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In forest inventories, regression models are often applied to predict quantities such as biomass at the level of sampling units. In this paper, we propose a model-based inference framework for combining sampling and model errors in the variance estimation. It was applied to airborne laser (LiDAR) data sets from Hedmark County, Norway, where the model error proportion of the total variance was found to be large for both scanning (airborne laser scanning) and profiling LiDAR when biomass was estimated. With profiling LiDAR, the model error variance component for the entire county was as large as 71% whereas for airborne laser scanning, it was 43% of the total variance. Partly, this reflects the better accuracy of the pixel-based regression models estimated from scanner data as compared with the models estimated from profiler data. The framework proposed in our study can be applied in all types of sample surveys where model-based predictions are made at the level of individual sampling units. Especially, it should be useful in cases where model-assisted inference cannot be applied due to the lack of a probability sample from the target population or due to problems of correctly matching observations of auxiliary and target variables.

The predicted climate warming and more frequent and longer droughts are expected to produce potentially severe water stresses in the boreal forest. The aim of this experiment was to study the effect of a summer drought on xylem phenology and anatomy of mature black spruce ( Picea mariana (Mill.) BSP) trees in their natural environment. The trees were excluded from rain during June–September 2010 by the installation of under-canopy roofs in four sites of the boreal forest of Quebec. Xylem phenology, stem radius variations, and physiological traits of treated and control trees were monitored at short time resolution. At the end of the growth season, cell characteristics were measured. The rain exclusion reduced the cell area of the xylem, but no significant change was observed in cell wall thickness, cell production, or phenology. Stem radius variations of the treated trees were lower but followed the same pattern as the control. After removal of the exclusion, trees and soil quickly recovered their normal water status. One summer of drought led to the formation of smaller tracheids but showed that black spruce is resistant to this rain exclusion treatment. This is likely due to the ability to collect water from sources other than the superficial soil horizon.

Increasing temperatures, precipitation extremes, and other anthropogenic influences (pollutant deposition, in­ creasing carbon dioxide) will influence future forest composition and productivity in the northeastern United States and eastern Canada. This synthesis of empirical and modeling studies includes tree DNA evidence suggesting tree migrations since the last glaciation were much slower, at least under postglacial conditions, than is needed to keep up with current and future climate warming. Exceedances of US and Canadian ozone air quality standards are apparent and offset C02-induced gains in biomass and predispose trees to other stresses. The deposition of nitrogen and sulfate in the northeastern United States changes forest nutrient availability and retention, reduces reproductive success and frost hardiness, causes physical damage to leaf surfaces, and alters performance of forest pests and diseases. These interacting stresses may increase future tree declines and ecosystem disturbances during transition to a warmer climate. Recent modeling work predicts warmer cli­ mates will increase suitable habitat (not necessarily actual distribution) for most tree species in the northeastern United States. Species whose habitat is declining in the northeastern United States currently occur in Canadian forests and may ex­ pand northward with warming. Paleoecological studies suggest local factors may interact with, even overwhelm, climatic effects, causing lags and thresholds leading to sudden large shifts in vegetation. Resume: L'augmentation des temperatures, les extremes de precipitation et d'autres facteurs anthropogeniques (les depots d'agents polluants, l'augmentation du dioxyde de carbone) influenceront la composition et la productivite future des forets du nord-est des Etats-Unis et de l'est du Canada. Cette synthese d'etudes empiriques et de modelisation inclut des preuves basees sur I' ADN des arbres qui indiquent que les migrations d'arbres depuis la derniere glaciation ont ete beaucoup plus lentes, du moins dans les conditions qui ont suivi la glaciation, qu'elles devraient l'etre pour suivre le rythme du re­ chauffement actuel et futur du climat. Les depassements des normes de qualite de l'air des Etats-Unis et du Canada pour l'ozone sont apparents; ils annulent les gains de biomasse dus au C02- et predisposent les arbres a d'autres stress. Les de­ pots d'azote et de sulfates dans le nord-est modifient la disponibilite et la retention des nutriments dans les forets, redui­ sent le succes de reproduction et la resistance au gel, causent des dommages physiques a la surface des feuilles et modifient la performance des organismes nuisibles et des maladies des arbres. Ces stress qui interagissent les uns avec les autres pourraient accentuer le deperissement des arbres et la perturbation des ecosystemes durant la periode de transition vers un climat plus chaud. Des travaux recents de modelisation predisent que des conditions climatiques plus chaudes aug­ menteront les habitats (pas necessairernent l'aire de repartition actuelle) qui conviennent ala plupart des especes d'arbres dans le nord-est des Etats-Unis. Des especes dont l'habitat est en declin aux Etats-Unis sont presentes dans les forets cana­ diennes aujourd'hui et pourraient s'etendre vers le nord avec le rechauffement. Des etudes paleoecologiques indiquent que des facteurs locaux pourraient interagir avec les effets du climat, voir meme les eclipser, causant des decalages et des seuils entrainant des changements soudains et importants dans la vegetation. (Traduit par la Redaction)

Due to the high amount of low-quality hardwoods harvested during selection cuts, the forest industry has been facing a decline in profit margins. One possible solution for utilizing the low-quality raw material is the production of extracts. The objective of this work was to estimate to what extent the inclusion of betulin in the traditional wood products portfolio could extend the profitability of a hardwood value chain. The profitability of a selection cut was assessed from the sawmill perspective, followed by an evaluation of the potential financial gain of producing betulin. Finally, the inclusion of betulin in a value chain was assessed. Results showed that the profitability of selection cuts was very low in some forest stands. The sensitivity analysis demonstrated that, among selected costs and revenues, profit was more sensitive to variations in the value of coproducts. If a fraction of coproducts volume was used to extract betulin, it would be sufficient to generate enough revenue to offset the total costs; however, a major constraint was the small size of the current betulin market, with annual sales not exceeding 1000 kg. Despite that, results demonstrate the potentially strong contribution of high value added extracts to the profitability of the forest value chain.

Traditionally, most applications in the initial stage of forest supply chain deal with sawlogs to sawmills, pulpwood to pulp or paper mills and forest residues to heating plants. However, in the past decades, soaring prices of fossil fuel, global awareness about CO2 emission and increasing attention to domestic resource security have boosted the development of alternative renewable energy, among which forest bioenergy is the most promising and feasible choice for medium- and large-scale heating and electricity generation. Different subsidies and incentive policies for green energy further promote the utilization of forest bioenergy. As a result, there is a trend that pulpwood may be forwarded to heating plants as complementary forest bioenergy. Though pulpwood is more expensive than forest residues, it is more efficient to transport and has higher energy content. The competition between traditional forest industries and wood-energy facilities, expected to grow in the future, is very sensitive for the forest companies as they are involved in all activities. In this paper, we develop a model that all raw materials in the forest, i.e. sawlogs, pulpwood and forest residues, and byproducts from sawmills, i.e. wood chips and bark, exist in an integrated market where pulpwood can be sent to heating plants as bioenergy. It represents a multi-period multi-commodity network planning problem with multiple sources of supply, i.e. pre-selected harvest areas, and multiple kinds of destination, i.e. sawmills, pulp mills and heating plants. The decisions incorporate purchasing the raw materials in harvest areas, reassigning byproducts from sawmills, transporting those assortments to different points for chipping, storing, wood-processing or wood-fired, and replenishing fossil fuel when necessary. Moreover, different from the classic wood procurement problem, we take the unit purchasing costs of raw materials as variables, on which the corresponding supplies of different assortments linearly depend. With this price mechanism, the popularity of harvest areas can be distinguished. The objective of the problem is to minimize the total cost for the integrated market including the purchasing cost of raw materials. Therefore, the model is a quadratic programming (QP) problem with a quadratic objective function and linear constraints. A large case study in southern Sweden under different scenario assumptions is implemented to simulate the integrated market and to study how price restriction, market regulation, demand fluctuation, policy implementation and exogenous change in price for fossil fuel will influence the entire wood flows. Pair-wise comparisons show that in the integrated market, competition for raw materials between forest bioenergy facilities and traditional forest industries pushes up the purchasing costs of pulpwood. The results also demonstrate that resources can be effectively utilized with the price mechanism in supply market. The overall energy value of forest bioenergy delivered to heating plants is 23% more than the amount in the situation when volume and unit purchasing cost of raw materials are fixed.

Technological development has enabled the production of new value-added products from lignocellulosic residues such as lignin. This has allowed the forest industry to diversify its product portfolio and maximize the economic returns from feedstock, while simultaneously working towards sustainable alternatives to petroleum-based products. Although previous research has explored industrial-scale production opportunities, many challenges persist, including the cost of woody biomass and its supply chain reliability. While numerous studies have addressed these issues, their emphasis has traditionally been on bioenergy, with little focus on biochemical, biomaterials, and bioproducts. This review seeks to address this gap through a systematic study of the work recently reported by researchers. A lot of work has been published from United States and Canada with an emphasis on bioenergy production (84.8%), 4.6% of the work is focused on biomass to materials and chemicals, and 10.6% addressed both. Between 2012 and 2015, the majority of published research focused on biomass to materials and chemicals and both biomass to energy and biomass to materials and chemicals. This fact highlights recent interests in diversified biorefinery portfolios. However, further work concerning forest biomass supply chain optimization and new high-value bio-based materials and chemicals is necessary.

Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) were monitored for 4 years following three wildfires. Logis- tic regression analyses were used to develop models predicting the probability of attack by Douglas-fir beetle (Dendroc- tonus pseudotsugae Hopkins, 1905) and the probability of Douglas-fir mortality within 4 years following fire. Percent crown volume scorched (crown scorch), cambium injury, diameter at breast height (DBH), and stand density index for Douglas-fir were most important for predicting Douglas-fir beetle attacks. A nonlinear relationship between crown scorch and cambium injury was observed, suggesting that beetles did not preferentially attack trees with both maximum crown scorch and cambium injury, but rather at some intermediate level. Beetles were attracted to trees with high levels of crown scorch, but not cambium injury, 1 and 2 years following fire. Crown scorch, cambium injury, DBH, and presence/absence of beetle attack were the most important variables for predicting postfire Douglas-fir mortality. As DBH increased, the pre- dicted probability of mortality decreased for unattacked trees but increased for attacked trees. Field sampling suggested that ocular estimates of bark char may not be a reliable predictor of cambium injury. Our results emphasize the important role of Douglas-fir beetle in tree mortality patterns following fire, and the models offer improved prediction of Douglas-fir mortality for use in areas with or without Douglas-fir beetle populations. Resume´ : Des douglas de Menzies (Pseudotsuga menziesii (Mirb.) Franco) ont etesuivis pendant 4 ans a la suite de trois incendies de foret. Des analyses de regression logistique ont eteutilisees pour elaborer des modeles de prediction de la probabilited'une attaque du dendroctone du douglas (Dendroctonus pseudotsugae Hopkins, 1905) et de la probabiliteque le douglas de Menzies meure dans les quatre annees suivant un feu. Le volume de cime roussi, les dommages au cambium, le diametre ahauteur de poitrine (DHP) et l'indice de densitedu peuplement de douglas de Menzies etaient les variables les plus importantes pour predire les attaques du dendroctone. Une relation non lineaire entre le roussissement de la cime et les dommages au cambium a eteobservee, ce qui signifie que les dendroctones n'attaquent pas de preference les arbres qui ont ala fois le maximum de dommages a la cime et au cambium mais plutot un niveau intermediaire quel- conque. Les dendroctones etaient attires par les arbres avec un degreelevede roussissement de la cime mais sans dom- mages au cambium, un et 2 ans apres un feu. Le roussissement de la cime, les dommages au cambium, le DHP et la presence ou l'absence d'attaques du dendroctone etaient les variables les plus importantes pour predire la probabiliteque le douglas de Menzies meure apres un feu. La probabiliteestimee de mortalitediminuait avec l'augmentation du DHP chez les arbres qui n'avaient pas eteattaques alors que la probabilitequ'un arbre meure augmentait avec l'augmentation du DHP chez les arbres qui avaient eteattaques. Des echantillons preleves sur le terrain indiquent que l'estimation oculaire d'une couche superficielle d'ecorce carbonisee pourrait ne pas etre un predicteur fiable de dommages au cambium. Nos re´- sultats font ressortir l'importance du role que joue le dendroctone du douglas dans les patrons de mortaliteapres un feu et les modeles offrent de meilleures predictions de la mortalitedu douglas de Menzies dans les zones avec ou sans popula- tions de dendroctone. (Traduit par la Redaction)

Parent and preflight-adult Douglas-fir beetles (Dendroctonuspseudotsugae Hopk., Coleoptera: Scolytidae) were collected from felled Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) trees. Fungi isolated from the beetles included blue-stain fungi, such as Ophiostomapseudotsugae (Rumbold) von Arx, Leptographiumterebrantis Barras & Perry, and Leptographiumabietinum (Peck) Wingfield; other ascomycetes, such as Graphium spp. and Leptographium spp.; yeasts; and unidentified basidiomycetes. All fungal cultures derived from parent beetles, preflight adults, beetle eggs, larvae, frass, and bark from galleries had yeasts present. Ophiostomapseudotsugae was isolated from 67% of the parent females, 19% of the parent males, and 100% of the preflight adults of both sexes collected from their pupal cells. Rinsing the beetles with 70% ethanol prior to fungus isolations reduced the frequency of all fungi, except yeasts. Parent and preflight adult beetles (of both sexes) were examined with a scanning electron microscope, where spores of O. pseudotsugae were visible in shallow pits on the elytra of both male and female beetles. Spores of other fungi were observed in shallow pits on elytra and in much smaller but deeper pits on the scutellum of both sexes. The results indicate a close association between Douglas-fir beetles and fungi, accompanied by anatomical differentiation on the beetles that allows the dissemination of blue-stain fungi to new Douglas-fir hosts and substrates.

Data on 2356 trees from 43 prescribed fires in Idaho, Montana, Oregon and Washington were used to model postfire tree mortality. Data were combined for seven species of conifers (Pseudotsuga menziesii, Larix occidentalis, Picea engelmannii, Pinus contorta, Abies lasiocarpa, Thuja plicata and Tsuga heterophylla) to develop binary logistic regression models for predicting the probability of mortality. Probability of mortality increased with percentage of the crown killed and decreased as bark thickness increased. Models are presented with and without species as a categorical variable. The models are applicable for assessing fire-caused mortality both of individual trees and in mixed conifer stands of the Pacific Northwest.

The study tests whether the lethal effect of overwintering Engelmann spruce seed in its O-horizon affects Douglas-fir, lodgepole pine and subalpine fir seeds and whether the O-horizons of the three associated species have the same lethal effect on seeds. All seed treatments of each species were stratified in petri dishes in the pure O-horizon (unsterilized and autoclaved) of each species. Seed treatments were untreated, 10% slurry of 50% Captan and powdered 75% Captan.All untreated seeds demonstrated the lethal quality of unsterilized Engelmann spruce O-horizon. Its effects on untreated seeds and powder treated seeds were as follows: Engelmann spruce seed 3.5 and 77.3% (germination of untreated and powdered respectively), subalpine fir seed 1.3 and 20.8, Douglas-fir seed 9.5 and 84.8 and lodgepole pine seed 11.9 and 85.7. Subalpine fir O-horizon was lethal to its own seeds but only moderately harmful to seeds of other species. Douglas-fir O-horizon had a significant adverse effect on its own seeds and was only moderately harmful to seeds of other species. Lodgepole pine O-horizon was almost neutral to all seeds. Autoclaving of the O-horizons and powder treatment of seeds produced similar results.

Thinning stands of lodgepole pine (Pinuscontorta Douglas var. latifolia Engelmann) is thought to increase vigor and thereby reduce susceptibility to mountain pine beetle (Dendroctonusponderosae Hopkins). Partial cut stands of lodgepole in the Kootenai and Lolo National forests, Montana, U.S.A., provided opportunity (i) to determine growth response of 76- to 102-year-old lodgepole pines following thinning and (ii) to test the hypothesis that vigor of residual trees infested and uninfested by beetles does not differ. Lodgepole pine stands receiving different partial cutting prescriptions were sampled. Characteristics measured for trees within the sample were diameter at breast height, grams of stem wood per square metre of foliage, periodic growth ratio, and leaf area. Trees in most treatments showed decreased growth the 1st year following thinning. The 1st year was followed by increased growth during the next 4 years. Of the tree characteristics measured, only dbh was significantly different on both forests between live trees and trees killed by the mountain pine beetle; the latter were larger (P

Forests are the locus of conflict in Canada, where the rights and interests of Indigenous peoples can collide with those of the province (Crown) and the forest industry. Efforts to achieve “forest justice” — or sufficient forest rights to meet the self-governance goals of Indigenous peoples, and in ways that ensure collective resilience — have typically been driven by the principle of reconciliation. In this paper, these “forest justice” efforts were examined through a tripartite justice theory, involving recognition, representation, and redistribution pathways. This paper documents that recognition involves Crown efforts to recognize Indigenous peoples’ forest rights, including ownership, and access and use rights; representation includes improved participation in forest governance; and redistribution covers the allocation of timber harvesting rights and forest lands to Indigenous peoples. This study documents that the bulk of “forest justice” activity is focused on the redistribution of timber harvesting licences, the volume of which has doubled over the last two decades. These three paths to justice must all be pursued together to deliver “forest justice”, and to move towards “reconciliation in the woods”. Recommendations are offered to support forest justice in practice.

Proponents of decentralized forest governance make a compelling case that community forest enterprises (CFEs) can aid in sustainable and equitable utilization of forest resources. The effectiveness of CFEs is thus dependent on their ability to balance social, environmental, and financial performance. In this paper, we examine the relationship between a commonly recommended differentiation strategy and CFE effectiveness. Using data obtained through a survey administered on 51 CFEs located in the Cascadia region (British Columbia province of Canada; and Oregon and Washington states of the United States), we find that CFEs pursuing a differentiation strategy are able to balance social, environmental, and financial objectives. Further, recognizing that all CFEs cannot pursue a differentiation strategy, and some may not even have a defined strategic orientation, the paper compares social, environmental, and financial performance of CFEs pursuing a differentiation strategy, a hybrid strategy (a combination of differentiation and cost leadership strategy), and no defined strategy. This analysis reveals that CFEs pursuing a hybrid strategy deliver better financial performance than those with no defined strategy but are similar to those pursuing a differentiation strategy.

Recently, the World Scientists’ Warning to Humanity: a Second Notice was issued in response to ongoing and largely unabated environmental degradation due to anthropogenic activities. In the warning, humanity is urged to practice more environmentally sustainable alternatives to business as usual to avoid potentially catastrophic outcomes. Following the success of their warning, the Alliance of World Scientists called for discipline-specific follow-up papers. This paper is an answer to that call for the topic of wildland fire. Across much of Canada and the world, wildfires are anticipated to increase in severity and frequency in response to anthropogenic activities. The world scientists’ second warning provides the opportunity for wildland fire researchers to raise the profile of the potential impacts that anthropogenic activities are likely to have on future fire regimes and, in return, what impacts future fire regimes may have on humanity. We discuss how wildfire is related to several issues of concern raised in the world scientists’ second warning, including climate change, human population growth, biodiversity and forests, and freshwater availability. Furthermore, we touch on the potential future health impacts and challenges to wildfire suppression and management in Canada. In essence, our wildfire scientists’ warning to humanity is that we, as a society, will have to learn to live with more fire on the landscape. We provide some recommendations on how we might move forward to prepare for and adapt to future wildfire regimes in Canada. Although this paper is primarily Canadian in focus, the concepts and information herein also draw from international examples and are of relevance globally.

In the managed forest of Canada, forest fires are actively suppressed through efficient initial attack capability; however, the impact of different factors on the suppression success remains to be understood. The aim of this paper was to analyze the influence of operational suppression objectives (fire detection, initial attack, and fire control) along with fire intensity, fuel type, fire ignition cause, year, workload, and homogeneous fire regime zones on the achievement of the fire suppression objective (fire < 3 ha) using the Forest Fire Protection Agency of Quebec (SOPFEU) as a case study. The overall success of the suppression objective was very high (88%) over the study period (1994–2015). Both detection and control had significant effects on the suppression success through their interaction with fuel type, ignition cause, fire intensity, and zone variables. When the suppression objective was not achieved, final fire size was influenced by control, fuel type, fire intensity, and zone. The paper highlights the importance of the operational objectives and of regional differences for both fire suppression success and final fire size. Our results can help forest fire protection agencies to better understand their wildland fire suppression systems for a better adaptation to the upcoming fire regime changes. We gratefully acknowledge the Société de protection des forêts contre le feu (SOPFEU) and Mélanie Desrochers for providing the databases for the study. We thank Yan Boulanger and Steve Cumming for their constructive comments on an earlier version of this paper. The authors are thankful to Isabelle Lamarre for improving the quality of the English text. Research funding was provided by the New Forests European project to A. Cardil and by a postdoctoral research scholarship from the FRQNT (Fonds de recherche du Québec – Nature et technologies) to M. Lorente.

We often hear about the resistance of First Nation (FN) communities to the industrial model of forestry, but we hear less about what they wish to achieve. Translating FN perspectives into concepts that are understood by the mainstream society can help inform current and future forest policies. Such translation can support initiatives that seek ways to increase FN participation in the forest sector. This paper documents one process of translation. It identifies the principles and objectives for forest-based development of the Essipit Innu First Nation in Quebec, Canada, reflective of the deep roots that anchor the Essipit to their territory. Based on participatory research carried out between January and July 2013, we identify 34 objectives folded into three core FN principles: Nutshimiu–Aitun (identity–territoriality), Mishkutunam (sharing–exchange), and Pakassitishun (responsibility–autonomy). Our analysis shows that the economic aims of the dominant forestry model are too narrow for FN communities. This paper contributes to expanding FN engagement in forestry through management and economic approaches that are better adapted to their culture and values.

High productivity in forest harvesting requires efficient forwarding. Planning is complicated by multiple choices of routes and their order, the number and types of assortments, the loading sequence, and pile organization at the landing. This paper develops and tests a decision support tool for forwarder routing with sequential co-loading of assortments. Input data are the harvester production file (including Global Navigation Satellite Systems tracking), placement of landing, and machine specifications. The trail network is generated from the harvester production data when devising routes to pick up all log piles, including specific assortments and volumes. Multiple assortments can be loaded along each route, and a certain loading sequence of assortments is preferred and (or) required. Sorting time during co-loading varies, depending on the assortment combinations and bunk loading pattern. Route planning is modeled using a set-partitioning problem, and the solution method is a metaheuristic based on repeated matching. In addition to routes and loading sequences, solutions include the organization of assortment piles at the landing, depending on the total volume of each assortment. The tool produces similar results to those attained by skilled forwarder operators on five clearcuts (3–11 ha) in northern Sweden, when the results are compared with data from actual forwarder production files.

Although ectomycorrhizal fungi play an important role in forest ecosystem functioning, they are usually not included in forest growth or ecosystem models. Simulation is hampered by two main issues: a lack of understanding of the ecological functioning of the ectomycorrhizal fungi and a lack of adequate basic data for parameterization and validation. Concerning these issues, much progress has been made during the past few years, but this information has not found its way into the forest and soil models. In this paper, state-of-the-art insight into ectomycorrhizal functioning and basic values are described in a manner transparent to nonspecialists and modelers, together with the existing models and model strategies. As such, this paper can be the starting point and the motivator to include ectomycorrhizal fungi into existing soil and forest ecosystem models.

Horvitz–Thompson-like stand density estimation is a method for estimating the stand density from tree crown objects extracted from airborne laser scanning data through individual tree detection. The estimator is based on stochastic geometry and mathematical morphology of the (planar) set formed by the detected tree crowns. This set is used to approximate the detection probabilities of trees. These probabilities are then used to calculate the estimate. The method includes a tuning parameter, which needs to be known to apply the method. We present a refinement of the method to allow more general detection conditions than those of previous papers. We also present and discuss the methods for estimating the tuning parameter of the estimator using a functional k-nearest neighbors method. We test the model fitting and prediction in two spatially separate data sets and examine the plot-level accuracy of estimation. The estimator produced a 13% lower RMSE (root-mean-square error) than the benchmark method in an external validation data set. We also analyze the effects of similarity and dissimilarity of training and validation data on the results.

In recent years, increasing attention has been drawn to improving productivity in logging passages while reducing negative impact on soil and water. The position of landings and extraction routes is crucial in these efforts, as it has a huge impact on efficient and sustainable forwarder passages. In this paper, we propose a two-phase approach to identify the best possible landing locations integrated with log extraction route design. The first phase identifies potential landing zones adjacent to forest roads. It considers practical restrictions such as slopes, stoniness, and closeness to infrastructure. The second phase uses an optimization model to evaluate the potential impact of each zone and aggregate zones, selecting one or two complete landings. This model is a relaxation of a formulation for an extraction route design; it is used to minimize a weighted objective of the total driving distance, avoid steep terrains and impact on soil and water. The proposed approach has been tested on a set of harvest areas in southern Sweden. The results not only show the potential to identify feasible landing zones but also identify a shorter driving distance and hence lower contractual cost with optimized positioning. The possibility to increase efficiency in forest operations by performing scenario analysis and thus forwarding distances with different landing sites is among the results.

Climate-smart forestry (CSF) is considered a promising approach for climate change adaptation and mitigation strategies, as highlighted in several European policy documents. This paper describes a prospective approach to introducing an incentive-based scheme to facilitate the implementation of CSF through a case study in Iceland. It is argued that the payments for ecosystem services (PES) scheme allows for effective CSF management and long-term sustainability if introduced in compliance with local, cultural, and social values. In a case study of an Icelandic afforestation programme, we conducted an institutional analysis of the PES scheme and assessed its effect on the sustainable provision of forest ecosystem services for the long term. We provide preliminary findings on the application of CSF in the 30-year-old Icelandic afforestation programme scheme. The perspectives of forest and policy experts, as well as local farmers participating in the scheme, were crucial for assessing the effectiveness of PES scheme performance in Iceland.

In this paper, we examine the implications of managing for sustained yield in a world characterized by growing risk and uncertainty. We review the history of sustained yield (SY) forestry in North America, with an emphasis on economic benefits and the persistence of the SY paradigm today, despite a publicized shift towards managing for a wider range of forest values called sustainable forest management (SFM). We show that current forest management goals around sustainability as well as SFM indicators are still predicated on maximizing harvest levels and timber flows. We build a simple model to explore the implications of SY under extreme (fat-tailed) risk assumptions to show that maximizing a level of harvest without adequately accounting for risk leads towards the depletion of the forest stock with a corresponding decline in the forest economy. We discuss these results in relation to real-world events such as the increase in catastrophic fires and pest outbreaks like the mountain pine beetle in Western Canada. We then examine the theoretical and practical implications that flow from this model and analysis.

Old growth is disappearing globally, with implications for biodiversity, forest resilience, and carbon storage; yet uncertainty remains about how much exists, partly because assessments stratify ecosystems differently, sometimes obscuring relevant patterns. This paper compares portrayals of British Columbia’s (BC) old-growth forest stratified in two ways: by biogeoclimatic variant, as per policy, and by relative site productivity. Our analyses confirm provincial government claims that about a quarter of BC’s forests are old growth but find that most of this area has low realized productivity, including subalpine and bog forests, and that less than 1% is highly productive old growth, growing large trees. Within biogeoclimatic variant, nearly half of high-productivity forest landscapes have less than 1% of the expected area of old forest. Low-productivity ecosystems are over-represented in protected forest. We suggest that the experiment of managing old growth solely by biogeoclimatic variant has failed and that current forest policy, in combination with timber harvesting priorities, does not maintain representative ecosystems, counter to the intent of both policy and international conventions. Stratifying old growth by relative productivity within biogeoclimatic variant seems an appropriate method to portray ecosystem representation, potentially increasing the probability of maintaining ecosystem resilience.

We celebrate the 50th anniversary of the Canadian Journal of Forest Research by reflecting on the considerable progress accomplished in select areas of Canadian wildland fire science over the past half century. Specifically, we discuss key developments and contributions in the creation of the Canadian Forest Fire Danger Rating System; the relationships between wildland fire and weather, climate, and climate change; fire ecology; operational decision support; and wildland fire management. We also discuss the evolution of wildland fire management in Banff National Park as a case study. We conclude by discussing some possible directions in future Canadian wildland fire research including the further evaluation of fire severity measurements and effects; the efficacy of fuel management treatments; climate change effects and mitigation; further refinement of models pertaining to fire risk analysis, fire behaviour, and fire weather; and the integration of forest management and ecological restoration with wildland fire risk reduction. Throughout the paper, we reference many contributions published in the Canadian Journal of Forest Research, which has been at the forefront of international wildland fire science.

The objective of this paper was to estimate the effect of either missing or dominated plants (those that developed poorly) in experiments evaluating progenies or clones of Eucalyptus. Additionally, it was to investigate whether the use of the area available per plant is a suitable strategy to mitigate the effect of missing plants. Lastly, it was to evaluate whether missing or dominated plants in the experiments affected the association between plant performance in a progeny trial (PT) and their respective clones in a clonal trial (CT). Five 5-year-old PTs and four 3-year-old CTs were used. The recorded trait was diameter at breast height (DBH). The area available per plant was used to carry out the adjustment, taking into consideration the absence of neighboring plants as well as dominated plants. It was found that with the level of missing plants below 20% in experiments, the adjustment using the area available per plant did not improve the efficiency of the selection of either PTs or CTs. The strategy of considering not only missing plants but also dominated plants is not beneficial for the adjustment.

Made available in DSpace on 2019-10-04T12:13:44Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-05-01 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Anglo American Arauco Arborgen Arcelor-Mittal Cenibra CMPC Comigo Copener Duratex Eldorado Fazenda Campo Bom Fibria Florestal Itaquari Forestal Oriental Gerdau GMR International Paper Jari Klabin Lwarcel Montes del Plata Plantar Rigesa Suzano Vallourec Veracel University of Sao Paulo Sao Paulo State University Federal University of Lavras Federal University of Rio Grande do Norte Colorado State University North Carolina State University USDA Forest Service Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Lack of generalized equations has prevailed in Brazil, because it is assumed that localized or climate-specific equations are needed. This study aimed to develop generalized stem taper and volume equations applicable to 11 eucalyptus clones and evaluate if climate variation impacts the accuracy of the estimates. A total of 693 trees evenly distributed across 11 clones at 21 sites were used for model fittings and predictive validation. The penalized mixed spline (PMS) approach was developed for predicting stem taper and volume along the stem profile. The Schumacher and Hall (1933) equation was used to predict total tree volume, while volume ratio equations were applied to predict merchantable volume. For every fitted equation, an annual climatic variable was included to assess the improvement in model performance. The overall results highlighted that climatic variation does not need to be accounted for in stem taper and volume modeling. All of the equations displayed desirable accuracy, but the generalized PMS equation may be preferred when the forestry enterprise looks to furnish a range of multiple forest products. The generalized total tree volume equation, combined with the ratio equations, is highly recommended when the forestry enterprise produces a single product. North Carolina State Univ, Dept Forestry & Environm Resources, Raleigh, NC 27695 USA Virginia Polytech Inst & State Univ, Dept Forest Resources & Environm Conservat, Blacksburg, VA 24061 USA Forestry Sci & Res Inst, BR-13415000 Sao Paulo, Brazil State Univ Sao Paulo, Dept Forest Sci, BR-18610034 Sao Paulo, Brazil State Univ Sao Paulo, Dept Forest Sci, BR-18610034 Sao Paulo, Brazil CNPq: 249979/2013-6

In this paper, we examine the transferability of airborne laser scanning (ALS) based models for individual-tree detection (ITD) from one ALS inventory area (A1) to two other areas (A2 and A3). All areas were located in eastern Finland less than 100 km from each other and were scanned using different ALS devices and parameters. The tree attributes of interest were diameter at breast height (Dbh), height (H), crown base height (Cbh), stem volume (V), and theoretical sawlog volume (Vlog) of Scots pine (Pinus sylvestris L.) with Dbh ≥ 16 cm. All trees were first segmented from the canopy height models, and various ALS metrics were derived for each segment. Then only the segments covering correctly detected pines were chosen for further inspection. The tree attributes were predicted using the k-nearest neighbor (k-NN) imputation. The results showed that the relative root mean square error (RMSE%) values increased for each attribute after the transfers. The RMSE% values were, for A1, A2, and A3, respectively: Dbh, 13.5%, 14.8%, and 18.1%; H, 3.2%, 5.9%, and 6.2%; Cbh, 13.3%, 15.3%, and 18.3%; V, 29.3%, 35.4%, and 39.1%; and Vlog, 38.2%, 54.4% and 51.8%. The observed values indicate that it may be possible to employ ALS-based tree-level k-NN models over different inventory areas without excessive reduction in accuracy, assuming that the tree species are known to be similar.

The challenges faced recently by the North American forest products industry have forced it to review many of its key operations. Implementing logistics centers for such a context may therefore help in allocating the wood fibre more efficiently and in reducing sorting and transportation costs. This paper aims to better understand the interaction between a forest logistics center and a complex forest network while exploring the business environment favoring the use of such a structure. A profit maximization model is proposed and applied to a real case in the Mauricie region in Quebec, Canada. A total of 18 groups of scenarios are tested, based on the use of a sort yard and of backhauling. Results show that a logistics center already in operation adds $0.52 in profits for each cubic metre of wood available for harvest (over 2 580 411 m3 per year) for the network under study ($1.4 million annually). A sensitivity analysis also highlights that higher prices and sorting error rates have the greatest impact on the logistics center’s profitability.

This paper presents a nationwide application of k-nearest neighbors (k-NN) to estimate growing stock volume per hectare for the Irish National Forest Estate using optical satellite imagery and fiel...

In this paper, we present an approach employing multiobjective optimization to support decision making in forest management planning under risk. The primary objectives are biodiversity and timber cash flow, evaluated from two perspectives: the expected value and the value-at-risk (VaR). In addition, the risk level for both the timber cash flow and biodiversity values are included as objectives. With our approach, we highlight the trade-off between the expected value and the VaR, as well as between the VaRs of the two objectives of interest. We employ an interactive method in which a decision maker iteratively provides preference information to find the most preferred management plan and learns about the interdependencies of the objectives at the same time. The method is illustrated with a case study in which biodiversity is assessed through an index calculated from the characteristics of the forest. Uncertainty is included both through modifying the input data according to the accuracy of current inventory methods and through growth model errors. This uncertainty is described using a set of 25 scenarios. Involving multiple components of risk is a highly relevant approach in multiobjective forestry; however, estimation of the uncertainty of biodiversity needs further attention.

In this paper, we report an investigation of how forest stand mixture may affect biomass allometric relationships in Norway spruce (Picea abies (L.) Karst.). Analysis of aboveground biomass data was conducted for 50 trees: 25 sample trees from a pure Norway spruce stand and 25 from a mixed stand of Norway spruce with European beech (Fagus sylvatica L.). ANCOVA results demonstrated that individual-tree biomass allometry of the pure stand significantly differed from that of the mixed stand. Allometric characteristics depended on the biomass component recorded and the type of biomass predictor used. When predicted by diameter at breast height and (or) height, the total aboveground biomass of mixed-stand trees was significantly less than that for pure-stand trees. This “apparent” lower aboveground biomass was attributed to the lower branch and needle biomass proportions of trees growing in mixed stand. The findings indicate that caution should be exercised when applying biomass allometric models developed from pure stands to predict tree biomass in mixed stands (and vice versa), as such data treatment may introduce significant bias.

The Russian Federation is one of many countries that have signed the Montreal Protocol and Pan-European Forest Process. These initiatives are aimed at harmonizing national forest inventory systems with criteria and indicators for sustainable forest management. In Russia, the classification of forest type is at the heart of national forest inventory systems. For various historical reasons, Russian scientific advancements in the field of forest typology remain little known in the rest of the world. This paper is aimed at addressing this deficiency. Here, we provide an overview of the main trends in the field of forest typology studies in the previous political states of the Russian Empire, the Soviet Union, and the Russian Federation from the end of the nineteenth century to the beginning of the twenty-first century. We detail the principles that formed the basis of the most significant forest type classifications. We also perform similarity and differences analyses comparing approaches used by members of different scientific schools in the field of forest typology. The historical relationship between ecological, phytocoenotic, genetic, and dynamic forest type classifications are discussed as well as the reasons for the prevalence of certain forest type classifications in different regions of Russia.

X-ray computed tomography (CT) of logs means possibilities for optimizing breakdown in sawmills. This depends on accurate detection of knots to assess internal quality. However, as logs are stored they dry to some extent, and this drying affects the density variation in the log, and therefore the X-ray images. For this reason it is hypothetically difficult to detect log features in partially dried logs using X-ray CT. This paper investigates the effect of improper heartwood-sapwood border detection, possibly due to partial drying, on knot detection in jack pine (Pinus banksiana Lamb.) and white spruce (Picea glauca (Moench) Voss) logs from New Brunswick, Canada. An automatic knot detection algorithm was compared to manual reference knot measurements, and the results showed that knot detection was affected by detected heartwood shape. It was also shown that logs can be sorted into two groups based on how well the heartwood-sapwood border is detected, to separate logs with a high knot detection rate from those with a low detection rate. In that way, a decision can be made whether or not to trust the knot models obtained from CT scanning. This can potentially aid both sawmills and researchers working with log models based on CT. La tomographie aux rayons X assistée par ordinateur (TO) des billes offre la possibilité d'optimiser le débitage dans les scieries. Cela repose sur la précision avec laquelle les nœuds sont détectés pour évaluer la qualité interne. Cependant, lorsque les billes sont entreposées, elles sèchent jusqu'à un certain point et cela influence la variation de la densité dans les billes, et par conséquent les images radiologiques. Pour cette raison, il est hypothétiquement difficile de détecter les caractéristiques dans les billes partiellement séchées à l'aide de la TO. Cet article étudie l'effet de l'erreur de détection de la limite entre le bois de cœur et le bois d'aubier, potentiellement attribuable au séchage partiel, sur la détection des nœuds dans des billes de pin gris ( Pinus banksiana Lamb.) et d'épinette blanche ( Picea glauca (Moench) Voss) provenant du Nouveau-Brunswick, au Canada. Un algorithme de détection automatisée des nœuds a été comparé à des mesures de référence de nœuds effectuées manuellement. Les résultats ont montré que la forme du bois de cœur qui est détectée influence la détection des nœuds. Il a également été démontré que les billes peuvent être réparties en deux groupes sur la base de la justesse de la détection de la limite entre le bois de cœur et le bois d'aubier, ce qui permet de séparer les billes chez lesquelles le taux de détection des nœuds est élevé de celles chez lesquelles le taux de détection des nœuds est faible. De cette façon, on peut prendre la décision de faire confiance ou non aux nœuds modélisés obtenus avec le balayage par TO. Cela peut possiblement aider tant les scieries que chercheurs qui utilisent la modélisation des billes fondée sur la TO Validerad;2017;Nivå 2;2017-07-03 (andbra)

Some ideas of neuro-dynamic programming (NDP) are illustrated by considering the problem of optimally managing a forest stand under uncertainty. Because reasonable growth models require state information such as height (or age), basal area, and stand diameter, as well as an indicator variable for treatments that have been performed on the stand, they can easily lead to very large state spaces that include continuous variables. Realistic stand management policies include silvicultural options such as pre-commercial and commercial thinning as well as post-harvest treatments. We are interested in problems that are stochastic in their basic growth dynamics, in market prices, and in disturbances, ranging from insects to fire to hurricanes. NDP algorithms are appropriate for problems with large dimensions that may lack a simple model of dynamics and stochastic processes. This paper looks at applying these ideas in the context of a multispecies model. Results show that policies obtained using NDP are optimal within a 95% confidence interval or better. The set of states and controls incorporated into our NDP model allows us to develop optimal policies with a level of detail not typically seen in the forestry literature.

The ability to distinguish peatland types at the landscape scale has implications for inventory, conservation, estimation of carbon storage, fuel loading, and postfire carbon emissions, among others. This paper presents a multisensor, multiseason remote sensing approach to delineate boreal peatland types (wooded bog, open fen, shrubby fen, treed fen) using a combination of multiple dates of L-band (24 cm) synthetic aperture radar (SAR) from ALOS PALSAR, C-band (∼5.6 cm) from ERS-1 or ERS-2, and Landsat 5 TM optical remote sensing data. Imagery was first evaluated over a small test area of boreal Alberta, Canada, to determine the feasibility of using multisensor SAR and optical data to discriminate peatland types. Then object-based and (or) machine-learning classification algorithms were applied to 3.4 million ha of peatland-rich subregions of Alberta, Canada, and the 4.24 million ha region of Michigan’s Upper Peninsula where peatlands are less dominant. Accuracy assessments based on field-sampled sites show high overall map accuracies (93%–94% for Alberta and Michigan), which exceed those of previous mapping efforts.

This paper presents a model for optimizing the management of single-species, even-aged stands. The model comprises a number of state variables, given by functions initially differentiable with respect to time, which cease to be due to the discontinuities that cause instant silvicultural treatments. Nevertheless, the proposed model maintains its differentiability with respect to the decision variables (timing, type, and intensity of each thinning, and rotation age). This allows for formulation of the problem of optimal management of this type of stands as a linearly constrained smooth optimization problem, which can be efficiently solved by any derivative-based optimization method. The effectiveness of this formulation is shown by using a sequential quadratic programming (SQP) algorithm to design the optimal management of Pinus pinaster Ait. in Asturias (northwestern Spain) from an economic perspective. These results are compared with those obtained using two methods that do not require derivatives. The SQP, as representative of gradient-type methods, proved robust and much more efficient than the derivative-free methods.

This paper presents a simulation-based analysis of a multiple-round timber combinatorial auction in the timber industry. Currently, most timber auctions are single-unit auctions (i.e., each forest stand is sold separately). However, other types of auctions could be applied to take advantage of the various needs of the bidders with respect to species, volumes, and quality. This study aims to analyze the use of combinatorial auction to this specific context using a simulation approach. Various number of auctions per year, periodicity, lot size, and number of bidders are considered as parameters to set up the different market configurations. The outcomes of both combinatorial auction and single-unit auction are compared with respect to different setup configurations. This analysis shows that combinatorial auction can bring more profit for both seller and buyer when the market is less competitive.

This paper explores the ecosystem services associated with woodlands, as they are viewed by individuals in Scotland, with the idea to reconcile objectives for multifunctionality with the legacy of past forestry systems that were not designed with multifunctionality in mind. Research follows a semi-qualitative route and applies the Q method to identify and explain a range of attitudes among the general public and forestry-associated stakeholders regarding the functional future of forestry in Scotland. Four distinctive groups of attitudes were identified and key factors influencing the attitudinal diversity were explained. Despite the uncovered attitudinal heterogeneity, all groups of attitudes have strong emphasis on native woodland regeneration and on improvement of aesthetic values of woodlands but differ concerning afforestation. An improved understanding of what people think provided an indication of their recognition of ecosystem services types and the trade-offs between these, opportunities available, and factors that can hamper forestry development (e.g., concerning the aspiration of increasing Scotland’s forest cover to 25%). Findings suggest that the productivists’ position (for which the economic objectives are important) remains strong in Scotland. Results (compared with those in several other countries) demonstrate comparability between public and stakeholder perspectives in support of the multifunctional forestry, and this has distinct policy relevance and implications for decision-making.

Mixed-species stands are on the advance in Europe. They fulfil many functions better than monocultures. Recent papers show that mixed stands can have higher yields, but it remains open whether mixed stands simply grow faster along the same self-thinning lines as pure stands or have higher maximum stand densities. We analyzed the effect of species mixing on maximum density based on triplets of pure and mixed stands at approximately maximum density. Most considered mixtures include Norway spruce (Picea abies (L.) H. Karst.). We show that (i) in mixed stands, maximum density is, on average, 16.5% higher than in neighbouring pure stands, and (ii) species mixtures with Norway spruce exceed densities of pure stands by 8.8%, on average. For individual species mixtures, we find a significant density effect of +29.1% for Norway spruce mixed with European larch (Larix decidua Mill.) and +35.9% for Scots pine (Pinus sylvestris L.) in association with European beech (Fagus sylvatica L.). No significant links with stand variables such as age and mean tree size and site fertility were found. The results indicate that species mixing substantially increases stand density, indicating a higher carrying capacity caused by a higher supply and use efficiency of resources. The implications for inventory, silviculture, and forest modelling are discussed.

This paper investigates the practices of the value-added wood products industry in British Columbia (BC) with respect to innovativeness using the results of an online survey. The survey employed an indirect self-evaluation scale to assess the propensity to create and (or) adopt new products, processes, and business systems. Using chain of custody certification as an example of business systems innovation, this study also investigated the attitudes of the value-added wood products manufacturers, who were already certified or who may become certified, towards innovation in this form. Results show that the respondents rated themselves as more innovative with respect to business systems innovation compared with product and process innovations. Overall, innovation levels were low in the BC value-added wood products sector, a result which was confirmed in the case of chain of custody certification.

Growing demand for bioenergy, biofuels, and bioproducts has increased interests in the utilization of biomass residues from forest treatments as feedstock. In areas with limited history of industrial biomass utilization, uncertainties in the quantity, distribution, and cost of biomass production and logistics can hinder the development of new bio-based industries. This paper introduces a new methodology to quantify and spatially describe delivered feedstock volumes and costs across landscapes of arbitrary size in ways that characterize operational and annual management decision-making. Using National Agricultural Imagery Program (NAIP) imagery, the forest is segmented into operational-level treatment units. A remote sensing model based on NAIP imagery and Forest Inventory and Analysis plot data are used to attribute treatment units with stand-level estimates of basal area, tree density, aboveground biomass, and quadratic mean diameter. These methods are applied to a study site in southwestern Colorado to assess the quantity and distribution of treatment residue for use in bioenergy production. Results from the case study demonstrate how this generalized approach can be used in the analysis and decision-making process when establishing new bioenergy industries that use forest residue as feedstock.

The choice of a baseline against which to evaluate changes in carbon stocks is a critical component of any forest carbon offset market. In this paper, we use a discrete dynamic programming model and data from a lodgepole pine (Pinus contorta Douglas ex Loudon) stand in northeastern British Columbia, Canada, to demonstrate that different baselines have little or no effect on optimal harvest decision but can have a large impact on economic returns to a landowner. The results reveal that the magnitude of the financial return to the landowner is dependent on the starting conditions of both the predetermined baseline and the proposed carbon offset project. The study also shows that when given the choice between alternative baselines, a landowner will always choose a fixed baseline over a business-as-usual baseline.

Developing a plan of action for the future use of forest resources requires a way to predict the development of the forest through time. These predictions require the use of inventory data and growth models that contain a large number of uncertainties. These uncertainties impact the quality of the predictions, and if not accounted for, they can lead to the selection of a suboptimal management plan. To account for and manage the uncertainties and associated risk, we have explored the use of stochastic programming. Stochastic programming can integrate uncertainty into the optimization process by solving the problem for a large number of potential scenarios of the forests future development. The selection of an appropriately sized set of scenarios involves a trade-off between tractability issues and problem representation issues. In this paper, an analysis of the trade-offs is conducted. Two cases are studied, one in which only the uncertainty of the inventory data is included and a second in which both growth model and inventory data uncertainties are included. The impact of increasing the number of scenarios on the problem representation is examined through a simple even-flow problem.

The United States (US) Lacey Act 2008 amendment (LAA) is a timber legality regulation that requires US importers to monitor and minimize the risk of illegally harvested wood products within their supply chains. This paper empirically examines the effect of the LAA on Chinese companies’ export costs to the US. The study uses 138 responses from two surveys in Shanghai, China, in 2013, i.e., 5 years after the LAA was implemented. Given the high proportion of zero export increase indicated by the Chinese companies, a zero-inflated ordered probit model was used to model Chinese companies’ export cost increases to the US. The research results demonstrate that pre-LAA raw material sourcing patterns are primary indicators of the respondents’ export cost increase to the US as a result of the LAA. From the results, it can be inferred that log and lumber importers from suspect regions are taking additional measures, by changing their procurement practices, to ensure the legality of their raw material, which is adding to their cost structure. The results also indicate that smaller companies, given their flexibility with raw material procurement, were less likely to experience a post-LAA cost increase relative to their larger counterparts.

Mexican temperate forests, at the southernmost end of the distribution range of this ecosystem, are the world’s centre of diversity of pine and oak, with 55 and 161 species, respectively. Such forests are threatened by land-use change, unsustainable forest management practices, and climate change; these threats reduce their diversity, alter the distribution ranges of species, modify disturbance regimes, and reduce ecosystem adaptability. This paper briefly reviews (i) the ecology of the Mexican temperate forests, (ii) the ecological basis for the unique diversity of pine and oak species, (iii) the main disturbances as well as the main drivers of global changes affecting these forests, in particular climate change, and (iv) the social, economic, and cultural factors to be considered in proposing a new forest management approach. It proposes a new conceptual framework to manage Mexican temperate forests that are in line with (i) their natural dynamics, (ii) the rapidly changing and uncertain global environmental, social, and economic conditions, and (iii) the complex adaptive system approach. This new forest management combines functional zoning, multispecies plantations, and sylvicultural interventions to increase the adaptive capacity of forests as a way to balance the increasing need for timber products with the need for other ecosystem services facing rapidly changing and uncertain future environmental, social, and economic conditions.

The mountain pine beetle, Dendroctonus ponderosae Hopkins (Coleoptera, Curculionidae), a native insect of North America, periodically reaches population sizes that cause serious economic impact to the forest industry in western North America. The most recent outbreak in British Columbia (BC), Canada, which began in the late 1990s, is only now (2015) abating, after causing unprecedented tree mortality in lodgepole pine (Pinus contorta Douglas ex. Loudon) forests. In this paper, we make use of permanent research plots to report on the condition of lodgepole pine forests in the Chilcotin Plateau of central BC, which underwent two fully documented mountain pine beetle outbreaks. In this region, the first outbreak started in the late 1970s and lasted until the mid-1980s; the second outbreak began in the early 2000s and ended in 2010. We measured the impacts of these outbreaks in terms of tree mortality and describe the characteristics of the legacies that remain following these outbreaks, including survivors in various canopy layers and levels of existing and new regeneration. We provide evidence in support of the existence of postdisturbance legacies that classify into five distinct stand structure types. Abundant regeneration and surviving intermediate canopy layers in most stands indicate that management actions to restock pine stands in this area will not likely be necessary. The information provided by this study is important for estimating future forest development and timber supply and for forest planning and management.

Incident management teams (IMTs) are responsible for managing the response to wildfires. One of the objectives of IMTs is the protection of assets and infrastructure. In this paper, we develop a mathematical model to assist IMTs in assigning resources to asset protection activities during wildfires. We present a mixed integer programming model for resource allocation with the aim of protecting the maximum possible total value of assets. The model allows for mixed vehicle types with interchangeable capabilities and with travel times determined by vehicle-specific speed and road network information. We define location-specific protection requirements in terms of vehicle capabilities. The formulated model extends classic variants of the team orienteering problem with time windows. The model capabilities are demonstrated using a hypothetical fire scenario impacting South Hobart, Tasmania, Australia. Computational testing shows that realistically sized problems can be solved within a reasonable time.

There is a growing demand for improving the measurement of forest resources, with more frequent updating and better information on environmental variables. We explore the cost efficiency of a stratified two-stage design using area sampling to estimate the forest plantation and native forest areas in southern Chile. Analytical expressions for the approximate mean square error of combined and separate ratio estimators are derived applying Taylor linearization. Under a unified framework, this procedure allows the evaluation of the precision of design and post-design estimators for unequal unit area sizes at both stages. Monte Carlo simulations were used to assess empirically the approximate analytical measures of the mean square error and the biases associated with the ratio estimators. Adopting proportional allocation among strata and clusters, the optimal allocation among the two stages is determined. A substantial improvement in sampling precision was achieved using the separate ratio estimator and the bias was found to be small. Post-stratification based on categorical information on growing zones also improved the precision of estimating the forest plantation area and a smaller extent the native forest area. The results of this paper support a wider adoption of sampling methods to estimate land use and land cover at regional or national levels.

Universal kriging gives the optimal linear model to incorporate auxiliary information in data analysis in the presence of spatial dependence of observations if the underlying variogram is known. However, in practice, the variogram is typically unknown and its estimation constitutes one of the major problems in universal kriging theory. In this paper, a new method is proposed to estimate the variogram and the mean function in universal kriging based on the relationship between the second moments of the variable Z(s) and the auxiliary variables. The performance of the proposed method is analysed in three case studies: the prediction of site index in an Italian stone pine ( Pinus pinea L.) forest, the estimation of growing stock in a Scots pine ( Pinus sylvestris L.) stand, and the assessment of the environmental factors involved in the distribution of a Meliosma species in a tropical montane cloud forest. The results show that the proposed method performs as well as the maximum likelihood and least squares methods in terms of unbiasedness and precision of the kriging predictor and prediction error variance estimation. The proposed method allows the spatial variability linked to environmental and geographical factors to be identified in the analysis of data from forest ecosystems.

Single-tree selection has been employed widely in northern Japanese mixed forests, but management-induced changes in forests are not well understood. This study examined demographic parameters of major tree species during a 20-year study of a 68 ha stand in which single-tree selection has been conducted since 1971. Results showed that growth and survival of conifers (mostly Abies sachalinensis (Fr. Schm.) Masters) was the most strongly positively affected by the treatment. Nevertheless, recruitment of conifers was not sufficiently improved, suggesting their decreased dominance over the longer term. Instead, shade-intolerant broad-leaved species (mainly Betula ermanii Cham.) will gradually increase because of their higher recruitment rates after the treatment. Shade-tolerant broad-leaved species (mainly Acer mono Maxim. and Tilia japonica (Miq.) Simonkai) appeared to experience the most distinct negative effects, especially on survival. These trends differed markedly from those reported in previous papers concerning partial harvesting systems, which predicted an increase in dominance of shade-tolerant species. The results shown here should be generalized carefully because we have investigated only one stand without repetition of the control area. Nevertheless, trends described in this large-scale, long-term study could provide a basis for simulating stand dynamics. We discussed possible reasons for the observed patterns and provided implications for sustainable management in the region.