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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]

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]