Post-fire Salvage Research Articles

First Record of the Northern Spotted Owl Nesting in Forest Burned at the Highest Level of Severity

An instance of the Northern Spotted Owl (Strix occidentalis caurina) nesting successfully in severely burned forest indicates that under some circumstances, such habitat may indeed provide the species suitable habitat. Current forest-management approaches treat wildfire as the primary cause of habitat loss for both the Northern and California (S. o. occidentalis) Spotted Owls. Assumptions that severely burned forest does not provide any viable nesting or roosting habitat for these Spotted Owl subspecies has resulted in substantial post-fire logging and removal of burned trees throughout both owls’ ranges. In addition, forest management intended to prevent severe fires may entail thinning of unburned Spotted Owl habitat to reduce tree density and potential fuel loads. In the Mendocino National Forest of western Glenn County, California, I followed a pair of Northern Spotted Owls nesting and roosting deep within a large patch of severely burned forest two years after a fire, in a stand with no post-fire salvage logging, pre-fire thinning, fuels reduction, or attempts at restoration. A pair of Spotted Owls had used this location consistently since 1990, and the territory remained occupied with owls roosting and nesting successfully in 2022, despite 73% of the territory burning at high severity in 2020.

Occurrence records and taxonomic voucher specimens for study of wild bee communities in early seral forests generated by wildfire, post-fire salvage logging, and intensive forest management in southwest Oregon

Early seral forests regenerating after stand-replacing disturbance events can provide important habitat for populations of wild bees, an important group of pollinating insects. However, variability in the abundance and diversity of wild bee communities across different types of early seral forests is poorly understood, and can inform pollinator conservation efforts and sustainable forest management practices. In this study, we compared wild bee assemblages from early seral forests regenerating from three widespread stand-replacing disturbances across a gradient in stand ages in the Klamath Ecoregion of southwest Oregon using blue vane traps. Here, we present occurrence data for each bee specimen observed in the study, including voucher specimens deposited to the Oregon State Arthropod Collection.

Occurrence records and taxonomic voucher specimens for study of wild bee communities in early seral forests generated by wildfire, post-fire salvage logging, and intensive forest management in southwest Oregon

Early seral forests regenerating after stand-replacing disturbance events can provide important habitat for populations of wild bees, an important group of pollinating insects. However, variability in the abundance and diversity of wild bee communities across different types of early seral forests is poorly understood, and can inform pollinator conservation efforts and sustainable forest management practices. In this study, we compared wild bee assemblages from early seral forests regenerating from three widespread stand-replacing disturbances across a gradient in stand ages in the Klamath Ecoregion of southwest Oregon using blue vane traps. Here, we present occurrence data for each bee specimen observed in the study, including voucher specimens deposited to the Oregon State Arthropod Collection.

Long-term impact of an extreme wildfire and salvage logging legacies on ecosystem services provision: Decomposition and nutrient cycling in fire-prone Mediterranean pine forests

New wildfire regimes under accelerated global change may have unprecedented effects on ecosystem services (ES) provision but may also be mediated by the biological legacies left onsite. However, until now, we know very little about these effects, especially over the long term after fire. We investigated the impact of an extreme wildfire event and the burned wood legacies resulting from a decade post-fire salvage logging of dead trees on the recovery of two regulating/supporting ES, i.e., litter decomposition and nutrient cycling, in fire-prone Mediterranean ecosystems dominated by Pinus pinaster forests. For this, we (i) performed a two-year decomposition experiment using the Tea Bag Index (TBI) as a standard method to determine the percentage loss of litter mass and decomposition rates over time, and (ii) quantified soil biochemical variables (microbial biomass C, and β-glucosidase, urease and acid phosphatase enzymatic activities) reflecting nutrient cycling processes, in the burned area and in an adjacent 40-year unburned forest (hereafter, control). Furthermore, we analyzed the influence of soil chemical properties, vegetation variables, and fine (FWD) and coarse (CWD) woody debris characteristics on the recovery of the ES supply capacity. Although our results revealed initial differences with lower litter mass loss in the burned compared to the control area, possibly due to the higher humidity conditions created by mosses and FWD in the unburned forest that favour decomposition processes, decomposition rates in the burned area approached those in the control area at the end of the experiment. Furthermore, nutrient cycling driven by plant and microbial enzymatic activities, recovered fully a decade after fire. However, contrary to our expectations, burned wood legacies did not influence the recovery of ES provision, possibly because CWD remains were mostly intact and not decayed.

Do wildfires impact community structure and diversity of beetles (Coleoptera) in northern Mongolian forests? An investigation in Khentey Mountains

Forest fires are part of taiga ecosystem dynamics in northern Mongolia. We studied beetle diversity and community structure in 98 plots at five sites in different forest types (light taiga, mixed taiga, dark taiga, floodplain forest) and under different fire regimes. Each plot included five pitfall traps, one soil and litter sampling and recording of environmental variables. We used Hill numbers, GLMM and RDA to evaluate the data. In total, we collected 2692 individuals of 130 species and 72 genera of beetles, mainly Carabidae, Staphylinidae, Silphidae, and Leidodidae, with Pterostichus eximius occurring in 60% of all plots. Forest fires had a significant effect on diversity and community structure of Coleoptera at the local level. However, in all data, the effects of site and forest type outweighed the influence of fire. An RDA explained 32% of the variation in community patterns with the effects of fire and environmental parameters. RDA1 scores differed significantly by fire regime, suggesting different species composition of post-fire communities. Hylobius abietis, Byrrhus pilula and Leiodes sp2 were identified as indicator species for fire plots. Protection of beetle refugia is critical for successful habitat recolonization, but is threatened by the post-fire salvage logging practices common in Mongolian forestry.

Effects of salvage logging after forest fire on Siberian larch regeneration and ecosystem carbon stocks at the drought limit of the boreal forest in Mongolia

Post-fire salvage logging is widely applied in Mongolia's boreal forests with the intent to prevent intact forests from logging. The rationale behind this approach is the assumption that the additional disturbance caused by the removal of standing deadwood after stand-replacing fire is of no further significance for the already heavily disturbed ecosystem. However, while there is a global debate on effects of salvage logging for regeneration success, biodiversity, and soil health, little evidence has been collected from strongly drought-limited southern boreal forests of Central Asia. Comparing sites with and without salvage logging, we investigated forests of Siberian larch (Larix sibirica) ca. 20 years after stand-replacing fire and asked whether postfire salvage logging affected regeneration density, terminal shoot length and radial stem increment, ecosystem carbon stock densities, and reduced organic layer depth and compacted the soil. The biomass of the larch regeneration was significantly reduced by salvage logging, while tree growth was not affected. The ecosystem carbon stock density of burnt forest without salvage logging was 202 Mg C ha−1 and thus even in the lower range of intact larch forests from Mongolia, whereas burnt forests with salvage logging had organic carbon stock densities (104 Mg C ha−1) that were lower than those of unburned grasslands in the forest-steppe. These results show that removing deadwood from burnt forest is not insignificant, but has the potential to delay forest recovery and strongly reduces organic carbon storage. However, we did not find significant reductions in soil organic carbon stocks or soil compaction. Nonetheless, our findings raise the question of whether careful management of intact forests (especially by selective felling under a continuous-cover forestry regime) would be a more ecologically sustainable alternative than post-fire salvage logging.

Development of national post-fire restoration system to assess net GHG impacts and salvage biomass availability

In light of the recent unprecedented wildfires in Canada and the potential for increasing burned areas in the future, there is a need to explore post-fire salvage harvest and restoration and the implications for greenhouse gas (GHG) emissions. Salvage logging and replanting initiatives offer a potential solution by regrowing forests more quickly while meeting societal demands for wood and bioenergy.This study presents a comprehensive modeling framework to estimate post-fire salvage biomass and net GHG emissions relative to a ‘do-nothing’ baseline for all of Canada's harvest-eligible forests. Forest ecosystem carbon emissions and removals were modeled at 1-ha spatial resolution for Canadian forests using the Generic Carbon Budget Model (GCBM) from 1990 to 2070 using several forest inventory data sources with future harvest and wildfires.Building upon previous research, our work integrated the Canadian Forest Fire Danger Rating System fire intensity to estimate fire severity of future wildfires. For 2024 to 2070, we assessed the changes in ecosystem carbon, emissions from harvested wood products, and substitution benefits from avoided emissions-intensive materials, relative to a forward-looking baseline. Our prototype system provides a comprehensive framework, configuration files, links to datasets to quantify the net GHG of post-fire restoration, and sample results for validation.•Developed spatially explicit forest carbon modeling system for all of Canada's forests.•Assessed the net GHG reduction from post-fire restoration.•Used system approach to consider forests, wood products and substitution benefits.

Burn Severity and Postfire Salvage Logging Effects on Vegetation and Soil System in a Short-Term Period in Mediterranean Pine Forests

Wildfires are a natural part of the dynamics of Mediterranean forest ecosystems. The fire patterns in the Mediterranean basin have been altered mainly due to changes in land use and climate change. In 2017, a wildfire in Yeste (Spain) burned 3200 hectares of two Mediterranean pine forests. We investigated the effects of burn severity and postfire salvage logging practices on vegetation and soil properties in four experimental areas distributed within the wildfire perimeter. These areas included unburned, low, high, and high burn severity with salvage logging, all located under Pinus halepensis Mill and Pinus pinaster Aiton stands. Salvage logging was applied 18 months after the fire. We established 72 circular plots (nine per treatment and pine species). We collected soil samples to analyze physicochemical and biological soil properties, including pH, electrical conductivity (EC), soil organic matter (SOM) content, carbon from microbial biomass (CBM), basal soil respiration (BSR), metabolic quotient (qCO2), and two enzymatic activities: β-glucosidase (GLU) and phosphatase (PHP). To understand how vegetation changed after fire, we implemented three linear transects per plot to calculate α-diversity indices (richness, Shannon, and Simpson), vegetation coverage (COBV), fraction of bare soil (BSOIL), the number of postfire seedlings (NSeed) and their average height (Hm), and we grouped vegetation into different postfire adaptive strategies: facultative seeder (R+S+), obligate resprouter (R+S−), obligate seeder (R−S+), and non-fire-adapted (R−S−). We ran ANOVA and Tukey’s HSD post hoc tests to evaluate the differences between burn severity and salvage logging practices on the variables examined for each pine stand. We used PCA and correlation analysis to identify plant-soil interactions. Our results suggest that Pinus halepensis stands were more affected by the wildfire than Pinus pinaster stands due to the distinct characteristics of each species (morphology of the leaves, bark thickness, cone structure, etc.) and the significant differences observed in terms of pH, SOM, CBM, qCO2, GLU, PHP, and Nseed. The proportion of obligate resprouter species was higher in Pinus halepensis stands, and the obligate seeder species were higher in Pinus pinaster stands. The study highlighted the importance of monitoring burn severity and postfire management practices to promote forest recovery and reduce wildfire risk. Limiting the negative impact of postfire salvage logging practices can enhance the resilience of vulnerable ecosystems.

Assessing spatial patterns of burn severity for guiding post-fire salvage logging in boreal forests of Eastern Canada

Areas affected by forest fires are increasing worldwide, making salvage logging (i.e., harvesting fire-affected trees) an increasingly used practice to reduce the economic impacts of fire on forestry. However, salvage logging can have strong ecological impacts, notably on post-fire forest regeneration and biodiversity. Burn severity (i.e., the degree to which fires impact the vegetation and soil) is also a central element that interacts with pre-fire forest characteristics and salvages logging to control post-fire forest dynamics and biodiversity. In an ecosystem-based forest management context, spatial patterns of burn severity should thus be considered when planning salvage logging operations. This study presents a simple and innovative method to generate burn severity maps with Landsat and Sentinel-2 multispectral imageries to support salvage logging operations rapidly after a fire event. We assembled a unique dataset involving 330 plots from 10 burns (from 2010 to 2020) in which burn severity has been estimated on the field using the composite burn index (CBI) approach in eastern North America. CBI values were modelled as a univariate function of changes in spectral indices using the first cloud-free post-fire satellite images taken after the burns. Our results demonstrate that using free satellite images with straightforward methods can produce reliable and ecologically meaningful burn severity maps within the few weeks following a fire event. The method was then applied to a case study with salvage logging that illustrates how our burn severity maps could be a useful tool for guiding post-fire forestry operations in an ecosystem-based management context. We combined burn severity maps with pre-fire forest composition and age maps to assess immediate post-fire forest. We discuss how such an approach helps to guide salvage planning and maintain residual forests that are representative of the initial post-fire spatial variability in burn severity and pre-fire vegetation. We conclude that rapid mapping of burn severity after a forest fire event may offer many other applications for identifying and managing recently burned forests.

Effects of burn severity and postfire salvage logging on carnivore communities in montane forests

Abstract Wildfire and postfire salvage logging are major drivers of forest succession in western North America. Although postfire landscapes support a variety of carnivore species, it is unclear how these animals respond to differing patterns and severities of burning, or to additional landscape change from postfire salvage logging. Open, early-seral habitats created by these disturbances are predicted to benefit generalists such as coyotes (Canis latrans) and weasels (Mustela spp.), but restrict the activity of forest specialists such as Canadaian Lynx (Lynx canadensis) and Pacific Marten (Martes caurina). We used winter track surveys, supplemented with remote cameras, to examine carnivore habitat use in and around large, mixed-severity burns in north-central Washington, United States (burned in 2006), and central British Columbia, Canada (burned in 2010, then partially salvage-logged; some areas reburned in 2017). At 10 to 13 years postfire, marten had similar detection rates across lightly and severely burned areas of the 2006 burn, as did coyotes. Marten selected lightly burned areas of the 2010 burn (6 to 9 years postfire) over higher burn severities, and selected burns over adjacent unburned forests. Weasels selected areas of higher burn severity on both landscapes, while Lynx selected lower burn severities. Weasels and coyotes selected areas with a greater proportion of salvage-logged habitat in the 2010 burn, while marten, lynx, and wolves (Canis lupus) avoided areas with salvage logging. Fishers (Pekania pennanti) showed no clear patterns of selection or avoidance in relation to burn severity or salvage logging. Burn severity strongly influences wildlife activity postfire; lightly burned residual habitats are critical for forest specialists. Postfire salvage logging alters carnivore communities and may hinder species that require structurally complex landscapes.

Informing Sustainable Forest Management: Remote Sensing Strategies for Assessing Soil Disturbance after Wildfire and Salvage Logging

Wildfires have nearly become a guaranteed annual event in most western National Forests. Severe fire effects can be mitigated with a goal of minimizing the hydrologic response and promoting soil and vegetation recovery towards the pre-disturbance condition. Sometimes, post-fire actions include salvage logging to recover timber value and to remove excess fuels. Salvage logging was conducted after three large wildfires on the Lolo National Forest in Montana, USA, between 2017 and 2019. We evaluated detrimental soil disturbance (DSD) on seven units that were burned at low, moderate, and high soil burn severity in 2022, three to five years after the logging occurred. We found a range of exposed soil of 5%–25% and DSD from 3% to 20%, and these values were significantly correlated at r = 0.88. Very-high-resolution WorldView-2 imagery that coincided with the field campaign was used to calculate Normal Differenced Vegetation Index (NDVI) across the salvaged areas; we found that NDVI values were significantly correlated to DSD at r = 0.87. We were able to further examine this relationship and determined NDVI threshold values that corresponded to high-DSD areas, as well as develop a model to estimate the contributions of equipment type, seasonality, topography, and burn severity to DSD. A decision-making tool which combines these factors and NDVI is presented to support land managers in planning, evaluating, and monitoring disturbance from post-fire salvage logging.

Modeling post-fire regeneration patterns under different restoration scenarios to improve forest recovery in degraded ecosystems

BackgroundChanges in disturbance regimes triggered by land use and climate change can significantly alter forest ecosystems by modifying the distribution of some species and hindering post-disturbance tree regeneration dynamics. Applied nucleation (AN) could be a valuable active restoration approach for promoting natural recovery in forest ecosystems affected by stand-replacing disturbances as it improves seed availability and microsite conditions. ObjectivesThe study aimed to investigate the potential of AN under different scenarios in a mountain forest ecosystem of the Northwestern Italian Alps dominated by Scots pine (Pinus sylvestris L.). The area was affected by a large stand-replacing fire in 2005 and post-fire salvage logging that amplified ecosystem degradation and dampened natural tree regeneration. MethodsWe assessed the main drivers guiding natural post-fire natural recovery and identified suitable sites for tree regeneration through a machine learning correlative model (Bayesian Additive Regression Tree, BART). Specifically, we used several environmental predictors (e.g., topography, wind direction, and distance from seed trees) to model the occurrence of natural tree regeneration. We predicted the probability of tree regeneration presence at landscape scale under the current situation (fire followed by salvage logging) and a set of AN scenarios characterized by an increase in nuclei density, since distance from seed trees emerged as the most important driver for natural tree regeneration. Starting from the situation 16 years after the fire, we reclassified the prediction raster into a binary map of intervention priority (priority and non-priority patches), using the probability value that maximized the model accuracy (true skill statistic; TSS) as threshold. Patches with scarce pine regeneration were considered as high intervention priority sites for AN. These predictions made it possible to assess the most efficient active management scenario in terms of promoting forest recovery. ConclusionsThe simulations showed the positive effects of AN on natural tree regeneration and the importance of site selection for plantations, proving that AN could be a promising post-fire management technique that can minimize human interventions and their associated economic and ecological costs. To our knowledge, this work is the first AN simulation in a temperate mountain ecosystem. The selection of favorable sites can be further improved by considering fine-scale characteristics through field experiments and cross-scale integration.

Examining the temporal effects of wildfires on forest birds: Should I stay or should I go?

In flammable ecosystems, forest dynamics are affected by fire suppression, climate change and changes in land use that cause the frequency and intensity of fires to diverge from natural fire regimes. Although afforestation provides new habitats for forest species, fire can reverse its benefits by penalizing forest species. Shorter fire recurrence may also affect the capacity of original habitats to recover with post-fire salvage logging adding to the picture and having both direct and indirect effects on birds. To identify the underlying factors driving temporal variations in forest bird populations after wildfires, we performed counts in 685 transects located in 68 burnt areas in Catalonia (NE Iberian Peninsula), ranging from one to 11 years post-fire. Among the 20 studied forest species, 18 related significantly to time since fire and 14 to water deficit. Post-fire bird responses mainly fitted to non-lineal responses, such as irruptive and inverse-irruptive trends; whereas water deficit matched with the inclined and bell-shaped trends. Individual site fidelity seems behind the decision of forest birds to stay or leave after a fire, leading to increase frequency of occurrence immediately after fire but this effect tends to diminish over time. In terms of the spatial characteristics of burnt areas, the majority of species showed a positive relationship with fire severity heterogeneity and the density of unburnt patches. On the other hand, salvage logging negatively affected forest bird diversity. Bird diversity also decreased with the time since fire and in the driest transects but fire heterogeneity was positive for alpha and beta bird forest diversity. The relationships between forest birds and the mosaic of burnt and unburnt areas created by wildfires plays a critical role in maintaining biodiversity in fire-prone ecosystems. Thus, limiting post-fire disturbance (e.g. salvage logging) and promoting natural regeneration could be an effective strategy that will benefit forest organisms such as birds. Maintaining unburnt patches and creating a mosaic of burn severity and vegetation will promote habitat heterogeneity and benefit a diverse range of bird species.

Fire-killed forest biomass for mills and communities and bioenergy GHG impacts

We examine the supply chains of post-fire salvage harvest to 28 mills or 10 communities in British Columbia, Canada, and assess the net change in GHG emissions for community bioenergy and biofuels, relative to a ‘do-nothing’ baseline with fossil fuel use.Lowest-cost supply chains for post-fire salvage had largest hauled biomass for mills in the southern interior of the province, with mills in close proximity to each other having small fibresheds and low haul costs. Supply chains were also quantified for salvage biomass hauled to communities by using a lowest GHG optimization routine that selected between liquid transportation fuels or community bioenergy (heat and/or electricity). For the first few decades, avoided GHG emissions were larger when biomass was used for bioenergy (heat and/or electricity), mainly in larger communities, to avoid fossil fuel burning. As energy systems decarbonized, biomass was used for biofuels, and production was more evenly distributed amongst the communities.Adding these results to an integrated framework with previously published ecosystem emissions and removals assessed the net change in GHG emissions for a post-fire rehabilitation and bioenergy scenario relative to a ‘do-nothing’ baseline with continued fossil fuel use. We found that there was an initial increase in net GHG emissions even though biogenic emissions from bioenergy were partially offset by avoided fossil fuel emissions. Over time, an enhanced sink from rehabilitation activities combined with avoided fossil fuel emissions resulted in a cumulative (2020–2070) GHG reduction at median levels of −6 TgCO2e with a range from reduced emissions of −39 TgCO2e to increased emissions 37 TgCO2e. Cumulative avoided fossil emissions were −62 TgCO2e with a range from −49 TgCO2e to −86 TgCO2e.

Differentiating effects of salvage logging and recovery patterns on post-fire boreal forests in Northeast China using a modified forest disturbance index

ABSTRACT Forests are resilient to a range of disturbances, but combinations of severe natural and anthropogenic disturbances (e.g. wildfire and logging) may inhibit forest recovery and lead to forest degradation. Recent studies have explored long-term forest-disturbance detection and forest-recovery dynamics by using free and open-access remote-sensing images. However, mapping consecutive multiple disturbance agents is challenging using existing automated change-detection algorithms because the reduced canopy reflectance and the smoothing of consecutive disturbance signals mean that the initial disturbance cannot be spectrally separated from the second disturbance. Furthermore, uncertainty remains about post-disturbance vegetation dynamics and the effects of forest recovery under the interaction of burn severity, biological-legacy management, and active forest restoration (i.e. artificial regeneration and assisted natural regeneration). This contributes to biases in long-term forest-recovery monitoring, which are not conducive to the guidance of post-fire vegetation recovery. Here, we propose a modified disturbance index to separate the spectral characteristics of fire and forest logging using normalized tasseled-cap components (brightness and wetness) and detect the spatiotemporal distribution of post-fire logging by means of an index threshold and image differencing. On this basis, the recovery patterns of the post-fire forest are differentiated by considering the cumulative effect of fire, post-fire logging, and recovery approaches. The method is tested in the burn areas of the 5.6 Fire in the Greater Hinggan Mountain area (the largest forest fire in recorded history in China), giving an overall accuracy of 85% in post-fire forest logging mapping. Our results confirm that biological legacies (i.e. trees, logs, and snags) were removed across many areas in the fire, with activities peaking in the second year after the fire and located chiefly in areas of moderate and high burn severity. By identifying post-fire logging, the fluctuation and high disturbance index of the conventional temporal trajectory in the early stage of forest recovery are explained. The large-scale salvage logging slowed the recovery of the post-fire forest ecosystem and influenced the recovery process through the interaction of burn severity and active forest restoration. In areas of high burn severity, assisted natural regeneration (i.e. natural regeneration with artificial aids such as clearing the snags, weeding, digging pits, and supplemental planting) preserved biological legacies and achieved a higher proportion of forest recovery, second only to non-logged areas where natural regeneration (i.e. forestry recovering naturally without any artificial intervention) occurred. By contrast, salvage logging followed by artificial regeneration (i.e. clear-cutting all dead or damaged trees followed by tree planting or artificial seeding) hindered vegetation recovery in the early stage, but it improved the recovery rate in years 10–20 and approached the recovery proportion of non-logged areas where natural regeneration occurred as the recovery progressed and habitat conditions improved. The proposed method is shown to offer important advantages in detecting post-fire salvage logging, and it provides improved guidance for forest managers in developing strategies for forest recovery.

Effects of wildfire and post-fire salvage logging on rainsplash erosion in a semi-arid pine forest of Central Eastern Spain

Rainsplash erosion on forested hillslopes can be increased by both wildfires and post-fire salvage logging, especially under semi-arid Mediterranean conditions. However, few studies have compared rainsplash erosion among forest sites impacted by logging to other forest areas. To fill this gap, this study has evaluated surface runoff and soil erosion in a burnt and logged (manually or mechanically) pine forest of Central-Eastern Spain under simulated rainfall and compared it to unlogged and unburnt plots. Compared to the unburnt plots, surface runoff significantly increased (over 150%) in logged areas, with a peak of 220% on the areas directly subjected to logging machinery. Peak runoff was substantially increased by fire (+130%) and less by logging (+8. Soil loss due to rainsplash erosion was about 235% (manual logging) to 750% (mechanical logging) higher compared to the unburnt plots. Wildfire exerted a much higher soil disturbance compared to salvage logging, with a soil hydrological response that can be up to an order of magnitude higher. The increased runoff and erosion rates in response to wildfire and logging were ascribed to soil compaction, which increased on average 60% on logged plots as well as to the removal of vegetation cover (−80%), whereas soil roughness played a minor role. From these results, we suggest using lightweight machinery in burnt soils, to reduce surface runoff and erosion. The possibility of building contour felled log debris using the burnt wood may also be considered, in order to retain the eroded sediments.

Ecosystemic resilience of a temperate post-fire forest under extreme weather conditions

IntroductionThe effects of climate change are exacerbating the fire risk in forests worldwide. Conifer plantations in particular are especially vulnerable to fire outbreaks. At the end of the extraordinarily hot and dry summer of 2018, a forest pine plantation burned in Brandenburg, NE Germany. Different forestry interventions were carried out after the fire, while one area of the damaged plantation remained untouched.MethodsWe investigated the resilience of the forest ecosystem and the effectiveness of different active and passive forest restoration measures during the subsequent relatively warm and dry years 2019–2021.ResultsOne year after the fire, Populus tremula showed strong spontaneous colonization at all sites. In contrast, the majority of planted Pinus sylvestris plantlets died on the plots that had been salvage-logged after the fire. Three years after the fire, Populus tremula successfully established itself as the dominant tree species on all plots, with the highest abundance on the plot where the overstorey of the dead pines was left. Betula pendula, Salix caprea, and Pinus sylvestris showed lower abundance, with their proportion increasing with decreasing cover by dead trees. The distribution of regrowing trees is very heterogeneous across the different treatments and plots. In the clear-cut plots, the extreme microclimatic conditions expose the young trees to additional heat and drought, while the retention of deadwood measurably buffers the temperature and water stress.DiscussionThe resilience and adaptability of naturally regenerating forests that develop into ecosystems that are more diverse seem more promising than restoration through intervention. Apart from hampering restoration under extreme weather conditions, post-fire salvage logging contributes to soil degradation and loss of organic carbon.

Temporal differences in snail diversity responses to wildfires and salvage logging

SummarySpecies tend to peak in abundance at different times after fires. Over time, species richness (α) and landscape heterogeneity are prone to increase and lead to greater between-site diversity (β). However, post-fire salvage logging can reduce β-diversity, both directly and through its influence on succession. The as-yet understudied response of land snails to long-term habitat modification after wildfires and forest management is important for decision-making in forest restoration and conservation. We expected to detect differences in land snails and diversity in both the short and long term and between treatments in a natural park in the Mediterranean Basin. However, our results showed that post-fire management was a non-significant variable for snail community diversity, the exception being open-habitat endemic species. Plant succession and leaf litter cover were the main variables that shaped snail diversity and abundance over time after fires. Eighteen years after a fire, the land snail diversity had improved and the community composition had diversified, irrespective of the post-fire treatment, but threatened species disappeared and the total snail numbers had notably declined. To preserve threatened open-habitat species, prescribed fires and livestock grazing are recommended in combination with mature areas that can act as shelters where forest snails can recover from future disturbances.

Long-term response of open-habitats species to wildfire salvage logging: the endangered European wild rabbit as example

Salvage logging treatments, a type of logging to economic returns after natural disturbance, are often applied in the aftermath of wildfires. Specialist or dependent species of open-habitat usually increase their populations in the short-term after wildfires and post-fire salvage logging. However, the long-term effects on threatened open-habitat species such as the European wild rabbit (Oryctolagus cuniculus L.) are still poorly known. Thus, plant productivity, habitat heterogeneity and rabbit abundance were studied in the north-east Iberian Peninsula in four type of post-fire treatment plots: (1) unburnt, (2) salvage logging with branches left on the ground, (3) salvage logging and manual removal of branches, and (4) recurrent fires. Both the time since the fire and the treatment affected plant productivity and habitat heterogeneity. Plant productivity was quicker in treatments when branches were left on the ground or when branches were removed than in recurrent fire plots. Rabbit relative abundance increased in the short term but dramatically declined over time after fires, especially in the plots where branches were left on the ground and with recurrent fires, in which rabbit abundances fell dramatically. In the long-term, the lack of food availability and adequate habitat structure are the main factors affecting the maintenance of the rabbit population. An appropriate moment for managing burnt areas to favour the persistence of rabbit is between the fifth and sixth year after the fire. These actions also benefit the reduction of environmental biomass and so help prevent future severe wildfires.

Short-term effects of post-fire salvage logging intensity and activity on breeding birds in the Sierra Nevada Mountains, USA

BackgroundSalvage logging of fire-killed trees in western US conifer forests has been shown to negatively affect many wildlife species, but there are few quantitative studies from the Sierra Nevada, CA. Salvage intensity (i.e., the proportion of fire-killed trees removed during logging activities) has also rarely been measured; instead, most studies track the presence/absence of salvage activities. We explored the effects of post-fire salvage on the breeding bird community following the 2012 Chips and 2013 Rim fires using a before-after control-impact sample design, and modeled species responses to salvage including a test of whether species responded to salvage intensity or the presence of salvage activities as a whole.ResultsSalvage operations removed an average of 71% of the snag basal area in the Chips Fire and 64% in the Rim Fire within 50 m of our salvaged survey locations. Bird species responses to salvage in both fires were largely non-significant or negative (Chips: 11 negative, 4 positive, 19 non-significant; Rim: 13 negative, 4 positive, 20 non-significant). Statistical support for the salvage intensity vs. salvage activity models was split evenly among all species. Positive salvage responders in both fires included species adapted to open habitats and seed consumers, while a wide variety of species, including woodpeckers, species associated with open and dense mature forest, and some shrub nesters, responded negatively to salvage. We also evaluated five salvage prescription scenarios based on snag basal area, salvage intensity, and area treated to determine whether any combination could minimize the negative effects on the salvage-sensitive species yet retain the same salvage yield. The scenarios with the smallest area targeted with high-intensity salvage saw the smallest declines in abundance and diversity, but nearly all scenarios reduced both measures.ConclusionsNo combinations of salvage intensity and distribution from among the scenarios we explored were able to fully mitigate the negative effect on the bird community; however, the magnitude of declines in abundance and diversity was smaller than expected, and the majority of the species analyzed had a non-significant response. We recommend targeting salvage activities in the Sierra Nevada to those locations where snags pose a safety issue or where reforestation is most needed to conserve this fire-adapted bird community.