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Northern peatlands have cooled the global climate by accumulating large quantities of soil carbon (C) over thousands of years. Maintaining the C sink function of these peatlands and their immense long‐term soil C stores is critical for achieving net‐zero global carbon dioxide (CO2) emissions by 2050 to mitigate climate warming. One‐quarter of the world's northern peatlands are in Canada, with these mostly intact ecosystems providing a global C service that is increasingly recognized as a critical part of nature‐based solutions to combat climate change. However, land‐use change and other disturbances threaten these globally important stores of "irrecoverable C" (that is, soil C lost to disturbance that will take centuries to recover). Inadequate policy safeguards to avoid conversion and degradation, and the limited quantification and reporting of peatland greenhouse‐gas emissions and removals, increase the vulnerability of these peatlands. Targeted policies from local to global scales will be needed for improved decision making and incentivizing long‐term C management of northern peatlands. [ABSTRACT FROM AUTHOR]

Natural wildfire regimes are important for ecosystem succession but can have negative ecological effects depending on fire characteristics. A portion of a granite rock barrens landscape that extends along the eastern shoreline of Georgian Bay, Lake Huron to eastern Ontario, Canada, burned in 2018 during a wildfire that affected >11,000 ha. This landscape is a biodiversity hotspot providing habitat for many species at risk where freshwater turtles nest in soil deposits in cracks and crevices in the bedrock dominated by moss (Polytrichum spp.) and lichen (Cladonia spp.) cover. To assess the initial effect of wildfire on freshwater turtle nesting habitat, we measured soil depths and estimated moss, lichen, and vascular plant cover at 2 morphology types (crevice, flat) in burned and unburned areas of the landscape. The probability that burned flat plots supported soil was near zero; the burned flat plots had 98% less soil volume compared to unburned flat plots. Although crevices were more resistant to soil loss, burned crevices still had a 15% lower probability of having soil and 35% less soil volume compared to unburned crevice plots. We estimated nest site availability by calculating the number of locations with shallow (5–10 cm), intermediate (10–20 cm), and deep (>20 cm) soils required for a small (5 cm × 5 cm) or medium (10 cm × 10 cm) nest chamber. Overall, the burned open rock barrens had 71–73% fewer sites with suitable soil depth and volume for a nest chamber of either size. Furthermore, burned plots had almost no lichen and moss cover but were dominated by bare soil, forbs, and jack pine (Pinus banksiana) seedlings. Although the loss of tree cover in previously forested areas may increase nest site availability for freshwater turtles in newly open areas, we suggest that organic soil combustion and soil erosion may require restoration activities in the post‐fire landscape to support successful nesting of at‐risk turtles. © 2020 The Wildlife Society. After an 11,000‐ha fire in a rock barrens landscape, the availability of nesting habitat for freshwater turtles was lower at burned compared to unburned sites, and the suitability of remaining potential nest sites was likely negatively affected through alterations in soil properties. Extensive organic soil combustion and soil erosion, leading to loss and alteration of nesting habitat, may require restoration activities in post‐fire landscapes to support successful nesting of at‐risk turtles. [ABSTRACT FROM AUTHOR]

Objective: The prevalence of incidental temporal bone disease on magnetic resonance imaging has been widely reported in the medical literature. Despite this, there currently is little evidence regarding incidental otological disease on computerized tomography (CT). Thus, the study aimed to review the CT prevalence of asymptomatic adult ear disease and evaluate the appropriateness of ear, nose, and throat (ENT) referral following its discovery.Study Design: Retrospective observational study of 468 CT scans.Methods: All CT head scans performed between January 2015 and January 2016 containing the keyword mastoid in the radiological report initially were recruited for the study. Scans performed in the pediatric population following head trauma or for otological indications were excluded, leaving 468 eligible radiological images. The presence of prior otological disease or referral subsequently was established using electronic patient records.Results: Mastoid and/or middle ear opacification was noted to be present in 62 patients (13%). Of these patients, 10 subsequently were found to have prior otological intervention or review. Following exclusion of these patients, the rate of incidental temporal bone disease was recorded as 11%.Conclusion: Data from this study suggests that incidental findings in an asymptomatic individual do not necessitate referral or further intervention. Furthermore, it is the author's recommendation that radiological findings be closely correlated with clinical examination to reduce false diagnosis and inappropriate referral to ENT.Level Of Evidence: 4. Laryngoscope, 127:2860-2865, 2017. [ABSTRACT FROM AUTHOR]

A suite of autogenic ecohydrological feedbacks and moss traits are important for protecting vast peatland carbon stocks following wildfire disturbance. Here, we examine how peat burn severity and water table depth (WTD) affect the strength of one such feedback—the hydrophobicity–evaporation feedback (HEF). The HEF is an evaporation‐limiting feedback known to minimize water loss following wildfire. The peatland surface becomes hydrophobic creating an evaporative cap and thereby reducing post‐fire evaporation; however, recent studies hypothesize that this is dependent on peat burn severity. To test this hypothesis, we studied plots along a peat burn severity gradient in a partially drained black spruce peatland that burned during the 2016 Fort McMurray Horse River wildfire. Evaporation rates were significantly lower in plots where hydrophobicity was present. Hydrophobicity was lowest in the severely burned area, and the average instantaneous evaporation rate (2.75 mm day−1) was significantly higher than moderately and typical‐lightly burned areas (0.82 and 1.64 mm day−1, respectively). Based on lab results, increasing WTD affected hydrophobicity within lightly burned (singed) feather moss samples but not in heavily burned feather moss, showing the importance of post‐fire ground cover and in situ WTD. Our results provide evidence of a burn severity threshold where increased depth of burn removes the feather moss evaporative cap and causes the HEF to break down. We argue that this threshold has important implications for boreal peatlands, which are predicted to undergo climate‐mediated pre‐fire drying and increasing burn severities, potentially leading to further carbon losses due to enhanced post‐fire drying and concomitant decomposition. [ABSTRACT FROM AUTHOR]