E-Mail Alert

Add your e-mail address to receive forthcoming issues of this journal:

Journal Browser

Journal Browser

Special Issue "Wildland Fire, Forest Dynamics, and Their Interactions"

A special issue of Forests (ISSN 1999-4907). This special issue belongs to the section "Forest Ecology and Management".

Deadline for manuscript submissions: closed (15 February 2018)

Printed Edition Available!
A printed edition of this Special Issue is available here.

Special Issue Editors

Guest Editor
Dr. Marc-André Parisien

Natural Resources Canada, Canadian Forest Service, Northern Forestry Centre, 5320 122 Street, Edmonton, Alberta T6H 3S5, Canada
Website | E-Mail
Interests: Ecology of northern forests, Wildland fire risk, Ecological modeling, Conservation
Guest Editor
Dr. Enric Batllori

CREAF (Center for Ecological Research and Forestry Applications), Campus UAB - Edi-fici C, 08913 Bellaterra, Barcelona, Spain
Website | E-Mail
Interests: Cross-scale processes, Disturbance ecology, Ecosystem resilience, Environmental controls, Mediterranean ecosystems
Guest Editor
Dr. Carol Miller

United States Department of Agriculture Forest Service, Aldo Leopold Wilderness Research Institute, 790 East Beckwith Avenue, Missoula, Montana 59801, United States
Website | E-Mail
Interests: Restoring fire as an ecosystem process, Fire refugia, Fire risk analysis, Fire ecology
Guest Editor
Dr. Sean A. Parks

United States Department of Agriculture Forest Service, Aldo Leopold Wilderness Research Institute, 790 East Beckwith Avenue, Missoula, Montana 59801, United States
Website | E-Mail
Interests: Fire-on-fire interactions, Climate change, Disturbance ecology, Statistical fire modeling

Special Issue Information

Dear Colleagues,

Wildland fire is an important, pervasive, and a sometimes-destructive ecological process in many forest ecosystems across the globe. In some cases, wildland fire maintains and reinforces forest dynamics. This is common, for example, in forests with thick-barked species that are adapted to frequent, low-severity fires or in forests where species’ regenerative traits (e.g., serotiny, resprouting) allow them to endure regimes of recurrent high-severity fire. However, wildland fire can also act as a catalyst that changes the successional trajectory of forest ecosystems, particularly if the factors responsible for historical fire regimes (e.g., frequency, severity, or season) have been substantially altered and exceed species’ adaptive capacity. Examples of these situations include effects of extreme fire weather and drought, fuel buildup due to fire exclusion or insect-induced mortality, and interactions between these factors. Some of these situations may result in fire-induced conversions from forest to non-forest ecosystems.

We seek submissions aimed at wildland fire, forest dynamics, and their interactions. We are particularly interested in studies evaluating additional factors and stressors that influence the characteristics of fire, as well as the composition and structure of vegetation, such as insect- and drought-induced mortality, extreme weather events, human ignitions, excessive fuels, and climate change.

Dr. Marc-André Parisien
Dr. Enric Batllori
Dr. Carol Miller
Dr. Sean A. Parks
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All papers will be peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Forests is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 1800 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • Wildland fire
  • Forest dynamics
  • Interactions
  • Vegetation composition and structure
  • Fire behavior and effects
  • Non-fire disturbances
  • Successional trajectories
  • Fire-induced ecological change

Published Papers (18 papers)

View options order results:
result details:
Displaying articles 1-18
Export citation of selected articles as:

Research

Jump to: Review

Open AccessArticle Deforestation-Induced Fragmentation Increases Forest Fire Occurrence in Central Brazilian Amazonia
Forests 2018, 9(6), 305; https://doi.org/10.3390/f9060305
Received: 22 January 2018 / Revised: 25 April 2018 / Accepted: 1 May 2018 / Published: 1 June 2018
Cited by 1 | PDF Full-text (6023 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Amazonia is home to more than half of the world’s remaining tropical forests, playing a key role as reservoirs of carbon and biodiversity. However, whether at a slower or faster pace, continued deforestation causes forest fragmentation in this region. Thus, understanding the relationship [...] Read more.
Amazonia is home to more than half of the world’s remaining tropical forests, playing a key role as reservoirs of carbon and biodiversity. However, whether at a slower or faster pace, continued deforestation causes forest fragmentation in this region. Thus, understanding the relationship between forest fragmentation and fire incidence and intensity in this region is critical. Here, we use MODIS Active Fire Product (MCD14ML, Collection 6) as a proxy of forest fire incidence and intensity (measured as Fire Radiative Power—FRP), and the Brazilian official Land-use and Land-cover Map to understand the relationship among deforestation, fragmentation, and forest fire on a deforestation frontier in the Brazilian Amazonia. Our results showed that forest fire incidence and intensity vary with levels of habitat loss and forest fragmentation. About 95% of active fires and the most intense ones (FRP > 500 megawatts) were found in the first kilometre from the edges in forest areas. Changes made in 2012 in the Brazilian main law regulating the conservation of forests within private properties reduced the obligation to recover illegally deforested areas, thus allowing for the maintenance of fragmented areas in the Brazilian Amazonia. Our results reinforce the need to guarantee low levels of fragmentation in the Brazilian Amazonia in order to avoid the degradation of its forests by fire and the related carbon emissions. Full article
Figures

Graphical abstract

Open AccessArticle Spruce Budworm (Choristoneura fumiferana Clem.) Defoliation Promotes Vertical Fuel Continuity in Ontario’s Boreal Mixedwood Forest
Forests 2018, 9(5), 256; https://doi.org/10.3390/f9050256
Received: 15 February 2018 / Revised: 28 April 2018 / Accepted: 6 May 2018 / Published: 9 May 2018
PDF Full-text (2983 KB) | HTML Full-text | XML Full-text
Abstract
Spruce budworm, Choristoneura fumiferana (Clem.), defoliation has been shown to affect the occurrence of crown fire in Ontario, highlighting the need to better understand the driving factors of this effect on forest structure, including changes in fuel loading, type and position. Here, we [...] Read more.
Spruce budworm, Choristoneura fumiferana (Clem.), defoliation has been shown to affect the occurrence of crown fire in Ontario, highlighting the need to better understand the driving factors of this effect on forest structure, including changes in fuel loading, type and position. Here, we investigate five boreal mixedwood sites within four zones that experienced different durations of continuous defoliation by spruce budworm in northeastern Ontario. Duration of defoliation had significant effects on vertical stand components, namely, host overstory to host understory crown overlap, host overstory and host understory crown to downed woody debris overlap, and downed woody debris height and quantity. Vertical stand components tended to increase with the duration of continuous defoliation, with the highest vertical fuel continuity occurring after 16 years of continuous defoliation. Such increases in the vertical spatial continuity of fuels may be a key reason for the greater percentage of area burned in those forests which have recently sustained a spruce budworm outbreak. Full article
Figures

Figure 1

Open AccessFeature PaperArticle Composition and Structure of Forest Fire Refugia: What Are the Ecosystem Legacies across Burned Landscapes?
Forests 2018, 9(5), 243; https://doi.org/10.3390/f9050243
Received: 13 April 2018 / Revised: 27 April 2018 / Accepted: 27 April 2018 / Published: 2 May 2018
Cited by 3 | PDF Full-text (4713 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Locations within forest fires that remain unburned or burn at low severity—known as fire refugia—are important components of contemporary burn mosaics, but their composition and structure at regional scales are poorly understood. Focusing on recent, large wildfires across the US Pacific Northwest (Oregon [...] Read more.
Locations within forest fires that remain unburned or burn at low severity—known as fire refugia—are important components of contemporary burn mosaics, but their composition and structure at regional scales are poorly understood. Focusing on recent, large wildfires across the US Pacific Northwest (Oregon and Washington), our research objectives are to (1) classify fire refugia and burn severity based on relativized spectral change in Landsat time series; (2) quantify the pre-fire composition and structure of mapped fire refugia; (3) in forested areas, assess the relative abundance of fire refugia and other burn severity classes across forest composition and structure types. We analyzed a random sample of 99 recent fires in forest-dominated landscapes from 2004 to 2015 that collectively encompassed 612,629 ha. Across the region, fire refugia extent was substantial but variable from year to year, with an annual mean of 38% of fire extent and range of 15–60%. Overall, 85% of total fire extent was forested, with the other 15% being non-forest. In comparison, 31% of fire refugia extent was non-forest prior to the most recent fire, highlighting that mapped refugia do not necessarily contain tree-based ecosystem legacies. The most prevalent non-forest cover types in refugia were vegetated: shrub (40%), herbaceous (33%), and crops (18%). In forested areas, the relative abundance of fire refugia varied widely among pre-fire forest types (20–70%) and structural conditions (23–55%). Consistent with fire regime theory, fire refugia and high burn severity areas were inversely proportional. Our findings underscore that researchers, managers, and other stakeholders should interpret burn severity maps through the lens of pre-fire land cover, especially given the increasing importance of fire and fire refugia under global change. Full article
Figures

Figure 1

Open AccessArticle Exploring the Future of Fuel Loads in Tasmania, Australia: Shifts in Vegetation in Response to Changing Fire Weather, Productivity, and Fire Frequency
Forests 2018, 9(4), 210; https://doi.org/10.3390/f9040210
Received: 23 February 2018 / Revised: 7 April 2018 / Accepted: 9 April 2018 / Published: 16 April 2018
PDF Full-text (24295 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Changes to the frequency of fire due to management decisions and climate change have the potential to affect the flammability of vegetation, with long-term effects on the vegetation structure and composition. Frequent fire in some vegetation types can lead to transformational change beyond [...] Read more.
Changes to the frequency of fire due to management decisions and climate change have the potential to affect the flammability of vegetation, with long-term effects on the vegetation structure and composition. Frequent fire in some vegetation types can lead to transformational change beyond which the vegetation type is radically altered. Such feedbacks limit our ability to project fuel loads under future climatic conditions or to consider the ecological tradeoffs associated with management burns. We present a “pathway modelling” approach to consider multiple transitional pathways that may occur under different fire frequencies. The model combines spatial layers representing current and future fire danger, biomass, flammability, and sensitivity to fire to assess potential future fire activity. The layers are derived from a dynamically downscaled regional climate model, attributes from a regional vegetation map, and information about fuel characteristics. Fire frequency is demonstrated to be an important factor influencing flammability and availability to burn and therefore an important determinant of future fire activity. Regional shifts in vegetation type occur in response to frequent fire, as the rate of change differs across vegetation type. Fire-sensitive vegetation types move towards drier, more fire-adapted vegetation quickly, as they may be irreversibly impacted by even a single fire, and require very long recovery times. Understanding the interaction between climate change and fire is important to identify appropriate management regimes to sustain fire-sensitive communities and maintain the distribution of broad vegetation types across the landscape. Full article
Figures

Figure 1

Open AccessArticle Can Land Management Buffer Impacts of Climate Changes and Altered Fire Regimes on Ecosystems of the Southwestern United States?
Forests 2018, 9(4), 192; https://doi.org/10.3390/f9040192
Received: 15 February 2018 / Revised: 2 April 2018 / Accepted: 4 April 2018 / Published: 7 April 2018
Cited by 2 | PDF Full-text (48094 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Climate changes and associated shifts in ecosystems and fire regimes present enormous challenges for the management of landscapes in the Southwestern US. A central question is whether management strategies can maintain or promote desired ecological conditions under projected future climates. We modeled wildfire [...] Read more.
Climate changes and associated shifts in ecosystems and fire regimes present enormous challenges for the management of landscapes in the Southwestern US. A central question is whether management strategies can maintain or promote desired ecological conditions under projected future climates. We modeled wildfire and forest responses to climate changes and management activities using two ecosystem process models: FireBGCv2, simulated for the Jemez Mountains, New Mexico, and LANDIS-II, simulated for the Kaibab Plateau, Arizona. We modeled contemporary and two future climates—“Warm-Dry” (CCSM4 RCP 4.5) and “Hot-Arid” (HadGEM2ES RCP 8.5)—and four levels of management including fire suppression alone, a current treatment strategy, and two intensified treatment strategies. We found that Hot-Arid future climate resulted in a fundamental, persistent reorganization of ecosystems in both study areas, including biomass reduction, compositional shifts, and altered forest structure. Climate changes increased the potential for high-severity fire in the Jemez study area, but did not impact fire regime characteristics in the Kaibab. Intensified management treatments somewhat reduced wildfire frequency and severity; however, management strategies did not prevent the reorganization of forest ecosystems in either landscape. Our results suggest that novel approaches may be required to manage future forests for desired conditions. Full article
Figures

Graphical abstract

Open AccessArticle What Drives Low-Severity Fire in the Southwestern USA?
Forests 2018, 9(4), 165; https://doi.org/10.3390/f9040165
Received: 27 February 2018 / Revised: 20 March 2018 / Accepted: 21 March 2018 / Published: 24 March 2018
Cited by 1 | PDF Full-text (17351 KB) | HTML Full-text | XML Full-text
Abstract
Many dry conifer forests in the southwestern USA and elsewhere historically (prior to the late 1800’s) experienced fairly frequent surface fire at intervals ranging from roughly five to 30 years. Due to more than 100 years of successful fire exclusion, however, many of [...] Read more.
Many dry conifer forests in the southwestern USA and elsewhere historically (prior to the late 1800’s) experienced fairly frequent surface fire at intervals ranging from roughly five to 30 years. Due to more than 100 years of successful fire exclusion, however, many of these forests are now denser and more homogenous, and therefore they have a greater probability of experiencing stand-replacing fire compared to prior centuries. Consequently, there is keen interest in restoring such forests to conditions that are conducive to low-severity fire. Yet, there have been no regional assessments in the southwestern USA that have specifically evaluated those factors that promote low-severity fire. Here, we defined low-severity fire using satellite imagery and evaluated the influence of several variables that potentially drive such fire; these variables characterize live fuel, topography, climate (30-year normals), and inter-annual climate variation. We found that live fuel and climate variation (i.e., year-of-fire climate) were the main factors driving low-severity fire; fuel was ~2.4 times more influential than climate variation. Low-severity fire was more likely in settings with lower levels of fuel and in years that were wetter and cooler than average. Surprisingly, the influence of topography and climatic normals was negligible. Our findings elucidate those conditions conducive to low-severity fire and provide valuable information to land managers tasked with restoring forest structures and processes in the southwestern USA and other regions dominated by dry forest types. Full article
Figures

Figure 1

Open AccessArticle Temporal Patterns of Wildfire Activity in Areas of Contrasting Human Influence in the Canadian Boreal Forest
Forests 2018, 9(4), 159; https://doi.org/10.3390/f9040159
Received: 15 February 2018 / Revised: 15 March 2018 / Accepted: 19 March 2018 / Published: 21 March 2018
Cited by 2 | PDF Full-text (3621 KB) | HTML Full-text | XML Full-text
Abstract
The influence of humans on the boreal forest has altered the temporal and spatial patterns of wildfire activity through modification of the physical environment and through fire management for the protection of human and economic values. Wildfires are actively suppressed in areas with [...] Read more.
The influence of humans on the boreal forest has altered the temporal and spatial patterns of wildfire activity through modification of the physical environment and through fire management for the protection of human and economic values. Wildfires are actively suppressed in areas with higher human influence, but, paradoxically, these areas have more numerous ignitions than low-impact ones because of the high rates of human-ignited fires, especially during the springtime. The aim of this study is to evaluate how humans have altered the temporal patterns of wildfire activity in the Canadian boreal forest by comparing two adjacent areas of low and high human influence, respectively: Wood Buffalo National Park (WBNP) and the Lower Athabasca Plains (LAP). We carried out Singular Spectrum Analysis to identify trends and cycles in wildfires from 1970 to 2015 for the two areas and examined their association with climate conditions. We found human influence to be reflected in wildfire activity in multiple ways: (1) by dampening (i.e., for area burned)—and even reversing (i.e., for the number of fires)—the increasing trends of fire activity usually associated with drier and warmer conditions; (2) by shifting the peak of fire activity from the summer to the spring; (3) by altering the fire-climate association; and (4) by exhibiting more recurrent (<8 year periodicities) cyclical patterns of fire activity than WBNP (>9 years). Full article
Figures

Figure 1

Open AccessArticle Overstory Structure and Surface Cover Dynamics in the Decade Following the Hayman Fire, Colorado
Forests 2018, 9(3), 152; https://doi.org/10.3390/f9030152
Received: 16 February 2018 / Revised: 13 March 2018 / Accepted: 15 March 2018 / Published: 17 March 2018
Cited by 3 | PDF Full-text (3201 KB) | HTML Full-text | XML Full-text
Abstract
The 2002 Hayman Fire burned with mixed-severity across a 400-ha dry conifer study site in Colorado, USA, where overstory tree and surface cover attributes had been recently measured on 20 0.1-ha permanent plots. We remeasured these plots repeatedly during the first post-fire decade [...] Read more.
The 2002 Hayman Fire burned with mixed-severity across a 400-ha dry conifer study site in Colorado, USA, where overstory tree and surface cover attributes had been recently measured on 20 0.1-ha permanent plots. We remeasured these plots repeatedly during the first post-fire decade to examine how the attributes changed through time and whether changes were influenced by fire severity. We found that most attributes were temporally dynamic and that fire severity shaped their dynamics. For example, low-severity plots experienced a modest reduction in live overstory density due to both immediate and delayed tree mortality, and no change in live overstory basal area through time; in contrast, high-severity plots experienced an immediate and total loss of live overstory density and basal area. Large snag density in low-severity plots did not vary temporally because snag recruitment balanced snag loss; however, in high-severity plots large snag density increased markedly immediately post-fire and then declined by about half by post-fire year ten as snags fell. Mineral soil cover increased modestly immediately post-fire in low-severity plots and substantially immediately post-fire in high-severity plots, but changed little in ensuing years for either severity class. By incorporating pre-fire and repeatedly-measured post-fire data for a range of severities, our study uniquely contributes to the current understanding of wildfire effects in dry conifer forests and should be of interest to managers, researchers, and others. Full article
Figures

Figure 1

Open AccessArticle Topoedaphic and Forest Controls on Post-Fire Vegetation Assemblies Are Modified by Fire History and Burn Severity in the Northwestern Canadian Boreal Forest
Forests 2018, 9(3), 151; https://doi.org/10.3390/f9030151
Received: 15 February 2018 / Revised: 7 March 2018 / Accepted: 13 March 2018 / Published: 17 March 2018
Cited by 3 | PDF Full-text (4938 KB) | HTML Full-text | XML Full-text
Abstract
Wildfires, which constitute the most extensive natural disturbance of the boreal biome, produce a broad range of ecological impacts to vegetation and soils that may influence post-fire vegetation assemblies and seedling recruitment. We inventoried post-fire understory vascular plant communities and tree seedling recruitment [...] Read more.
Wildfires, which constitute the most extensive natural disturbance of the boreal biome, produce a broad range of ecological impacts to vegetation and soils that may influence post-fire vegetation assemblies and seedling recruitment. We inventoried post-fire understory vascular plant communities and tree seedling recruitment in the northwestern Canadian boreal forest and characterized the relative importance of fire effects and fire history, as well as non-fire drivers (i.e., the topoedaphic context and climate), to post-fire vegetation assemblies. Topoedaphic context, pre-fire forest structure and composition, and climate primarily controlled the understory plant communities and shifts in the ranked dominance of tree species (***8% and **13% of variance explained, respectively); however, fire and fire-affected soils were significant secondary drivers of post-fire vegetation. Wildfire had a significant indirect effect on understory vegetation communities through post-fire soil properties (**5%), and fire history and burn severity explained the dominance shifts of tree species (*7%). Fire-related variables were important explanatory variables in classification and regression tree models explaining the dominance shifts of four tree species (R2 = 0.43–0.65). The dominance of jack pine (Pinus banksiana Lamb.) and trembling aspen (Populus tremuloides Michx.) increased following fires, whereas that of black spruce (Picea mariana (Mill.) BSP.) and white spruce (Picea glauca (Moench) Voss) declined. The overriding importance of site and climate to post-fire vegetation assemblies may confer some resilience to disturbed forests; however, if projected increases in fire activity in the northwestern boreal forest are borne out, secondary pathways of burn severity, fire frequency, and fire effects on soils are likely to accelerate ongoing climate-driven shifts in species compositions. Full article
Figures

Figure 1

Open AccessArticle Ecoregional Patterns of Spruce Budworm—Wildfire Interactions in Central Canada’s Forests
Forests 2018, 9(3), 137; https://doi.org/10.3390/f9030137
Received: 15 February 2018 / Revised: 6 March 2018 / Accepted: 13 March 2018 / Published: 14 March 2018
Cited by 3 | PDF Full-text (3543 KB) | HTML Full-text | XML Full-text
Abstract
Wildfires and outbreaks of the spruce budworm, Choristoneura fumiferana (Clem.), are the two dominant natural disturbances in Canada’s boreal forest. While both disturbances have specific impacts on forest ecosystems, it is increasingly recognized that their interactions also have the potential for non-linear behavior [...] Read more.
Wildfires and outbreaks of the spruce budworm, Choristoneura fumiferana (Clem.), are the two dominant natural disturbances in Canada’s boreal forest. While both disturbances have specific impacts on forest ecosystems, it is increasingly recognized that their interactions also have the potential for non-linear behavior and long-lasting legacies on forest ecosystems’ structures and functions. Previously, we showed that, in central Canada, fires occurred with a disproportionately higher frequency during a ‘window of opportunity’ following spruce budworm defoliation. In this study, we use Ontario’s spatial databases for large fires and spruce budworm defoliation to locate where these two disturbances likely interacted. Classification tree and Random Forest procedures were then applied to find how spruce budworm defoliation history, climate, and forest conditions best predict the location of such budworm–fire interactions. Results indicate that such interactions likely occurred in areas geographically bound by hardwood content in the south, the prevalence of the three major spruce budworm host species (balsam fir, white spruce and black spruce) in the north, and climate moisture in the west. The occurrence of a spruce budworm–fire interaction inside these boundaries is related to the frequency of spruce budworm defoliation. These patterns provide a means of distinguishing regions where spruce budworm attacks are likely to increase fire risk. Full article
Figures

Figure 1

Open AccessArticle Predicting Potential Fire Severity Using Vegetation, Topography and Surface Moisture Availability in a Eurasian Boreal Forest Landscape
Forests 2018, 9(3), 130; https://doi.org/10.3390/f9030130
Received: 16 January 2018 / Revised: 6 March 2018 / Accepted: 6 March 2018 / Published: 8 March 2018
Cited by 7 | PDF Full-text (5604 KB) | HTML Full-text | XML Full-text
Abstract
Severity of wildfires is a critical component of the fire regime and plays an important role in determining forest ecosystem response to fire disturbance. Predicting spatial distribution of potential fire severity can be valuable in guiding fire and fuel management planning. Spatial controls [...] Read more.
Severity of wildfires is a critical component of the fire regime and plays an important role in determining forest ecosystem response to fire disturbance. Predicting spatial distribution of potential fire severity can be valuable in guiding fire and fuel management planning. Spatial controls on fire severity patterns have attracted growing interest, but few studies have attempted to predict potential fire severity in fire-prone Eurasian boreal forests. Furthermore, the influences of fire weather variation on spatial heterogeneity of fire severity remain poorly understood at fine scales. We assessed the relative importance and influence of pre-fire vegetation, topography, and surface moisture availability (SMA) on fire severity in 21 lightning-ignited fires occurring in two different fire years (3 fires in 2000, 18 fires in 2010) of the Great Xing’an Mountains with an ensemble modeling approach of boosted regression tree (BRT). SMA was derived from 8-day moderate resolution imaging spectroradiometer (MODIS) evapotranspiration products. We predicted the potential distribution of fire severity in two fire years and evaluated the prediction accuracies. BRT modeling revealed that vegetation, topography, and SMA explained more than 70% of variations in fire severity (mean 83.0% for 2000, mean 73.8% for 2010). Our analysis showed that evergreen coniferous forests were more likely to experience higher severity fires than the dominant deciduous larch forests of this region, and deciduous broadleaf forests and shrublands usually burned at a significantly lower fire severity. High-severity fires tended to occur in gentle and well-drained slopes at high altitudes, especially those with north-facing aspects. SMA exhibited notable and consistent negative association with severity. Predicted fire severity from our model exhibited strong agreement with the observed fire severity (mean r2 = 0.795 for 2000, 0.618 for 2010). Our results verified that spatial variation of fire severity within a burned patch is predictable at the landscape scale, and the prediction of potential fire severity could be improved by incorporating remotely sensed biophysical variables related to weather conditions. Full article
Figures

Graphical abstract

Open AccessArticle Pine Plantations and Invasion Alter Fuel Structure and Potential Fire Behavior in a Patagonian Forest-Steppe Ecotone
Forests 2018, 9(3), 117; https://doi.org/10.3390/f9030117
Received: 28 December 2017 / Revised: 28 February 2018 / Accepted: 28 February 2018 / Published: 3 March 2018
Cited by 3 | PDF Full-text (1845 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Planted and invading non-native plant species can alter fire regimes through changes in fuel loads and in the structure and continuity of fuels, potentially modifying the flammability of native plant communities. Such changes are not easily predicted and deserve system-specific studies. In several [...] Read more.
Planted and invading non-native plant species can alter fire regimes through changes in fuel loads and in the structure and continuity of fuels, potentially modifying the flammability of native plant communities. Such changes are not easily predicted and deserve system-specific studies. In several regions of the southern hemisphere, exotic pines have been extensively planted in native treeless areas for forestry purposes and have subsequently invaded the native environments. However, studies evaluating alterations in flammability caused by pines in Patagonia are scarce. In the forest-steppe ecotone of northwestern Patagonia, we evaluated fine fuels structure and simulated fire behavior in the native shrubby steppe, pine plantations, pine invasions, and mechanically removed invasions to establish the relative ecological vulnerability of these forestry and invasion scenarios to fire. We found that pine plantations and their subsequent invasion in the Patagonian shrubby steppe produced sharp changes in fine fuel amount and its vertical and horizontal continuity. These changes in fuel properties have the potential to affect fire behavior, increasing fire intensity by almost 30 times. Pruning of basal branches in plantations may substantially reduce fire hazard by lowering the probability of fire crowning, and mechanical removal of invasion seems effective in restoring original fuel structure in the native community. The current expansion of pine plantations and subsequent invasions acting synergistically with climate warming and increased human ignitions warrant a highly vulnerable landscape in the near future for northwestern Patagonia if no management actions are undertaken. Full article
Figures

Graphical abstract

Open AccessArticle Overlapping Bark Beetle Outbreaks, Salvage Logging and Wildfire Restructure a Lodgepole Pine Ecosystem
Forests 2018, 9(3), 101; https://doi.org/10.3390/f9030101
Received: 14 January 2018 / Revised: 21 February 2018 / Accepted: 24 February 2018 / Published: 27 February 2018
Cited by 3 | PDF Full-text (4771 KB) | HTML Full-text | XML Full-text
Abstract
The 2010 Church’s Park Fire burned beetle-killed lodgepole pine stands in Colorado, including recently salvage-logged areas, creating a fortuitous opportunity to compare the effects of salvage logging, wildfire and the combination of logging followed by wildfire. Here, we examine tree regeneration, surface fuels, [...] Read more.
The 2010 Church’s Park Fire burned beetle-killed lodgepole pine stands in Colorado, including recently salvage-logged areas, creating a fortuitous opportunity to compare the effects of salvage logging, wildfire and the combination of logging followed by wildfire. Here, we examine tree regeneration, surface fuels, understory plants, inorganic soil nitrogen and water infiltration in uncut and logged stands, outside and inside the fire perimeter. Subalpine fir recruitment was abundant in uncut, unburned, beetle-killed stands, whereas lodgepole pine recruitment was abundant in cut stands. Logging roughly doubled woody fuel cover and halved forb and shrub cover. Wildfire consumed all conifer seedlings in uncut and cut stands and did not stimulate new conifer regeneration within four years of the fire. Aspen regeneration, in contrast, was relatively unaffected by logging or burning, alone or combined. Wildfire also drastically reduced cover of soil organic horizons, fine woody fuels, graminoids and shrubs relative to unburned, uncut areas; moreover, the compound effect of logging and wildfire was generally similar to wildfire alone. This case study documents scarce conifer regeneration but ample aspen regeneration after a wildfire that occurred in the later stage of a severe beetle outbreak. Salvage logging had mixed effects on tree regeneration, understory plant and surface cover and soil nitrogen, but neither exacerbated nor ameliorated wildfire effects on those resources. Full article
Figures

Figure 1

Open AccessArticle Mixed-Severity Fire Fosters Heterogeneous Spatial Patterns of Conifer Regeneration in a Dry Conifer Forest
Forests 2018, 9(1), 45; https://doi.org/10.3390/f9010045
Received: 25 November 2017 / Revised: 11 January 2018 / Accepted: 17 January 2018 / Published: 20 January 2018
Cited by 4 | PDF Full-text (7472 KB) | HTML Full-text | XML Full-text
Abstract
We examined spatial patterns of post-fire regenerating conifers in a Colorado, USA, dry conifer forest 11–12 years following the reintroduction of mixed-severity fire. We mapped and measured all post-fire regenerating conifers, as well as all other post-fire regenerating trees and all residual (i.e., [...] Read more.
We examined spatial patterns of post-fire regenerating conifers in a Colorado, USA, dry conifer forest 11–12 years following the reintroduction of mixed-severity fire. We mapped and measured all post-fire regenerating conifers, as well as all other post-fire regenerating trees and all residual (i.e., surviving) trees, in three 4-ha plots following the 2002 Hayman Fire. Residual tree density ranged from 167 to 197 trees ha−1 (TPH), and these trees were clustered at distances up to 30 m. Post-fire regenerating conifers, which ranged in density from 241 to 1036 TPH, were also clustered at distances up to at least 30 m. Moreover, residual tree locations drove post-fire regenerating conifer locations, with the two showing a pattern of repulsion. Topography and post-fire sprouting tree species locations further drove post-fire conifer regeneration locations. These results provide a foundation for anticipating how the reintroduction of mixed-severity fire may affect long-term forest structure, and also yield insights into how historical mixed-severity fire may have regulated the spatially heterogeneous conditions commonly described for pre-settlement dry conifer forests of Colorado and elsewhere. Full article
Figures

Figure 1

Open AccessArticle Fire Effects on Historical Wildfire Refugia in Contemporary Wildfires
Forests 2017, 8(10), 400; https://doi.org/10.3390/f8100400
Received: 2 August 2017 / Revised: 6 October 2017 / Accepted: 10 October 2017 / Published: 20 October 2017
Cited by 12 | PDF Full-text (2663 KB) | HTML Full-text | XML Full-text
Abstract
Wildfire refugia are forest patches that are minimally-impacted by fire and provide critical habitats for fire-sensitive species and seed sources for post-fire forest regeneration. Wildfire refugia are relatively understudied, particularly concerning the impacts of subsequent fires on existing refugia. We opportunistically re-visited 122 [...] Read more.
Wildfire refugia are forest patches that are minimally-impacted by fire and provide critical habitats for fire-sensitive species and seed sources for post-fire forest regeneration. Wildfire refugia are relatively understudied, particularly concerning the impacts of subsequent fires on existing refugia. We opportunistically re-visited 122 sites classified in 1994 for a prior fire refugia study, which were burned by two wildfires in 2012 in the Cascade mountains of central Washington, USA. We evaluated the fire effects for historically persistent fire refugia and compared them to the surrounding non-refugial forest matrix. Of 122 total refugial (43 plots) and non-refugial (79 plots) sites sampled following the 2012 wildfires, one refugial and five non-refugial plots did not burn in 2012. Refugial sites burned more severely and experienced higher tree mortality than non-refugial plots, potentially due to the greater amount of time since the last fire, producing higher fuel accumulation. Although most sites maintained the pre-fire development stage, 19 percent of sites transitioned to Early development and 31 percent of sites converted from Closed to Open canopy. These structural transitions may contribute to forest restoration in fire-adapted forests where fire has been excluded for over a century, but this requires further analysis. Full article
Figures

Figure 1

Open AccessArticle Effects of Linear Disturbances and Fire Severity on Velvet Leaf Blueberry Abundance, Vigor, and Berry Production in Recently Burned Jack Pine Forests
Forests 2017, 8(10), 398; https://doi.org/10.3390/f8100398
Received: 29 September 2017 / Revised: 12 October 2017 / Accepted: 13 October 2017 / Published: 18 October 2017
Cited by 3 | PDF Full-text (2615 KB) | HTML Full-text | XML Full-text
Abstract
There is limited information on how velvet leaf blueberry (Vaccinium myrtilloides Michx.) responds to fires and existing small forest gaps associated with narrow linear disturbances. We measured the effects of narrow forest linear gaps from seismic lines used for oil and gas [...] Read more.
There is limited information on how velvet leaf blueberry (Vaccinium myrtilloides Michx.) responds to fires and existing small forest gaps associated with narrow linear disturbances. We measured the effects of narrow forest linear gaps from seismic lines used for oil and gas exploration versus adjacent (control) forests across a fire severity (% tree mortality) gradient on the presence, abundance (cover), vigor (height), and berry production of Vaccinium myrtilloides in recently (five-year) burned jack pine (Pinus banksiana Lamb.) forests near Fort McMurray, Alberta. Presence was greatest in forests that experienced low to moderately-high fire severities with declines at high fire severity. Abundance did not differ among seismic lines or adjacent forest, nor did it differ along a fire severity gradient. In contrast, vigor and berry production were greater on seismic lines compared to adjacent forests with fire severity positively affecting berry production, but not plant vigor. After controlling for changes in plant cover and vigor, berry production still increased with fire severity and within seismic lines compared with adjacent forests. Our findings suggest that narrow gaps from linear disturbances and fire severity interact to affect the fecundity (berry production) and growth (height) of Vaccinium myrtilloides. This has important implications for assessing the ecological effects of fire on linear disturbances associated with energy exploration in the western boreal forest. Full article
Figures

Figure 1

Open AccessArticle Environmental Influences on Forest Fire Regime in the Greater Hinggan Mountains, Northeast China
Forests 2017, 8(10), 372; https://doi.org/10.3390/f8100372
Received: 14 June 2017 / Revised: 23 September 2017 / Accepted: 26 September 2017 / Published: 30 September 2017
Cited by 2 | PDF Full-text (3156 KB) | HTML Full-text | XML Full-text
Abstract
Fires are the major disturbances in the Greater Hinggan Mountains, the only boreal forest in Northeast China. A comprehensive understanding of the fire regimes and influencing environmental parameters driving them from small to large fires is critical for effective forest fire prevention and [...] Read more.
Fires are the major disturbances in the Greater Hinggan Mountains, the only boreal forest in Northeast China. A comprehensive understanding of the fire regimes and influencing environmental parameters driving them from small to large fires is critical for effective forest fire prevention and management. Assisted with satellite imagery, topographic data, and climatic records in this region, this study examines its fire regimes in terms of ignition causes, frequencies, seasonality, and burned sizes in the period of 1980–2005. We found an upward trend for fire occurrences and burned areas and an elongated fire season over the three decades. The dates of the first fire in a year did not vary largely but those of the last fire were significantly delayed. Topographically, spring fires were prevalent throughout the entire region, while summer fires mainly occurred at higher elevations under severe drought conditions. Fall fires were mostly human-caused in areas at lower elevations with gentle terrains. An ordinal logistic regression revealed temperature and elevation were both significant factors to the fire size severity in spring and summer. Other than that, environmental impacts were different. Precipitation in the preceding year greatly influenced spring fires, while summer fires were significantly affected by wind speed, fuel moisture, and human accessibility. An important message from this study is that distinct seasonal variability and a significantly increasing number of summer and fall fires since the mid-1990s suggest a changing fire regime of the boreal forests in the study area. The observed and modeled results could provide insights on establishing a sustainable, localized forest fire prevention strategy in a seasonal manner. Full article
Figures

Figure 1

Review

Jump to: Research

Open AccessReview Revisiting Wildland Fire Fuel Quantification Methods: The Challenge of Understanding a Dynamic, Biotic Entity
Forests 2017, 8(9), 351; https://doi.org/10.3390/f8090351
Received: 24 August 2017 / Revised: 8 September 2017 / Accepted: 13 September 2017 / Published: 18 September 2017
Cited by 4 | PDF Full-text (742 KB) | HTML Full-text | XML Full-text
Abstract
Wildland fires are a function of properties of the fuels that sustain them. These fuels are themselves a function of vegetation, and share the complexity and dynamics of natural systems. Worldwide, the requirement for solutions to the threat of fire to human values [...] Read more.
Wildland fires are a function of properties of the fuels that sustain them. These fuels are themselves a function of vegetation, and share the complexity and dynamics of natural systems. Worldwide, the requirement for solutions to the threat of fire to human values has resulted in the development of systems for predicting fire behaviour. To date, regional differences in vegetation and independent fire model development has resulted a variety of approaches being used to describe, measure and map fuels. As a result, widely different systems have been adopted, resulting in incompatibilities that pose challenges to applying research findings and fire models outside their development domains. As combustion is a fundamental process, the same relationships between fuel and fire behaviour occur universally. Consequently, there is potential for developing novel fuel assessment methods that are more broadly applicable and allow fire research to be leveraged worldwide. Such a movement would require broad cooperation between researchers and would most likely necessitate a focus on universal properties of fuel. However, to truly understand fuel dynamics, the complex biotic nature of fuel would also need to remain a consideration—particularly when looking to understand the effects of altered fire regimes or changing climate. Full article
Forests EISSN 1999-4907 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top