12 research outputs found

    Global fire emissions buffered by the production of pyrogenic carbon

    Get PDF
    Landscape fires burn 3–5 million km2 of the Earth’s surface annually. They emit 2.2 Pg of carbon per year to the atmosphere, but also convert a significant fraction of the burned vegetation biomass into pyrogenic carbon. Pyrogenic carbon can be stored in terrestrial and marine pools for centuries to millennia and therefore its production can be considered a mechanism for long-term carbon sequestration. Pyrogenic carbon stocks and dynamics are not considered in global carbon cycle models, which leads to systematic errors in carbon accounting. Here we present a comprehensive dataset of pyrogenic carbon production factors from field and experimental fires and merge this with the Global Fire Emissions Database to quantify the global pyrogenic carbon production flux. We found that 256 (uncertainty range: 196–340) Tg of biomass carbon was converted annually into pyrogenic carbon between 1997 and 2016. Our central estimate equates to 12% of the annual carbon emitted globally by landscape fires, which indicates that their emissions are buffered by pyrogenic carbon production. We further estimate that cumulative pyrogenic carbon production is 60 Pg since 1750, or 33–40% of the global biomass carbon lost through land use change in this period. Our results demonstrate that pyrogenic carbon production by landscape fires could be a significant, but overlooked, sink for atmospheric CO2

    Cell-type–specific eQTL of primary melanocytes facilitates identification of melanoma susceptibility genes

    Get PDF
    Most expression quantitative trait locus (eQTL) studies to date have been performed in heterogeneous tissues as opposed to specific cell types. To better understand the cell-type–specific regulatory landscape of human melanocytes, which give rise to melanoma but account for <5% of typical human skin biopsies, we performed an eQTL analysis in primary melanocyte cultures from 106 newborn males. We identified 597,335 cis-eQTL SNPs prior to linkage disequilibrium (LD) pruning and 4997 eGenes (FDR < 0.05). Melanocyte eQTLs differed considerably from those identified in the 44 GTEx tissue types, including skin. Over a third of melanocyte eGenes, including key genes in melanin synthesis pathways, were unique to melanocytes compared to those of GTEx skin tissues or TCGA melanomas. The melanocyte data set also identified trans-eQTLs, including those connecting a pigmentation-associated functional SNP with four genes, likely through cis-regulation of IRF4. Melanocyte eQTLs are enriched in cis-regulatory signatures found in melanocytes as well as in melanoma-associated variants identified through genome-wide association studies. Melanocyte eQTLs also colocalized with melanoma GWAS variants in five known loci. Finally, a transcriptome-wide association study using melanocyte eQTLs uncovered four novel susceptibility loci, where imputed expression levels of five genes (ZFP90, HEBP1, MSC, CBWD1, and RP11-383H13.1) were associated with melanoma at genome-wide significant P-values. Our data highlight the utility of lineage-specific eQTL resources for annotating GWAS findings, and present a robust database for genomic research of melanoma risk and melanocyte biology

    Bullying Prevention: A Summary of the Report of the National Academies of Sciences, Engineering and Medicine

    No full text
    Long tolerated as a rite of passage into adulthood, bullying is now recognized as a major and preventable public health problem. The consequences of bullying - for those who are bullied, the perpetrators of bullying, and the witnesses - include poor physical health, anxiety, depression, increased risk for suicide, poor school performance, and future delinquent and aggressive behavior. Despite ongoing efforts to address bullying at the law, policy, and programmatic levels, there is still much to learn about the consequences of bullying and the effectiveness of various responses. In 2016, the National Academies of Sciences, Engineering, and Medicine published a report entitled Preventing Bullying Through Science, Policy and Practice, which examined the evidence on bullying, its impact, and responses to date. This article summarizes the report\u27s key findings and recommendations related to bullying prevention

    Bullying Prevention: A Summary of the Report of the National Academies of Sciences, Engineering and Medicine

    No full text
    Long tolerated as a rite of passage into adulthood, bullying is now recognized as a major and preventable public health problem. The consequences of bullying - for those who are bullied, the perpetrators of bullying, and the witnesses - include poor physical health, anxiety, depression, increased risk for suicide, poor school performance, and future delinquent and aggressive behavior. Despite ongoing efforts to address bullying at the law, policy, and programmatic levels, there is still much to learn about the consequences of bullying and the effectiveness of various responses. In 2016, the National Academies of Sciences, Engineering, and Medicine published a report entitled Preventing Bullying Through Science, Policy and Practice, which examined the evidence on bullying, its impact, and responses to date. This article summarizes the report\u27s key findings and recommendations related to bullying prevention

    Fires prime terrestrial organic carbon for riverine export to the global oceans

    Get PDF
    Black carbon (BC) is a recalcitrant form of organic carbon (OC) produced by landscape fires. BC is an important component of the global carbon cycle because, compared to unburned biogenic OC, it is selectively conserved in terrestrial and oceanic pools. Here we show that the dissolved BC (DBC) content of dissolved OC (DOC) is twice greater in major (sub)tropical and high-latitude rivers than in major temperate rivers, with further significant differences between biomes. We estimate that rivers export 18 ± 4 Tg DBC year−1 globally and that, including particulate BC fluxes, total riverine export amounts to 43 ± 15 Tg BC year−1 (12 ± 5% of the OC flux). While rivers export ~1% of the OC sequestered by terrestrial vegetation, our estimates suggest that 34 ± 26% of the BC produced by landscape fires has an oceanic fate. Biogeochemical models require modification to account for the unique dynamics of BC and to predict the response of recalcitrant OC export to changing environmental conditions
    corecore