Degradation and forgone removals increase the carbon impact of intact forest loss by 626%

Intact tropical forests, free from substantial anthropogenic influence, store and sequester large amounts of atmospheric carbon but are currently neglected in international climate policy. We show that between 2000 and 2013, direct clearance of intact tropical forest areas accounted for 3.2% of gross carbon emissions from all deforestation across the pantropics. However, full carbon accounting requires the consideration of forgone carbon sequestration, selective logging, edge effects, and defaunation. When these factors were considered, the net carbon impact resulting from intact tropical forest loss between 2000 and 2013 increased by a factor of 6 (626%), from 0.34 (0.37 to 0.21) to 2.12 (2.85 to 1.00) petagrams of carbon (equivalent to approximately 2 years of global land use change emissions). The climate mitigation value of conserving the 549 million ha of tropical forest that remains intact is therefore significant but will soon dwindle if their rate of loss continues to accelerate

Climate change alters impacts of extreme climate events on a tropical perennial tree crop

Anthropogenic climate change causes more frequent and intense fluctuations in the El Niño Southern Oscillation (ENSO). Understanding the effects of ENSO on agricultural systems is crucial for predicting and ameliorating impacts on lives and livelihoods, particularly in perennial tree crops, which may show both instantaneous and delayed responses. Using cocoa production in Ghana as a model system, we analyse the impact of ENSO on annual production and climate over the last 70 years. We report that in recent decades, El Niño years experience reductions in cocoa production followed by several years of increased production, and that this pattern has significantly shifted compared with prior to the 1980s. ENSO phase appears to affect the climate in Ghana, and over the same time period, we see corresponding significant shifts in the climatic conditions resulting from ENSO extremes, with increasing temperature and water stress. We attribute these changes to anthropogenic climate change, and our results illustrate the big data analyses necessary to improve understanding of perennial crop responses to climate change in general, and climate extremes in particular

Minimal information for studies of extracellular vesicles 2018 (MISEV2018):a position statement of the International Society for Extracellular Vesicles and update of the MISEV2014 guidelines

The last decade has seen a sharp increase in the number of scientific publications describing physiological and pathological functions of extracellular vesicles (EVs), a collective term covering various subtypes of cell-released, membranous structures, called exosomes, microvesicles, microparticles, ectosomes, oncosomes, apoptotic bodies, and many other names. However, specific issues arise when working with these entities, whose size and amount often make them difficult to obtain as relatively pure preparations, and to characterize properly. The International Society for Extracellular Vesicles (ISEV) proposed Minimal Information for Studies of Extracellular Vesicles (“MISEV”) guidelines for the field in 2014. We now update these “MISEV2014” guidelines based on evolution of the collective knowledge in the last four years. An important point to consider is that ascribing a specific function to EVs in general, or to subtypes of EVs, requires reporting of specific information beyond mere description of function in a crude, potentially contaminated, and heterogeneous preparation. For example, claims that exosomes are endowed with exquisite and specific activities remain difficult to support experimentally, given our still limited knowledge of their specific molecular machineries of biogenesis and release, as compared with other biophysically similar EVs. The MISEV2018 guidelines include tables and outlines of suggested protocols and steps to follow to document specific EV-associated functional activities. Finally, a checklist is provided with summaries of key points

Mycorrhizal feedbacks influence global forest structure and diversity

One mechanism proposed to explain high species diversity in tropical systems is strong negative conspecific density dependence (CDD), which reduces recruitment of juveniles in proximity to conspecific adult plants. Although evidence shows that plant-specific soil pathogens can drive negative CDD, trees also form key mutualisms with mycorrhizal fungi, which may counteract these effects. Across 43 large-scale forest plots worldwide, we tested whether ectomycorrhizal tree species exhibit weaker negative CDD than arbuscular mycorrhizal tree species. We further tested for conmycorrhizal density dependence (CMDD) to test for benefit from shared mutualists. We found that the strength of CDD varies systematically with mycorrhizal type, with ectomycorrhizal tree species exhibiting higher sapling densities with increasing adult densities than arbuscular mycorrhizal tree species. Moreover, we found evidence of positive CMDD for tree species of both mycorrhizal types. Collectively, these findings indicate that mycorrhizal interactions likely play a foundational role in global forest diversity patterns and structure

Global importance of large-diameter trees

Aim: To examine the contribution of large‐diameter trees to biomass, stand structure, and species richness across forest biomes. Location: Global. Time period: Early 21st century. Major taxa studied: Woody plants. Methods: We examined the contribution of large trees to forest density, richness and biomass using a global network of 48 large (from 2 to 60 ha) forest plots representing 5,601,473 stems across 9,298 species and 210 plant families. This contribution was assessed using three metrics: the largest 1% of trees ≥ 1 cm diameter at breast height (DBH), all trees ≥ 60 cm DBH, and those rank‐ordered largest trees that cumulatively comprise 50% of forest biomass. Results: Averaged across these 48 forest plots, the largest 1% of trees ≥ 1 cm DBH comprised 50% of aboveground live biomass, with hectare‐scale standard deviation of 26%. Trees ≥ 60 cm DBH comprised 41% of aboveground live tree biomass. The size of the largest trees correlated with total forest biomass (r2 = .62, p < .001). Large‐diameter trees in high biomass forests represented far fewer species relative to overall forest richness (r2 = .45, p < .001). Forests with more diverse large‐diameter tree communities were comprised of smaller trees (r2 = .33, p < .001). Lower large‐diameter richness was associated with large‐diameter trees being individuals of more common species (r2 = .17, p = .002). The concentration of biomass in the largest 1% of trees declined with increasing absolute latitude (r2 = .46, p < .001), as did forest density (r2 = .31, p < .001). Forest structural complexity increased with increasing absolute latitude (r2 = .26, p < .001). Main conclusions: Because large‐diameter trees constitute roughly half of the mature forest biomass worldwide, their dynamics and sensitivities to environmental change represent potentially large controls on global forest carbon cycling. We recommend managing forests for conservation of existing large‐diameter trees or those that can soon reach large diameters as a simple way to conserve and potentially enhance ecosystem services

The social construction of diasporic identity: discourses of South Asian women about identity, racism and racialism

Bibliography: p. 137-146The influx of people from "Third World" countries to North America has been termed a "diaspora" (Bhatia, 2002). Research on immigrant identity has relied on transcultural models ( e.g. Berry, 1997), while studies about immigrant experiences often focus on racism. However, existing research is limited because it isolates individuals from their social, historical, and cultural context. My study provides an alternative approach to current views ofdiasporic identity and social phenomena such as racism. Conversations oftwelve South Asian women were analyzed using discourse analysis. Findings showed that participants claimed multiple identities. "Canadian" identity was drawn upon in formal, public situations, while "South Asian" identity was preferred in informal, private situations. Tensions ofpublic/private and Canadian/South Asian also factored into talk about racism. In ambiguous social and work situations, participants often denied that racism had occurred by using discursive devices to explain away or qualify negative experiences, thus avoiding victim status

"Outside" and "insider" perspectives on Canadian interracial relationships

Bibliography: p. 90-9

The impact of urban-based family medicine postgraduate rotations on rural preceptors/teachers

Background: The use of rural rotations within urban-based postgraduate programs is the predominant response of medical education to the health needs of underserved rural populations.  The broader impact on rural physicians who teach has not been reported.Methods: This study examined the personal, professional, and financial impact of a rural rotations for urban-based family medicine (UBFM) residents on Canadian rural teaching physicians. A survey was created and reviewed by community and academic rural physicians and a cohort of Canadian rural family physicians teaching UBFM residents was sampled. Survey data and free-text responses were assessed using quantitative and qualitative analyses.  Results: Participants with rural residency backgrounds perceived a negative impact of teaching UBFM (p = 0.02 personal and professional) and those in a primary rural environment (as defined below) perceived impact as positive (p < 0.001). Rural preceptors often held contrasting attitudes towards learners with negative judgements counter-balanced by positive thoughts. Duration in practice and of teaching experience did not have a significant impact on ratings.Conclusion: Being a rural preceptor of UBFM residents is rewarding but also stressful. The preceptor location of training and scope of practice appears to influence the impact of UBFM residents.Contexte : L’introduction de stages en milieu rural pour les résidents qui effectuent leur formation postdoctorale dans un centre urbain constitue la solution principale adoptée en matière d’éducation médicale pour répondre aux besoins des populations rurales mal desservies. L’impact plus large de ces stages sur les médecins enseignants en milieu rural n’a pas été documenté.Méthodes : Cette étude examine les répercussions personnelles, professionnelles et financières du stage réalisé en milieu rural par les résidents de médecine familiale en milieu urbain (MFMU) sur les médecins enseignants en milieu rural au Canada. Un sondage a été créé et revu par des médecins universitaires et communautaires en milieu rural et une cohorte de médecins de famille ruraux enseignant à des résidents de médecine familiale en milieu urbain a été échantillonnée. Les données du sondage et les réponses ouvertes obtenues ont fait l’objet d’analyses quantitative et qualitative.Résultats : Tandis que les participants possédant une expérience de résidence en milieu rural ont perçu l’effet négatif du fait d’enseigner aux résidents de MFMU (p = 0,02 personnel et professionnel), ceux qui exercent dans un environnement rural primaire (tel que défini ci-dessous) en ont une perception positive (p<0,001). Les superviseurs en milieu rural avaient souvent des attitudes contrastées envers les apprenants, des aspects positifs compensant certains jugements négatifs. La durée d’exercice et l’expérience en l’enseignement n’ont pas eu d’impact significatif sur les évaluations.Conclusion : Être un superviseur en milieu rural de résidents en MFMU est gratifiant, mais aussi stressant. Le lieu de formation et le champ d’exercice du superviseur semblent déterminer l’effet qu’ont les stages de résidents de MFMU sur ces superviseurs