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The island of Newfoundland, Canada, is known as an area with high lichen species richness; however, most of this diversity is known from coastal regions where the ocean creates a maritime climate. The central part of the island has a more continental climate and is also the part of the province with the highest levels of industrial forest harvest and mining activities. For these reasons, it has not been an area considered to have high lichen diversity. Here, we show how local Mi'kmaw knowledge in collaboration with western scientific expertise facilitated a two-eyed seeing approach (Etuaptmumk) that yielded the discovery of overlooked lichen diversity in Central Newfoundland. Surveys by the authors throughout 2023 yielded collections of 175 species of lichenized, lichenicolous and allied fungi from the area known as Charlie's Place. Of these, there is a high proportion of cyanolichens (13%) and calicioids (11%), indicating high ecological value and potential old growth/ancient forest status. In addition, we report 19 new species records for the province, two of which (Chaenothecopsis vainioana and Myrionora albidula) are new records for Canada. Overall, the survey work reported here suggests that Charlie's Place should be a priority area for protection within the context of Central Newfoundland. This work also illustrates the value of research under the framework of Etuaptmumk and the benefits of combining local Indigenous and western scientific knowledge. The political, logistical, and financial support of Qalipu First Nation was key to the success of this work. [ABSTRACT FROM AUTHOR]

Black spruce (Picea mariana (Mill.) B.S.P.) is the dominant conifer species across a large part of North American boreal forests, providing many goods and services essential to human activities, and playing a major climatic role through the global carbon cycle. However, a comprehensive synthesis of the effects of climate change on black spruce has not yet been undertaken. The dynamics of black spruce are influenced by various living (biotic) and non-living (abiotic) factors, as well as their combined effects, which are particularly responsive to changes in climate. Climate change predictions suggest that northern ecosystems will experience the world's most significant impact. Therefore, black spruce is likely to undergo profound disruptions in its growth and mortality rate in the next few decades, resulting in significant changes in forestry and carbon storage. However, these changes will not be uniform throughout the entire distribution of the species. Future changes in temperature and precipitation will create more stress for water availability in the boreal forests of western and central North America than in their eastern counterparts. Thus, significant longitudinal and latitudinal gradients in tree growth and mortality variability are expected throughout the range of the species. This literature review aims to summarise the impacts of climate change on individual tree growth and mortality of this major species. While enhanced black spruce productivity could occur through both increased air temperature and nitrogen mineralisation in the soil, moisture limitation in central and western North America will result in significant growth reduction and mortality events across these regions. Conversely, under the expected climate change scenarios, black spruce forests may be more resilient in eastern North America, where climatic conditions appear more suitable, particularly in their northernmost range. In this review, we identify current research gaps for some disturbances, which should be addressed to better understand the impact of climate change on black spruce. Finally, we identify issues associated with sustainable forest management and the maintenance of black spruce under projected future climate changes. [ABSTRACT FROM AUTHOR]

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Copyright of Journal of Ecology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Tree-ring time series provide long-term, annually resolved information on the growth of trees. When sampled in a systematic context, tree-ring data can be scaled to estimate the forest carbon capture and storage of landscapes, biomes, and—ultimately—the globe. A systematic effort to sample tree rings in national forest inventories would yield unprecedented temporal and spatial resolution of forest carbon dynamics and help resolve key scientific uncertainties, which we highlight in terms of evidence for forest greening (enhanced growth) versus browning (reduced growth, increased mortality). We describe jump-starting a tree-ring collection across the continent of North America, given the commitments of Canada, the United States, and Mexico to visit forest inventory plots, along with existing legacy collections. Failing to do so would be a missed opportunity to help chart an evidence-based path toward meeting national commitments to reduce net greenhouse gas emissions, urgently needed for climate stabilization and repair. [ABSTRACT FROM AUTHOR]

Copyright of Botany is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract Background Endothelial function has been shown to be a highly sensitive marker for the overall cardiovascular risk of an individual. Furthermore, there is evidence of important sex differences in endothelial function that may underlie the differential presentation of cardiovascular disease (CVD) in women relative to men. As such, measuring endothelial function may have sex-specific prognostic value for the prediction of CVD events, thus improving risk stratification for the overall prediction of CVD in both men and women. The primary objective of this study is to assess the clinical utility of the forearm hyperaemic reactivity (FHR) test (a proxy measure of endothelial function) for the prediction of CVD events in men vs. women using a novel, noninvasive nuclear medicine -based approach. It is hypothesised that: 1) endothelial dysfunction will be a significant predictor of 5-year CVD events independent of baseline stress test results, clinical, demographic, and psychological variables in both men and women; and 2) endothelial dysfunction will be a better predictor of 5-year CVD events in women compared to men. Methods/Design A total of 1972 patients (812 men and 1160 women) undergoing a dipyridamole stress testing were recruited. Medical history, CVD risk factors, health behaviours, psychological status, and gender identity were assessed via structured interview or self-report questionnaires at baseline. In addition, FHR was assessed, as well as levels of sex hormones via blood draw. Patients will be followed for 5 years to assess major CVD events (cardiac mortality, non-fatal MI, revascularization procedures, and cerebrovascular events). Discussion This is the first study to determine the extent and nature of any sex differences in the ability of endothelial function to predict CVD events. We believe the results of this study will provide data that will better inform the choice of diagnostic tests in men and women and bring the quality of risk stratification in women on par with that of men.

Copyright of Botany is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

During lichen surveys conducted in Terra Nova National Park, Newfoundland and Labrador, two new calicioid lichen species for the province were discovered, increasing the number of known calicioid species in the province to 35. One of the species, Chaenotheca brachypoda, was previously known in the Maritimes provinces, Ontario, and British Columbia within Canada. The other species, Sclerophora peronella, was known from Nova Scotia, Quebec, and British Columbia within Canada and is listed under Schedule 1 of the Canadian Species At Risk Act as Special Concern. A key to the calicioids of Newfoundland and Labrador is provided. Additional survey efforts should be made in the rest of the province to better understand each species' distribution. [ABSTRACT FROM AUTHOR]

Caribou lichens, Cladonia (Cladina) spp., are a slow-growing, vital winter forage for caribou that are likely to be influenced by global warming. However, the large-scale response of caribou lichens to changing global climate remains unclear. Here, we derived caribou lichen cover maps for two time periods ∼30 years apart (i.e., the late 1980 s, and 2020 s) using Landsat satellite imagery for a region (0.59 million km2) in Eastern Canada that includes all or portions of several boreal caribou population ranges. We restricted our assessment to regions with at least 10% lichen cover and evaluated differences between the two time periods. Results show that since the 1980 s satellite-derived lichen cover declined in 62% of the region evaluated, remained constant in 27%, and increased in 11%. Twenty-three percent of the lichen cover decrease occurred in areas that burned after 1980, while 77% of the decrease remains unexplained, with warming-induced shrub encroachment, and caribou presence and grazing both possible causes. Caribou lichen regeneration occurs within regions burned before the 1980 s. Given that shrubification and wildfire frequency are projected to continue increasing, further monitoring of the scale and scope of ongoing changes will help to clarify future patterns. However, our results strongly suggest that the amount of caribou lichens has declined overall. • Satellite detected caribou lichen cover declined by 50%+ in the study area. • Forest fires accounted for 23% of lichen cover decreases since the 1980 s. • The majority (77%) of lichen cover decreases remain unexplained. [ABSTRACT FROM AUTHOR]