scholarly journals Easy-To-Interpret Procedure to Analyze Fire Seasonality and the Influence of Land Use in Fire Occurrence: A Case Study in Central Italy

Fire ◽  
2020 ◽  
Vol 3 (3) ◽  
pp. 46
Author(s):  
Sofia Bajocco ◽  
Carlotta Ferrara ◽  
Daniela Guglietta ◽  
Carlo Ricotta

Fire frequency and fire seasonality are among the main components of the fire regime. In the Mediterranean Basin, climate directly drives fire occurrence, controlling fuel flammability and determining the fire-prone conditions, so that intense fires prevail during the dry and warm season of the year. However, humans also play a direct role in wildfire regimes, severely altering fuel features, fire policies and land-use management, as well as the timing and location of fire ignitions, to such an extent that anthropogenic activities have overcome the role of climate in shaping fire regimes. The main purpose of this work is to propose a graphical tool capable of identifying the most fire-prone portions of the territory and to explore the differences between the summer and winter fire risk; to this end, we analyzed the seasonal fire risk in the Latium region (central Italy) and its drivers in terms of land-use types, by using a fuel phenology framework. The results demonstrated that climate is not the main cause of bimodal seasonality in fire occurrence and that the existence of two annual fire seasons in Latium is strongly correlated with how humans use fire as a land management tool. The proposed approach may represent an easy-to-interpret pyrogeographical framework applicable in any environment and updatable over time, useful for identifying spatial gradients, and for recognizing fire regime temporal patterns.

PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e2649 ◽  
Author(s):  
G. Matt Davies ◽  
Colin J. Legg

Fire is widely used as a traditional habitat management tool in Scotland, but wildfires pose a significant and growing threat. The financial costs of fighting wildfires are significant and severe wildfires can have substantial environmental impacts. Due to the intermittent occurrence of severe fire seasons, Scotland, and the UK as a whole, remain somewhat unprepared. Scotland currently lacks any form of Fire Danger Rating system that could inform managers and the Fire and Rescue Services (FRS) of periods when there is a risk of increased of fire activity. We aimed evaluate the potential to use outputs from the Canadian Fire Weather Index system (FWI system) to forecast periods of increased fire risk and the potential for ignitions to turn into large wildfires. We collated four and a half years of wildfire data from the Scottish FRS and examined patterns in wildfire occurrence within different regions, seasons, between urban and rural locations and according to FWI system outputs. We used a variety of techniques, including Mahalanobis distances, percentile analysis and Thiel-Sen regression, to scope the best performing FWI system codes and indices. Logistic regression showed significant differences in fire activity between regions, seasons and between urban and rural locations. The Fine Fuel Moisture Code and the Initial Spread Index did a tolerable job of modelling the probability of fire occurrence but further research on fuel moisture dynamics may provide substantial improvements. Overall our results suggest it would be prudent to ready resources and avoid managed burning when FFMC > 75 and/or ISI > 2.


Nativa ◽  
2020 ◽  
Vol 8 (1) ◽  
pp. 112
Author(s):  
Juliana Marchesan ◽  
Elisiane Alba ◽  
Cristina Tabarelli ◽  
Eliziane Pivoto Mello ◽  
Dionatas Henrique Honnef ◽  
...  

O objetivo deste trabalho foi realizar o mapeamento das áreas suscetíveis a ocorrência de incêndios na Estação Ecológica do Taim, Rio Grande do Sul. Para a obtenção das variáveis estáticas e dinâmicas, foram utilizadas imagens do satélite Landsat 8 e imagens de Radar para a determinação da topografia da área de estudo. Como variáveis dinâmicas utilizou-se a precipitação, temperatura e uso e cobertura da terra, enquanto que variáveis estáticas foram a hipsometria, declividade e distância das estradas. Cada variável foi estratificada e posteriormente ponderada numericamente quanto a sua suscetibilidade a ocorrência a incêndio. As variáveis dinâmicas e estáticas geradas foram integradas utilizando uma equação ponderada resultando no risco de incêndios para a área de estudo. A região central da Estação Ecológica do Taim apresentou maior suscetibilidade a incêndios, englobando a classe de alto risco, totalizando 4.219,56 ha (41,61%), enquanto as regiões periféricas apresentaram risco muito baixo a ocorrência de incêndios, abrangendo 5.419,35 ha (53,44%). As variáveis de maior contribuição à ocorrência de incêndios corresponderam ao uso e cobertura da terra e a temperatura, sendo as áreas de maior risco localizadas na parte central e próximo às estradas, nas quais estão ocupadas por campo nativo. Assim, esses locais devem ter maior atenção e recursos para combate de possíveis incêndios.Palavras-chave: Landsat 8; variáveis dinâmicas e estáticas; geoprocessamento. FIRE RISK AT THE ECOLOGIAL STATION OF TAIM, RIO GRANDE DO SUL ABSTRACT: The objective of this work was to map the areas susceptible to the occurrence of fires at the Taim Ecological Station, Rio Grande do Sul. In order to obtain the static and dynamic variables, Landsat 8 satellite images and Radar images were used to determine the topography of the study area. As dynamic variables were used the precipitation, temperature and land use and coverage, while static variables were hypsometry, slope and distance of roads. Each variable was stratified and numerically weighted as to its susceptibility to fire occurrence. The dynamic and static variables generated were integrated using a weighted equation resulting in fire risk for the study area. The central region of the Taim Ecological Station presented higher susceptibility to fires, encompassing the high risk class, totaling 4,219.56 ha (41.61%), while the peripheral regions had a very low risk of occurrence of fires, covering 5,419.35 ha (53.44%). The variables of greatest contribution to the occurrence of fires corresponded to the land use and land cover and the temperature, being the areas of greater risk in the central region and near the roads, in which they are occupied by the native field. Thus, these sites should have greater attention and resources to combat possible fires.Keywords: Landsat 8; dynamic and static variables; geoprocessing.


2012 ◽  
Vol 21 (1) ◽  
pp. 86 ◽  
Author(s):  
Amy E. Hessl ◽  
Uyanga Ariya ◽  
Peter Brown ◽  
Oyunsannaa Byambasuren ◽  
Tim Green ◽  
...  

Rising temperatures are expected to increase wildfire activity in many regions of the world. Over the last 60 years in Mongolia, mean annual temperatures have increased ~2°C and the recorded frequency and spatial extent of forest and steppe fires have increased. Few long records of fire history exist to place these recent changes in a historical perspective. The purpose of this paper is to report on fire history research from three sites in central Mongolia and to highlight the potential of this region as a test case for understanding the relationships between climate change, fire and land use. We collected partial cross-sections from fire-scarred trees and stumps at each site using a targeted sampling approach. All three sites had long histories of fire ranging from 280 to 450 years. Mean Weibull fire return intervals varied from 7 to 16 years. Fire scars at one protected-area site were nearly absent after 1760, likely owing to changes in land use. There is limited synchrony in fire occurrence across sites, suggesting that fire occurrence, at least at annual time scales, might be influenced by local processes (grazing, human ignitions, other land-use factors) as well as regional processes like climate. Additional data are being collected to further test hypotheses regarding climate change, land use and fire.


2019 ◽  
Author(s):  
Lina Teckentrup ◽  
Sandy P. Harrison ◽  
Stijn Hantson ◽  
Angelika Heil ◽  
Joe R. Melton ◽  
...  

Abstract. Understanding how fire regimes change over time is of major importance for understanding their future impact on the Earth system, including society. Large differences in simulated burned area between fire models show that there is substantial uncertainty associated with modelling global change impacts on fire regimes. We draw here on sensitivity simulations made by seven global dynamic vegetation models participating in the Fire Model Intercomparison Project (FireMIP) to understand how differences in models translate into differences in fire regime projections. The sensitivity experiments isolate the impact of the individual drivers of fire, which are prescribed in the simulations. Specifically these drivers are atmospheric CO2, population density, land-use change, lightning and climate. The seven models capture spatial patterns in burned area. However, they show considerable differences in the burned area trends since 1900. We analyse the trajectories of differences between the sensitivity and reference simulation to improve our understanding of what drives the global trend in burned area. Where it is possible, we link the inter-model differences to model assumptions. Overall, these analyses reveal that the strongest differences leading to diverging trajectories are related to the way anthropogenic ignitions and suppression, as well as the effects of land-use on vegetation and fire, are incorporated in individual models. This points to a need to improve our understanding and model representation of the relationship between human activities and fire to improve our abilities to model fire for global change applications. Only two models show a strong response to CO2 and the response to lightning on global scale is low for all models. The sensitivity to climate shows a spatially heterogeneous response and globally only two models show a significant trend. It was not possible to attribute the climate-induced changes in burned area to model assumptions or specific climatic parameters. However, the strong influence of climate on the inter-annual variability in burned area, shown by all the models, shows that we need to pay attention to the simulation of fire weather but also meteorological influences on biomass accumulation and fuel properties in order to better capture extremes in fire behavior.


2020 ◽  
Author(s):  
Farina de Waard ◽  
Alexandra Barthelmes ◽  
Hans Joosten

<p>Peatland ecosystems provide critical ecosystem-services such as water and carbon storage and harbor unique biodiversity. Once ignited, peat fires may burn uncontrollably for weeks or months resulting in rapid ecosystem degradation and excessive CO<sub>2</sub>- Emissions. Despite the impact of peat fires on ecosystem services and climate, peatland fire regimes remain poorly characterized for many parts of the world. Here we investigate the global occurrence of peatland fires over the last two decades.</p><p>We estimate the global extent of peatland fires from 2009 to 2018 and identify drivers of variability and trends using a global peatland map (Global Peatland Database /Greifswald Mire Centre 2019), active fire detections from the Moderate Resolution imaging Spectroradiometer (MODIS), and several fire regime and climate anomaly-datasets. The data were used to delineate 14 ‘Peatland Fire Regions’ (PFR).</p><p>Our results indicate that between 2009 and 2018 globally 553,950 km² of peatland have been affected by fire (7.88 % of the global peatland area), whereas patterns and trends are widely differing. The extent of fire-affected area in the PFRs of Boreal North America and Boreal Eurasia both exceeded 80,000 km², which for both areas accounts for ~3.5 % of the peatland area. In the same time, over 120,000 km² were affected in both Central Asia and Equatorial Asia, i.e. ~23 % of their respective peatland area.</p><p>Northern peatlands are rather subject to natural fires and fire incidence is mostly driven by climate anomalies like droughts. Large peaks in fire occurrence in Boreal North America and Boreal Eurasia were correlated with higher temperatures and less rain. The strong linkage of inter-annual fire variability to temperature anomalies suggests that in these regions fire frequency and intensity may increase in future.</p><p>In tropical regions, particularly those of Africa and Asia, peatland fires tended to occur on degraded peatlands and fires occurred often multiple times on the same site during our study period. While inter-annual variability in fire occurrence was strongly determined by climate, the long term trends in these regions are dominated by human land management. In Africa the fire affected peatland area was rather constant over the years and fires had the highest return frequency, which reflects the widespread culture of burning in land reclamation and agriculture.</p><p>Southern/Equatorial Asia and to some extent South America showed peaks correlated with ENSO associated drought events, leading to the largest fire-affected peatland area in just one year in the Equatorial Asia region of 50,900 km² (in 2015).</p>


2020 ◽  
Author(s):  
Patrícia S. Silva ◽  
Julia A. Rodrigues ◽  
Filippe L. M. Santos ◽  
Joana Nogueira ◽  
Allan A. Pereira ◽  
...  

<p>Fire is a natural disturbance in the Brazilian savannas, Cerrado, with substantial ecological and economic impacts. Most studies have characterized the fire regime in this biome using climate drivers but neglected the geographical variation of anthropogenic activities. These factors can trigger inappropriate fire-fighting decisions and biodiversity conservation policies. This takes special relevance in fire-prone biomes with recent fire management policies as Cerrado, which have been highly modified over the last decades due to changes in land use and climate. </p><p>Here, we aim to identify how variations in climate and anthropogenic drivers influence burned area (BA) trends at the regional level (microregions) in Cerrado. We evaluated satellite-derived BA (MCD64, collection 6) for 172 microregions from 2001 to 2018 across the entire biome. The Canadian Forest Fire Weather Index (FWI) was used as a proxy of climate using meteorological variables from ECMWF’s ERA5 reanalysis product. The human leverage, considered here as population density (PD) and land use (LU), were derived, respectively, from the annual census of the Brazillian Institute of Geography and Statistics (IBGE) and from a Brazilian platform of annual land use/cover mapping (MapBiomas). Recent BA trends considering the drivers FWI, LU and PD, were estimated using the non-parametric Theil-Sen regression and the modified Mann-Kendall test. </p><p>Results showed BA trends over the last 18 years were significant and spatially contrasted along Cerrado: positive trends were found in the north-eastern region (in particular, the most recent agricultural frontier in Brazil: MATOPIBA) whereas the south-western region showed negative trends. PD showed positive trends in all microregions and, similarly, LU obtained positive trends over most of Cerrado. Positive FWI trends were also found over the central and north-eastern regions and FWI was the driver that explained most of BA variance in Cerrado. LU and PD were found to have much more complex relations with BA. Moreover, regarding the seasonal variability of microregions with positive and negative trends, the former were found to begin earlier in June and last longer, indicating that the overall fire season in Cerrado may be extending. </p><p>The approach presented here allows the exploration of recent trends affecting fires, crucial to inform and support better allocation of resources in fire management under current and future conditions.</p><p>The study was funded by Conselho Nacional de Desenvolvimento Científico e Tecnológico, Brazil (CNPQ) through grants 305159/2018-6 and 441971/2018-0. P. Silva is funded by Fundação para a Ciência e a Tecnologia (FCT), grant number SFRH/BD/146646/2019.</p>


2021 ◽  
Vol 25 (7) ◽  
pp. 1257-1262
Author(s):  
E.O. Toyinbo ◽  
R.A. Fasasi ◽  
C.F. Agbor ◽  
C.O. Fakorede

Mankind’s existence and modification of the landscape have had a profound effect on the natural environment. Anthropogenic activities such as agriculture, mining, deforestation and construction have influenced the shifting patterns of land use. This has resulted in a significant effect on local weather and climate. The use of remote sensing data in recent times has been of immense help in monitoring the changing pattern of vegetation. Therefore this study utilized remote sensing and geographic information system (GIS) methods to identify factors responsible for land use land cover (LULC) changes in Oluwa Forest Reserve between 1984 and 2017. The result showed that Primary forest was reduced by about 5% between 1984 and 2000 and by about 12% between 2000 and 2017 and the non-forest got increased by about 4% and 2% from 1984 to 2000 and from 2000 to 2017 respectively. Future forecast shows that primary forest will decrease by about 3% while the non-forest will increase by 5% by 2034. The results also revealed that the changes in forest cover between 2000 and 2017 were actively influenced by the closeness of settlements to the forest. It is therefore recommended that the findings of this study should be adopted by relevant authorities as a useful forest management tool.


2010 ◽  
Vol 19 (3) ◽  
pp. 253 ◽  
Author(s):  
B. M. Wotton ◽  
C. A. Nock ◽  
M. D. Flannigan

The structure and function of the boreal forest are significantly influenced by forest fires. The ignition and growth of fires depend quite strongly on weather; thus, climate change can be expected to have a considerable impact on forest fire activity and hence the structure of the boreal forest. Forest fire occurrence is an extremely important element of fire activity as it defines the load on suppression resources a fire management agency will face. We used two general circulation models (GCMs) to develop projections of future fire occurrence across Canada. While fire numbers are projected to increase across all forested regions studied, the relative increase in number of fires varies regionally. Overall across Canada, our results from the Canadian Climate Centre GCM scenarios suggest an increase in fire occurrence of 25% by 2030 and 75% by the end of the 21st century. Results projected from fire climate scenarios derived from the Hadley Centre GCM suggest fire occurrence will increase by 140% by the end of this century. These general increases in fire occurrence across Canada agree with other regional and national studies of the impacts of climate change on fire activity. Thus, in the absence of large changes to current climatic trends, significant fire regime induced changes in the boreal forest ecosystem are likely.


2001 ◽  
Vol 31 (9) ◽  
pp. 1526-1539 ◽  
Author(s):  
Joseph A Donnegan ◽  
Thomas T Veblen ◽  
Jason S Sibold

We investigated interannual and multidecadal variability in fire regimes, as related to climate and human land-use in Pike National Forest, central Colorado. Short and long-term trends in fire-scar records were related to tree-ring proxy records of moisture availability and to variability in El Niño – Southern Oscillation (ENSO). Fire occurrence is strongly tied to interannual drought conditions and is associated with cycles of ENSO. Fire events tend to occur in years of reduced moisture availability (La Niña years) and are often preceded by 2–4 years of increased moisture availability (El Niño years). A period of reduced variability in the tree-ring record from 1760 to 1820 AD, roughly corresponds to a period of reduced fire occurrence from approximately 1792 to 1842. Coincident with increased fire occurrence, variability in the climate proxies was high in the middle to late 1800s until the early 1900s. Multidecadal impacts through land use are also evident in the fire record with sharp increases during Euro-American settlement in ca. 1850 and abrupt declines with the start of active fire suppression after ca. 1920. Both humans and climatic variation appear to have interacted synergistically to create long-term trends in fire occurrence over the past two centuries.


2017 ◽  
Author(s):  
◽  
Molly Rooney

A concern over wildfire occurrence, and its relationship to drought and a changing climate has brought increased focus to the interface between the public and fire. Multiple factors, including an increase in fuel loading from decades of continuous fire suppression, changes in land use and ownership, and management strategies, are dampening the success of wildfire suppression rates in some ecosystems. Wildfire occurrence is influenced by many factors ranging from drought and climate oscillations at the regional level to fuel availability and land-use at the site level. This study evaluates and explores the extent, frequency, seasonality, and severity of fires across the Cross Timbers, and through time. Historical fire events were reconstructed at three new study sites in unrepresented geographic locations. Fire event chronologies were developed from fire scars spanning three centuries. These chronologies were compared with data from ten existing sites to evaluate fire regime characteristics and changes at a regional scale. Findings suggest that, while fire frequency has increased following EuropeanAmerican Settlement, fire severity has trended downward. Site differences in fire occurrence exist across the greater Cross Timbers region. The results of this study indicate a prevalence of dormant season fire across the greater Cross Timbers region. Fire events were 2-7 times more frequent when considered at a regional scale. Some of the strongest ENSO signals yet detected in any tree-ring data worldwide are in post oak chronologies of Texas and Oklahoma. Little is known about how the role of climate differs in driving fire occurrence at the site to regional scale. In this region, many studies have attempted to explore how climate drives fire at the site level, but inconsistencies in the results of these studies leave questions about the comparability of these conclusions, and the role of climate in altering climate activity at the regional scale. This study assessed the relationship between climate patterns on fire occurrence in the southcentral U.S. and evaluated the independent and interactive influences of drought and the ENSO on fire occurrences at both site and regional levels. The relationship between fire occurrence and drought was largely unclear at the site scale, but drought was found to be a significant driver of fire synchrony at the regional scale. Drier than expected conditions were observed in the year of fire events at the regional level. This relationship was less apparent in the post-European-American Settlement period.


Sign in / Sign up

Export Citation Format

Share Document