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Insect outbreaks are major drivers of natural disturbances in forest ecosystems. Outbreaks can have both direct and indirect effects on the composition of soil arthropod communities through canopy opening, nutrient addition and predator-prey interactions. In this study, we aimed to understand the effects of forest tent caterpillar (Malacosoma disstria; FTC) outbreaks through cascading effects on ant communities in both temperate and boreal forests in Canada. Pitfall traps and Berlese funnels were used to compare the ant communities, as well as the surrounding arthropod communities, between control and outbreak sites in boreal and temperate forests (in Quebec, Canada). Using the Sørensen dissimilarity index, we determined the alpha and beta diversity of the ant community. Other arthropods collected in the traps were counted to evaluate the richness and abundance of potential prey for the ants and other potential predators of the FTC. We used an indicator species analysis to examine the species associated with sites defoliated by the outbreak. In the boreal forest, we found that FTC outbreaks caused decreases in species richness and increases in the evenness of ant communities in defoliated sites. In the boreal forest sites, species composition varied significantly between control and outbreak sites. This pattern was driven in part by the presence of other predators. A similar, but weaker pattern was observed in the temperate forest. We saw no changes in the beta diversity in the boreal forest, but did see a significant decrease in the temperate forest between the outbreak sites and the control sites. Ant species in the boreal forest tended to exhibit a more marked preference for either control or previously defoliated sites than species in the temperate forest. Our study showed that disturbances such as insect outbreaks can drive changes in the ant community. While we saw small effects of outbreaks, manipulation experiments using resource addition could help us validate the mechanisms behind these relationships.

Current ecological models predict profound climate change-related effects on the natural disturbance regimes of forests. Spruce budworm (Choristoneura fumiferana) (SBW) is the principal insect defoliator in eastern North America, and SBW outbreaks have a major impact on the structure and function of the Canadian boreal forest, as defoliation leads to decreased tree growth, increased mortality, and lower forest productivity. SBW outbreaks have become more severe over the last century with the changing climate; however, little is known about how the integrated effect of climate and SBW alters the growth of host species. Here we evaluate how climate and outbreak severity combined to affect black spruce (Picea mariana) growth during the SBW outbreak that occurred between 1968-1988 and 2006-2017. We compiled dendrochronological series (2271 trees), outbreak severity (estimated by observed aerial defoliation), and climate data for 164 sites in Québec, Canada. We used a linear mixed effect model to determine the impacts of climatic parameters, cumulative defoliation (of the previous five years), and their interaction effect on basal area growth. At maximum outbreak severity, basal area growth of black spruce was reduced by 14%–18% over five years due to SBW effect. This outbreak growth response was affected by climate: warmer previous summer minimum temperatures and a higher previous summer climate moisture index (CMI) further decreased growth by 11% and 4%, respectively. In contrast, the negative effect of defoliation was attenuated by 9% for a warmer minimum temperature in the previous spring and 7% for a warmer maximum temperature in the previous summer. This study improves our understanding of combined insect–climate effects on growth and helps in the predictions of future SBW-related damage to forest stands to bolster sustainable forest management. We also recommend that projections of boreal forest ecosystems include several classes of SBW defoliation severity coupled with multiple climatic scenarios.

Clear-cutting has been the dominant harvesting method used in boreal forest silviculture. Reducing the potential negative effects of intensive forestry activities on ecosystems, e.g., the simplification and homogenization of stand structure, requires diversifying silvicultural practices to promote forest resilience in the face of climate change. Priority therefore lies in developing, evaluating, and adapting partial cutting as a potential silvicultural option for ensuring the sustainable management of boreal forests. In this chapter, we summarize the findings of two large-scale experiments conducted in Canadian boreal forests that tested new silvicultural approaches and explore their implications for forest management. We discuss the effects of these treatments on tree growth, tree mortality, regeneration, and biodiversity, and we examine the challenges of existing silvicultural approaches in the context of climate change.

Long-term disturbance histories, reconstructed using diverse paleoecological tools, provide high-quality information about pre-observational periods. These data offer a portrait of past environmental variability for understanding the long-term patterns in climate and disturbance regimes and the forest ecosystem response to these changes. Paleoenvironmental records also provide a longer-term context against which current anthropogenic-related environmental changes can be evaluated. Records of the long-term interactions between disturbances, vegetation, and climate help guide forest management practices that aim to mirror “natural” disturbance regimes. In this chapter, we outline how paleoecologists obtain these long-term data sets and extract paleoenvironmental information from a range of sources. We demonstrate how the reconstruction of key disturbances in the boreal forest, such as fire and insect outbreaks, provides critical long-term views of disturbance-climate-vegetation interactions. Recent developments of novel proxies are highlighted to illustrate advances in reconstructing millennial-scale disturbance-related dynamics and how this new information benefits the sustainable management of boreal forests in a rapidly changing climate.

Uncertainty surrounding global change impacts on future forest conditions has motivated the development of silviculture strategies and frameworks focused on enhancing potential adaptation to changing climate and disturbance regimes. This includes applying current silvicultural practices, such as thinning and mixed-species and multicohort systems, and novel experimental approaches, including the deployment of future-adapted species and genotypes, to make forests more resilient to future changes. In this chapter, we summarize the general paradigms and approaches associated with adaptation silviculture along a gradient of strategies ranging from resistance to transition. We describe how these concepts have been operationalized and present potential landscape-scale frameworks for allocating different adaptation intensities as part of functionally complex networks in the face of climate change.

The increasing effects of climate and global change oblige ecosystem-based management to adapt forestry practices to deal with uncertainties. Here we provide an overview to identify the challenges facing the boreal forest under projected future change, including altered natural disturbance regimes, biodiversity loss, increased forest fragmentation, the rapid loss of old-growth forests, and the need to develop novel silvicultural approaches. We specifically address subjects previously lacking from the ecosystem-based management framework, e.g., Indigenous communities, social concerns, ecological restoration, and impacts on aquatic ecosystems. We conclude by providing recommendations for ensuring the successful long-term management of the boreal biome facing climate change.

Understanding structurally complex boreal stands is crucial for designing ecosystem management strategies that promote forest resilience under global change. However, current management practices lead to the homogenization and simplification of forest structures in the boreal biome. In this chapter, we illustrate two options for managing productive and resilient forests: (1) the managing of two-aged mixed-species forests; and (2) the managing of multi-aged, structurally complex stands. Results demonstrate that multi-aged and mixed stand management are powerful silvicultural tools to promote the resilience of boreal forests under global change.

Ecosystem-based forest management associated with partial harvesting (PH) is intended to balance ecological and economic values of sustainable forest management. The potential for delayed growth response and elevated mortality of advance regeneration following PH remains a critical concern, and may present a barrier to more widespread implementation of this approach. We used 835 permanent continuous forest inventory plots to examine the rate and time course of species-specific regeneration growth and mortality of eight tree species in the first fifteen years following operational partial harvests in the mixed-species forests of Maine, United States. We aimed to provide a quantitative understanding on how regeneration of different species responded to PH in terms of growth and mortality. In addition, we evaluated how the patterns and magnitudes of growth and mortality responses developed over time, if these responses occur gradually or suddenly, and if the patterns of the responses were persistent. We found that the response magnitude, temporal trajectories of responses, and the length of initial lag-period largely varied across species, PH treatments, and the variables examined. For sapling diameter growth, paper birch (Betula papyrifera Marshall) and red maple (Acer rubrum L.) showed immediate responses to high-intensity PH, while a five-year lag-period was observed in balsam fir (Abies balsamea (L.) Mill.), American beech (Fagus grandifolia Ehrh.), red spruce (Picea rubens Sarg.) and eastern hemlock (Tsuga canadensis (L.) Carri`ere) and a 10-year lag period in northern white-cedar (Thuja occidentalis L.). The initial increase in sapling mortality was observed in balsam fir, American beech, red maple and northern white-cedar, but not in other species. Sapling survival reached a stable state irrespective of species after the initial five-years following harvests. In partially harvested stands, identifying preharvest conditions related to postharvest density, growth, and mortality was complex and interacted with time since harvest. Our results suggest that broad application of PH only results in species-specific gains, losses, and delays in regeneration responses within mixed-species stands. Future research should consider PH in combination with other treatments to initiate immediate responses to a wider range of species., We thank to US Forest Service Forest Inventory and Analysis (FIA) for access to the long-term database. Funding was provided by the United States National ScienceFoundation’s Center for Advanced Forestry Systems (#1915078) and R-II Track-2 FEC (#1920908) and from NSRC Alliance (ALLRP 557166 - 20).

Purpose of Review Carbon sequestration and storage in forest ecosystems is often promoted as a solution for reducing CO2 concentrations in the atmosphere. Yet, our understanding is lacking regarding how forest management strategies affect the net removal of greenhouse gases and contribute to climate change mitigation. Here, we present a review of carbon sequestration and stock dynamics, following three strategies that are widely used in boreal, temperate and tropical forests: extensive forest management, intensive forest management and old-growth forest conservation. Recent Findings Several studies show that specific forest management strategies can improve carbon sequestration capacity and soil carbon storage. Within these studies, the old-growth forest conservation strategy results in greater carbon storage in soils than do extensive and intensive forest management. Intensive forest management enhances forest carbon sequestration capacity through afforestation using fast-growing species, mechanical soil preparation from low to moderate intensity and N fertilization. Extensive forest management is an intermediate compromise regarding carbon sequestration and soil carbon storage, between conservation and intensive forest management strategies. With respect to silvicultural treatments, partial cutting is a practice that increases forest carbon sequestration rates and maintains higher carbon storage in soils compared to clear-cuts. Each silvicultural practice that is discussed in this review showed a similar effect on forest carbon in all biomes, although the magnitude of these effects differs mainly in terms of heterotrophic respiration. Summary To achieve sustainable management and fulfill industrial demand and profitability, specific gaps must be dealt with to improve our scientific knowledge regarding forest carbon sequestration in a climate change context, mainly through the integration of the three aforementioned strategies in a functional zoning approach at the landscape scale. We present a review with promising strategies for guiding sustainable forest management in such a global context.

Changing climates are altering the structural and functional components of forest ecosystems at an unprecedented rate. Simultaneously, we are seeing a diversification of public expectations on the broader sustainable use of forest resources beyond timber production. As a result, the science and art of silviculture needs to adapt to these changing realities. In this piece, we argue that silviculturists are gradually shifting from the application of empirically derived silvicultural scenarios to new sets of approaches, methods and practices, a process that calls for broadening our conception of silviculture as a scientific discipline. We propose a holistic view of silviculture revolving around three key themes: observe, anticipate and adapt. In observe, we present how recent advances in remote sensing now enable silviculturists to observe forest structural, compositional and functional attributes in near-real-time, which in turn facilitates the deployment of efficient, targeted silvicultural measures in practice that are adapted to rapidly changing constraints. In anticipate, we highlight the importance of developing state-of-the-art models designed to take into account the effects of changing environmental conditions on forest growth and dynamics. In adapt, we discuss the need to provide spatially explicit guidance for the implementation of adaptive silvicultural actions that are efficient, cost-effective and socially acceptable. We conclude by presenting key steps towards the development of new tools and practical knowledge that will ensure meeting societal demands in rapidly changing environmental conditions. We classify these actions into three main categories: re-examining existing silvicultural trials to identify key stand attributes associated with the resistance and resilience of forests to multiple stressors, developing technological workflows and infrastructures to allow for continuous forest inventory updating frameworks, and implementing bold, innovative silvicultural trials in consultation with the relevant communities where a range of adaptive silvicultural strategies are tested. In this holistic perspective, silviculture can be defined as the science of observing forest condition and anticipating its development to apply tending and regeneration treatments adapted to a multiplicity of desired outcomes in rapidly changing realities.

The esophagus is the centerpiece of the digestive system of individuals and plays an essential role in transporting swallowed nutrients to the stomach. Diseases of the esophagus can alter this mechanism either by causing anatomical damage that obstructs the lumen of the organ (e.g., peptic, or eosinophilic stricture) or by generating severe motility disorders that impair the progression of the alimentary bolus (e.g., severe dysphagia of neurological origin or achalasia). In all cases, nutrient assimilation may be compromised. In some cases (e.g., ingestion of corrosive agents), a hypercatabolic state is generated, which increases resting energy expenditure. This manuscript reviews current clinical guidelines on the dietary and nutritional management of esophageal disorders such as severe oropharyngeal dysphagia, achalasia, eosinophilic esophagitis, lesions by caustics, and gastroesophageal reflux disease and its complications (Barrett’s esophagus and adenocarcinoma). The importance of nutritional support in improving outcomes is also highlighted.

Sapwood characteristics, such as sapwood area as well as thermal and hydraulic conductivity, are linked to species-specific hydraulic function and resource allocation to water transport tissues (xylem). These characteristics are often unknown and thus a major source of uncertainty in sap flow data processing and transpiration estimates because bulk rather than species-specific values are usually applied. Here, we analyzed the sapwood characteristics of fifteen common tree species in eastern North America from different taxa (i.e., angiosperms and gymnosperms) and xylem porosity groups (i.e., tracheid-bearing, diffuse- or ring-porous species). We quantified their sapwood area changes with stem diameter (allometric scaling) and thermal conductivity. We combined these measurements with species-specific values of wood density and hydraulic conductivity found in literature and assessed the role of wood anatomy in orchestrating their covariation. Angiosperms (ring- and diffuse-porous species), with specialized vessels for water transport, showed steeper relation (scaling) between tree size and sapwood area in comparison to gymnosperms (tracheid-bearing species). Despite the variability in thermal conductivity between species, gymnosperms (angiosperms) were characterized by lower (higher) wood density and higher (lower) sapwood moisture content, resulting in non-significant differences in sapwood thermal conductivity between taxa and xylem porosity groups. Clustering of species sapwood characteristics based on taxa or xylem porosity could facilitate more accurate parameterizations of these attributes. When combined with an increasing number of sap flow observations, these findings can improve tree- and landscape-level transpiration estimates, leading to more robust partitioning of terrestrial water fluxes.

Background Pouchitis and other inflammatory disorders of the pouch (IDP), such as Crohn′s-like disease of the pouch (CDP), are frequent in patients operated for a previous diagnosis of ulcerative colitis. Many different therapies have been used, but the effectiveness of immunosupresants (IMM) has been poorly explored in this setting. Our aim was to evaluate the use, efficacy and safety of IMM in patients with pouchitis or another IDP. Methods Retrospective and multicentric study of a Spanish cohort of pouch-carrying patients with previous diagnosis of ulcerative colitis, and subsequent diagnosis of IDP, following ECCO diagnostic criteria. Patients who used IMM to treat these conditions were selected. Clinical effectiveness was evaluated at long-term. We defined clinical remission as returning to the previous stool frequency, no pain or defecatory urgency, clinical response as the improvement in these parameters without the achievement of remission, and non-response as no improvement or worsening symptoms. Endoscopic response was evaluated when possible using modified pouchitis disease activity index (PDAI) endoscopic subscore. Adverse events were collected. We used descriptive statistics. Results In the overall cohort of 338 patients with IDP, 93 (27%) were treated with IMM. Of those, 57% males, median age 40 (20-71) ys, and 72% non-smokers. Colectomy was performed at a median age of 31 (18-63) ys and IPD was diagnosed 25 (1-235) months after ileostomy closure. IMM used were thiopurines (n=86), methotrexate (n=4), cyclosporine (n=2) and tacrolimus (n=1). IMM were used as monotherapy in 66 (71%) cases and were indicated as treatment of pouchitis (n=60, 65%), CDP (n=32, 34.4%) and cuffitis (n=1, 1%). Effectiveness was evaluated only for thiopurine monotherapy (n=62). After a median follow-up of 23 (1-234) months, clinical remission was achieved in 31%, clinical response in 31% and non-response in 38% (Figure 1). There were no differences in effectiveness between pouchitis and CDP (63.9% vs 57.7%, p= 0.62). Endoscopic response was evaluated in 19 (30.6%) cases. After a median of 9 months of follow-up median PDAI endoscopic subscore dropped from 3 (range 2-4) to 1 (range 0-3), (Figure 2). Adverse events related with treatment appeared in 28 patients (45%). Thiopurines were discontinued in 39 cases (63%) due to failure (17), toxicity (16) and long remission (6 cases). Conclusion In our cohort, thiopurines were used in 27% of patients with IDP, with long-term benefit (remission or response) in around two-thirds of them. This therapy could be one more option to manage these disorders.

Background Pouchitis and Crohn′s-like disease of the pouch (CDP) can be refractory to conventional therapy. Evidence of biological therapy has been rarely reported in large patient cohorts. We explored the use and effectiveness of these therapies and compared the success of a second biologic after antiTNF failure. Methods This is a retrospective RESERVO study of the Spanish cohort of GETECCU, that included patients operated for ulcerative colitis, with pouch construction, and subsequent diagnosis of pouchitis, CDP or cuffitis second ECCO diagnostic criteria1. Patients treated with antiTNF, Vedolizumab and/or Ustekinumab were selected. Clinical effectiveness was evaluated at long-term. We defined clinical remission as returning to the previous stool frequency, no pain or defecatory urgency, clinical response as the improvement in these parameters without the achievement of remission and non-response as no change or worsening of these symptoms. We also compared the effectiveness of second biologic (antiTNF vs vedolizumab-ustekinumab) after antiTNF failure, using descriptive and comparative statistics. Results The cohort comprised 145 patients. Demographic and clinical characteristics are represented in Table 1. A total of 232 biologic therapies were indicated. Of the total cohort, 60 (41.3%), 21 (14.4%) and 6 (4.1%) used two, three and four lines, respectively. Biologics used were Infliximab (n=95), Adalimumab (n=69), Vedolizumab (n=35), Ustekinumab (n=26) and Golimumab (n=7). Therapy characteristics, clinical effectiveness, need for intensification, discontinuation, and therapy duration for each biological therapy are represented in Table 2. Global rates of clinical remission, response, non-response and loss of response to a first biologic were 21.8%, 27.5%, 21.1% and 29.6%. Female gender was the only factor associated with effectiveness to a first biologic in univariate analysis (OR 2.16, CI 1.08–4.32, p 0.027). There were no significant differences regarding efectiveness between type of pouch disorder (pouchitis vs CDP, 51.6 vs 47.6%, p 0.48) or biologic agents. Thirty-nine patients received a second biologic after prior antiTNF failure (28 a second antiTNF and 11 non-antiTNF: 6 Vedolizumab, 5 Ustekinumab). Basal characteristics in this subgroup showed no significant differences. Clinical response (21.4 vs 63.6%, p 0.02) and discontinuation therapy rates (82.2 vs 54.5 %, p 0.04) after 11 months showed a more favorable profile for non-antiTNF therapy. Conclusion Biologics represent an effective option in the management of pouchitis and Crohn′s like disease of the pouch. Despite our small sample size, non-antiTNF therapy could be the best option after antiTNF failure. 1Fernando Magro. J Crohns Colitis 2017; 11(6): 649–670.

Changing climates are altering the structural and functional components of forest ecosystems at an unprecedented rate. Simultaneously, we are seeing a diversification of public expectations on the broader sustainable use of forest resources beyond timber production. As a result, the science and art of silviculture needs to adapt to these changing realities. In this piece, we argue that silviculturists are gradually shifting from the application of empirically derived silvicultural scenarios to new sets of approaches, methods and practices, a process that calls for broadening our conception of silviculture as a scientific discipline. We propose a holistic view of silviculture revolving around three key themes: observe, anticipate and adapt. In observe, we present how recent advances in remote sensing now enable silviculturists to observe forest structural, compositional and functional attributes in near-real-time, which in turn facilitates the deployment of efficient, targeted silvicultural measures in practice that are adapted to rapidly changing constraints. In anticipate, we highlight the importance of developing state-of-the-art models designed to take into account the effects of changing environmental conditions on forest growth and dynamics. In adapt, we discuss the need to provide spatially explicit guidance for the implementation of adaptive silvicultural actions that are efficient, cost-effective and socially acceptable. We conclude by presenting key steps towards the development of new tools and practical knowledge that will ensure meeting societal demands in rapidly changing environmental conditions. We classify these actions into three main categories: re-examining existing silvicultural trials to identify key stand attributes associated with the resistance and resilience of forests to multiple stressors, developing technological workflows and infrastructures to allow for continuous forest inventory updating frameworks, and implementing bold, innovative silvicultural trials in consultation with the relevant communities where a range of adaptive silvicultural strategies are tested. In this holistic perspective, silviculture can be defined as the science of observing forest condition and anticipating its development to apply tending and regeneration treatments adapted to a multiplicity of desired outcomes in rapidly changing realities.

Introduction: the ESPEN guideline offers a multidisciplinary focus on clinical nutrition in inflammatory bowel disease (IBD). Methodology: the guideline is based on a extensive systematic review of the literature, but relies on expert opinion when objective data are lacking or inconclusive. The conclusions and 64 recommendations have been subject to full peer review and a Delphi process, in which uniformly positive responses (agree or strongly agree) were required. Results: IBD is increasingly common and potential dietary factors in its etiology are briefly reviewed. Malnutrition is highly prevalent in IBD - especially in Crohn's disease. Increased energy and protein requirements are observed in some patients. The management of malnutrition in IBD is considered within the general context of support for malnourished patients. Treatment of iron deficiency (parenterally, if necessary) is strongly recommended. Routine provision of a special diet in IBD is not, however, supported. Parenteral nutrition is indicated only when enteral nutrition has failed or is impossible. The recommended perioperative management of patients with IBD undergoing surgery accords with general ESPEN guidance for patients having abdominal surgery. Probiotics may be helpful in UC but not in Crohn's disease. Primary therapy using nutrition to treat IBD is not supported in ulcerative colitis but is moderately well supported in Crohn's disease, especially in children, where the adverse consequences of steroid therapy are proportionally greater. However, exclusion diets are generally not recommended and there is little evidence to support any particular formula feed when nutritional regimens are constructed. Conclusions: available objective data to guide nutritional support and primary nutritional therapy in IBD are presented as 64 recommendations, of which 9 are very strong recommendations (grade A), 22 are strong recommendations (grade B), and 12 are based only on sparse evidence (grade 0); 21 recommendations are good practice points (GPP).Introducción: la guía ESPEN ofrece un enfoque multidisciplinar de la nutrición clínica en la enfermedad inflamatoria intestinal (EII). Metodología: la guía se basa en una extensa revisión sistemática de la literatura y en la opinión de expertos cuando faltan datos objetivos o estos no son concluyentes. Las conclusiones y las 64 recomendaciones han sido objeto de una revisión completa por pares y de un proceso Delphi en el que se requerían respuestas fuertemente positivas (de acuerdo o totalmente de acuerdo). Resultados: la EII es cada vez más común y se revisan brevemente los posibles factores dietéticos en su etiología. La desnutrición es muy prevalente en la EII, especialmente en la enfermedad de Crohn. En algunos pacientes se observan mayores requerimientos de energía y proteínas. El manejo de la desnutrición en la EII se considera dentro del contexto general de apoyo a los pacientes desnutridos. Se recomienda fuertemente el tratamiento de la deficiencia de hierro (por vía parenteral, si es necesario). Sin embargo, no se aconseja la prescripción de rutina de una dieta especial en la EII. La nutrición parenteral está indicada solo cuando la nutrición enteral ha fallado o es imposible. El manejo perioperatorio recomendado de los pacientes con EII sometidos a cirugía se hace de acuerdo con la guía general de la ESPEN para pacientes sometidos a cirugía abdominal. Los probióticos pueden ser útiles en la CU pero no en la enfermedad de Crohn. El tratamiento primario con nutrición para tratar la EII no está respaldado en la colitis ulcerosa, aunque está moderadamente bien soportado en la enfermedad de Crohn, especialmente en los niños, donde las consecuencias adversas de la terapia con esteroides son proporcionalmente mayores. Sin embargo, las dietas de exclusión generalmente no se recomiendan y hay poca evidencia que respalde cualquier fórmula de nutrición en particular cuando se realizan regímenes nutricionales. Conclusiones: los datos objetivos disponibles para guiar el apoyo nutricional y la terapia nutricional primaria en la EII se presentan como 64 recomendaciones, de las cuales 9 son recomendaciones muy fuertes (grado A), 22 son recomendaciones fuertes (grado B) y 12 se basan solo en evidencia escasa (grado 0); 21 recomendaciones son recomendaciones de buenas prácticas (GPP).

We present a broad class of semi-parametric models for time series of random sums of positive variables. Our methodology allows the number of terms inside the sum to be time-varying and is therefore well suited to many examples encountered in the natural sciences. We study the stability properties of the models and provide a valid statistical inference procedure to estimate the model parameters. It is shown that the proposed quasi-maximum likelihood estimator is consistent and asymptotically Gaussian distributed. This work is complemented by simulation results and applied to time series representing growth rates of white spruce (Picea glauca) trees from a few dozen sites in Quebec (Canada). This time series spans 41 years, including one major spruce budworm (Choristoneura fumiferana) outbreak between 1968 and 1991. We found significant growth reductions related to budworm-induced defoliation up to two years post-outbreak. Our results also revealed the positive effects of maximum summer temperature, precipitation, and the climate moisture index on white spruce growth. We also identified the negative effects of the climate moisture index in the spring and the maximum temperature of the previous summer. However, the model's performance on this data set was not improved when the interactions between climate and defoliation on growth were considered. This study represents a major advance in our understanding of budworm-climate-tree interactions and provides a useful tool to project the combined effects of climate and insect defoliation on tree growth in a context of greater frequency and severity of outbreaks coupled with the anticipated increases in temperature.

BACKGROUND We recently demonstrated that the odds of contracting coronavirus disease 2019 (COVID-19) in patients with celiac disease (CeD) is similar to that of the general population. However, how patients with CeD perceive their COVID-19 risk may differ from their actual risk. AIM To investigate risk perceptions of contracting COVID-19 in patients with CeD and determine the factors that may influence their perception. METHODS We distributed a survey throughout 10 countries between March and June 2020 and collected data on demographics, diet, COVID-19 testing, and risk perceptions of COVID-19 in patients with CeD. Participants were recruited through various celiac associations, clinic visits, and social media. Risk perception was assessed by asking individuals whether they believe patients with CeD are at an increased risk of contracting COVID-19 when compared to the general population. Logistic regression was used to determine the influencing factors associated with COVID-19 risk perception, such as age, sex, adherence to a gluten-free diet (GFD), and comorbidities such as cardiac conditions, respiratory conditions, and diabetes. Data was presented as adjusted odds ratios (aORs) RESULTS A total of 10737 participants with CeD completed the survey. From them, 6019 (56.1%) patients with CeD perceived they were at a higher risk or were unsure if they were at a higher risk of contracting COVID-19 compared to the non-CeD population. A greater proportion of patients with CeD perceived an increased risk of contracting COVID-19 when compared to infections in general due to their CeD (56.1% vs 26.7%, P < 0.0001). Consequently, 34.8% reported taking extra COVID-19 precautions as a result of their CeD. Members of celiac associations were less likely to perceive an increased risk of COVID-19 when compared to non-members (49.5% vs 57.4%, P < 0.0001). Older age (aOR: 0.99; 95%CI: 0.99 to 0.99, P < 0.001), male sex (aOR: 0.84; 95%CI: 0.76 to 0.93, P = 0.001), and strict adherence to a GFD (aOR: 0.89; 95%CI: 0.82 to 0.96, P = 0.007) were associated with a lower perception of COVID-19 risk and the presence of comorbidities was associated with a higher perception of COVID-19 risk (aOR: 1.38; 95%CI: 1.22 to 1.54, P < 0.001). CONCLUSION Overall, high levels of risk perceptions, such as those found in patients with CeD, may increase an individual's pandemic-related stress and contribute to negative mental health consequences. Therefore, it is encouraged that public health officials maintain consistent communication with the public and healthcare providers with the celiac community. Future studies specifically evaluating mental health in CeD could help determine the consequences of increased risk perceptions in this population.

Monitoring of forest response to gradual environmental changes or abrupt disturbances provides insights into how forested ecosystems operate and allows for quantification of forest health. In this chapter, we provide an overview ofSmartforestsCanada, a national-scale research network consisting of regional investigators who support a wealth of existing and new monitoring sites. The objectives ofSmartforestsare threefold: (1) establish and coordinate a network of high-precision monitoring plots across a 4400 km gradient of environmental and forest conditions, (2) synthesize the collected multivariate observations to examine the effects of global changes on complex above- and belowground forest dynamics and resilience, and (3) analyze the collected data to guide the development of the next-generation forest growth models and inform policy-makers on best forest management and adaptation strategies. We present the methodological framework implemented inSmartforeststo fulfill the aforementioned objectives. We then use an example from a temperate hardwoodSmartforestssite in Quebec to illustrate our approach for climate-smart forestry. We conclude by discussing how information from theSmartforestsnetwork can be integrated with existing data streams, from within Canada and abroad, guiding forest management and the development of climate change adaptation strategies.

The World Health Organization declared coronavirus disease-2019 (COVID-19) a global pandemic in March 2020. Since then, there are more than 34 million cases of COVID-19 leading to more than 1 million deaths worldwide. Numerous studies suggest that celiac disease (CeD), a chronic immune-mediated gastrointestinal condition triggered by gluten, is associated with an increased risk of respiratory infections.(1-3) However, how it relates to the risk of COVID-19 is unknown. To address this gap, we conducted a cross-sectional study to evaluate whether patients with self-reported CeD are at an increased risk of contracting COVID-19.

Sapwood characteristics, such as sapwood area as well as thermal and hydraulic conductivity, are linked to species-specific hydraulic function and resource allocation to water transport tissues (xylem). These characteristics are often unknown and thus a major source of uncertainty in sap flow data processing and transpiration estimates because bulk rather than species-specific values are usually applied. Here, we analyzed the sapwood characteristics of fifteen common tree species in eastern North America from different taxonomic (i.e., angiosperms and gymnosperms) and xylem porosity groups (i.e., tracheid-bearing, diffuse- or ring-porous species) and we assessed how uncertainties in sapwood characteristics involved in sap flow calculations are propagated in tree water use estimates. We quantified their sapwood area changes with stem diameter (allometric scaling) and thermal conductivity. We combined these measurements with species-specific values of wood density and hydraulic conductivity found in the literature and assessed the role of wood anatomy in orchestrating their covariation. Using an example sap flow dataset from tree species with different xylem porosity, we assessed the sensitivity of tree water use estimates to sapwood characteristics and their interactions. Angiosperms (ring- and diffuse-porous species), with specialized vessels for water transport, showed a steeper relationship (scaling) between tree stem diameter and sapwood area in comparison to gymnosperms (tracheid-bearing species). Gymnosperms (angiosperms) were characterized by lower (higher) wood density and higher (lower) sapwood moisture content, resulting in non-significant differences in sapwood thermal conductivity between taxonomic and xylem porosity groups. Clustering of species sapwood characteristics based on taxonomic or xylem porosity groups and constraining these parameters could facilitate more accurate sap flow calculations and tree water use estimates. When combined with an increasing number of sap flow observations, these findings should improve tree- and landscape-level transpiration estimates, leading to more robust partitioning of terrestrial water fluxes.