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The article discusses the 2022 North American Forest Ecology Workshop (NAFEW) with the theme "Turning Ecological Answers into Forest Management Actions," highlighting the importance of forest science in sustainable forest management practices and how the research community contributes to evidence-based policies.

Forest understory vegetation is an important characteristic of the forest. Predicting and mapping understory is a critical need for forest management and conservation planning, but it has proved difficult with available methods to date. LiDAR has the potential to generate remotely sensed forest understory structure data, but this potential has yet to be fully validated. Our objective was to examine the capacity of LiDAR point cloud data to predict forest understory cover. We modeled ground-based observations of understory structure in three vertical strata (0.5 m to < 1.5 m, 1.5 m to < 2.5 m, 2.5 m to < 3.5 m) as a function of a variety of LiDAR metrics using both mixed-effects and Random Forest models. We compared four understory LiDAR metrics designed to control for the spatial heterogeneity of sampling density. The four metrics were highly correlated and they all produced high values of variance explained in mixed-effects models. The top-ranked model used a voxel-based understory metric along with vertical stratum (Akaike weight = 1, explained variance = 87%, cross-validation error = 15.6%). We found evidence of occlusion of LiDAR pulses in the lowest stratum but no evidence that the occlusion influenced the predictability of understory structure. The Random Forest model results were consistent with those of the mixed-effects models, in that all four understory LiDAR metrics were identified as important, along with vertical stratum. The Random Forest model explained 74.4% of the variance, but had a lower cross-validation error of 12.9%. We conclude that the best approach to predict understory structure is using the mixed-effects model with the voxel-based understory LiDAR metric along with vertical stratum, because it yielded the highest explained variance with the fewest number of variables. However, results show that other understory LiDAR metrics (fractional cover, normalized cover and leaf area density) would still be effective in mixed-effects and Random Forest modelling approaches. [ABSTRACT FROM AUTHOR]

Abstract Land-use intensification can lead to taxonomic and/or functional homogenization of biotic communities, with potential consequences for ecosystem functioning. In boreal forests, managers are increasingly considering intensifying woody biomass removal for bioenergy, but associated functional effects on soil fauna that use microhabitats associated with this biomass remain poorly understood. Two years after harvesting, we assessed the effects of an increasing intensity gradient of biomass removal in a northeastern Ontario jack pine (Pinus banksiana) stand on the functional structure of Collembola and Oribatida communities, two abundant soil taxa. The gradient ranged from (1) uncut forest to (2) stem-only harvesting to intense biomass removal through (3) whole-tree harvesting (stem, top and branches) with (4) stump removal and (5) additional removal of organic soil strata. Morphological and life-history response traits associated with hypothesized functions were measured to determine changes in the functional structure (species trait diversity and composition) of communities in response to the gradient and related environmental changes. We found that functional structure of communities of both taxa was overall significantly modified by biomass removal through a compositional shift in species traits in comparison to uncut forest. Functional homogenization was observed for Oribatida communities with a loss of species that were surface-dwelling, larger, predominantly sexually reproducing and mostly micro-detritivorous. In contrast, Collembola communities were less affected with only the most extreme treatment showing a more homogenized community than the uncut forest. These functional changes were mainly explained by fewer suitable microhabitats, characterized for example by a more stable microclimate as well as more abundant and diverse food resources, due to the disturbance of forest floor organic cover with harvesting. To improve sustainable management of boreal forests, long-term studies will be needed to assess if partial functional homogenization of soil mesofauna by intensive practices persists through time and may influence soil ecosystem function. Highlights • Biomass removal reduced diversity and altered trait composition of soil mesofauna. • Fewer epedaphic, sexually reproducing and micro-detritivorous Oribatida species. • Collembola were less sensitive vs. Oribatida likely due to their different ecology. • Changes were mostly related to altered soil organic cover and microclimate. [ABSTRACT FROM AUTHOR]

Information about post-disturbance regeneration success and successional dynamics is critical to predict forest ecosystem resistance and resilience to disturbances and climate change. Our objective was to identify and classify post-disturbance empirical research conducted by the Canadian Forest Service (CFS) of Natural Resources Canada and their collaborators to provide guidance on future research needs, improving our understanding of post-disturbance recovery in a Canadian context. To achieve our objective, we collected and classified peer-reviewed and non-published literature produced by the CFS between 1998 and 2020 that concerned post-disturbance ecology. We focused on research addressing natural or anthropogenic disturbances, such as wildfires, pest outbreaks, windthrows, forest management, seismic lines, and those that studied processes related to soil, vegetation, fauna, hydrology, and microbial communities. We found that forest harvesting was the disturbance most studied by CFS between 1998 and 2020, followed by fire. Despite the fact that large, forested areas are affected annually by pests, studies on recovery after pest outbreaks were scarce. Other disturbances, such as mining and seismic lines or other abiotic disturbances were rare in CFS literature. Most studies (70%) examined changes in vegetation related to forest management and fire and they were mainly focussed on post-disturbance tree regeneration success. Post-disturbance changes in understory species diversity were also well-studied. Our results provide a geographic overview of CFS research on post-disturbance recovery in Canada and enable the identification of key knowledge gaps. Notably, research focusing on recovery after natural disturbances was underrepresented in the assessed literature compared to studies centered around harvesting. Long-term research sites, chronosequences that substitute space for time, and studies focused on consecutive disturbances are especially important to maintain and establish sustainable forest management strategies in the face of climate change. [ABSTRACT FROM AUTHOR]

Conserving large intact forest landscapes (IFLs) is one forest management strategy to mitigate industrial impacts on the environment. Measuring the IFL inventory at national scales has also been proposed as a means of assessing the conservation status at global scales. This paper explores the relationship between fire regimes and the size of intact forest landscapes required to meet specific conservation targets. In this paper, we demonstrate that variation in fire regimes results in changes in the minimum size of IFL required to meet habitat targets. In addition, minimum IFL size is also dependent on the nature of the habitat targets. Larger IFLs are required to improve likelihood of providing sufficient older habitat. There is significant risk of not meeting older forest age-class targets at higher annual area burned (AAB) rates, especially under climate change. In general, there is more risk of not meeting habitat targets associated with smaller IFLs, higher annual area burned (both due to spatial differences and between historical and projected burn rates under climate change), and for provision of older forests. We used habitat age-related targets as outlined in the recovery strategy for woodland caribou as an example to demonstrate the usefulness of this type of simulation experiment and risk curves to identify appropriate IFL size along a gradient of natural disturbance intensity. [ABSTRACT FROM AUTHOR]

In a recently published article Sleep et al. () suggested that 30-yr declines in Canada warbler (1975-2005) based on Breeding Bird Survey (BBS) data could be attributed to 30-yr declines in spruce budworm through a series of analyses based principally on correlations. We demonstrate that the relationship does not hold when a longer-term data set (1968-2008) is used for the analysis. Sleep et al. () also demonstrated a positive relationship between correlations of Canada warbler abundance and time and spruce budworm defoliation and time using provincial data sets. We examined the underlying BBS data and found that there were insufficient observations of Canada warbler in the western provinces (Alberta and Manitoba) to support the conclusion because most Canada warbler observations occurred far (>100 km) from any budworm defoliation. As well, we used a density-dependent stochastic population growth model as proposed by Sleep et al. () and found only 2 significant relationships (Nova Scotia, Alberta) between Canada warbler population growth rate and budworm defoliation at the provincial scale. We conclude that little analytical evidence exists to support the idea that Canada warbler decline is a function of spruce budworm decline. © 2011 The Wildlife Society. [ABSTRACT FROM AUTHOR]

Salamanders have been identified as potential indicators of sustainable forest management in boreal Ontario, Canada. However, little information is available on their distribution, abundance, and habitat associations within the boreal forests on which to base a monitoring program. We surveyed salamanders near White River, Ontario, and related their distribution to climate and vegetation information and to habitat suitability models currently used for forest planning within the region. Primarily red-backed salamanders (Plethodon cinereus Green) and blue-spotted salamanders (Ambystoma laterale Hallowell) were recorded, although both were observed in low numbers and captures varied spatially and temporally. Capture rates were 3–7 times lower for P. cinereus than has been reported elsewhere. Trend monitoring will be expensive and have low power to detect significant declines over moderate time frames unless capture rates can be doubled and within-site variability in capture rates halved. We found few strong habitat relationships using either coverboard or pitfall trap data. Plethodon cinereus was negatively correlated with the volume of downed wood, which has been noted in other regions and may be an artefact of the coverboard survey technique. Further focused studies in the boreal forest are required to support the use of both habitat supply models and trend analysis to monitor salamander populations. [ABSTRACT FROM AUTHOR]

Simple Summary: Cages preventing access to birds were used to measure the rate of predation by birds in a spruce budworm population during the decline of an outbreak. Three species of budworm-feeding warblers were involved in this predation on larvae and pupae. It was found that bird predation is a very important source of mortality in declining spruce budworm populations, and that bird foraging behavior changes as budworm prey become rare at the end of the outbreak. The impact of avian predation on a declining population of the spruce budworm, Choristoneura fumifereana (Clem.), was measured using single-tree exclosure cages in a mature stand of balsam fir, Abies balsamea (L.), and white spruce, Picea glauca (Moench.) Voss. Bird population censuses and observations of foraging and nest-feeding activity were also made to determine the response of budworm-linked warblers to decreasing food availability. Seasonal patterns of foraging. as well as foraging success in the declining prey population was compared to similar information from birds observed in another stand where the spruce budworm population was rising. Avian predation was an important source of mortality between the 4th instar and moth emergence in the declining outbreak population. Mortality by predation increased from negligible to over 98% as budworm density dropped from 100 to <1 larva/kg of host foliage, over 3 years. Calculations based on nest-feeding activity and basic metabolic demands support these observed rates. Seasonal and yearly differences in predation rates observed between the two host-tree species correspond to equivalent shifts in bird foraging behavior in response to dropping insect density. In particular, a preference for searching on white spruce disappeared, although budworm-linked birds remained more efficient at finding food on this plant. The ability to change foraging behavior as prey density dropped differed between bird species. [ABSTRACT FROM AUTHOR]

Abstract: International and Canadian national and provincial level policy have proposed the use of criteria and indicators to examine the sustainability of renewable resource management. Species suitable as ecological indicators are those whose biology are sensitive to disturbance and therefore demonstrate a negative effect of management on the processes or functioning of the ecosystem. Ground dwelling invertebrates such as carabid beetles and spiders have strong potential as ecological indicators as they are readily surveyed in sufficient numbers for meaningful conclusions to be drawn, have a stable taxonomy and, at least in the case of ground beetles, are readily identified. They are good local scale indicators of ecosystem disturbance in forested landscapes at both the short and long time scales, responding to both clearcut logging and fire differently. Ground beetles and spiders in boreal Canada may not be good indicators of disturbance at landscape scales, as little response to the creation of forest edges and habitat fragmentation has so far been observed. We propose that these bioindicators be used as part of local-level validation monitoring to test hypotheses about disturbance impacts. In this way, bioindicators are used in a research setting to evaluate silvicultural practices, providing a rating of their sustainability for a given broad forest type grouping. [Copyright &y& Elsevier]

Mechanisms that have been proposed to explain the relationship between abundance (mean abundance at occupied sites) and distribution (proportion of sites occupied) have been based on (1) differences among species that affect either their ability to exploit resources or theirability to move through the landscape, (2) differences in species' landscapes that effect rates of successful dispersal of individuals, or (3) statistical arguments. Existence of an intra-specific abundance-distribution relationship where species differences can not be a factor would provide evidence that differences in species' landscapes likely contribute to the inter-specific abundance-distribution relationship. We examined the intra-specific relationship between abundance and distribution for 20 species of boreal forest songbirds. Abundance and distribution were calculated for each species in 52 to 119 locations over an area of 300 km x 100 km of northwestern Ontario. Based onseparate regressions, 16 of the species demonstrated significant positive relationships between abundance and distribution at alpha = 0.05. The weighted mean partial correlation for all species combined wasgreater than zero (P < 0.05). Meta-analysis indicated that there is no significant variation in the abundance-distribution correlation among species. This study provides evidence that amount of habitat within a landscape contributes to a positive intra-specific abundance-distribution relationship and therefore suggests that this factor could also contribute to the positive abundance-distribution relationship that is commonly found among species within an assemblage. [ABSTRACT FROM AUTHOR]

The management of forest ecosystems for sustainabil-ity requires knowledge of the abundance and distribution of all resources, including wood and wildlife, and the ability to predict the impact of management on these resources. Spatially explicit inventories for wildlife are lacking for the vast majority of species. We propose, with example, a method of rapid habitat assessment which can be conducted with available data to produce a spatially explicit inventory of habitat for a species. Information from the literature and some census data were used to construct a simple model of potential habitat for a boreal forest songbird. Available spatial data, including landcover from Landsat TM data, and a digital elevation model, were used to map the distribution of key habitat characteristics onto the landscape. We argue for the development of these preliminary wildlife habitat models using habitat characteristics that are map-pable with currently available remotely sensed data. Given the current trend toward the development of large scale databases of topography and extant land cover, spatially explicit potential habitat models can be efficiently and inexpensively developed to provide a framework for incorporating wildlife habitat into forest management. The relationships between rapid habitat assessment, long-term studies, monitoring, and population viability analysis are discussed. [ABSTRACT FROM PUBLISHER]

Studies the behavioral patterns of extra-pair copulations in tree swallows. Initiation by male; Cases where females solicit extra-pair copulation; Possible benefits and costs of extra-pair copulation.

Discusses the copulation behavior of the tree swallow. Paternity assurance in the presence of sperm competition; Idea that female tree swallows dictate to some extent when copulations occur such that males do not necessarily copulate at times that are optimal for assuring paternity. Extra-pair copulations; Higher copulation attempt rates; Dense nesting conditions; Males attempting to protect their paternity.

Fungi are primary agents of coarse woody debris (CWD) decay in boreal forests, playing an essential role in nutrient cycling and carbon storage. We compared fungal community assemblages using alpha and beta diversity metrics, and physical and chemical properties of CWD across three tree species (trembling aspen [Populus tremuloides], black spruce [Picea mariana], and jack pine [Pinus banksiana]), five decay classes, and two stand development stages, differing in time since stand replacing disturbance in Ontario's boreal forest region. We sampled 180 individual CWD logs from 6 independent stands, with 3 replicates per each species × decay class combination at each site. Using high-throughput sequencing of marker DNA, we found that fungal community structure significantly differed across tree species, decay stage, and stand age. Fungal diversity was highest in decay class 4 CWD. We found that Mn and K concentrations, total carbon, C/N ratio, N/P ratio, and moisture content were important predictors of fungal composition across CWD species and/or decay stage. This study suggests that forest management guidelines that consider both deadwood quantity and quality will support a broader range of fungal species and communities through post-disturbance stand development. [ABSTRACT FROM AUTHOR]

Forest biomass harvest has the potential to provide feedstocks for energy production to offset fossil fuel consumption. However, concerns have been raised regarding the ecological sustainability of removing additional biomass from forests, in particular the impacts on biodiversity. In this paper, we used a suite of ground-dwelling arthropod taxa (ground beetles, spiders, and rove beetles) to measure community compositional changes along a gradient of biomass removal treatments 7 years postharvest, and compared against reference. Based on multivariate regression trees, changes in species composition reflected the intensity gradient of the biomass removal treatments or stand attributes associated with the level of forest floor disturbance across all arthropod groups. For each arthropod group, changes in composition were defined primarily by reductions or loss of abundant forest associated species and increases in the number and abundance of species associated with more xeric conditions and increased disturbance intensity. There were no differences between full-tree and tree-length treatments. Overall, results indicated a strong arthropod response to the removal of overstory, forest floor disturbance, and reductions in understory cover mostly resulting from the glyphosate applications. Arthropod recovery would benefit from overstory retention, reduction in forest floor disturbance, and judicious use of glyphosate. [ABSTRACT FROM AUTHOR]

Abstract: Insect outbreaks are major natural disturbance events that affect communities of forest birds, either directly by affecting the food supply or indirectly by changing the vegetation composition of forest canopies. An examination of correlations between measures of bird and insect abundance across different spatial scales and over varying time lag effects may provide insight into underlying mechanisms. We developed a hierarchical Bayesian model to assess correlations between counts of eight warbler species from the Breeding Bird Survey in eastern Canada, 1966 to 2009, with the presence of spruce budworm (Choristoneura fumiferana Clem.) at immediate local scales and time‐lagged regional scales, as measured by extent of defoliation on host tree species. Budworm‐associated species Cape May warbler (Setophaga tigrina), bay‐breasted warbler (Setophaga castanea), and Tennessee warbler (Oreothlypis peregrina) responded strongly and positively to both local and regional effects. In contrast, non‐budworm‐associated species, Blackburnian warbler (Setophaga fusca), magnolia warbler (Setophaga magnolia), Canada warbler (Cardellina canadensis), black‐throated blue warbler (Setophaga caerulescens), and black‐throated green warbler (Setophaga virens), only responded to regional effects in a manner that varied across eastern Canada. The complex responses by forest birds to insect outbreaks involve both increased numerical responses to food supply and to longer term responses to changes in forest structure and composition. These effects can vary across spatial scales and be captured in hierarchical population models, which can serve to disentangle common trends from data when examining drivers of population dynamics like forest management or climate change. [ABSTRACT FROM AUTHOR]

Wildfire is a natural disturbance in boreal forest systems that has been predicted to increase in frequency, intensity, and extent due to climate change. Most studies tend to assess the recovery of one component of the community at a time but here we use DNA metabarcoding to simultaneously monitor soil bacteria, fungi, and arthropods along an 85-year chronosequence following wildfire in jack pine-dominated ecosites. We describe soil successional and community assembly processes to better inform sustainable forest management practices. Soil taxa showed different recovery trajectories following wildfire. Bacteria shared a large core community across stand development stages (~ 95–97% of their unique sequences) and appeared to recover relatively quickly by crown closure. By comparison fungi and arthropods shared smaller core communities (64–77% and 68–69%, respectively) and each stage appeared to support unique biodiversity. We show the importance of maintaining a mosaic ecosystem that represents each stand development stage to maintain the full suite of biodiversity in soils following wildfire, especially for fungi and arthropods. These results will provide a useful baseline for comparison when assessing the effects of human disturbance such as harvest or for assessing the effects of more frequent wildfire events due to climate change. [ABSTRACT FROM AUTHOR]

The management of forest ecosystems for sustainability requires knowledge of the abundance and distribution of all resources, including wood and wildlife, and the ability to predict the impact of managementon these resources. Spatially explicit inventories for wildlife are lacking for the vast majority of species. We propose, with example, amethod of rapid habitat assessment which can be conducted with available data to produce a spatially explicit inventory of habitat for a species. Information from the literature and some census data were used to construct a simple model of potential habitat for a boreal forest songbird. Available spatial data, including landcover from LandsatTM data, and a digital elevation model, were used to map the distribution of key habitat characteristics onto the landscape. We argue forthe development of these preliminary wildlife habitat models using habitat characteristics that are mappable with currently available remotely sensed data. Given the current trend toward the development of large scale databases of topography and extant land cover, spatially explicit potential habitat models can be efficiently and inexpensively developed to provide a framework for incorporating wildlife habitatinto forest management. The relationships between rapid habitat assessment, long-term studies, monitoring, and population viability analysis are discussed. [ABSTRACT FROM AUTHOR]

In Canada, the combustion of forest biomass for bioenergy production has been increasing with an associated increase in residual wood ash. Wood ash is typically landfilled as waste but there is growing interest in applying wood ash to the soils of commercial forests. Ideally, wood ash supplies nutrients that may have been removed through biomass harvesting, increases soil pH, which improves nutrient availability, and potentially improves site productivity, but there is also potential for detrimental effects, such as toxicity, that impair soil functions. The objective of this study was to investigate the effects of wood ash application on soil organic matter attributes at eight experimental sites across Canada that are examining the effects of wood ash application on site fertility, productivity, and soil biodiversity. Wood ash application had an effect on total carbon (TC) and total nitrogen, microbial biomass carbon (MBC), hot water extractable carbon (HWEC), mineralizable C, sand size C, and HWEC and MBC normalized to TC, but changes were typically restricted to single sites or differed in their direction, that is, positive or negative. Based on the limited and inconsistent effects of ash on established indictors of soil quality measured in this study, there does not appear to be any advantageous or detrimental effects of adding wood ash to forest soil quality. Wood ash generation from bioenergy production is increasing and is often landfilled when it could be land applied to improve soil. Wood ash is alkaline and contains nutrients essential to plant growth, which may maintain or enhance soil quality. Across a broad geographic gradient, there were limited effects of wood ash application to soils at eight sites in Canada on the measured attributes of soil quality, which suggests that soil quality is not affected by wood ash application. Wood ash generation is growing and when it makes economic sense to apply it to forest soils, it should be encouraged. [ABSTRACT FROM AUTHOR]

There is interest in utilizing wood ash as an amendment in forestry operations as a mechanism to return nutrients to soils that are removed during harvesting, with the added benefit of diverting this bioenergy waste material from landfill sites. Existing studies have not arrived at a consensus on what the effects of wood ash amendments are on soil biota. We collected forest soil samples from studies in managed forests across Canada that were amended with wood ash to evaluate the effects on arthropod, bacterial and fungal communities using metabarcoding of F230, 16S, 18S and ITS2 sequences as well as enzyme analyses to assess its effects on soil biotic function. Ash amendment did not result in consistent effects across sites, and those effects that were detected were small. Overall, this study suggests that ash amendment applied to managed forest systems in amounts (up to 20 Mg ha−1) applied across the 8 study sties had little to no detectable effects on soil biotic community structure or function. When effects were detected, they were small, and site-specific. These non-results support the application of wood ash to harvested forest sites to replace macronutrients (e.g., calcium) removed by logging operations, thereby diverting it from landfill sites, and potentially increasing stand productivity. [ABSTRACT FROM AUTHOR]

Direct and indirect effects of habitat modification and changes in biotic interactions should be taken into consideration to understand the ecological consequences of forest anthropogenic disturbance on forest ecosystems. Few empirical studies assess indirect effects and consider multiple trophic levels, but recent statistical and theoretical advances provide new paths to do so. Here, we investigate direct and indirect effects of anthropogenic disturbances on multi-trophic soil communities in a boreal forest. We assessed the short term (2 years) abiotic and biotic responses to two anthropogenic disturbance intensities: conventional harvesting and harvesting followed by organic matter removal. We quantified the changes on eight groups of species, including vegetation and soil fauna, and their potential effects on leaf litter decomposition. We used a trait-based approach and structural equation modeling to quantify direct and indirect effects of disturbance intensity on environmental conditions, functional responses of the above and below ground biotic communities and leaf litter decomposition. Forest disturbance intensity was found to have a bottom-up effect on species community composition, from lower trophic levels (for example, detritivorous springtails) up to soil fauna top predators (for example, running spiders). Our results suggested some impacts of disturbance on leaf litter decomposition through changes in faunal communities. Our study shows that a multi-trophic assessment of disturbance impacts provides an integrative understanding of ecosystem responses to environmental change. [ABSTRACT FROM AUTHOR]

We evaluated the utility of combining metapopulation models with landscape-level forest-dynamics models to assess the sustainability of forest management practices. We used the Brown Creeper (Certhia americana ) in the boreal forests of northern Ontario as a case study. We selected the Brown Creeper as a potential indicator of sustainability because it is relatively common in the region but is dependent on snags and old trees for nesting and foraging; hence, it may be sensitive to timber harvesting. For the modeling we used RAMAS Landscape, a software package that integrates RAMAS GIS, population-modeling software, and LANDIS, forest-dynamics modeling software. Predictions about the future floristic composition and structure of the landscape under a variety of management and natural disturbance scenarios were derived using LANDIS. We modeled eight alternative forest management scenarios, ranging in intensity from no timber harvesting and a natural fire regime to intensive timber harvesting with salvage logging after fire. We predicted the response of the Brown Creeper metapopulation over a 160-year period and used future population size and expected minimum population size to compare the sustainability of the various management scenarios. The modeling methods were easy to apply and model predictions were sensitive to the differences among management scenarios, indicating that these methods may be useful for assessing and ranking the sustainability of forest management options. Primary concerns about the method are the practical difficulties associated with incorporating fire stochasticity in prediction uncertainty and the number of model assumptions that must be made and tested with sensitivity analysis. We wrote new software to help quantify the contribution of landscape stochasticity to model prediction uncertainty. [ABSTRACT FROM AUTHOR]

Wood ash amendment to forest soils contributes to the sustainability of the growing bioenergy industry, not only through decreased wood ash waste disposal in landfills but also by increasing soil/site productivity and tree growth. However, tree growth studies to date have reported variable responses to wood ash, highlighting the need to identify proper application rates under various soil/site conditions to maximize their benefits. We explored the influence of tree species, wood ash nutrient application rates, time since application, stand development stage, and initial (i.e., before wood ash application) soil pH and N on short‐term tree growth response to wood ash amendment across eight unique study sites spanning five Canadian Provinces. Jack pine (Pinus banksiana Lamb) had the most positive response to wood ash amendment compared to white (Picea glauca Moench), hybrid (Picea engelmannii x glauca Parry), and black spruce (Picea mariana Miller), where increasing nutrient application rates increased height growth response. In comparison, black spruce had the most negative response to wood ash amendment, where increasing nutrient application rates slightly decreased height growth response. Site as a random effect explained additional variation, highlighting the importance of other unidentified site characteristics. By examining trends in short‐term growth response across multiple studies with variable site characteristics, we found growth response differed by tree species and nutrient application rates, and that jack pine is a promising candidate for wood ash amendment. These results contribute to our knowledge of optimal wood ash amendment practices and environmentally sustainable bioenergy production. [ABSTRACT FROM AUTHOR]

The Canadian boreal zone provides ecosystem services from local to global scales. Either directly or indirectly, demands for these services have and will continue to serve as drivers of change in the region. Here we present evidence for past, present, and potential future demand for maintaining nonprovisioning ecosystem services (NPrES), defined as indirect and nonmarketable services obtained from ecosystems as a driver of change in the boreal zone. Our evidence of demand stems from federal and provincial policies, actions by Indigenous peoples, and nongovernmental initiatives that aim to maintain the sustainability of natural resource extraction and ecosystem condition of the boreal. Presently, the demand for NPrES influences decisions related to natural resource development (e.g., forestry) that in turn impacts the condition of the boreal zone. Informed by the present conditions and past trends, three future scenarios to the year 2050 are presented that contrast in their trajectory—status quo, increased demand for NPrES, and decreased demand for NPrES. We also summarize the interactions among other drivers of change in the boreal and the synergies and trade-offs among the different types of demand for NPrES. Ultimately, sustainability of the boreal zone and the ecosystem services it provides will result from a complex suite of interacting drivers of change, where the balance of demands for provisioning and NPrES will continue to influence regional conditions. [ABSTRACT FROM AUTHOR]

Increased interest in biomass harvesting for bioenergetic applications has raised questions regarding the potential ecological consequences on forest biodiversity. Here we evaluate the initial changes in the abundance, species richness and community composition of rove (Staphylinidae) and ground beetles (Carabidae), immediately following 1) stem-only harvesting (SOH), in which logging debris (i.e., tree tops and branches) are retained on site, and 2) whole-tree harvesting (WTH), in which stems, tops and branches are removed in mature balsam fir stands in Quebec, Canada. Beetles were collected throughout the summer of 2011, one year following harvesting, using pitfall traps. Overall catch rates were greater in uncut forest (Control) than either stem-only or whole-tree harvested sites. Catch rates in WTH were greater than SOH sites. Uncut stands were characterized primarily by five species: Atheta capsularis, A. klagesi, A. strigosula, Tachinus fumipennis/frigidus complex (Staphylinidae) and to a lesser extent to Pterostichus punctatissimus (Carabidae). Increased catch rates in WTH sites, where post-harvest biomass was less, were attributable to increased catches of rove beetles Pseudopsis subulata, Quedius labradorensis and to a lesser extent Gabrius brevipennis. We were able to characterize differences in beetle assemblages between harvested and non-harvested plots as well as differences between whole tree (WTH) and stem only (SOH) harvested sites where logging residues had been removed or left following harvest. However, the overall assemblage response was largely a recapitulation of the responses of several abundant species. [ABSTRACT FROM AUTHOR]

Spatial models of population dynamics have been proposed as a useful method for predicting the impacts of environmental change on biodiversity. Here, we demonstrate advances in dynamic landscape metapopulation modelling and its use as a decision support tool for evaluating the impacts of forest management scenarios. This novel modelling framework incorporates both landscape and metapopulation model stochasticity and allows their relative contributions to model output variance to be characterized. It includes a detailed sensitivity analysis, allowing defensible uncertainty bounds and the prioritization of future data gathering to reduce model uncertainties. We demonstrate this framework by modelling the landscape-level impacts of eight forest management scenarios on the red-backed salamander ( Plethodon cinereus (Green, 1818)) in the boreal forest of Ontario, Canada, using the RAMAS Landscape package. The 100 year forest management scenarios ranged in intensity of timber harvesting and fire suppression. All scenarios including harvesting predicted decreases in salamander population size and the current style of forest management is predicted to produce a 9%-17% decrease in expected minimum population size compared with scenarios without harvesting. This method is amenable to incorporating many forms of environmental change and allows a meaningful treatment of uncertainty. [ABSTRACT FROM AUTHOR]

Terrestrial arthropod fauna have been suggested as a key indicator of ecological integrity in forest systems. Because phenotypic identification is expert-limited, a shift towards DNA metabarcoding could improve scalability and democratize the use of forest floor arthropods for biomonitoring applications. The objective of this study was to establish the level of field sampling and DNA extraction replication needed for arthropod biodiversity assessments from soil. Processing 15 individually collected soil samples recovered significantly higher median richness (488–614 sequence variants) than pooling the same number of samples (165–191 sequence variants) prior to DNA extraction, and we found no significant richness differences when using 1 or 3 pooled DNA extractions. Beta diversity was robust to changes in methodological regimes. Though our ability to identify taxa to species rank was limited, we were able to use arthropod COI metabarcodes from forest soil to assess richness, distinguish among sites, and recover site indicators based on unnamed exact sequence variants. Our results highlight the need to continue DNA barcoding local taxa during COI metabarcoding studies to help build reference databases. All together, these sampling considerations support the use of soil arthropod COI metabarcoding as a scalable method for biomonitoring. [ABSTRACT FROM AUTHOR]