1 cell strain. Conclusions: Combining the experimental data on expression levels and specific activities of purified MTGase fusion proteins, the chimeric LacZ 1-8 Met-MTGase, which displays an enzymatic activity comparable to the wild-type enzyme, was selected as a candidate for producing microbial transglutaminase for industrial applications.Pubblicat

Spatio‐Temporal Domains of Wildfire‐Prone Teleconnection Patterns in the Western Mediterranean Basin

This work explores the main climate teleconnections influencing the Western Mediterranean Basin to outline homogeneous fire-prone weather domains combining cross-correlation time series and cluster analysis. We found a zonal effect of the Scandinavian pattern over the entire region with an interesting alternation of phases from positive during winter-spring (increased rainfall leading to fuel accumulation) to negative (dry conditions) modes during summer controlling burned area and fire size. The NAO dominates the number of fires over the Iberian Peninsula (IP) while the Western Mediterranean Oscillation pattern modulates fire activity over the Mediterranean coast in the IP (linked to westerly winds), Southern France, Corsica and Sardinia (rainfall regulation). These distinctive influence traits resulted in 3 different domains splitting the IP into a Mediterranean rim along the coast (from southern Spain to southwestern France) and an inland and western region (Portugal plus western Spain); and a third in southeastern France, Corsica and Sardinia

Fostering carbon credits to finance wildfire risk reduction forest management in Mediterranean landscapes

Despite the need for preserving the carbon pools in fire-prone southern European landscapes, emission reductions from wildfire risk mitigation are still poorly understood. In this study, we estimated expected carbon emissions and carbon credits from fuel management projects ongoing in Catalonia (Spain). The planning areas encompass about 1000 km(2) and represent diverse fire regimes and Mediterranean forest ecosystems. We first modeled the burn probability assuming extreme weather conditions and historical fire ignition patterns. Stand-level wildfire exposure was then coupled with fuel consumption estimates to assess expected carbon emissions. Finally, we estimated treatment cost-efficiency and carbon credits for each fuel management plan. Landscape-scale average emissions ranged between 0.003 and 0.070 T CO2 year(-1) ha(-1). Fuel treatments in high emission hotspots attained reductions beyond 0.06 T CO2 year(-1) per treated ha. Thus, implementing carbon credits could potentially finance up to 14% of the treatment implementation costs in high emission areas. We discuss how stand conditions, fire regimes, and treatment costs determine the treatment cost-efficiency and long-term carbon-sink capacity. Our work may serve as a preliminary step for developing a carbon-credit market and subsidizing wildfire risk management programs in low-revenue Mediterranean forest systems prone to extreme wildfires.This study was funded by the LIFE CLIMARK Project (LIFE16 CCM/ES/000065), and the Ministerio de Economia y Competitividad. Juan de la Cierva Formacion research fellows FJCI-2016-31090 and FIJCI-2016-30049)

Incendi ed ecosistemi mediterranei: valutazione degli impatti in regime di cambiamento climatico

In Europa, in particolare nella parte meridionale, ogni anno si registrano mediamente 60.000 incendi, con una superficie complessiva percorsa dal fuoco di circa 600.000 ettari. Negli ultimi anni si è sviluppato un interessante dibattito sui fattori che guidano il regime degli incendi in queste aree. Le ricerche più recenti, supportate dalla statistica, confermano il ruolo guida del clima e della meteorologia, strettamente condizionato dall’uso del suolo e con diverse caratteristiche a seconda della regione. In condizioni di cambiamenti climatici e socioeconomici, quali quelle attuali, è logico pensare che anche il regime degli incendi subisca importanti influenze, a seguito delle modifiche del clima e dell’uso del suolo

Wildfire spread, hazard and exposure metric raster grids for central Catalonia

We provide 40 m resolution wildfire spread, hazard and exposure metric raster grids for the 0.13 million ha fire-prone Bages County in central Catalonia (northeastern Spain) corresponding to node influence grid (NIG), crown fraction burned (CFB) and fire transmission to residential houses (TR). Fire spread and behavior data (NIG, CFB and fire perimeters) were generated with fire simulation modeling considering wildfire season extreme fire weather conditions (97th percentile). Moreover, CFB was also generated for prescribed fire (Rx) mild weather conditions. The TR smoothed grid was obtained with a geospatial analysis considering large fire perimeters and individual residential structures located within the study area. We made these raster grids available to assist in the optimization of wildfire risk management plans within the study area and to help mitigate potential losses from catastrophic events. (C) 2018 The Authors. Published by Elsevier Inc

Assessing cross-boundary wildfire hazard, transmission, and exposure to communities in the Italy-France Maritime cooperation area

The growing threats posed by wildfires in Southern Europe are calling for the development of comprehensive and sound management and risk assessment strategies. In this work, we present the application of wildfire simulation modeling based on the minimum travel time (MTT) algorithm to assess fine-scale (100-m resolution) wildfire hazard, transmission, and exposure to communities in the Italy-France Maritime cooperation area (Sardinia, Corsica, Tuscany, Liguria and Provence-Alpes-Côte d’Azur), which cover about 72,000 km2 of land. We simulated thousands of wildfires considering the current landscape and characterized and measured fine-scale wildfire risk factors and profiles by taking into account historical fire regimes, fuels, winds and fuel moisture conditions associated with the occurrence of the largest wildfires (>100 ha) that affected the study area in the last 20 years. Individual fires were simulated at 100-m resolution, consistent with the input files. Modeled annual burn probability and ignition probability revealed that Sardinia was the Region most affected by wildfires. The wildfire simulation outputs were then combined with main land uses and building footprint locations to characterize wildfire transmission and exposure to communities, and were summarized for main vegetation types and Regions. This study presents a cross-boundary and standardized approach based on wildfire spread modeling to analyze and quantify wildfire risk profiles in Southern Europe. The stochastic wildfire modeling systems we implemented used harmonized sets of data for a vast, fire-prone Mediterranean area, where previous similar studies were conducted at coarser resolutions and covered lower extent of lands. The approach presented in this work can be used as a reference pillar for the development and implementation of a common wildfire risk monitoring, management, and governance plan in the study area. The methods and findings of this study can be replicated in neighboring Mediterranean and other regions threatened by wildfires