SSS9.11 | Managing wildfires in a changing world

SSS9.11

EDI

Wildfires are a worldwide phenomenon with many environmental, social, and economic implications, which are expected to escalate as a consequence of climate change and land abandonment, management, and planning, further promoting land degradation and decreasing ecosystem services supply.
The current situation demands from the scientific community the study of wildfire effects on the ecosystems and the development of integrated tools for pre- and post-fire land management practices that reduce the vulnerability to wildfires and their impacts. However, this research urges the attention not only from researchers, but also from stakeholders and policy-makers all over the world, since basic resources such as raw materials, water, and soils as well as habitats are at stake.
This session aims at gathering researchers on the effects of wildfires on ecosystems, from wildfire prevention to post-fire mitigation. We kindly invite laboratory, field, and/or modelling studies involving the following topics:
i. prescribed and/or experimental fires;
ii. fire severity and burn severity;
iii. fire effects on vegetation, soil and water;
iv. post-fire hydrological and erosive response;
v. post-fire management and mitigation;
vi. socio-economic studies on pre- and post-fire land management;
vii. fire risk assessment and modelling.

Co-organized by GM4/NH7
Convener: Antonio Girona-GarcíaECSECS | Co-conveners: Diana VieiraECSECS, Paulo Pereira, Marta BassoECSECS, Ana Rita LopesECSECS
Orals
| Fri, 28 Apr, 16:15–18:00 (CEST)
 
Room K2
Posters on site
| Attendance Fri, 28 Apr, 10:45–12:30 (CEST)
 
Hall X3
Posters virtual
| Attendance Fri, 28 Apr, 10:45–12:30 (CEST)
 
vHall SSS
Orals |
Fri, 16:15
Fri, 10:45
Fri, 10:45

Orals: Fri, 28 Apr | Room K2

The oral presentations are given in a hybrid format supported by a Zoom meeting featuring on-site and virtual presentations. The button to access the Zoom meeting appears just before the time block starts.
Chairpersons: Antonio Girona-García, Diana Vieira, Marta Basso
16:15–16:20
16:20–16:30
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EGU23-2268
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SSS9.11
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ECS
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On-site presentation
Elena Aragoneses, Mariano García, and Emilio Chuvieco

Spatially-explicit information on canopy fuel parameters is key for wildfire propagation modelling, emission estimations and risk assessment. This work aims to develop easily-replicable methods to estimate critical fuel canopy parameters from spaceborne LiDAR observations acquired by the Global Ecosystem Dynamics Investigation (GEDI) sensor onboard the International Space Station. GEDI-like pseudowaveforms were modelled from discrete Airborne Laser Scanning (ALS) data and used to select the best GEDI predictor metrics to derive European wall-to-wall forest height and canopy cover maps. Then, GEDI spaceborne footprints were used to generate continental maps of canopy parameters through a two-steps approach: 1) Spatial interpolation of GEDI footprints inside homogeneous forest fuel type polygons, and 2) Modelling machine learning algorithms for the forest fuel type polygons without GEDI footprints inside, using auxiliary multispectral and RADAR imagery and biophysical variables. Our results show the capabilities of remote sensing and GEDI to estimate and map the spatial patterns of critical forest canopy fuel parameters in fire risk prevention and contribute to generating the necessary tools to develop an integrated risk-wise strategy that reduces fire vulnerability of ecosystems across Europe.

How to cite: Aragoneses, E., García, M., and Chuvieco, E.: Estimating and mapping forest canopy fuel parameters from GEDI LiDAR data in Europe, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-2268, https://doi.org/10.5194/egusphere-egu23-2268, 2023.

16:30–16:40
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EGU23-13012
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SSS9.11
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ECS
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On-site presentation
Mariana Silva Andrade, Mortimer M. Müller, Gergo Dioszegi, and Harald Vacik

Changing climate is likely to increase the intensity of forest fires in Austria. Consequently, the investigation of the fire danger situation at the wildland-urban interface is crucial for the planning of prevention measures against future damages. Hence, a comprehensive fire risk assessment study was performed for Austria, in which five components were considered (natural cause for ignition of forest fires, socioeconomic causes for ignition, vegetation structure, meteorological factors and exposition of important infrastructures). The approach for the fire danger assessment determined for the city of Graz, the second largest city in Austria, as high danger level for fire occurrences. Therefore, the present work introduces a case study for this city, focusing on the exposure of settlements and infrastructure to fire events. The relevant infrastructure features were selected, such as residential buildings, power lines, radio stations, railways, highways and traffic and communication buildings, as well as three types of forests with different management objectives (production forest, site protection forest and object protection forest). In order to analyze the interaction between settlements and vegetation in case of forest fires, buffers were used (i.e. buffer sizes for buildings are 10m, 50m and 150m and other settlements are 60m, 100m and 200m). Infrastructure and forest cover were also classified due to their importance: high, medium and low risk of exposition. For example, production forest was considered to bear a lower risk of exposition due to their economic importance compared to protection forests, that have to protect the city from natural hazards like rock falls or mudflows. On the other hand, radio stations carry a high risk of exposition because of their importance for facilitating the communication of the community. In combing the results of the fire danger assessment for the city of Graz with final exposition map the results indicate that areas around radio stations situated in the northwestern area of the city have a higher risk of exposition. As a result, firefighters must pay particular attention to this region for management and evacuation plans.

How to cite: Silva Andrade, M., M. Müller, M., Dioszegi, G., and Vacik, H.: Exploring the fire danger and exposition of settlements at the wildland urban interface: a case study in Graz, Austria, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-13012, https://doi.org/10.5194/egusphere-egu23-13012, 2023.

16:40–16:50
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EGU23-16785
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SSS9.11
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ECS
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On-site presentation
Rebecca Scholten, Yang Chen, Sander Veraverbeke, and James Randerson

Intensifying wildfires in high-latitude forest and tundra ecosystems are a major source of greenhouse gas emissions, releasing carbon through direct combustion and long-term degradation of permafrost soils and peatlands. Several remotely sensed burned area and active fire products have been developed, yet these do not provide information about the ignitions, growth and size of individual fires. Such object-based fire data is urgently needed to disentangle different anthropogenic and bioclimatic drivers of fire ignition, spread and extinction.

We developed an object-based fire tracking method to map the evolution of fires at a sub-daily scale using Visible Infrared Imaging Radiometer Suite (VIIRS) active fire detections. The dataset includes ignitions and sub-daily perimeters of individual fires between 2012 and 2021, which are corrected using finer-scale information on waterbodies. Here, we present first results of this circumpolar arctic-boreal fire atlas. We show circumpolar patterns of arctic-boreal fire activity and disentangle the spatially varying influence of drivers of fires. Most fires, as well as the largest fires, occur on the Eurasian continent. Latitudinal differences in fire characteristics and drivers are important, yet regional and continental differences emerge. Knowledge about regional differences in fire regimes and their drivers is required to better understand contemporary arctic-boreal fire regimes and to constrain models that predict changes in future arctic-boreal fire regimes.

How to cite: Scholten, R., Chen, Y., Veraverbeke, S., and Randerson, J.: Circumpolar patterns of arctic-boreal fire activity, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-16785, https://doi.org/10.5194/egusphere-egu23-16785, 2023.

16:50–17:00
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EGU23-9836
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SSS9.11
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ECS
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On-site presentation
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Monica Corti, Laura Corti, Andrea Abbate, Monica Papini, and Laura Longoni

In a climate change scenario, natural disasters and their consequences are expected to increase. In particular, it is proven that the raise of global temperature will drive a higher occurrence of wildfires, leading to a wide range of problems in the mountain areas, such as slope instabilities. As confirmed by many authors, in addition to the disruption of vegetation, wildfires have indeed severe effects over the natural slopes, linked to the hydrological changes provoked by burning, which may cause further economic losses and casualties.

The risen probability of flash flooding and debris flows after wildfires is recognized to depend on an alteration of the soil hydrological properties, and in particular of the soil infiltration capacity. Many studies in literature focused on the trends of soil infiltration recovery after fire, but none of them regards Alpine case studies and only a few are European, even if wildfire phenomenon is relatively common nowadays in the Alps. Furthermore, rainfall thresholds for possible landslide triggering have not been defined for wildfire-affected areas yet.

This work investigates the impact of a wildfire occurred in 2019 in the Southern Alps, starting from the data collected during three years of monitoring activity at different spatial scales and after laboratory rainfall simulations. The investigation of the burnt area was conducted both remotely, by the analysis of Copernicus Sentinel-2 imagery, and throughout field surveys, by performing falling-head infiltration tests. The monitoring activity was distributed over three different sub-areas, taking into account the different fire severity (burnt or unburned sub-area) and the original vegetation type (pine woods or grassland). Moreover, soil samples were collected inside those sub-areas for further laboratory permeability tests and rainfall simulations.

Results were used to retrieve recovery trends for the calibration of a simple 1D hydrogeological model.

In particular, the remote sensing analysis helped to evaluate a recovery time of seven years of the site to pre-fire conditions. On the other hand, field monitoring suggested the recovery to depend mostly on the restoration of the canopy protection, as preventing factor for direct responses to rainfall and soil erosion.

How to cite: Corti, M., Corti, L., Abbate, A., Papini, M., and Longoni, L.: Post-wildfire monitoring for hazard mitigation in Alpine area, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-9836, https://doi.org/10.5194/egusphere-egu23-9836, 2023.

17:00–17:10
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EGU23-9283
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SSS9.11
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On-site presentation
Mara Baudena, V Ramon Vallejo, Jaime Baeza, Aymen Moghli, Alejandro Valdecantos, and Victor M Santana

Forest fires and extreme droughts will continue to be main disturbances in Mediterranean ecosystems, given the ongoing and projected climatic changes. In fact, an exacerbation of some aspects of their regime is expected. In this perspective, it is fundamental to design adaptive management strategies that can reduce the impact of disturbances and increase ecosystem resilience. To achieve this, it is necessary to develop an integrated management, able to select the best combination of restoration actions for different scenarios. Here, we address the effectiveness of the combination of several actions related to fuel reduction and restoration after fire in the long term, to increase the presence of resprouting species and mitigate fire occurrence, for different future climate change scenarios. Fuel reduction treatments include the application of shrub clearing at different intensities and frequencies. Restoration actions comprise the plantation of resprouting species, aiming to increase ecosystem resilience. We used a simple, ecological, published model, specifically developed for Mediterranean ecosystems and including species competition and post-fire responses, which we calibrated using the recorded vegetation response to treatments. Our results point out that, if we look for more resilient ecosystems in the next decades, we will need an intensification of fuel reduction treatments. Noticeably, including resprouting species has an important effect in the ecosystem. However, the success of these actions will be variable depending on the climate scenario.

How to cite: Baudena, M., Vallejo, V. R., Baeza, J., Moghli, A., Valdecantos, A., and Santana, V. M.: Long-term management actions of fire-prone Mediterranean ecosystems under climate change using fuel reduction and post-fire restoration, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-9283, https://doi.org/10.5194/egusphere-egu23-9283, 2023.

17:10–17:20
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EGU23-10798
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SSS9.11
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ECS
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On-site presentation
Alexandria Thomsen and Mark Ooi

Fire is a major factor shaping plant communities, and plant species have evolved to persist through a fire regime, broadly characterised by the frequency, intensity, and season of burns typical of their region. However, historical fire regimes are shifting with changing climate and other factors, including increased ignition sources, and implemented fires, producing more frequent burns of varying intensity. As such, seasonality of fire is shifting and despite the effects of fire on plant persistence being well studied, there is still little understanding on the effects of fire season. In this study, we set up two sites with five treatment areas, an early autumn burn, late autumn burn, early spring burn, late spring burn and a control. We surveyed multiple shrub species for impacts of seasonal burns on resprouting vigour and post-fire flowering in the mediterranean region of South Australia. Fire severity was also measured using soil temperatures, canopy cover consumption and minimum twig diameter. We found that fire response to fire season varied between trait type included seed storage type and seed dormancy type. This study highlights the impact of season of fire and that it should be considered when making species management decisions for plant species persistence.

How to cite: Thomsen, A. and Ooi, M.: Shifting fire season: who has it worse resprouters, or obligate seeders?, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-10798, https://doi.org/10.5194/egusphere-egu23-10798, 2023.

17:20–17:30
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EGU23-4580
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SSS9.11
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ECS
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On-site presentation
Gaël Thery, Farid Juillot, Julie Jeanpert, Damien Calmels, Guillaume Morin, Emmanuelle Montarges-Pelletier, Elora Bourbon, Isabelle Kieffer, Pierre Genthon, and Cécile Quantin

In New Caledonia, a significant fraction of soils developed on the Peridotite Nappe are naturally enriched in trace metals, such as nickel and chromium, that can be remobilized upon wildfires (Thery et al., 2022). In this Pacific archipelago, the average annual burnt vegetation surface is estimated to be 30,000 ha, representing 2% of the total land surface (Dumas et al., 2013). However, much larger surfaces can burn during strong El Nino years. This was notably the case in 2016 at Ile des Pins, in the South part of the archipelago, where the burnt surface reached 1000 ha compared to an average annual value of 300 ha. Concomitantly, a dramatic increase in nickel concentrations could be observed in some water supply catchments, with some values reaching up to 4000 µg/L compared to the WHO and European guidelines of 70 µg/L and 20 µg/L, respectively. This situation led the authorities to order some investigations to better understand the link between these increased wildfires and the degradation of freshwater quality.

In this presentation, we will discuss the results of these investigations performed for two years on the dynamics and biogeochemistry of nickel across a drinking water catchment supplied by both surface and groundwater. The surface water originates from a doline, which is a characteristic feature of karstic landscapes frequently observed in the lateritic landscapes on ultramafic rocks from New Caledonia (Jeanpert et al., 2016). Geochemical analyses of the surface water collected in the burnt doline showed very high nickel concentration (i.e. up to 300,000 µg/L) compared to groundwaters (i.e below 30 µg/L). These surface waters were also found enriched in sulfate (i.e. up to 3200 mg/L) compared to groundwaters (i.e. below 8 mg/L). Water isotopes analyses allowed to propose a simple mixing model between these two end-members to reconstitute the water supply at the drinking water catchment. In addition, mineralogical characterization of the doline sediments and XAS-derived analysis of nickel speciation allowed to evidence a mixed Mg/Ni-sulfate and Ni/Fe-sulfides as the two major Ni-bearing mineral species. Although the sulfides are common species in sedimentary settings, the occurrence of a mixed Mg/Ni sulfate was considered to result from the large 2016 wildfires that impacted the nickel biogeochemistry in the sediments. The high solubility of this latter mineral species is probably playing a major control on nickel concentration in the water that is supplied to the downstream drinking water catchment.

This study brings further understanding on how wildfires can impact drinking water catchments quality by modifying the biogeochemical cycling of trace metals across their related watersheds. In the case of New Caledonia where most of drinking water catchments are supplied by surface water (a significant fraction of them being related to ultramafic watersheds), it spreads awareness to local policy-makers about the vulnerability of the water resource relative to wildfires. At a larger scale, it also put some warning on the possible impact of wildfires on drinking water catchments related to ultramafic watersheds worldwide.

 

How to cite: Thery, G., Juillot, F., Jeanpert, J., Calmels, D., Morin, G., Montarges-Pelletier, E., Bourbon, E., Kieffer, I., Genthon, P., and Quantin, C.: How wildfires can impact nickel concentration and biogeochemistry at ultramafic drinking water catchments: An example study in New Caledonia, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-4580, https://doi.org/10.5194/egusphere-egu23-4580, 2023.

17:30–17:40
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EGU23-14379
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SSS9.11
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ECS
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On-site presentation
Matteo Nigro, Roberto Giannecchini, Marco Doveri, Matia Menichini, and Ilaria Baneschi

Wildfires are recognized as one of the most affecting ecological agents, altering geomorphological processes, hydrologic cycles, and water quality. On average from 50,000 to 65,000 fires occur in Europe every year, burning approximately 500,000 ha of forested areas. Between September 2018 and February 2019 two large wildfires burnt nearly 1,400 ha of forests and farmlands in the Pisano Mount area (northwestern Tuscany). The mountainous morphology of the area linked to the proximity to the sea causes high precipitation variability and intensity. This, joined with low permeability bedrock (mainly quartzites, schists, and phyllites) and with the extensive vegetation coverage, make the study site a hot spot for surface waters analysis. Moreover, burnt catchments are of primary importance in the recharge processes of the groundwater resources of the costal plain, which are exploited by a large number of inhabitants and agricultural facility. Consequently, the present study is aimed at understanding and quantifying the wildfire impacts on the hydrogeological dynamics and water quality in the studied catchments. Such impacts are being evaluated by comparing burnt and unburnt catchments, which were selected to be as similar as possible from geological, morphological, and vegetational perspectives. The multi-parameter selection method involved Principal Component Analysis and Distance analysis on many potentially feasible catchments. A network of automatic monitoring instruments was deployed on site. Five hydraulic sections of the main streams draining the area were monitored for hydraulic level and physico-chemical parameters. Hydrographs analysis was performed to infer differences in hydrogeological dynamics between burnt and unburnt basins. Monthly samples were collected for stream water and groundwater chemical analysis. In addition, four plate lysimeters were installed to sample soil water for its chemical characterization. The chemical analysis involved major anions and cations, trace elements, water isotopes, and organic compounds, to search for chemical perturbation potentially arising from the wildfire. The investigation highlighted various differences between the burnt and unburnt basin, mainly for the surface waters. The streams draining the burnt areas present different hydraulic behaviour and changes in physiochemical parameters in response to rainfall events. Moreover, the yearly variation of physiochemical parameters and chemical characteristics present an higher variance for those streams draining wildfire affected catchments.

How to cite: Nigro, M., Giannecchini, R., Doveri, M., Menichini, M., and Baneschi, I.: Mediterranean catchments post-fire hydrogeological behavior and water quality: insights from the Pisano Mount area (Tuscany, Italy), EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-14379, https://doi.org/10.5194/egusphere-egu23-14379, 2023.

17:40–17:50
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EGU23-13669
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SSS9.11
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ECS
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On-site presentation
Sara Negri, Beatrice Giannetta, Giulia Mantero, Silvia Stanchi, Raffaella Marzano, Matteo Garbarino, Luisella Celi, and Eleonora Bonifacio

Wildfires play the role of ecosystem shapers in the majority of terrestrial biomes. Nowadays, their regimes are changing as a consequence of land abandonment and climate change. After-fire dynamics are widely studied in North America and Mediterranean environments. However, soils developed in different biomes might not unequivocally respond to fire-induced heating, and forests of the Western Italian Alps are not unfamiliar to fire occurrence.

For these reasons, we conducted several experiments (at plot and lab scale) at environmentally realistic conditions to systematically assess the impacts of fire on the physico-chemical properties of soils belonging to the Italian Alpine ecological region.

A homogenous pine forest (Pinus sylvestris L.) located in a mountain region near Torino experienced the passage of a severe and large wildfire in fall 2017. The field survey carried out in 2020 revealed that lower organic carbon (OC) contents and higher bulk density (BD) values were associated to a greater fire severity. Abundance of pyrogenic carbon was related to the steepness degree, as a consequence of erosion. In the superficial horizons, the naturally high WR expected from soils developed under a conifer stand was not present.

To elucidate mechanisms regulating WR occurrence and evolution, the thermal transformations borne by Alpine soils were investigated at controlled laboratory conditions. Topsoil samples displayed extremely different wettable behaviors upon increasing temperatures (Ts), with or without WR build-up. This occurred mainly in relation to content and composition of organic matter (OM), particle size distribution and abundance of iron (Fe) oxides. Notwithstanding the initial sample hydrophobicity, WR was dramatically lost above 200 °C due to increasing pH values, inducing OM de-sorption from the negatively charged mineral surfaces.

In the same T range, the thermal transformation of soil Fe oxides were found to be primarily directed towards oxidative processes (hematite formation). Ts up to 300 °C could have potentially promoted the stabilization of the remaining (non-combusted) OM, with the synthesis of defect-rich Fe oxides and enrichment in condensed and aromatic compounds, and yet OM was highly dispersible at the high pH values resulting from the thermal treatment, such that OC might be weakly retained on mineral phases in an after-fire scenario.

How to cite: Negri, S., Giannetta, B., Mantero, G., Stanchi, S., Marzano, R., Garbarino, M., Celi, L., and Bonifacio, E.: Heating response patterns of Alpine soils: from a plot-scale to lab experiments., EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-13669, https://doi.org/10.5194/egusphere-egu23-13669, 2023.

17:50–18:00

Posters on site: Fri, 28 Apr, 10:45–12:30 | Hall X3

The posters scheduled for on-site presentation are only visible in the poster hall in Vienna. If authors uploaded their presentation files, these files are linked from the abstracts below, but only on the day of the poster session.
Chairpersons: Paulo Pereira, Ana Rita Lopes
X3.169
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EGU23-7609
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SSS9.11
Seonyoung Park and Kyungil Lee

Abiotic and biotic factors in forest ecosystems can all be significantly and immediately impacted by forest fires. Additionally, fires pose a long-term concern because they release greenhouse gases (GHGs) into the atmosphere, damage habitat, cause soil erosion, and affect local and global temperatures. In the absence of sufficient information on the damaged forests, such as location, area, and burn severity, issues in policy decisions for restoration inevitably arise. In this study, burned areas and severity were mapped using eight spectral indices derived from Sentinel 2 MSI images using machine learning approaches (Random Forest (RF) and Support Vector Machine (SVM)). The dataset from Copernicus Emergency Management Service (CEMS) was employed as the reference truth for burned area and severity. Our approaches were tested for two study sites that had a similar meteorological environment (dry season) and species (coniferous vegetation).  This study presents a novel methodology for mapping burned areas and severity using Sentinel-2 MSI data and CEMS data, aiming at achieving mapping accuracy and transferability. RF performed better than SVM when classifying pixels within heterogeneous regions. The Normalized Burn Ratio (NBR) and Green Normalized Difference Vegetation Index (GNDVI) were quite significant in determining the severity of a fire, indicating that they might be useful in identifying senescent plants. The findings also demonstrated that the CEMS dataset can be used as a reference for classifying fire damage in other regions. The use of this approach makes it possible to quickly and accurately map the extent of the damage caused by forest fires and has applicability for other disasters.

How to cite: Park, S. and Lee, K.: Satellite-based burn severity mapping and evaluating the transferability of Copernicus EMS data using machine learning approaches, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-7609, https://doi.org/10.5194/egusphere-egu23-7609, 2023.

X3.170
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EGU23-8043
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SSS9.11
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ECS
Karen Abogadil and Usman Khan

Wildfires are becoming larger and more severe due to climate change. This trend affects the forest ecosystem and disrupts many eco-hydrologic processes in forested watersheds. Effects can include rapid runoff responses, increased surface runoff, and elevated erosion, leading to lower water quality and long-lasting effects on hydrologic ecosystem services (drinking water supply or flood regulation). However, post-fire hydrology studies often have variable and contrasting results, making cross-study comparisons difficult. Studies are typically short-term and focused on single wildfire events. Additionally, hydrologic ecosystem services are not always considered. This research has two objectives: to determine accurate indicators for post-fire flow responses; and to develop a flood risk map that considers wildfire history and the hydrologic ecosystem services. The study area includes 336 drainage basins (grouped into five ecozones) in British Columbia, Canada, known for its susceptibility to wildfires and floods. The study analyzes 110 years of wildfire data from 1910 to 2020. Of the 824 wildfires in the study period, over 400 fires were identified with five years of continuous streamflow and precipitation daily flow records. Percent changes in low, high, and peak flows were calculated using pre-fire and post-fire values. Using streamflow, precipitation, wildfire perimeters, land cover and topographic data, statistical analyses were done to determine the most influential watershed characteristic in post-fire streamflow responses. To develop the flood risk map, the same data will be combined with socio-economic and demographic data. Preliminary results suggest differing trends for low, high, and peak flows for the five ecozones in BC, demonstrating the importance of geophysical variables on streamflow response. Results will aid in understanding the effects of climate change over 110 years, specifically the wildfire effects on hydrology in forested watersheds and on the hydrologic ecosystem services provided to nearby communities. The determination of accurate post-fire streamflow indicators will also help water resource managers, urban planners, and other decision-makers allocate resources appropriately for long-term water management and reduce post-fire flood vulnerability.

How to cite: Abogadil, K. and Khan, U.: An analysis of 100 years of post-fire streamflow responses of British Columbia watersheds, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-8043, https://doi.org/10.5194/egusphere-egu23-8043, 2023.

X3.171
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EGU23-9015
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SSS9.11
Edward Johnson, Yvonne Martin, and Olga Chaikina

Wildfire disturbances due to lighting strikes are a relatively common occurrence in subalpine forests of the Canadian Rockies. Tree roots found within forest soils are known to undergo decomposition after crown wildfires. As decay progress, this results in changes to tree root characteristics, including the number of remaining tree roots, distribution of tree root diameters and tensile force at failure of remaining roots. These changes, in turn, may impact soil hydrology and the likelihood of geomorphic process occurrence, including debris slides and debris flows. Herein, we present results of an intensive, annual field measurement program covering a period of about one decade that provides information about tree root decay following a crown wildfire in the Canadian Rockies. The crown wildfire burned a total of 17 000 hectares in Kootenay National Park and provided an opportunity to undertake this field measurement program. Hawk Creek drainage basin was the location in which field sampling of tree root data occurred. A total of 15 soil pits over a range of hillslope gradients were dug and key characteristics of all tree roots emerging from walls of soil pits were measured. Numerical analysis of tree root measurements in each year includes the frequency of tree roots in different diameter classes, frequency of tree roots at different depths below the ground surface and lateral root cohesion. One key finding is that tree roots having a smaller diameter fully disintegrate before larger tree roots. In addition, tree roots situated higher in the soil profile (i.e., closer to the surface) decay preferentially compared to tree roots located lower in the soil profile. Results also show that for a given tree root diameter class, the tensile force at failure decreased very rapidly in the first two years after wildfire occurrence. Similarly, the lateral root cohesion decreased rapidly in the first several years following the wildfire, although some root strength was documented even one decade after wildfire occurrence.

How to cite: Johnson, E., Martin, Y., and Chaikina, O.: Tree Root Decay in Soils Following Tree Death after a Crown Wildfire, Canadian Rockies: A Field Investigation , EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-9015, https://doi.org/10.5194/egusphere-egu23-9015, 2023.

X3.172
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EGU23-11387
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SSS9.11
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ECS
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Carmen B. Steinmann, Jonathan Koh, Samuel Lüthi, Samuel Gübeli, Benoît P. Guillod, and David N. Bresch

Wildfires are devastating events destroying large parts of physical assets exposed to them in many regions of the world. Therefore, a high-resolution hazard model is needed to accurately assess socio-economic impacts caused by wildfires. Moreover, a probabilistic representation of the hazard covering the range and likelihood of possible wildfire events under certain conditions allows for a more comprehensive risk assessment. This is crucial for many applications, among others the prioritization of adaptation measures and the pricing of insurance.

We determine burning probabilities based on MODIS hotspots and a set of predictors (weather variables, geography, land use) by using a country-specific machine learning model based on the efficient tree boosting system XGBoost. Subsequently, stochastic wildfire events are generated on the basis of these burning probabilities.

Lastly, the open-source climate risk assessment platform CLIMADA is used to compute socio-economic impacts as the combination of the newly developed hazard, an exposure and a vulnerability. The used exposure LitPop spatially distributes macroeconomic indicators (e.g. produced capital) as a function of night light intensity and population density. The vulnerability is represented by an impact function that was calibrated on historic fire damage data. Combining the stochastic impacts with their respective probabilities results in a globally consistent country-specific model of wildfire risk to physical assets.

How to cite: Steinmann, C. B., Koh, J., Lüthi, S., Gübeli, S., Guillod, B. P., and Bresch, D. N.: Gradient boosting for socio-economic wildfire risk assessment, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-11387, https://doi.org/10.5194/egusphere-egu23-11387, 2023.

X3.173
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EGU23-11995
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SSS9.11
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ECS
Wenyi Xu, Bo Elberling, and Per Lennart Ambus

Recently, the frequency and intensity of wildfires has been increasing in the Arctic as a result of climate change. However, there is still little knowledge on the effects of fire intensity on carbon dioxide (CO2) exchange in arctic tundra ecosystems. We conducted an experimental fire of different burn intensity (i.e., low intensity, high intensity and unburned control) to investigate effects of fire intensity on soil biogeochemical cycles and surface CO2 fluxes over four growing seasons in an arctic heath tundra, West Greenland. Post-fire soil temperatures and soil moisture increased with increasing fire intensity by up to 2.2 ℃ and 18 vol%, respectively. The high-intensity fire also significantly increased soil nitrate concentrations 1 day post fire, but this effect disappeared 1 year post fire. There were no significant effect of fire intensity on soil carbon and phosphorus availability or microbial biomass. The ecosystem shifted from a net CO2 sink to a net CO2 source immediately after the fire, because of the reductions in photosynthetic activity. 1 year post fire the low-intensity burned plots have turned into a net CO2 sink, while the high-intensity burned plots were a net CO2 source for the entire study period. This suggests that the time needed for the burned ecosystem to turn into a net CO2 sink increases with increasing fire intensity. Fire intensity had no effect on ecosystem respiration (ER) immediately after the fire, likely because the increases in microbial respiration caused by elevated soil temperatures and moisture and soil nitrogen availability have offset the decreases in plant respiration. However, 1-3 years after the fire, the high-intensity fire significantly reduced ER rates, suggesting that the moderate increases in microbial respiration only caused by elevated soil temperatures and moisture could not balance out the decreases in plant respiration. Overall, compared with low-intensity fire, high-intensity fire not only combusts more biomass or soil organic matter and releases more CO2 during the fire, but also prolongs the duration of the burned areas as a net CO2 source and consequently enhances post-fire CO2 losses.

How to cite: Xu, W., Elberling, B., and Ambus, P. L.: Effects of fire intensity on CO2 exchange in an arctic tundra ecosystem, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-11995, https://doi.org/10.5194/egusphere-egu23-11995, 2023.

X3.174
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EGU23-13680
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SSS9.11
Célia Gouveia, Tiago Ermitão, Isabel F. Trigo, and Patrícia Páscoa

Southern Europe is considered a fire-prone region, and fire events occur here every summer. In this context, large fires have hit Portugal over the last 20 years, due to frequent hot and dry summer conditions, and also to high fuel availability in ecosystems. Moreover, climate change in the Mediterranean basin is expected to increase the severity of fire weather conditions and therefore to increase the occurrence of extreme fire seasons.

Recent catastrophic fire seasons have led to the implementation of a set of policies during the months before the fire-season, aiming at fire prevention and suppression, which can in turn increase the combat efficiency of fires during the fire season. Therefore, this work intends to contribute to fire prevention by identifying regions with a high likelihood to burn.

A Principal Components Analysis (PCA) was applied to several climatological, ecological, and biophysical variables, related to fire weather, fuel availability, and elevation covering the period from 2001 to 2021. Results allowed to assess the areas where large fires were more likely to occur in 2022. The central and southernmost regions of Portugal showed a stronger signal in the PCA, indicating a likely high susceptibility to future fire events. The association of fuel accumulation since the last fire event with elevation and favourable fire weather conditions explains most of the variability of the first six PCs. These results were compared with the fires that occurred in 2022, and a match between larger burned areas and high signals in the PCA was found, highlighting the usefulness of this methodology.

This study was supported by FCT (Fundação para a Ciência e Tecnologia, Portugal) through national funds (PIDDAC) – UIDB/50019/2020, and under the projects FlorestaLimpa (PCIF/MOG/0161/2019).

How to cite: Gouveia, C., Ermitão, T., Trigo, I. F., and Páscoa, P.: Mapping fire susceptibility in Portugal, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-13680, https://doi.org/10.5194/egusphere-egu23-13680, 2023.

X3.175
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EGU23-15531
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SSS9.11
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ECS
Bushra Sanira Asif, Paolo Fiorucci, and Nicolò Perello

Over the past century, severe wildfire events have been recorded globally due to climate change. Changes in climatic conditions may change forest landscape by modifying rates of vegetation formation, shifts in temperature and tree species shift. There was a near-complete loss of native tree species in some affected areas and loss of these species were most strongly linked to burn frequency. Many questions remain regarding how these changes will occur across landscapes and how disturbances such as wildfires may interact with changes to climate and vegetation. Forest management is used to proactively modify forest structure and composition to improve fire resilience. Yet, research is needed to assess how to best utilize the resources to reduce damages due to forest fires. Human communities also exist within these landscapes, and decision regarding how to manage forests must carefully consider how management will affect such communities.

The scientific literature recognizes the importance of incorporating stakeholders' knowledge and the active role of local communities to enhance and strengthen adaptive capacities to fire risk management. However, the research in this area seems to be still at the initial stage, and this gap needs to be addressed through actions that value the knowledge and voices of stakeholders and local communities. This research aims to contribute to this gap by sharing the process with the application of participatory mapping GIS involving forest stakeholders in a forest fire risk area in Liguria, Italy. To investigate local community preferences for forest management, public participation geographic information systems (PPGIS) mapping exercise is a good tool for local residents to express their views on fire reduction treatments (for example, commercial harvest, non-commercial harvest and prescribed fire). Emergent themes from the mapping exercise can be used to inform alternative management scenarios to explore the usefulness of using PPGIS to generate modelling inputs. Scenarios will be ranged from restoration-only treatments to short-rotation commercial harvest. The use of PPGIS is useful for outlining the range of forest management preferences within the local community, for identifying areas of agreement among residents who have otherwise polarized views, and for generating modelling inputs that reflect views that may not be obtained through existing official channels for public participation. Involving forest stakeholders in the decision-making process may increase public acceptance of the forest fire treatments needed to modify wildfire trajectories under future climate conditions and to improve forest resilience.

How to cite: Asif, B. S., Fiorucci, P., and Perello, N.: Using stakeholder-developed forest management maps to model fire reduction treatment effects on forest fire, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-15531, https://doi.org/10.5194/egusphere-egu23-15531, 2023.

X3.176
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EGU23-7744
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SSS9.11
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ECS
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Agustiyara Agustiyara and Balázs Székely

This research aims to shed light on remote sensing data, focusing on remote sensing for forest fires which still largely separates these expertise techniques. In this situation, the use of sentinel data makes it possible to make assessments related to land and forest fires by assessing the land cover function of land fires. The first specific location shows that land fires are clearly visible, especially on the Rupat island which is part of Bengkalis Regency, Riau Province, Indonesia. In a general sense, Rupat Island is a small island with a peatland ecosystem. This becomes complex when various land functions and activities, such as the development of the oil palm plantation industry, protected forest areas, industrial plantation forest (HTI) company areas, peat land, and other land uses activities are found on this island. Forest fires cause extreme long-term damage to the environment, wildlife, flora, and property including forestry and agricultural holdings every year. Along with improving the detection of and response times to such fires, there is also a need to improve post-event delineation, assessment, and monitoring of the affected areas. Such post-event analysis can then feed back into strategies and policies for wildfire prevention, prediction, mitigation, and response. However, the detection of such fires by these tools considers the accuracy in terms of the exact location and extent of land classification and burnt areas. The use of statistically significant remote sensing, the research process two products between 2019 and 2020. The research use data equation through the Sentinel-3 data, where the detection of land fires that are clearly visible in the "fire detection" image by performing a data algorithm to ensure that the fire point is no cloud cover. Sentinel-2 data was also used to explain the loss of vegetation on peatlands in the area of land fires, which clearly shows changes in burnt areas. With the same combination of analyses, sentinel-1 data was also used to clarify the land cover in the fire area, where the classification algorithms (forest) and other functions in sentinel-1 data were identified. Therefore, the use of remote sensing primarily aims to highlight the importance of data fusion and integrate it into the multiple factors and motives for forest and land fires.

How to cite: Agustiyara, A. and Székely, B.: Detecting Forest Fires by Using Remotely Sensed Data in Riau, Indonesia, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-7744, https://doi.org/10.5194/egusphere-egu23-7744, 2023.

X3.177
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EGU23-9805
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SSS9.11
Florian Kraxner, Andrey Krasovskiy, Charlotte Kottusch, Shelby Corning, Dmitry Schepaschenko, Harald Vacik, Mathias Neumann, Mortimer Mueller, Arne Arnberger, Herbert Formayer, David Leidinger, Tobias Schadauer, Susanne Karel, and Christoph Bauerhansl

The main objective of this Austria Fire Futures study is to develop a unique and innovative concept containing new sets of fire risk hotspot maps at highest spatial resolution under various climate change scenarios and integrate novel insights on local fuel types into forest and forest fire risk models, including new variables such as morphology and recreational activities. To generate such maps on a local scale, fire hazard modeling is necessary to identify endangered forest types in combination with topographic effects. Furthermore, recent fire events in the Austrian Alps show that social aspects, particularly the hiking tourism, are paid too little attention to.
Based on the above motivation, we believe that an innovative and improved fire risk hotspot mapping is the fundament for all further forest- and wildfire prevention and hence needs to be seen as an indispensable tool for an integrated fire management (prevention, suppression, post fire measures) while substantially contributing to mitigating climate change as well as minimizing damage to ecosystems, their services, and people.
The study will improve our understanding of fire-vulnerable forest areas that may shift over time and space given the underlying climate and fuel assumptions. This will allow experts, practitioners, and the interested public to take a look into the future in order to comprehend and derive solid short-/medium-/and long-term recommendations for fire resilient and sustainable forest management and fire emergency planning.

How to cite: Kraxner, F., Krasovskiy, A., Kottusch, C., Corning, S., Schepaschenko, D., Vacik, H., Neumann, M., Mueller, M., Arnberger, A., Formayer, H., Leidinger, D., Schadauer, T., Karel, S., and Bauerhansl, C.: Wildfire Hot Spot Mapping - Austria Fire Futures, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-9805, https://doi.org/10.5194/egusphere-egu23-9805, 2023.

X3.178
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EGU23-14313
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SSS9.11
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ECS
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Nicolò Perello, Andrea Trucchia, Mirko D'Andrea, Giorgio Meschi, Silvia degli Esposti, and Paolo Fiorucci

A change in wildfire regimes in several regions around the Earth has been acknowledged in recent decades, with an increase in the frequency of particularly severe events. Consequently, many wildfires management systems have been challenged, renewing interest in Forest Fire Danger Rating (FFDR) models to support preparedness and response phases. The Liguria Region (Italy) and the Italian Civil Protection supported independent research programs that led in 2003 to the development of the FFDR model RISICO. Nowadays the model is used as a decision-support tool by Italian civil protection systems at national and regional levels. RISICO model integrates weather conditions with vegetation types, topography, vegetation indices from satellite and ML-based wildfires susceptibility maps, in order to provide all information available.

One of the main component of RISICO is the Fine Fuel Moisture Content (FFMC) model. Indeed, fine fuel moisture conditions influence the ignition and spread of wildfires, and particularly low FFMC values are often associated with the occurrence of severe events. A new formulation of the FFMC model has therefore been performed to increase its forecasting capabilities and the abilities to discriminate severe wildfire conditions. The FFMC model depends on vegetation types, differentiating the fine fuel moisture behavior through a different response time to weather conditions. This aspect makes it possible to consider the structural peculiarities of each vegetation type, differentiating then forest fire fire risk behavior. The model is also able to simulate fine fuel moisture content at different temporal resolution, ranging from hours to minutes. This makes it possible to describe in detail the fast dynamics of FFMC, which is of particular interest in environments characterized by a rapidly changing forest fire risk such as the Mediterranean environment. A reformulation and parameters calibration of the FFMC model has then been performed, to increase the reliability of the model. The use of the revised FFMC model to simulate moisture conditions in case of wildfires occurred in Italy in the last 15 years shows an increase in the model's ability to discriminate against severe events, characterized by particularly low fine fuel moisture values.

 

How to cite: Perello, N., Trucchia, A., D'Andrea, M., Meschi, G., degli Esposti, S., and Fiorucci, P.: A Tailored Fine Fuel Moisture Content Model for Improving Wildfire Danger Rating Systems, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-14313, https://doi.org/10.5194/egusphere-egu23-14313, 2023.

Posters virtual: Fri, 28 Apr, 10:45–12:30 | vHall SSS

The posters scheduled for virtual presentation are visible in Gather.Town. Attendees are asked to meet the authors during the scheduled attendance time for live video chats. If authors uploaded their presentation files, these files are also linked from the abstracts below, but only on the day of the poster session. The button to access Gather.Town appears just before the time block starts.
Chairperson: Ana Rita Lopes
vSSS.6
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EGU23-15243
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SSS9.11
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Sabino Maggi, Maria Patrizia Adamo, Silvana Fuina, Cristina Tarantino, and Saverio Vicario

The risk of wildfires has risen significantly in recent years, not just in Europe but around the world. In Italy alone, hundreds of thousands of hectares are burned each year, resulting in deaths, the destruction of forests and loss of biodiversity, and damage to infrastructure and farms. One way to address this issue is through satellite remote sensing, which is a valuable tool for monitoring and managing fires, assessing risks, surveying and evaluating the damage caused by fires and preparing recovery actions.The objective that the Alta Murgia National Park is pursuing with this project is to gather information on fires that have occurred within the Park area, in order to quickly identify affected areas and aid in their perimeter, characterization and control, and to support the preliminary and timely design of forest restoration efforts, as well as the updating of AIB plans according to legal requirements.

The project aims to develop automated satellite monitoring procedures using Landsat and Sentinel2 imagery to assess the health of forested areas and identify and characterize degradation caused by negative events such as forest fires, illegal logging, conversion of forest land to agriculture, and improper use of areas historically affected by fire. A module based on difference in the Normalized Burn Ratio (NBR) index would allow to define the effective perimeter of damage caused by a fire within the larger perimeter defined by firefighting crews. Additionally, a module using various vegetation indices, such as those related to chlorophyll and carotenoids, will be employed to compare vegetation changes across the landscape and over time.

The project also involves using a time series analysis to retrospectively monitor the recovery of vegetation following a critical event, and a Bayesian approach previously developed by the group will be used to estimate expected phenological statistics with associated error. To further understand the recovery process, a single forested site burned in 2020 will be closely monitored with an eddy covariance tower and through repeated floristic surveys.

Lastly, the project aims to establish a pilot low-cost ground-based monitoring and video surveillance system to supplement the existing video surveillance network. This system will focus on monitoring remote or less frequented areas of the park, where installing high-end monitoring stations would not be cost-effective. The system proposed is self-sufficient in terms of power and is capable of performing real-time image analysis over the study area. In the event of a fire or the emission of harmful gases, the system will immediately alert relevant law enforcement agencies.
The current work summarizes the current state of the project and the scientific results obtained so far.

How to cite: Maggi, S., Adamo, M. P., Fuina, S., Tarantino, C., and Vicario, S.: Forest Monitoring: Fires and Recovery in Alta Murgia: the MOIRA Project, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-15243, https://doi.org/10.5194/egusphere-egu23-15243, 2023.