Pub Date : 2023-10-02DOI: 10.1186/s42408-023-00212-4
Rodrigo San Martín, Catherine Ottlé, Anna Sörensson
Abstract Background Wildfires represent an important element in the bio-geophysical cycles of various ecosystems across the globe and are particularly related to land transformation in tropical and subtropical regions. In this study, we analyzed the links between fires, land use (LU), and meteorological variables in the South American Chaco (1.1 million km 2 ), a global deforestation hotspot and fire-exposed region that has recently attracted greater attention as the largest and one of the last tropical dry forests in the world. Results We found that the Dry Chaco (73% of the total area of Chaco) exhibits a unimodal fire seasonality (winter-spring), and the Wet Chaco (the remaining 23%) displays a bimodal seasonality (summer-autumn and winter-spring). While most of the burnt area (BA) was found in the Wet Chaco (113,859 km 2 ; 55% of the entire BA), the Dry Chaco showed the largest fraction of forest loss (93,261 km 2 ; 88% of the entire forest loss). Between 2001 and 2019, 26% of the entire Chaco’s forest loss occurred in areas with BA detections, and this percentage varies regionally and across countries, revealing potential connections to LU and policy. Argentina lost 51,409 km 2 of its Chaco tree cover, surpassing the forest losses of Paraguay and Bolivia, and 40% of this loss was related to fire detections. The effect of meteorological fluctuations on fuel production and flammability varies with land cover (LC), which emerged as the principal factor behind BA. While wet areas covered with herbaceous vegetation showed negative correlations between BA and precipitation, some dry regions below 800 mm/year, and mostly covered by shrublands, showed positive correlations. These results reveal the two different roles of precipitation in (a) moisture content and flammability and (b) production of biomass fuel. Conclusions As fires and deforestation keep expanding in the South American Chaco, our study represents a step forward to understanding their drivers and effects. BA is dependent on LC types, which explains the discrepancies in fire frequency and seasonality between the Wet and Dry Chaco subregions. The links between fires and deforestation also vary between regions and between countries, exposing the role of anthropic forcing, land management, and policy. To better understand the interactions between these drivers, further studies at regional scale combining environmental sciences with social sciences are needed. Such research should help policy makers take action to preserve and protect the remaining forests and wetlands of the Chaco.
野火是全球各种生态系统生物地球物理循环的重要组成部分,尤其与热带和亚热带地区的土地转化有关。在这项研究中,我们分析了南美洲查科(110万平方公里)的火灾、土地利用(LU)和气象变量之间的联系,查科是全球森林砍伐热点和火灾暴露地区,最近作为世界上最大和最后的热带干燥森林之一而引起了更大的关注。结果查科干区(占查科总面积的73%)表现为单峰性(冬春),湿区(占查科总面积的23%)表现为双峰性(夏秋和冬春)。而大部分燃烧面积(BA)发现在湿查科(113,859 km 2;占整个BA的55%),干查科的森林损失比例最大(93,261 km2;整个森林损失的88%)。2001年至2019年期间,查科整个森林损失的26%发生在发现BA的地区,这一比例因地区和国家而异,揭示了与LU和政策的潜在联系。阿根廷损失了51,409平方公里的查科树木覆盖面积,超过了巴拉圭和玻利维亚的森林损失,其中40%的损失与火灾探测有关。气象波动对燃料产量和可燃性的影响随土地覆盖(LC)的变化而变化,这是BA背后的主要因素。草本植被覆盖的湿润地区BA与降水呈负相关,而在800mm /年以下以灌丛为主的干旱地区BA与降水呈正相关。这些结果揭示了降水在(a)含水量和可燃性以及(b)生物质燃料生产中的两种不同作用。随着南美查科地区的火灾和森林砍伐不断扩大,我们的研究代表了了解其驱动因素和影响的一步。BA依赖于LC类型,这解释了干湿查科分区之间火灾频率和季节性的差异。火灾和森林砍伐之间的联系也因地区和国家而异,暴露了人为强迫、土地管理和政策的作用。为了更好地理解这些驱动因素之间的相互作用,需要进一步在区域尺度上进行环境科学与社会科学相结合的研究。这样的研究应该有助于决策者采取行动来保存和保护查科剩余的森林和湿地。
{"title":"Fires in the South American Chaco, from dry forests to wetlands: response to climate depends on land cover","authors":"Rodrigo San Martín, Catherine Ottlé, Anna Sörensson","doi":"10.1186/s42408-023-00212-4","DOIUrl":"https://doi.org/10.1186/s42408-023-00212-4","url":null,"abstract":"Abstract Background Wildfires represent an important element in the bio-geophysical cycles of various ecosystems across the globe and are particularly related to land transformation in tropical and subtropical regions. In this study, we analyzed the links between fires, land use (LU), and meteorological variables in the South American Chaco (1.1 million km 2 ), a global deforestation hotspot and fire-exposed region that has recently attracted greater attention as the largest and one of the last tropical dry forests in the world. Results We found that the Dry Chaco (73% of the total area of Chaco) exhibits a unimodal fire seasonality (winter-spring), and the Wet Chaco (the remaining 23%) displays a bimodal seasonality (summer-autumn and winter-spring). While most of the burnt area (BA) was found in the Wet Chaco (113,859 km 2 ; 55% of the entire BA), the Dry Chaco showed the largest fraction of forest loss (93,261 km 2 ; 88% of the entire forest loss). Between 2001 and 2019, 26% of the entire Chaco’s forest loss occurred in areas with BA detections, and this percentage varies regionally and across countries, revealing potential connections to LU and policy. Argentina lost 51,409 km 2 of its Chaco tree cover, surpassing the forest losses of Paraguay and Bolivia, and 40% of this loss was related to fire detections. The effect of meteorological fluctuations on fuel production and flammability varies with land cover (LC), which emerged as the principal factor behind BA. While wet areas covered with herbaceous vegetation showed negative correlations between BA and precipitation, some dry regions below 800 mm/year, and mostly covered by shrublands, showed positive correlations. These results reveal the two different roles of precipitation in (a) moisture content and flammability and (b) production of biomass fuel. Conclusions As fires and deforestation keep expanding in the South American Chaco, our study represents a step forward to understanding their drivers and effects. BA is dependent on LC types, which explains the discrepancies in fire frequency and seasonality between the Wet and Dry Chaco subregions. The links between fires and deforestation also vary between regions and between countries, exposing the role of anthropic forcing, land management, and policy. To better understand the interactions between these drivers, further studies at regional scale combining environmental sciences with social sciences are needed. Such research should help policy makers take action to preserve and protect the remaining forests and wetlands of the Chaco.","PeriodicalId":12273,"journal":{"name":"Fire Ecology","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135895116","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-09-27DOI: 10.1186/s42408-023-00209-z
Suzanne H. Blaydes, Jeffery B. Cannon, Doug P. Aubrey
Abstract Background Predicting patterns of fire behavior and effects in frequent fire forests relies on an understanding of fine-scale spatial patterns of available fuels. Leaf litter is a significant canopy-derived fine fuel in fire-maintained forests. Litter dispersal is dependent on foliage production, stand structure, and wind direction, but the relative importance of these factors is unknown. Results Using a 10-year litterfall dataset collected within eighteen 4-ha longleaf pine ( Pinus palustris Mill.) plots varying in canopy spatial pattern, we compared four spatially explicit models of annual needle litter dispersal: a model based only on basal area, an overstory abundance index (OAI) model, both isotropic and anisotropic litter kernel models, and a null model that assumed no spatial relationship. The best model was the anisotropic model (R 2 = 0.656) that incorporated tree size, location, and prevailing wind direction, followed by the isotropic model (R 2 = 0.612), basal area model (R 2 = 0.488), OAI model (R 2 = 0.416), and the null model (R 2 = 0.08). Conclusions As with previous studies, the predictive capability of the litter models was robust when internally validated with a subset of the original dataset (R 2 = 0.196–0.549); however, the models were less robust when challenged with an independent dataset (R 2 = 0.122–0.319) from novel forest stands. Our model validation underscores the need for rigorous tests with independent, external datasets to confirm the validity of litter dispersal models. These models can be used in the application of prescribed fire to estimate fuel distribution and loading, as well as aid in the fine tuning of fire behavior models to better understand fire outcomes across a range of forest canopy structures.
{"title":"Modeling spatial patterns of longleaf pine needle dispersal using long-term data","authors":"Suzanne H. Blaydes, Jeffery B. Cannon, Doug P. Aubrey","doi":"10.1186/s42408-023-00209-z","DOIUrl":"https://doi.org/10.1186/s42408-023-00209-z","url":null,"abstract":"Abstract Background Predicting patterns of fire behavior and effects in frequent fire forests relies on an understanding of fine-scale spatial patterns of available fuels. Leaf litter is a significant canopy-derived fine fuel in fire-maintained forests. Litter dispersal is dependent on foliage production, stand structure, and wind direction, but the relative importance of these factors is unknown. Results Using a 10-year litterfall dataset collected within eighteen 4-ha longleaf pine ( Pinus palustris Mill.) plots varying in canopy spatial pattern, we compared four spatially explicit models of annual needle litter dispersal: a model based only on basal area, an overstory abundance index (OAI) model, both isotropic and anisotropic litter kernel models, and a null model that assumed no spatial relationship. The best model was the anisotropic model (R 2 = 0.656) that incorporated tree size, location, and prevailing wind direction, followed by the isotropic model (R 2 = 0.612), basal area model (R 2 = 0.488), OAI model (R 2 = 0.416), and the null model (R 2 = 0.08). Conclusions As with previous studies, the predictive capability of the litter models was robust when internally validated with a subset of the original dataset (R 2 = 0.196–0.549); however, the models were less robust when challenged with an independent dataset (R 2 = 0.122–0.319) from novel forest stands. Our model validation underscores the need for rigorous tests with independent, external datasets to confirm the validity of litter dispersal models. These models can be used in the application of prescribed fire to estimate fuel distribution and loading, as well as aid in the fine tuning of fire behavior models to better understand fire outcomes across a range of forest canopy structures.","PeriodicalId":12273,"journal":{"name":"Fire Ecology","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135535485","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-09-25DOI: 10.1186/s42408-023-00206-2
Kristin Sweeney, Ruth Dittrich, Spencer Moffat, Chelsea Power, Jeffrey D. Kline
Abstract Background Wildfires are increasingly frequent in the Western US and impose a number of costs including from the instantaneous release of carbon when vegetation burns. Carbon released into the atmosphere aggravates climate change while carbon stored in vegetation helps to mitigate climate change. The need for climate change mitigation is becoming more and more urgent as achieving the Paris climate agreement target of limiting global warming to 1.5 °C seems ever more challenging. A clear understanding of the role of different carbon sources is required for understanding the degree of progress toward meeting mitigation objectives and assessing the cost and benefits of mitigation policies. Results We present an easily replicable approach to calculate the economic cost from carbon released instantaneously from wildfires at state and county level (US). Our approach is straightforward and relies exclusively on publicly available data that can be easily obtained for locations throughout the USA. We also describe how to apply social cost of carbon estimates to the carbon loss estimates to find the economic value of carbon released from wildfires. We demonstrate our approach using a case study of the 2017 Eagle Creek Fire in Oregon. Our estimated value of carbon lost for this medium-sized (19,400 ha) fire is $187.2 million (2020 dollars), which highlights the significant role that wildfires can have in terms of carbon emissions and their associated cost. The emissions from this fire were equivalent to as much as 2.3% of non-fire emissions for the state of Oregon in 2020. Conclusions Our results demonstrate an easily replicable method for estimating the economic cost of instantaneous carbon dioxide emissions for individual wildfires. Estimates of the potential economic costs associated with carbon dioxide emissions help to provide a more complete picture of the true economic costs of wildfires, thus facilitating a more complete picture of the potential benefits of wildfire management efforts.
{"title":"Estimating the economic value of carbon losses from wildfires using publicly available data sources: Eagle Creek Fire, Oregon 2017","authors":"Kristin Sweeney, Ruth Dittrich, Spencer Moffat, Chelsea Power, Jeffrey D. Kline","doi":"10.1186/s42408-023-00206-2","DOIUrl":"https://doi.org/10.1186/s42408-023-00206-2","url":null,"abstract":"Abstract Background Wildfires are increasingly frequent in the Western US and impose a number of costs including from the instantaneous release of carbon when vegetation burns. Carbon released into the atmosphere aggravates climate change while carbon stored in vegetation helps to mitigate climate change. The need for climate change mitigation is becoming more and more urgent as achieving the Paris climate agreement target of limiting global warming to 1.5 °C seems ever more challenging. A clear understanding of the role of different carbon sources is required for understanding the degree of progress toward meeting mitigation objectives and assessing the cost and benefits of mitigation policies. Results We present an easily replicable approach to calculate the economic cost from carbon released instantaneously from wildfires at state and county level (US). Our approach is straightforward and relies exclusively on publicly available data that can be easily obtained for locations throughout the USA. We also describe how to apply social cost of carbon estimates to the carbon loss estimates to find the economic value of carbon released from wildfires. We demonstrate our approach using a case study of the 2017 Eagle Creek Fire in Oregon. Our estimated value of carbon lost for this medium-sized (19,400 ha) fire is $187.2 million (2020 dollars), which highlights the significant role that wildfires can have in terms of carbon emissions and their associated cost. The emissions from this fire were equivalent to as much as 2.3% of non-fire emissions for the state of Oregon in 2020. Conclusions Our results demonstrate an easily replicable method for estimating the economic cost of instantaneous carbon dioxide emissions for individual wildfires. Estimates of the potential economic costs associated with carbon dioxide emissions help to provide a more complete picture of the true economic costs of wildfires, thus facilitating a more complete picture of the potential benefits of wildfire management efforts.","PeriodicalId":12273,"journal":{"name":"Fire Ecology","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135770912","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-09-20DOI: 10.1186/s42408-023-00216-0
Khubab Ahmad, Muhammad Shahbaz Khan, Fawad Ahmed, Maha Driss, Wadii Boulila, Abdulwahab Alazeb, Mohammad Alsulami, Mohammed S. Alshehri, Yazeed Yasin Ghadi, Jawad Ahmad
Abstract Background Forests cover nearly one-third of the Earth’s land and are some of our most biodiverse ecosystems. Due to climate change, these essential habitats are endangered by increasing wildfires. Wildfires are not just a risk to the environment, but they also pose public health risks. Given these issues, there is an indispensable need for efficient and early detection methods. Conventional detection approaches fall short due to spatial limitations and manual feature engineering, which calls for the exploration and development of data-driven deep learning solutions. This paper, in this regard, proposes 'FireXnet', a tailored deep learning model designed for improved efficiency and accuracy in wildfire detection. FireXnet is tailored to have a lightweight architecture that exhibits high accuracy with significantly less training and testing time. It contains considerably reduced trainable and non-trainable parameters, which makes it suitable for resource-constrained devices. To make the FireXnet model visually explainable and trustable, a powerful explainable artificial intelligence (AI) tool, SHAP (SHapley Additive exPlanations) has been incorporated. It interprets FireXnet’s decisions by computing the contribution of each feature to the prediction. Furthermore, the performance of FireXnet is compared against five pre-trained models — VGG16, InceptionResNetV2, InceptionV3, DenseNet201, and MobileNetV2 — to benchmark its efficiency. For a fair comparison, transfer learning and fine-tuning have been applied to the aforementioned models to retrain the models on our dataset. Results The test accuracy of the proposed FireXnet model is 98.42%, which is greater than all other models used for comparison. Furthermore, results of reliability parameters confirm the model’s reliability, i.e., a confidence interval of [0.97, 1.00] validates the certainty of the proposed model’s estimates and a Cohen’s kappa coefficient of 0.98 proves that decisions of FireXnet are in considerable accordance with the given data. Conclusion The integration of the robust feature extraction of FireXnet with the transparency of explainable AI using SHAP enhances the model’s interpretability and allows for the identification of key characteristics triggering wildfire detections. Extensive experimentation reveals that in addition to being accurate, FireXnet has reduced computational complexity due to considerably fewer training and non-training parameters and has significantly fewer training and testing times.
{"title":"FireXnet: an explainable AI-based tailored deep learning model for wildfire detection on resource-constrained devices","authors":"Khubab Ahmad, Muhammad Shahbaz Khan, Fawad Ahmed, Maha Driss, Wadii Boulila, Abdulwahab Alazeb, Mohammad Alsulami, Mohammed S. Alshehri, Yazeed Yasin Ghadi, Jawad Ahmad","doi":"10.1186/s42408-023-00216-0","DOIUrl":"https://doi.org/10.1186/s42408-023-00216-0","url":null,"abstract":"Abstract Background Forests cover nearly one-third of the Earth’s land and are some of our most biodiverse ecosystems. Due to climate change, these essential habitats are endangered by increasing wildfires. Wildfires are not just a risk to the environment, but they also pose public health risks. Given these issues, there is an indispensable need for efficient and early detection methods. Conventional detection approaches fall short due to spatial limitations and manual feature engineering, which calls for the exploration and development of data-driven deep learning solutions. This paper, in this regard, proposes 'FireXnet', a tailored deep learning model designed for improved efficiency and accuracy in wildfire detection. FireXnet is tailored to have a lightweight architecture that exhibits high accuracy with significantly less training and testing time. It contains considerably reduced trainable and non-trainable parameters, which makes it suitable for resource-constrained devices. To make the FireXnet model visually explainable and trustable, a powerful explainable artificial intelligence (AI) tool, SHAP (SHapley Additive exPlanations) has been incorporated. It interprets FireXnet’s decisions by computing the contribution of each feature to the prediction. Furthermore, the performance of FireXnet is compared against five pre-trained models — VGG16, InceptionResNetV2, InceptionV3, DenseNet201, and MobileNetV2 — to benchmark its efficiency. For a fair comparison, transfer learning and fine-tuning have been applied to the aforementioned models to retrain the models on our dataset. Results The test accuracy of the proposed FireXnet model is 98.42%, which is greater than all other models used for comparison. Furthermore, results of reliability parameters confirm the model’s reliability, i.e., a confidence interval of [0.97, 1.00] validates the certainty of the proposed model’s estimates and a Cohen’s kappa coefficient of 0.98 proves that decisions of FireXnet are in considerable accordance with the given data. Conclusion The integration of the robust feature extraction of FireXnet with the transparency of explainable AI using SHAP enhances the model’s interpretability and allows for the identification of key characteristics triggering wildfire detections. Extensive experimentation reveals that in addition to being accurate, FireXnet has reduced computational complexity due to considerably fewer training and non-training parameters and has significantly fewer training and testing times.","PeriodicalId":12273,"journal":{"name":"Fire Ecology","volume":"161 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136264032","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-09-19DOI: 10.1186/s42408-023-00214-2
Hope Fillingim, Benjamin O. Knapp, John M. Kabrick, Michael C. Stambaugh, Grant P. Elliott, Daniel C. Dey
Abstract Background Shortleaf pine is a fire-adapted tree species, and prescribed fire is commonly used to increase its regeneration success, improve wildlife habitat, and reach conservation objectives associated with open forest ecosystems. We studied direct effects of heat and smoke on shortleaf pine germination in a greenhouse study and effects of season of burning on the number of new germinants in a field study. Improved understanding of fire effects on shortleaf pine seed and regeneration success can help refine burn prescriptions to better meet specific management objectives. Results Temperatures ≥ 120 °C eliminated germination of shortleaf pine seeds in a greenhouse trial, and exposure of seeds to 60 °C resulted in no reduction in germination compared to the unheated control regardless of duration of exposure. At 80 °C, duration of heat exposure mattered, with exposure for 10 min reducing germination compared to unheated controls. Smoke exposure had no effect on germination. A field experiment showed that fall burns (prior to seedfall) resulted in greater initial germinant counts than early spring burns (after seedfall but before germination) or unburned controls, which both resulted in greater initial germinant counts than late spring burns (after germination). Conclusions Season of prescribed burning can affect the success of shortleaf pine germination. Late spring burning resulted in high mortality of young germinants. Burning in early spring likely resulted in direct damage to some seeds due to heating but may have also had indirect benefit by exposing mineral soil. Fall burning, before the dispersal of shortleaf pine seed, yielded the highest germinant count and is recommended if improving natural regeneration from seed is the primary objective.
{"title":"Direct and indirect effects of fire on germination of shortleaf pine seeds","authors":"Hope Fillingim, Benjamin O. Knapp, John M. Kabrick, Michael C. Stambaugh, Grant P. Elliott, Daniel C. Dey","doi":"10.1186/s42408-023-00214-2","DOIUrl":"https://doi.org/10.1186/s42408-023-00214-2","url":null,"abstract":"Abstract Background Shortleaf pine is a fire-adapted tree species, and prescribed fire is commonly used to increase its regeneration success, improve wildlife habitat, and reach conservation objectives associated with open forest ecosystems. We studied direct effects of heat and smoke on shortleaf pine germination in a greenhouse study and effects of season of burning on the number of new germinants in a field study. Improved understanding of fire effects on shortleaf pine seed and regeneration success can help refine burn prescriptions to better meet specific management objectives. Results Temperatures ≥ 120 °C eliminated germination of shortleaf pine seeds in a greenhouse trial, and exposure of seeds to 60 °C resulted in no reduction in germination compared to the unheated control regardless of duration of exposure. At 80 °C, duration of heat exposure mattered, with exposure for 10 min reducing germination compared to unheated controls. Smoke exposure had no effect on germination. A field experiment showed that fall burns (prior to seedfall) resulted in greater initial germinant counts than early spring burns (after seedfall but before germination) or unburned controls, which both resulted in greater initial germinant counts than late spring burns (after germination). Conclusions Season of prescribed burning can affect the success of shortleaf pine germination. Late spring burning resulted in high mortality of young germinants. Burning in early spring likely resulted in direct damage to some seeds due to heating but may have also had indirect benefit by exposing mineral soil. Fall burning, before the dispersal of shortleaf pine seed, yielded the highest germinant count and is recommended if improving natural regeneration from seed is the primary objective.","PeriodicalId":12273,"journal":{"name":"Fire Ecology","volume":"174 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135010935","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-09-18DOI: 10.1186/s42408-023-00210-6
Belén Luna, Paula Piñas-Bonilla, Gonzalo Zavala, Beatriz Pérez
Abstract Background Mediterranean-type ecosystems are fire-prone environments where species have evolved in the presence of seasonal summer conditions and frequent fires. In these environments, many species have seeds with impermeable hard coats that impose physical seed dormancy which prevents seed germination until it is broken by any factor such as fire or high summer temperatures. Most studies have usually focused on the isolated effects of fire or summer temperatures on the release of physical seed dormancy. However, both factors frequently operate together because when a fire occurs, usually in summer, seeds in the soil suffer not only the heat shock during the fire, but also the high summer temperatures. Nevertheless, the combined effect of both factors is almost unknown. In this investigation, we studied the isolated and combined effects of heat shock and the high temperatures of summer. The main objective was to evaluate whether the timing in which seeds are exposed to a heat shock during the period of high summer temperatures affects seed germination. Results We exposed the seeds of 12 Cistaceae species to three different treatments, in which heat shock (100 °C for 10 min) was applied before, after, or before + after they were exposed to summer temperatures (50/20 °C for 1 month). Although fire was the main factor breaking physical dormancy, its effects were regulated by the timing when it was simulated. We found that summer temperatures following heat shock had negative effects on seed germination since a high proportion of seeds remained dormant. On the contrary, when summer temperatures preceded heat shock, physical dormancy was broken, and germination increased. Conclusions Timing of fire during summer plays an important role in controlling seed germination of Cistaceae. Our results provide a novel explanation for the higher Cistaceae seedling emergence found in the field after late season fires. Additionally, we can carefully draw conclusions for fire management since prescribed burnings would have different effects depending on when they were carried out.
{"title":"Timing of fire during summer determines seed germination in Mediterranean Cistaceae","authors":"Belén Luna, Paula Piñas-Bonilla, Gonzalo Zavala, Beatriz Pérez","doi":"10.1186/s42408-023-00210-6","DOIUrl":"https://doi.org/10.1186/s42408-023-00210-6","url":null,"abstract":"Abstract Background Mediterranean-type ecosystems are fire-prone environments where species have evolved in the presence of seasonal summer conditions and frequent fires. In these environments, many species have seeds with impermeable hard coats that impose physical seed dormancy which prevents seed germination until it is broken by any factor such as fire or high summer temperatures. Most studies have usually focused on the isolated effects of fire or summer temperatures on the release of physical seed dormancy. However, both factors frequently operate together because when a fire occurs, usually in summer, seeds in the soil suffer not only the heat shock during the fire, but also the high summer temperatures. Nevertheless, the combined effect of both factors is almost unknown. In this investigation, we studied the isolated and combined effects of heat shock and the high temperatures of summer. The main objective was to evaluate whether the timing in which seeds are exposed to a heat shock during the period of high summer temperatures affects seed germination. Results We exposed the seeds of 12 Cistaceae species to three different treatments, in which heat shock (100 °C for 10 min) was applied before, after, or before + after they were exposed to summer temperatures (50/20 °C for 1 month). Although fire was the main factor breaking physical dormancy, its effects were regulated by the timing when it was simulated. We found that summer temperatures following heat shock had negative effects on seed germination since a high proportion of seeds remained dormant. On the contrary, when summer temperatures preceded heat shock, physical dormancy was broken, and germination increased. Conclusions Timing of fire during summer plays an important role in controlling seed germination of Cistaceae. Our results provide a novel explanation for the higher Cistaceae seedling emergence found in the field after late season fires. Additionally, we can carefully draw conclusions for fire management since prescribed burnings would have different effects depending on when they were carried out.","PeriodicalId":12273,"journal":{"name":"Fire Ecology","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135202688","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-09-15DOI: 10.1186/s42408-023-00213-3
José M. Moreno, Eva Zuazua, Iván Torres, Antonio Parra, Clara Moreno-Fenoll
Abstract Background Mediterranean shrublands are composed of species that have different regeneration strategies after fire and soil seed bank types. However, differences over the years in seed dispersal temporal and spatial patterns of the various plants composing a community have been little investigated. Here, we studied the temporal and spatial patterns of seed dispersal in four shrubs of an old (> 40 years) shrubland in central Spain. Three of them are seeders ( Cistus ladanifer , Erica umbellata , and Salvia rosmarinus ), and one is a resprouter ( Erica arborea ); the first two have persistent soil seed banks, and the latter two, transient. A 15 × 10 m plot was chosen and divided into a 0.5 × 0.5 m grid, where plant cover and density were measured. At 106 quadrats, seed traps were set and periodically (1–2 monthly) monitored for 3 years. Results S. rosmarinus dispersed in late spring-early summer, E. arborea dispersed during the summer, and C. ladanifer and E. umbellata dispersed from early summer to nearly late spring of the next year. Globally, seeds were being dispersed all year round. The seed crop size of a given species varied between years, although species differed in the year their seed crop was largest, despite large differences in climate. Seed rain and plant cover of each species were poorly related in terms of the variance explained by the models. Semivariogram analysis showed that seed dispersal expanded beyond that of the plant cover of each species by a few meters. No association between seed crop size and spatial dependence was ascertained. While species dispersal in space tended to be negatively related to one another, E. arborea seeds tended to dominate underneath the majority of the other species. Conclusions S. rosmarinus dispersed before the fire season, which is consistent with seeds avoiding fire while on the plant; C. ladanifer and E. umbellata dispersed mostly after the fire season, which is coherent with a bet-hedging strategy against seed predators; E. arborea dispersed before the rainy season, which is expected for a plant that germinates readily after imbibition. Seed dispersal in time was compatible with the type of soil seed bank and post-fire regeneration of the species. The evidence of such a relationship with spatial patterns was weak. The dominance of E. arborea seeds underneath most of the other species suggests that this mid-successional species might dominate when openings form due to the deaths of standing plants of the seeders between two fires, given their lower longevity.
{"title":"Temporal and spatial patterns of seed dispersal of four shrubs in a Cistus-Erica shrubland from central Spain","authors":"José M. Moreno, Eva Zuazua, Iván Torres, Antonio Parra, Clara Moreno-Fenoll","doi":"10.1186/s42408-023-00213-3","DOIUrl":"https://doi.org/10.1186/s42408-023-00213-3","url":null,"abstract":"Abstract Background Mediterranean shrublands are composed of species that have different regeneration strategies after fire and soil seed bank types. However, differences over the years in seed dispersal temporal and spatial patterns of the various plants composing a community have been little investigated. Here, we studied the temporal and spatial patterns of seed dispersal in four shrubs of an old (> 40 years) shrubland in central Spain. Three of them are seeders ( Cistus ladanifer , Erica umbellata , and Salvia rosmarinus ), and one is a resprouter ( Erica arborea ); the first two have persistent soil seed banks, and the latter two, transient. A 15 × 10 m plot was chosen and divided into a 0.5 × 0.5 m grid, where plant cover and density were measured. At 106 quadrats, seed traps were set and periodically (1–2 monthly) monitored for 3 years. Results S. rosmarinus dispersed in late spring-early summer, E. arborea dispersed during the summer, and C. ladanifer and E. umbellata dispersed from early summer to nearly late spring of the next year. Globally, seeds were being dispersed all year round. The seed crop size of a given species varied between years, although species differed in the year their seed crop was largest, despite large differences in climate. Seed rain and plant cover of each species were poorly related in terms of the variance explained by the models. Semivariogram analysis showed that seed dispersal expanded beyond that of the plant cover of each species by a few meters. No association between seed crop size and spatial dependence was ascertained. While species dispersal in space tended to be negatively related to one another, E. arborea seeds tended to dominate underneath the majority of the other species. Conclusions S. rosmarinus dispersed before the fire season, which is consistent with seeds avoiding fire while on the plant; C. ladanifer and E. umbellata dispersed mostly after the fire season, which is coherent with a bet-hedging strategy against seed predators; E. arborea dispersed before the rainy season, which is expected for a plant that germinates readily after imbibition. Seed dispersal in time was compatible with the type of soil seed bank and post-fire regeneration of the species. The evidence of such a relationship with spatial patterns was weak. The dominance of E. arborea seeds underneath most of the other species suggests that this mid-successional species might dominate when openings form due to the deaths of standing plants of the seeders between two fires, given their lower longevity.","PeriodicalId":12273,"journal":{"name":"Fire Ecology","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135436838","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-08-29DOI: 10.1186/s42408-023-00208-0
Bradley M. Pietruszka, Jesse D. Young, K. Short, Lise A. St. Denis, Matthew P. Thompson, D. Calkin
{"title":"Consequential lightning-caused wildfires and the “let burn” narrative","authors":"Bradley M. Pietruszka, Jesse D. Young, K. Short, Lise A. St. Denis, Matthew P. Thompson, D. Calkin","doi":"10.1186/s42408-023-00208-0","DOIUrl":"https://doi.org/10.1186/s42408-023-00208-0","url":null,"abstract":"","PeriodicalId":12273,"journal":{"name":"Fire Ecology","volume":" ","pages":"1-15"},"PeriodicalIF":5.1,"publicationDate":"2023-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48322805","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-08-24DOI: 10.1186/s42408-023-00207-1
Jessalyn Ayars, R. L. Emmet, S. Bassing, Olivia V. Sanderfoot, Sierra Raby, A. Karambelas, E. James, R. Ahmadov, B. Gardner
{"title":"Camera traps link population-level activity patterns with wildfire smoke events for mammals in Eastern Washington State","authors":"Jessalyn Ayars, R. L. Emmet, S. Bassing, Olivia V. Sanderfoot, Sierra Raby, A. Karambelas, E. James, R. Ahmadov, B. Gardner","doi":"10.1186/s42408-023-00207-1","DOIUrl":"https://doi.org/10.1186/s42408-023-00207-1","url":null,"abstract":"","PeriodicalId":12273,"journal":{"name":"Fire Ecology","volume":" ","pages":"1-15"},"PeriodicalIF":5.1,"publicationDate":"2023-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49248516","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-08-14DOI: 10.1186/s42408-023-00211-5
Harun Jamil, Khan Murad Ali, Do-Hyeun Kim
{"title":"Correction: Federated recognition mechanism based on enhanced temporal-spatial learning using mobile edge sensors for firefighters","authors":"Harun Jamil, Khan Murad Ali, Do-Hyeun Kim","doi":"10.1186/s42408-023-00211-5","DOIUrl":"https://doi.org/10.1186/s42408-023-00211-5","url":null,"abstract":"","PeriodicalId":12273,"journal":{"name":"Fire Ecology","volume":"19 1","pages":"1"},"PeriodicalIF":5.1,"publicationDate":"2023-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49356835","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}