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Title: D3.1-2a Review of knowledge gaps and proposal for fuel data collection and test runs /
Language: English
Description: A review of the different aspects of fuel moisture research was conducted. The following knowledge (research) gaps can be identified: (a) The horizontal spatial variability of dead fuel moisture in relation to vegetation (e.g., stand structure, crown closure, stem density, litter and duff depth, etc.) and topographic characteristics (aspect, slope, soil depth and type, etc.) needs to be measured and modelled in the field. (b) The temporal (diurnal and seasonal) variation in dead and live fuel moisture content as related to changes in meteorological parameters (air relative humidity and temperature, insolation and cloudiness, wind speed and duration, etc) needs to be measured in the field for all the dominant Mediterranean fuel types at the species level, to the extent possible. For fire-stricken geographical regions of the Mediterranean Basin, extensive data bases of seasonal fuel moisture data per species or fuel type must be created and, subsequently, converted through statistical analysis to empirical models of fuel moisture prediction, refined for every species or fuel complex. (c) Equilibrium moisture content (EMC) sorption (adsorption and desorption) curves of dead fuels as a function of air relative humidity and temperature need to be created for the fuels of all the dominant species. (d) The fuel moisture timelag (TL) concept needs to be reassessed and measured in dead fuels from different species in relation to the fuel moisture sorption phase (adsorption or desorption), in order to account for the moisture hysteretic effects of dead fuels during the wetting or drying process. (e) A physical model that predicts canopy (crown) live fuel moisture content variations in terms of stand and tree phenological and physiological characteristics and soil water balance has to be formulated. (f) A comparison between actual measurements of dead fuel moisture with the moisture content of fuel analogues (i.e., fuel moisture sticks) is necessary in order to validate the precision of the analogues in fuel moisture assessment. (g) The relationship between dead and live fuel moisture and drought (prolonged period of high temperatures and low air and soil humidity) needs to be further investigated, and in particular, the response of shrub and tree species moisture content to drought. The use of the newly formed SPI (Standard Precipitation Index) drought index might be useful in the correlation with fuel moisture, in addition to the traditionally used KBDI and Palmer indexes. In view of the expected global warming and climatic change, this research aspect of fuel moisture could be very significant in the future. (h) The moisture of extinction (ME) of dead and live fuels must be measured in the field (in situ) with a long series of ignition experiments in different fuel types and, subsequently, correlated with the existing fuel moisture content and meteorological parameters in the field, into regression and probabilistic models. ME values of the most significant Mediterranean fuel types must be measured in the laboratory and in the field. (i) The condensation (water vapour that originates from the atmosphere in the form of dew on the surface of dead fuels) and the latent heat of vaporisation of free water from the fuel particle surface are two terms that are currently neglected and must be taken into account in future physical models of dead fuel moisture content. (j) The optimal temporal (time) step for monitoring vegetation moisture content (greenness) via satellite imagery needs to be determined in dead and live Mediterranean fuel complexes.
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Title: Deliverable 3.1-3 Dead fuel moisture prediction: First results /
Language: English
Description: The Deliverable D3.1-3 (Dead fuel moisture prediction: First results) is included in the Activity 1 (Fuel moisture content prediction) of the Work package 3.1 (Prediction of ignition and fuel flammability and temporal variation of fuel moisture). The aim of Activity 1 is to develop empirical models of dead fuel moisture. There are two posibilities in order to construct this kind of models: directly from atmospheric variables or adapting existing models. Many studies of the applicability of existing dead fuel moisture prediction models to different species, fuels and situations have been published. Some of them are (in chronological order): Hough and Albini (1978); Loomis and Main (1980); Harrington (1982); Fosberg et al. (1981); Simard and Main (1982); Simard et al. (1984); Rothermel et al. (1986); Vega and Casal (1986); Burgan (1987); Hatton et al. (1988); Viney and Hatton (1989, 1990); Pech (1989); Hartford and Rothermel (1991); Viegas et al. (1992); Pook (1993); Marsden-Smedley and Catchpole (2001); Beck and Armitage (2004); Wotton et al. (2005); de Groot et al. (2005), and Slijepcevic and Anderson (2006). Several of these studies also include new empirical prediction models or calibrate existing models to specific conditions. Studies on fuel moisture variation in relation to weather have also been conducted, e.g. Pook and Gill (1993) and Saglam et al. (2006). The published studies vary in relation to the type of model (empirical, semiphysical or both), species and type of fuel considered, the experimental location (field or “ex situ”), the kind of sample (destructive or non destructive), the type of prediction (daily or diurnal) and the statistical analyses used (Ruiz 2005). In this document empirical models fitted from atmospheric variables are presented. The models must be considered as preliminary because new moisture content data are currently being collected in the PARADOX framework. Also, several experiments that currently are being conducted are described and some first fuel moisture data results and preliminary conclusions presented. Information, data analyses, results and conclusions have been provided by AUTH (University of Thessaloniki), FFPD-FRI (Forest Research Institute of Warsaw), INIACIFOR (Instituto Nacional de Investigación y Tecnologia Agraria y Alimentaria of Madrid) and XG-CIFAL (Centro de Investigaciones Forestales y Ambientales de Lourizán, Xunta de Galicia). In some cases measurements and data analyses were completely conducted within the context of the FIRE PARADOX Project. In other ones evaluation and analysis of previous data were carried out in the framework of the project. Different pine species, in accordance with forest stands present in the involved countries, are considered. In relation with the type of fuel, all partners have worked with litter. Aditionally, some studies include duff, 1-hr and 10-hr dead surface fuels or aerial dead fine fuels. Destructive samples were collected from field experimental plots where the different sources of fuel moisture are present. One study was conduced in a meteorological instrument shelter where fuel moisture is only controlled by the vapour exchange with the atmosphere. In this experiment non destructive samples were used. Two kinds of fuel moisture observations were included by the partners in order to achieve two different predictions: daily minimum moisture contents and hourly values.
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Title: D3.1-4 Fire occurrence: relationships with fuel moisture content and remotely-sensed plant phenology data: First results /
Language: English
Description: Sardinia is one of the most fire-prone regions of Italy. The high incidence of fires in Sardinia constitutes a problem in terms of damages and resources management, consequently, for provisional and operational planning, it’s very important to know the wildfire regime characteristics and their linkage with the determinant factors. The study of the relationship between the spatio-temporal distribution characteristics of wildfires and the remote-sensed symphenological variables highlighted the role of temporal NDVI signal as a reliable tool for analyzing ecological processes, going beyond the biophysical significance of single-date NDVI values as proxies to photsyntetic activity. The results obtained show that the simultaneous ordering of symphenological variables and fire regime characteristics, based on the spatial distribution of PNV, is consistent with a climatic control that acts on both phenomena. In an evolving landscape, knowing that the wildfires regime is strictly determined by potential natural vegetation phenology can be helpful for monitoring and predicting fires behaviour under changing climatic scenario. Finally, by providing a phytogeographical framework for characterizing fires, the PNV map can be considered a valuable tool for applying research results to fire management policies, since it takes properly into account the underlying determinant factors.
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Title: D3.1-5 Probability of ignition modelling in forest fuels – First results /
Language: English
Description: Following a similar approach to previous research, and aiming to cover gaps in the literature on ignition, especially in regard to Mediterranean conditions, the present study focuses on the following: (1) To evaluate the threshold of fuel moisture content that allows a fire to start. A range of fuel types (pine needles, grass and Quercus coccifera leaves) are examined, as are different ignition sources (kitchen matches, cigarettes, machinery sparks and electrical discharge), with the presence/absence of wind in order to determine the probability of ignition of selected natural dead fuels (MAICh); and (2) To measure the probability of ignition of annual live herbaceous fuels, at various moisture contents, in the field (AUTh). Fuel moisture content (FMC) is used as the main predictor variable throughout these experiments because it has a major effect on fuel ignitability, is easily altered and can be accurately measured. Only the first results of the study are presented within this deliverable: (1) Probability of ignition of pine needles (Pinus halepensis) with kitchen matches and cigarettes as ignition sources conducted in the wind tunnel of MAICh. (2) Probability of ignition of grass (Hyparrhenia hirta) with kitchen matches as an ignition source conducted in the wind tunnel of MAICh. (3) Some preliminary test of pine needles with machinery sparks as well as grass with cigarettes conducted in the wind tunnel of MAICh. (4) Fuel moisture extinction in live annual herbaceous plants (Avena barbata) in the field (AUTh). The final results will be presented within deliverable D 3.1-10 due in month 46 of the project.
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Title: D3.1-6 Empirical modelling of fuel flammability and initial fire propagation: First results /
Language: English
Description: Fuel flammability, that is “the relative ease with which a substance ignites and sustains combustion” (according to the Wildland Fire Management Terminology, FAO 1986) is closely related to the initial phase of fire propagation. Therefore, is an essential component of fuel hazard and fire risk assessment, that are relevant parts of fire management planning (Dimitrakopoulos 2001). In this frame, the objective of Activity 3.1.5 of FIRE PARADOX is to construct empirical models linking fuel bed flammability to stand and fuel characteristics. Two FP Partners are involved in this activity: P07 (INIA-CIFOR) and P15 (CEMAGREF) that have worked on different European ecosystems. CEMAGREF has sampled fuel beds in relation to fuel models that were studied within WP3.4, and has assessed the effect of variables related to fuel beds, stand characteristics, type of ignition source and wind speed on flammability parameters. Flammability experiments were conducted on fuel beds collected in three major ecosystems or environments that are typical of the French Mediterranean area of Provence: the forest ecosystems and fuel types on acidic (Maures area) and calcareous soils, and the road-forest interfaces (Calcareous Provence area). INIA-CIFOR has conducted flammability tests on fine dead fuel beds resulting of mechanical treatments for wildfire hazard reduction in shrublands, assessing the effect of variables related to fuel beds, types of treatment and types of ignition source/wind speed on flammability parameters. Fuel beds were collected in shrubland experimental plots located in Galicia (NW of Spain) where two types of treatments for wildfire hazard reduction, brush out and crushing, were carried out by Partner P10 (XG-CIFAL). This deliverable presents the first results of the conducted studies.
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Title: D3.1-10 Fire occurence: relationships with fuel moisture content and remotely-sensed plant phenology data: final results (merged with D3.1-9) /
Language: English
Description: Fire is a basic ecological factor that contributes to determine vegetation diversity and dynamics in time and space. Fuel characteristics play an essential role in fire ignition and propagation; at the landscape scale fuel availability and flammability are closely related to the vegetation phenology that directly affects wildfire pattern in time and space. In this view, the annual NDVI profiles derived from high temporal resolution satellites, like SPOT Vegetation, represent an effective tool for monitoring the coarse-scale vegetation seasonal timing. The objective of this study thus consists in quantifying the explanatory power of multitemporal NDVI profiles on the fire regime characteristics of the potential natural vegetation (PNV) types of Sardinia (Italy) over a five-year period (2000-2004). The results obtained show a good association between the NDVI temporal dynamics of the PNV of Sardinia and the corresponding fire regime characteristics, emphasizing the role of the bioclimatic timing of the vegetation in controlling the coarse-scale wildfire spatio-temporal distribution of Sardinia. By providing a sound phytogeographical framework for describing different wildfire regimes, PNV maps can thus be considered helpful cartographic documents for fire management strategies at the landscape scale.
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Title: Deliverable D3.1-12 Empirical modelling of fuel flammability and initial fuel propagation, including determination of fuel moisture threshold for fire ignition /
Language: English
Description: This report sums up the fuel flammability experiments (WP 3.1) dedicated to the determination of the thresholds of fuel moisture for fire ignition, and to the assessment of the ignition probability for different dead (i.e. litter) forest fuels in Greece, Spain, Argentina, and France. The probability of ignition has been modelled in for forest fuels through laboratory fires (Cemagref, INIA-CIFOR, MAICh, AUTH and CIEFAP), using different sources of ignitions and different environmental conditions (i.e. nul wind versus windy conditions). The sources of ignition were glowing, flaming, or sparks. The wind was controlled and set as nul or strong. Fuels were chosen as representative of the main natural (e.g. dead leaves and litter duff) and modified (e.g. pine plantations, residuals of fuel treatments) ecosystems of each country. As the main factor controlling ignition, fuel moisture content (FMC) was controlled experimentally along a wide range (generally 5 to more than 50%). The main findings are: (i) the importance of the combination of the source of ignition, the wind speed and the fuel type to assess the ignition. It has been proved that ignition can vary strongly according to this ‘triangle’, with some sources of ignition being especially efficient for some fuel types, and the complex influence of wind that may increase or decrease the ignition success; (ii) the establishment of community- or species-specific logistic models of ignition versus FMC (see Figure below); (iii) the subsequent determination of fuel moisture of extinction for most fuels studied.
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Title: D3.1-8 Dead fuel moisture modelling and validation /
Language: English
Description: This report presents the final results of researches developed about dead fuel moisture prediction, where empirical dead moisture content models fitted from atmospheric variables were analysed for: Pinus halepensis in Greece, Pinus sylvestris in Poland, and Pinus pinea, P. pinaster and P. radiata in Spain. Several types of fuels were considered: litter, duff and suspended needles. Moreover, an evaluation of the capability of different existing models to predict dead fuel moisture content in the above pine species and Eucalyptus globulus in Spain, and Nothofagus antarctica and Astrocedrus chilensis in Argentina was carried out. In general terms, FWI codes and the Sneeuwjagt and Peet values, adequately reflected the pattern of variation of fuel moisture of litter and duff. Still, the estimates of these models did not show sufficient accuracy to be used directly as predictors of the dead fuel moisture content. In periods not affected by precipitation, simpler vapour exchange models appeared to be suitable for dead fuel moisture content predictions.
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Title: D3.1-1 Review of existing databases for fuel moisture and fuel bed characteristics /
Language: English
Description: Fuel moisture, that is "the moisture percentage of fuel, usually measured by oven-drying a sample and calculating the ratio of dry and moist samples" (according to the EUFireLab Glossary, D-02-01 "Methods for wildland fuel description and modelling: A state of the art") is a critical parameter that affects fire ignition, fire behaviour as well as the impacts of fire. Fuel moisture content is a necessary input for all existing physical, semi-physical and empirical fire behaviour prediction models. In addition, fuel moisture content is a main component of most fire danger rating systems. From the operational point of view, fuel moisture content estimates are also required for prescribed burning (planning and use) and for suppression activities. On the other hand, the characterization of fuel beds, defined as "individual fuel particles organized in defined proportions and structural configurations" (EUFireLab Glossary, D-02-01), has also been pointed out as one of the keys for the assessment of potential fire behaviour and effects, related with both wildland fire prevention and fighting. Therefore, fire scientists as well as fire managers require specific information concerning fuel moisture content and fuel bed characteristics, as it has also been pointed out in Fire Paradox D3.3-1. In this frame, the aim of this deliverable (3.1-1) is to give an overview on existing databases for fuel moisture and fuel bed characterization. To achieve this goal, a search was conducted through Internet, EuFireLab documentation and other literature, and a questionnaire requesting information on the databases for fuel moisture or fuel bed characterization was sent to all members of the Fire Paradox Module 3. A total of five positive answers (XG-CIFAL, Cemagref, University of Thessaloniki, Forest Research Institute of Warsaw and University of Edinburgh) was received.
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Title: D4.2-3-36 Fire flammability of forest plant formations in Poland /
Language: English
Description: In this deliverable, a description is presented of the fire flammability of the basic forest plant formations in Poland. Two aspects of the study were distinguished. The first (general) aspect was related to analyses of the occurrence of forest fires depending on the selected factors. The other (detailed) aspect focused on the research on the fire properties of selected forest fuels; inter alia, as a result of the general analyses conducted previously. The scope of the study covered: (1) the analysis of the flammability of Poland's forests, taking into account - the CORINE 2000 classification of land uses, the site and stand conditions (forest site types, tree species, stand age), the weather conditions and seasonality of forest fire outbreaks, the impact of climate change on forest flammability; (2) the investigation into the physico-chemical properties of basic forest fuels, including - the combustion heat and the calorific value, the ignition temperature, the smoulder temperature, the ignition time, the drying capacity, the fire load and structure, fire gas emissions, the spread of forest fires.
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