Pub Date : 2024-03-18DOI: 10.1186/s42408-024-00262-2
Izak P. J. Smit, Johan A. Baard, Brian W. van Wilgen
Fire regimes in South African fynbos shrublands have been quantified in the western (winter rainfall) and central (aseasonal rainfall) parts. They have not been quantified at their eastern extremity (summer rainfall), where fynbos transitions to grassland and is embedded in other fire-resistant vegetation types. We assessed fire regimes at the eastern extremity of the fynbos biome and discussed the ecological and management implications of our findings. Using remote sensing, we assessed fires over 21 years in a 350,000-ha study area at the eastern edge of the fynbos biome. Only 9% of the study area burned, almost exclusively in mixed grassland-fynbos vegetation. The largest proportion (44% of the total area burnt) burnt in late winter and early spring, but fires occurred throughout the year. Fires only occurred in 39% of the mixed grassland-fynbos vegetation. Of the mixed grassland-fynbos vegetation that did burn, 44%, 11%, 26%, and 19% experienced one, two, three, and four fires, respectively. Areas with multiple fires had return intervals ranging from 3 to 15 years, with 76% of the area with multiple fires burning every 4 to 6 years. Most large fires were preceded by two relatively dry months, when fuels were drier and more flammable. The mixed grassland-fynbos vegetation at the eastern extremity of the fynbos biome is surrounded by fire-resistant vegetation and exhibits a varied fire regime, with different parts experiencing frequent, infrequent, or no fire over 21 years. Fires were largely aseasonal, occurring throughout the year, although data over more years may reveal that a greater proportion of fires will occur in winter, when grasses are cured and rainfall is low, as well as after relatively long (> 2 months) periods of below-average rainfall. As most fires would burn out safely against fire-resistant vegetation, we conclude that lightning-ignited fires should be allowed to spread unhindered to approximate a natural and heterogeneous fire regime, provided that no neighboring properties or infrastructure are threatened. The response of the biota to fires is not well understood for this transition area, and further research is needed.
{"title":"Fire regimes and management options in mixed grassland-fynbos vegetation, South Africa","authors":"Izak P. J. Smit, Johan A. Baard, Brian W. van Wilgen","doi":"10.1186/s42408-024-00262-2","DOIUrl":"https://doi.org/10.1186/s42408-024-00262-2","url":null,"abstract":"Fire regimes in South African fynbos shrublands have been quantified in the western (winter rainfall) and central (aseasonal rainfall) parts. They have not been quantified at their eastern extremity (summer rainfall), where fynbos transitions to grassland and is embedded in other fire-resistant vegetation types. We assessed fire regimes at the eastern extremity of the fynbos biome and discussed the ecological and management implications of our findings. Using remote sensing, we assessed fires over 21 years in a 350,000-ha study area at the eastern edge of the fynbos biome. Only 9% of the study area burned, almost exclusively in mixed grassland-fynbos vegetation. The largest proportion (44% of the total area burnt) burnt in late winter and early spring, but fires occurred throughout the year. Fires only occurred in 39% of the mixed grassland-fynbos vegetation. Of the mixed grassland-fynbos vegetation that did burn, 44%, 11%, 26%, and 19% experienced one, two, three, and four fires, respectively. Areas with multiple fires had return intervals ranging from 3 to 15 years, with 76% of the area with multiple fires burning every 4 to 6 years. Most large fires were preceded by two relatively dry months, when fuels were drier and more flammable. The mixed grassland-fynbos vegetation at the eastern extremity of the fynbos biome is surrounded by fire-resistant vegetation and exhibits a varied fire regime, with different parts experiencing frequent, infrequent, or no fire over 21 years. Fires were largely aseasonal, occurring throughout the year, although data over more years may reveal that a greater proportion of fires will occur in winter, when grasses are cured and rainfall is low, as well as after relatively long (> 2 months) periods of below-average rainfall. As most fires would burn out safely against fire-resistant vegetation, we conclude that lightning-ignited fires should be allowed to spread unhindered to approximate a natural and heterogeneous fire regime, provided that no neighboring properties or infrastructure are threatened. The response of the biota to fires is not well understood for this transition area, and further research is needed.","PeriodicalId":12273,"journal":{"name":"Fire Ecology","volume":"69 1","pages":""},"PeriodicalIF":5.1,"publicationDate":"2024-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140155037","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 : 2024-03-15DOI: 10.1186/s42408-024-00261-3
Elliott T. Conrad, W. Matt Jolly, Tegan P. Brown, Samuel C. Hillman
Accurate estimates of available live crown fuel loads are critical for understanding potential wildland fire behavior. Existing crown fire behavior models assume that available crown fuels are limited to all tree foliage and half of the fine branches less than 6 mm in diameter (1 h fuel). They also assume that this relationship is independent of the branchwood moisture content. Despite their widespread use, these assumptions have never been tested, and our understanding of the physiochemical properties that govern live crown flammability and consumption remains limited. To test these assumptions, we sampled branches from 11 common Intermountain West USA conifers and determined the corrected available fuel estimates using physiochemical measurements, diameter subsize class distributions, and a bench-scale consumption experiment. Additional branches were air-dried to explore interaction between moisture content and consumption. Corrected available live crown fuel was compared to existing models across species and then used to determine potential differences in crown fire energy release. Across the 11 common conifers, distinct patterns of sub 1 h fuel distributions were strong predictors of whether the existing available live crown fuel models overestimated, approximately correctly estimated, or underestimated available live fuel. Fine branchwood distributions generally fell into three archetypes: fine skewed, normally distributed, and coarse skewed. Based on our corrected estimates, existing models overestimated the potential canopy energy by 34% for an average-sized western larch and underestimated it by 18.8% for western hemlock. The critical fine branchwood consumption diameter varied with species and moisture content. Larger proportions of fine branches were consumed as the branchwood dried, and nearly all the 1 h fuel was consumed when the branches were completely dry. These results suggest that available live canopy fuel load estimates should consider species and moisture content to accurately assess and map fuel loads across landscapes. This work has implications for forest and fire management in conifer-dominated forests throughout western North America, and in other similar forests worldwide.
准确估算可用的活树冠燃料负荷对于了解潜在的野地火灾行为至关重要。现有的树冠火灾行为模型假定可用的树冠燃料仅限于所有树叶和直径小于 6 毫米的一半细枝(1 h 燃料)。它们还假设这种关系与枝木含水量无关。尽管这些假设被广泛使用,但从未经过测试,我们对控制活树冠可燃性和消耗的理化特性的了解仍然有限。为了验证这些假设,我们从 11 种常见的美国西部山间针叶树的树枝上取样,并利用理化测量、直径亚尺寸等级分布和台架规模的消耗实验确定了修正后的可用燃料估算值。还对其他树枝进行了风干,以探索水分含量与消耗量之间的相互作用。修正后的活树冠可用燃料与各树种的现有模型进行了比较,然后用于确定树冠火灾能量释放的潜在差异。在 11 种常见针叶树中,1 h 以下燃料分布的不同模式是现有可用活冠燃料模型高估、近似正确估计或低估可用活燃料的有力预测因素。细枝木分布一般分为三种原型:细斜分布、正态分布和粗斜分布。根据我们的修正估计,现有模型对平均大小的西部落叶松的树冠潜在能量高估了 34%,对西部铁杉则低估了 18.8%。临界细枝木消耗直径因树种和含水率而异。随着枝干的干燥,细枝被消耗的比例越来越大,当枝干完全干燥时,几乎所有的 1 h 燃料都被消耗掉了。这些结果表明,现有的活树冠燃料负荷估算应考虑树种和含水量,以准确评估和绘制整个地貌的燃料负荷图。这项工作对北美西部针叶林为主的森林以及全球其他类似森林的森林和火灾管理具有重要意义。
{"title":"Branching out: species-specific canopy architecture limits live crown fuel consumption in Intermountain West USA conifers","authors":"Elliott T. Conrad, W. Matt Jolly, Tegan P. Brown, Samuel C. Hillman","doi":"10.1186/s42408-024-00261-3","DOIUrl":"https://doi.org/10.1186/s42408-024-00261-3","url":null,"abstract":"Accurate estimates of available live crown fuel loads are critical for understanding potential wildland fire behavior. Existing crown fire behavior models assume that available crown fuels are limited to all tree foliage and half of the fine branches less than 6 mm in diameter (1 h fuel). They also assume that this relationship is independent of the branchwood moisture content. Despite their widespread use, these assumptions have never been tested, and our understanding of the physiochemical properties that govern live crown flammability and consumption remains limited. To test these assumptions, we sampled branches from 11 common Intermountain West USA conifers and determined the corrected available fuel estimates using physiochemical measurements, diameter subsize class distributions, and a bench-scale consumption experiment. Additional branches were air-dried to explore interaction between moisture content and consumption. Corrected available live crown fuel was compared to existing models across species and then used to determine potential differences in crown fire energy release. Across the 11 common conifers, distinct patterns of sub 1 h fuel distributions were strong predictors of whether the existing available live crown fuel models overestimated, approximately correctly estimated, or underestimated available live fuel. Fine branchwood distributions generally fell into three archetypes: fine skewed, normally distributed, and coarse skewed. Based on our corrected estimates, existing models overestimated the potential canopy energy by 34% for an average-sized western larch and underestimated it by 18.8% for western hemlock. The critical fine branchwood consumption diameter varied with species and moisture content. Larger proportions of fine branches were consumed as the branchwood dried, and nearly all the 1 h fuel was consumed when the branches were completely dry. These results suggest that available live canopy fuel load estimates should consider species and moisture content to accurately assess and map fuel loads across landscapes. This work has implications for forest and fire management in conifer-dominated forests throughout western North America, and in other similar forests worldwide.","PeriodicalId":12273,"journal":{"name":"Fire Ecology","volume":"22 1","pages":""},"PeriodicalIF":5.1,"publicationDate":"2024-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140155012","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}
The Panxi region in China is among the areas that are most severely impacted by forest fires. Despite this, there is currently a lack of comprehensive and systematic research on the spatial and temporal distribution patterns, as well as the drivers, of forest fires in the region. To reveal bio-geo-climatic and anthropogenic influences, this study investigated the temporal and spatial characteristics of forest fires and migration patterns of the center of gravity of forest fires in Panxi. A parametric optimal geographical detection model was utilized to quantify the influence of various individual factors and their combinations on the spatial patterns of forest fire occurrence in the whole Panxi region and sub-region, by analyzing the forest fire dataset from 2004 to 2020. From 2004 to 2020, the Panxi region experienced an upward trend in the number of forest fires and the area burned. However, the trends were not consistent over the entire period. Between 2004 and 2014, both the number of fires and the area burned showed fluctuations and an overall increase. In contrast, between 2015 and 2020, there was a significant decrease in the number of fires, while the area burned showed a continued upward trend. The study identified abrupt changes in the frequency of forest fires and burned areas, primarily in 2007 and 2016. Spatially, forest fires in Panxi exhibited a positive correlation and local clustering. The river valley basin and hilly regions displayed a higher incidence of forest fires, which were concentrated mainly along the hill edges. In the whole area of Panxi, climatic factors have a predominant influence on forest fire occurrences. Specifically, evaporation, maximum temperature, average temperature, number of days without rain, and minimum temperature demonstrated the strongest explanatory power. Furthermore, this relationship was found to be reinforced when combined with topographical, human activities, and vegetation factors. The spatial variation of drought within each sub-district has a stronger explanatory power for the distribution characteristics of forest fires in the region than at the Panxi-wide scale. The factor with the maximum interaction in most regions was the dual factor of rainfall and drought. The study’s findings validate the applicability of geographic probes for identifying the drivers of fire occurrence and enhance our understanding of the drivers and their combined effects on the spatial context of the fire-incident study area.
{"title":"Spatial and temporal patterns and driving factors of forest fires based on an optimal parameter-based geographic detector in the Panxi region, Southwest China","authors":"Jia Liu, Yukuan Wang, Haiyan Guo, Yafeng Lu, Yuanxin Xu, Yu Sun, Weiwei Gan, Rui Sun, Zhengyang Li","doi":"10.1186/s42408-024-00257-z","DOIUrl":"https://doi.org/10.1186/s42408-024-00257-z","url":null,"abstract":"The Panxi region in China is among the areas that are most severely impacted by forest fires. Despite this, there is currently a lack of comprehensive and systematic research on the spatial and temporal distribution patterns, as well as the drivers, of forest fires in the region. To reveal bio-geo-climatic and anthropogenic influences, this study investigated the temporal and spatial characteristics of forest fires and migration patterns of the center of gravity of forest fires in Panxi. A parametric optimal geographical detection model was utilized to quantify the influence of various individual factors and their combinations on the spatial patterns of forest fire occurrence in the whole Panxi region and sub-region, by analyzing the forest fire dataset from 2004 to 2020. From 2004 to 2020, the Panxi region experienced an upward trend in the number of forest fires and the area burned. However, the trends were not consistent over the entire period. Between 2004 and 2014, both the number of fires and the area burned showed fluctuations and an overall increase. In contrast, between 2015 and 2020, there was a significant decrease in the number of fires, while the area burned showed a continued upward trend. The study identified abrupt changes in the frequency of forest fires and burned areas, primarily in 2007 and 2016. Spatially, forest fires in Panxi exhibited a positive correlation and local clustering. The river valley basin and hilly regions displayed a higher incidence of forest fires, which were concentrated mainly along the hill edges. In the whole area of Panxi, climatic factors have a predominant influence on forest fire occurrences. Specifically, evaporation, maximum temperature, average temperature, number of days without rain, and minimum temperature demonstrated the strongest explanatory power. Furthermore, this relationship was found to be reinforced when combined with topographical, human activities, and vegetation factors. The spatial variation of drought within each sub-district has a stronger explanatory power for the distribution characteristics of forest fires in the region than at the Panxi-wide scale. The factor with the maximum interaction in most regions was the dual factor of rainfall and drought. The study’s findings validate the applicability of geographic probes for identifying the drivers of fire occurrence and enhance our understanding of the drivers and their combined effects on the spatial context of the fire-incident study area.","PeriodicalId":12273,"journal":{"name":"Fire Ecology","volume":"1 1","pages":""},"PeriodicalIF":5.1,"publicationDate":"2024-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140155370","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 : 2024-03-14DOI: 10.1186/s42408-024-00256-0
Roxane Andersen, Paula Fernandez-Garcia, Alice Martin-Walker, Daniela Klein, Chris Marshall, David J. Large, Robert Hughes, Mark H. Hancock
In 2019, a wildfire impacted an area of blanket bog and wet heath > 60 km2 in the Flow Country peatlands of northern Scotland, a site of global significance. Unusually the footprint of the wildfire included discrete areas of degraded, restored, and near-natural blanket bogs. Following the wildfire, we surveyed vegetation in 387 quadrats in burnt and unburnt areas. The study aimed to determine whether and how proximity to human-made drains and microtopography affected fire-vegetation interactions and included older wildfire sites and unburnt control sites for context. Overall, our study suggests that the 2019 Flow Country wildfire caused mostly superficial burning; except in the most degraded area, which burned more severely and where we recorded more profound impacts on the vegetation. We found higher cover of litter, which in turn led to increased localized fire damage in quadrats close to drains compared with quadrats away from the influence of drains. We also found greater fire impacts (e.g., proportions of moss burnt and Sphagnum discoloration) on hummocks, particularly where they were higher relative to the hollows. Overall, vegetation both near and away from drains largely resembled nearby unburnt sites within 20 years. Overall, our study suggests that the 2019 Flow Country wildfire caused mostly superficial burning, except in the most degraded areas. Vegetation communities of blanket bogs associated with conservation and restoration areas in the region appear to be largely resilient to occasional, low severity wildfires. This implies that management interventions that maintain wet conditions in peatlands have the potential to help reduce the risks of severe wildfires.
{"title":"Blanket bog vegetation response to wildfire and drainage suggests resilience to low severity, infrequent burning","authors":"Roxane Andersen, Paula Fernandez-Garcia, Alice Martin-Walker, Daniela Klein, Chris Marshall, David J. Large, Robert Hughes, Mark H. Hancock","doi":"10.1186/s42408-024-00256-0","DOIUrl":"https://doi.org/10.1186/s42408-024-00256-0","url":null,"abstract":"In 2019, a wildfire impacted an area of blanket bog and wet heath > 60 km2 in the Flow Country peatlands of northern Scotland, a site of global significance. Unusually the footprint of the wildfire included discrete areas of degraded, restored, and near-natural blanket bogs. Following the wildfire, we surveyed vegetation in 387 quadrats in burnt and unburnt areas. The study aimed to determine whether and how proximity to human-made drains and microtopography affected fire-vegetation interactions and included older wildfire sites and unburnt control sites for context. Overall, our study suggests that the 2019 Flow Country wildfire caused mostly superficial burning; except in the most degraded area, which burned more severely and where we recorded more profound impacts on the vegetation. We found higher cover of litter, which in turn led to increased localized fire damage in quadrats close to drains compared with quadrats away from the influence of drains. We also found greater fire impacts (e.g., proportions of moss burnt and Sphagnum discoloration) on hummocks, particularly where they were higher relative to the hollows. Overall, vegetation both near and away from drains largely resembled nearby unburnt sites within 20 years. Overall, our study suggests that the 2019 Flow Country wildfire caused mostly superficial burning, except in the most degraded areas. Vegetation communities of blanket bogs associated with conservation and restoration areas in the region appear to be largely resilient to occasional, low severity wildfires. This implies that management interventions that maintain wet conditions in peatlands have the potential to help reduce the risks of severe wildfires.","PeriodicalId":12273,"journal":{"name":"Fire Ecology","volume":"32 1","pages":""},"PeriodicalIF":5.1,"publicationDate":"2024-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140129835","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}
Fire is a natural disturbance that significantly impacts ecosystems and plays a crucial role in the distribution and preservation of biota worldwide. The effects of fires on bird diversity can be both positive, as they can create new habitats, and negative, as they can reduce nesting success. To fully understand the ecological implications of wildfires, we need to understand the spatial distribution of wildland bird diversity and fire regimes and how fire regimes affect wildland bird diversity ecosystems. Using data collected at a global scale, we examined effects of time-averaged fire regimes on the spatial diversity of wildland bird species. Initially, we used the MaxEnt algorithm to model the potential distribution of 1,115 wildland bird species over a 20-year period. We also processed satellite observations of burned areas (FIRECCI51) during the same period to estimate fire regime characteristics, including the average proportion of burnt vegetation, interannual variability in the burnt area, and fire intensity. Finally, the association between wild bird diversity and fire variables in each biome was determined through Spearman, Bonferroni, and Kruskal-Wallis statistics. Our findings revealed that (I) the most affected wildland bird communities are those found in tropical ecosystems, where the majority of fires occur; (II) high fire intensity values and a substantial proportion of burned vegetation have a positive impact on maintaining a diverse population of wildland birds in biomes characterized by savannah or grassland covers, as seen in temperate or tropical zones. Conversely, low fire intensity values and a smaller proportion of burned vegetation also promote greater diversity of wildland birds in boreal or temperate zones, and (III) in Mediterranean ecosystems, a clear association between wildland bird diversity and wildfires could not be established. This research could help identify areas that are ecologically vulnerable to wildfires. It could also be useful in guiding regional studies aligned with developing sustainable landscape management practices and conserving priority ecological zones in tropical ecosystems.
{"title":"Global impacts of fire regimes on wildland bird diversity","authors":"Fátima Arrogante-Funes, Inmaculada Aguado, Emilio Chuvieco","doi":"10.1186/s42408-024-00259-x","DOIUrl":"https://doi.org/10.1186/s42408-024-00259-x","url":null,"abstract":"Fire is a natural disturbance that significantly impacts ecosystems and plays a crucial role in the distribution and preservation of biota worldwide. The effects of fires on bird diversity can be both positive, as they can create new habitats, and negative, as they can reduce nesting success. To fully understand the ecological implications of wildfires, we need to understand the spatial distribution of wildland bird diversity and fire regimes and how fire regimes affect wildland bird diversity ecosystems. Using data collected at a global scale, we examined effects of time-averaged fire regimes on the spatial diversity of wildland bird species. Initially, we used the MaxEnt algorithm to model the potential distribution of 1,115 wildland bird species over a 20-year period. We also processed satellite observations of burned areas (FIRECCI51) during the same period to estimate fire regime characteristics, including the average proportion of burnt vegetation, interannual variability in the burnt area, and fire intensity. Finally, the association between wild bird diversity and fire variables in each biome was determined through Spearman, Bonferroni, and Kruskal-Wallis statistics. Our findings revealed that (I) the most affected wildland bird communities are those found in tropical ecosystems, where the majority of fires occur; (II) high fire intensity values and a substantial proportion of burned vegetation have a positive impact on maintaining a diverse population of wildland birds in biomes characterized by savannah or grassland covers, as seen in temperate or tropical zones. Conversely, low fire intensity values and a smaller proportion of burned vegetation also promote greater diversity of wildland birds in boreal or temperate zones, and (III) in Mediterranean ecosystems, a clear association between wildland bird diversity and wildfires could not be established. This research could help identify areas that are ecologically vulnerable to wildfires. It could also be useful in guiding regional studies aligned with developing sustainable landscape management practices and conserving priority ecological zones in tropical ecosystems.","PeriodicalId":12273,"journal":{"name":"Fire Ecology","volume":"8 1","pages":""},"PeriodicalIF":5.1,"publicationDate":"2024-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140124541","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 : 2024-03-08DOI: 10.1186/s42408-024-00253-3
Michael C. Stambaugh, Joseph M. Marschall, Erin R. Abadir, Richard P. Guyette, Daniel C. Dey
Currently, no multiple century fire scar records have been constructed in the Lower Peninsula of Michigan, USA, a region where historical vegetation ranged from prairies and oak-dominated woodlands in the south to conifer-northern hardwood forests and swamps to the north. The western portion of the Huron-Manistee National Forests is located within this strong vegetation transition (i.e., “Tension Zone”) and, based on this study, has well-preserved remnant red pine trees dating back to at least the late 1400s with fire scars dating back to 1523. From fire scar records constructed at four study sites, we documented historical fires as having a wide range of fire intervals and seasonalities. A general timeline of fire activity changes in this region can be described as relatively frequent fire in the pre- and early-European contact eras, variable and generally less fire from this point forward until the period of major logging activities after which fire frequency was significantly increased. Historical fires were associated with drought in the year of fire. Some broad synchronies of fire occurrence existed among sites such as 3 of 4 sites recording fires in years 1717, 1774, and 1829. Interestingly, these years were not exceptionally dry nor among the driest fire years. Future development of fire scar records will likely improve spatio-temporal characterization of regional fire regimes including understanding of human-climate-fire dynamics.
{"title":"Historical fire regimes from red pines (Pinus resinosa Ait.) across the Tension Zone in the Lower Peninsula, Michigan USA","authors":"Michael C. Stambaugh, Joseph M. Marschall, Erin R. Abadir, Richard P. Guyette, Daniel C. Dey","doi":"10.1186/s42408-024-00253-3","DOIUrl":"https://doi.org/10.1186/s42408-024-00253-3","url":null,"abstract":"Currently, no multiple century fire scar records have been constructed in the Lower Peninsula of Michigan, USA, a region where historical vegetation ranged from prairies and oak-dominated woodlands in the south to conifer-northern hardwood forests and swamps to the north. The western portion of the Huron-Manistee National Forests is located within this strong vegetation transition (i.e., “Tension Zone”) and, based on this study, has well-preserved remnant red pine trees dating back to at least the late 1400s with fire scars dating back to 1523. From fire scar records constructed at four study sites, we documented historical fires as having a wide range of fire intervals and seasonalities. A general timeline of fire activity changes in this region can be described as relatively frequent fire in the pre- and early-European contact eras, variable and generally less fire from this point forward until the period of major logging activities after which fire frequency was significantly increased. Historical fires were associated with drought in the year of fire. Some broad synchronies of fire occurrence existed among sites such as 3 of 4 sites recording fires in years 1717, 1774, and 1829. Interestingly, these years were not exceptionally dry nor among the driest fire years. Future development of fire scar records will likely improve spatio-temporal characterization of regional fire regimes including understanding of human-climate-fire dynamics.","PeriodicalId":12273,"journal":{"name":"Fire Ecology","volume":"298 1","pages":""},"PeriodicalIF":5.1,"publicationDate":"2024-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140070887","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}
Forest fires are a recurring issue in many parts of the world, including India. These fires can have various causes, including human activities (such as agricultural burning, campfires, or discarded cigarettes) and natural factors (such as lightning). The present study presents a comprehensive and advanced methodology for assessing wildfire susceptibility by integrating diverse environmental variables and leveraging cutting-edge machine learning techniques across Gujarat State, India. The primary goal of the study is to utilize Google Earth Engine to compare locations in Gujarat, India, before and after forest fires. High-resolution satellite data were used to assess the amount and types of changes caused by forest fires. The present study meticulously analyzes various environmental variables, i.e., slope orientation, elevation, normalized difference vegetation index (NDVI), drainage density, precipitation, and temperature to understand landscape characteristics and assess wildfire susceptibility. In addition, a sophisticated random forest regression model is used to predict land surface temperature based on a set of environmental parameters. The maps that result depict the geographical distribution of normalized burn ratio and difference normalized burn ratio and land surface temperature forecasts, providing valuable insights into spatial patterns and trends. The findings of this work show that an automated temporal analysis utilizing Google Earth Engine may be used successfully over a wide range of land cover types, providing critical data for future monitoring of such threats. The impact of forest fires can be severe, leading to the loss of biodiversity, damage to ecosystems, and threats to human settlements.
{"title":"Assessment of forest fire severity and land surface temperature using Google Earth Engine: a case study of Gujarat State, India","authors":"Keval H. Jodhani, Haard Patel, Utsav Soni, Rishabh Patel, Bhairavi Valodara, Nitesh Gupta, Anant Patel, Padam jee Omar","doi":"10.1186/s42408-024-00254-2","DOIUrl":"https://doi.org/10.1186/s42408-024-00254-2","url":null,"abstract":"Forest fires are a recurring issue in many parts of the world, including India. These fires can have various causes, including human activities (such as agricultural burning, campfires, or discarded cigarettes) and natural factors (such as lightning). The present study presents a comprehensive and advanced methodology for assessing wildfire susceptibility by integrating diverse environmental variables and leveraging cutting-edge machine learning techniques across Gujarat State, India. The primary goal of the study is to utilize Google Earth Engine to compare locations in Gujarat, India, before and after forest fires. High-resolution satellite data were used to assess the amount and types of changes caused by forest fires. The present study meticulously analyzes various environmental variables, i.e., slope orientation, elevation, normalized difference vegetation index (NDVI), drainage density, precipitation, and temperature to understand landscape characteristics and assess wildfire susceptibility. In addition, a sophisticated random forest regression model is used to predict land surface temperature based on a set of environmental parameters. The maps that result depict the geographical distribution of normalized burn ratio and difference normalized burn ratio and land surface temperature forecasts, providing valuable insights into spatial patterns and trends. The findings of this work show that an automated temporal analysis utilizing Google Earth Engine may be used successfully over a wide range of land cover types, providing critical data for future monitoring of such threats. The impact of forest fires can be severe, leading to the loss of biodiversity, damage to ecosystems, and threats to human settlements.","PeriodicalId":12273,"journal":{"name":"Fire Ecology","volume":"22 1","pages":""},"PeriodicalIF":5.1,"publicationDate":"2024-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140055747","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 : 2024-02-28DOI: 10.1186/s42408-024-00252-4
Martin C. Holdrege, Daniel R. Schlaepfer, Kyle A. Palmquist, Michele Crist, Kevin E. Doherty, William K. Lauenroth, Thomas E. Remington, Karin Riley, Karen C. Short, John C. Tull, Lief A. Wiechman, John B. Bradford
Wildfire is a major proximate cause of historical and ongoing losses of intact big sagebrush (Artemisia tridentata Nutt.) plant communities and declines in sagebrush obligate wildlife species. In recent decades, fire return intervals have shortened and area burned has increased in some areas, and habitat degradation is occurring where post-fire re-establishment of sagebrush is hindered by invasive annual grasses. In coming decades, the changing climate may accelerate these wildfire and invasive feedbacks, although projecting future wildfire dynamics requires a better understanding of long-term wildfire drivers across the big sagebrush region. Here, we integrated wildfire observations with climate and vegetation data to derive a statistical model for the entire big sagebrush region that represents how annual wildfire probability is influenced by climate and fine fuel characteristics. Wildfire frequency varied significantly across the sagebrush region, and our statistical model represented much of that variation. Biomass of annual and perennial grasses and forbs, which we used as proxies for fine fuels, influenced wildfire probability. Wildfire probability was highest in areas with high annual forb and grass biomass, which is consistent with the well-documented phenomenon of increased wildfire following annual grass invasion. The effects of annuals on wildfire probability were strongest in places with dry summers. Wildfire probability varied with the biomass of perennial grasses and forbs and was highest at intermediate biomass levels. Climate, which varies substantially across the sagebrush region, was also predictive of wildfire probability, and predictions were highest in areas with a low proportion of precipitation received in summer, intermediate precipitation, and high temperature. We developed a carefully validated model that contains relatively simple and biologically plausible relationships, with the goal of adequate performance under novel conditions so that useful projections of average annual wildfire probability can be made given general changes in conditions. Previous studies on the impacts of vegetation and climate on wildfire probability in sagebrush ecosystems have generally used more complex machine learning approaches and have usually been applicable to only portions of the sagebrush region. Therefore, our model complements existing work and forms an additional tool for understanding future wildfire and ecological dynamics across the sagebrush region.
{"title":"Wildfire probability estimated from recent climate and fine fuels across the big sagebrush region","authors":"Martin C. Holdrege, Daniel R. Schlaepfer, Kyle A. Palmquist, Michele Crist, Kevin E. Doherty, William K. Lauenroth, Thomas E. Remington, Karin Riley, Karen C. Short, John C. Tull, Lief A. Wiechman, John B. Bradford","doi":"10.1186/s42408-024-00252-4","DOIUrl":"https://doi.org/10.1186/s42408-024-00252-4","url":null,"abstract":"Wildfire is a major proximate cause of historical and ongoing losses of intact big sagebrush (Artemisia tridentata Nutt.) plant communities and declines in sagebrush obligate wildlife species. In recent decades, fire return intervals have shortened and area burned has increased in some areas, and habitat degradation is occurring where post-fire re-establishment of sagebrush is hindered by invasive annual grasses. In coming decades, the changing climate may accelerate these wildfire and invasive feedbacks, although projecting future wildfire dynamics requires a better understanding of long-term wildfire drivers across the big sagebrush region. Here, we integrated wildfire observations with climate and vegetation data to derive a statistical model for the entire big sagebrush region that represents how annual wildfire probability is influenced by climate and fine fuel characteristics. Wildfire frequency varied significantly across the sagebrush region, and our statistical model represented much of that variation. Biomass of annual and perennial grasses and forbs, which we used as proxies for fine fuels, influenced wildfire probability. Wildfire probability was highest in areas with high annual forb and grass biomass, which is consistent with the well-documented phenomenon of increased wildfire following annual grass invasion. The effects of annuals on wildfire probability were strongest in places with dry summers. Wildfire probability varied with the biomass of perennial grasses and forbs and was highest at intermediate biomass levels. Climate, which varies substantially across the sagebrush region, was also predictive of wildfire probability, and predictions were highest in areas with a low proportion of precipitation received in summer, intermediate precipitation, and high temperature. We developed a carefully validated model that contains relatively simple and biologically plausible relationships, with the goal of adequate performance under novel conditions so that useful projections of average annual wildfire probability can be made given general changes in conditions. Previous studies on the impacts of vegetation and climate on wildfire probability in sagebrush ecosystems have generally used more complex machine learning approaches and have usually been applicable to only portions of the sagebrush region. Therefore, our model complements existing work and forms an additional tool for understanding future wildfire and ecological dynamics across the sagebrush region. ","PeriodicalId":12273,"journal":{"name":"Fire Ecology","volume":"7 1","pages":""},"PeriodicalIF":5.1,"publicationDate":"2024-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140005070","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 : 2024-02-15DOI: 10.1186/s42408-024-00250-6
Octavio Toy-Opazo, Andrés Fuentes-Ramirez, Valeria Palma-Soto, Rafael A. Garcia, Kirk A. Moloney, Rodrigo Demarco, Andrés Fuentes-Castillo
Vegetation plays a crucial role in the ignition, propagation, and severity of fire, and understanding the relationship between plants and fire through flammability attributes has become a useful tool that is increasingly used in studies on fire dynamics worldwide. However, in the southern cone of South America, rather few studies have systematically and specifically addressed the flammability of vegetation, and yet fewer have compared native and non-native species. Given the increasing interest in knowing the flammability characteristics of vegetation, this review aims to assess the potential differences in flammability between native and non-native plant species that inhabit the southern cone and to identify the main methodologies and experiments used to analyze vegetation flammability. Twenty-eight species were identified, 18 native to the region and 10 non-native. Additionally, 64 experimental tests were revised to evaluate plant flammability. It was found that Cryptocarya alba, Acacia dealbata, Eucalyptus globulus, and Pinus ponderosa are the species with a high flammability index. By contrast, the species Araucaria araucana, Austrocedrus chilensis, Embothrium coccineum, and Persea lingue showed low flammability. The methodologies used to evaluate vegetation flammability were highly variable, with the use of epiradiators being the most frequent. Our review indicates that the geographic origin of vegetation (native vs. non-native in South America) is not a decisive factor in determining species-level differences in flammability. Other relevant factors that contribute with the degree of plant flammability include fuel moisture, the morphology of the species, and its internal chemical compounds. We highlight the necessity of continuing the study of plant flammability and advance in the standardization of protocols and measurements, using uniform criteria and increasing comparative studies between species, particularly in the southern cone of South America where catastrophic wildfires are increasing.
{"title":"Flammability features of native and non-native woody species from the southernmost ecosystems: a review","authors":"Octavio Toy-Opazo, Andrés Fuentes-Ramirez, Valeria Palma-Soto, Rafael A. Garcia, Kirk A. Moloney, Rodrigo Demarco, Andrés Fuentes-Castillo","doi":"10.1186/s42408-024-00250-6","DOIUrl":"https://doi.org/10.1186/s42408-024-00250-6","url":null,"abstract":"Vegetation plays a crucial role in the ignition, propagation, and severity of fire, and understanding the relationship between plants and fire through flammability attributes has become a useful tool that is increasingly used in studies on fire dynamics worldwide. However, in the southern cone of South America, rather few studies have systematically and specifically addressed the flammability of vegetation, and yet fewer have compared native and non-native species. Given the increasing interest in knowing the flammability characteristics of vegetation, this review aims to assess the potential differences in flammability between native and non-native plant species that inhabit the southern cone and to identify the main methodologies and experiments used to analyze vegetation flammability. Twenty-eight species were identified, 18 native to the region and 10 non-native. Additionally, 64 experimental tests were revised to evaluate plant flammability. It was found that Cryptocarya alba, Acacia dealbata, Eucalyptus globulus, and Pinus ponderosa are the species with a high flammability index. By contrast, the species Araucaria araucana, Austrocedrus chilensis, Embothrium coccineum, and Persea lingue showed low flammability. The methodologies used to evaluate vegetation flammability were highly variable, with the use of epiradiators being the most frequent. Our review indicates that the geographic origin of vegetation (native vs. non-native in South America) is not a decisive factor in determining species-level differences in flammability. Other relevant factors that contribute with the degree of plant flammability include fuel moisture, the morphology of the species, and its internal chemical compounds. We highlight the necessity of continuing the study of plant flammability and advance in the standardization of protocols and measurements, using uniform criteria and increasing comparative studies between species, particularly in the southern cone of South America where catastrophic wildfires are increasing.","PeriodicalId":12273,"journal":{"name":"Fire Ecology","volume":"29 1","pages":""},"PeriodicalIF":5.1,"publicationDate":"2024-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139764288","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 : 2024-02-13DOI: 10.1186/s42408-024-00251-5
Byron B. Lamont, Geoffrey E. Burrows, Juli G. Pausas
Our analyses of data in Luna et al. (Fire Ecology 19:52, 2023) do not support the proposal that dormancy release of the hard seeds in 12 species of Cistaceae is a “two-step process” involving high summer temperatures followed by fire-type heat. The reverse is true: subjection to a month of daily alternating temperatures of 50/20 °C (summer heat) is more likely to induce dormancy among initially soft seeds or secondary dormancy among those softened by fire heat or reduce the ability of fire heat to soften the seeds. The need to inspect seeds for the presence of an open “water gap” following various heat treatments, and using more realistic summer temperatures in future studies, is clear.
{"title":"Fire-type heat increases the germination of Cistaceae seeds in contrast to summer heat","authors":"Byron B. Lamont, Geoffrey E. Burrows, Juli G. Pausas","doi":"10.1186/s42408-024-00251-5","DOIUrl":"https://doi.org/10.1186/s42408-024-00251-5","url":null,"abstract":"Our analyses of data in Luna et al. (Fire Ecology 19:52, 2023) do not support the proposal that dormancy release of the hard seeds in 12 species of Cistaceae is a “two-step process” involving high summer temperatures followed by fire-type heat. The reverse is true: subjection to a month of daily alternating temperatures of 50/20 °C (summer heat) is more likely to induce dormancy among initially soft seeds or secondary dormancy among those softened by fire heat or reduce the ability of fire heat to soften the seeds. The need to inspect seeds for the presence of an open “water gap” following various heat treatments, and using more realistic summer temperatures in future studies, is clear.","PeriodicalId":12273,"journal":{"name":"Fire Ecology","volume":"32 1","pages":""},"PeriodicalIF":5.1,"publicationDate":"2024-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139764237","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}