volcano

火山
  • 文章类型: Journal Article
    Chichon火山包含几种热表现,包括酸性火山口湖。在这里,我们报告了“CandidatusAramenussp。”的宏基因组组装基因组。CH1,“一种来自Chichon火山的火山口湖的沙丁硫古细菌。在这项研究中,我们从墨西哥南部的一个热区产生了一个新的Aramenus基因组序列。
    The Chichon volcano contains several thermal manifestations including an acidic crater lake. Here we report a metagenome-assembled genome of \"Candidatus Aramenus sp. CH1,\" a Sulfolobales archaeon inhabiting the crater lake from the Chichon volcano. In this study, we generated a novel Aramenus genome sequence from a thermal area in Southern Mexico.
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  • 文章类型: Journal Article
    托尔图拉·阿特维伦斯(Sm。)林德。是生物土壤结皮的重要组成部分,对旱地栖息地的干燥具有非凡的耐受性。然而,仍然缺乏这种耐干燥(DT)苔藓的细胞器基因组的知识。这里,我们组装了第一个报告的Tortula细胞器基因组,并在Pottiaceae家族中进行了全面分析。T.atrovirens在Pottiaceae中表现出第二大叶绿体基因组(129,646bp),与其他陆地植物相比,其有丝分裂基因组(105,877bp)和其他苔藓的大小较小。T.atrovirens的叶绿体和线粒体基因组的特征在于IR边界的扩展和不存在大重复序列介导的同源重组。通过作图RNA-seq数据检测到总共57个RNA编辑位点。此外,该基因的含量和顺序在Pottiaceae细胞器基因组中高度保守。系统发育分析表明苔藓植物是共生的,他们的三个血统(角,苔藓,和苔藓)和维管植物形成连续的姐妹进化枝。Timmiellaanomala显然与单系pottiaceae分开,和T.atrovirens与Pottioideae内的丝状体紧密相关。此外,我们检测到四个候选分子标记的高变区。我们的发现为T.atrovirens的细胞器基因组和Pottiaceae家族中的进化关系提供了有价值的见解,促进未来从苔藓植物中发现DT遗传资源。
    Tortula atrovirens (Sm.) Lindb. is an important component of biological soil crusts and possesses an extraordinary tolerance against desiccation in dryland habitats. However, knowledge of the organelle genome of this desiccation-tolerant (DT) moss is still lacking. Here, we assembled the first reported Tortula organelle genome and conducted a comprehensive analysis within the Pottiaceae family. T. atrovirens exhibited the second largest chloroplast genome (129,646 bp) within the Pottiaceae, whereas its mitogenome (105,877 bp) and those of other mosses were smaller in size compared to other land plants. The chloroplast and mitochondrial genomes of T. atrovirens were characterized by the expansion of IR boundaries and the absence of homologous recombination-mediated by large repeats. A total of 57 RNA editing sites were detected through mapping RNA-seq data. Moreover, the gene content and order were highly conserved among the Pottiaceae organelle genomes. Phylogenetic analysis showed that bryophytes are paraphyletic, with their three lineages (hornworts, mosses, and liverworts) and vascular plants forming successive sister clades. Timmiella anomala is clearly separated from the monophyletic Pottiaceae, and T. atrovirens is closely related to Syntrichia filaris within the Pottioideae. In addition, we detected four hypervariable regions for candidate-molecular markers. Our findings provide valuable insights into the organelle genomes of T. atrovirens and the evolutionary relationships within the Pottiaceae family, facilitating future discovery of DT genetic resources from bryophytes.
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  • 文章类型: Journal Article
    微生物生态学的主要挑战是了解微生物在群落组合中联系和相互作用的原理和过程。山区冰川中的微生物群落是独特的,是下游生态系统的第一批定殖者和养分富集驱动器。然而,山区冰川对气候扰动特别敏感,在过去40年中遭受了严重的退缩,迫使我们在冰川生态系统消失之前了解它们。这是厄瓜多尔安第斯冰川的第一项研究,提供了有关物理化学变量和海拔与细菌群落多样性和结构之间关系的见解。我们的研究涵盖了Cayambe火山群的极端安第斯海拔,从4783到5583。冰川土壤和冰样品用作16SrRNA基因扩增子文库的来源。我们发现(1)海拔高度对多样性和群落结构的影响,(2)存在少量与群落结构显著相关的营养物质,(3)冰川土壤和冰川冰在多样性和群落结构上存在显著差异,where,由香农γ-多样性分布量化,冰川土壤中的元群落显示出比冰川冰中更多的多样性;这种模式与前基质中变量的物理化学分布的较高变异性有关,(4)与高海拔或低海拔相关的明显丰富的属,可以作为气候变化研究的生物标志物。我们的结果提供了对这些未开发社区的首次评估,在它们由于冰川退缩和气候变化而可能消失之前。
    A major challenge in microbial ecology is to understand the principles and processes by which microbes associate and interact in community assemblages. Microbial communities in mountain glaciers are unique as first colonizers and nutrient enrichment drivers for downstream ecosystems. However, mountain glaciers have been distinctively sensitive to climate perturbations and have suffered a severe retreat over the past 40  years, compelling us to understand glacier ecosystems before their disappearance. This is the first study in an Andean glacier in Ecuador offering insights into the relationship of physicochemical variables and altitude on the diversity and structure of bacterial communities. Our study covered extreme Andean altitudes at the Cayambe Volcanic Complex, from 4,783 to 5,583 masl. Glacier soil and ice samples were used as the source for 16S rRNA gene amplicon libraries. We found (1) effects of altitude on diversity and community structure, (2) the presence of few significantly correlated nutrients to community structure, (3) sharp differences between glacier soil and glacier ice in diversity and community structure, where, as quantified by the Shannon γ-diversity distribution, the meta-community in glacier soil showed more diversity than in glacier ice; this pattern was related to the higher variability of the physicochemical distribution of variables in the former substrate, and (4) significantly abundant genera associated with either high or low altitudes that could serve as biomarkers for studies on climate change. Our results provide the first assessment of these unexplored communities, before their potential disappearance due to glacier retreat and climate change.
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  • 文章类型: Journal Article
    了解动物如何应对大规模的环境变化是难以实现的,因为过去几十年来,监测数据很少可用。如果有的话。这里,我们展示了各种古生态代理(例如同位素,来自阿根廷的安第斯秃鹰(Vulturgryphus)鸟粪矿床的地球化学和DNA)可用于探索繁殖地点的保真度以及环境变化对鸟类行为的影响。我们发现秃鹰至少在2200年前就开始使用筑巢地,大约1000年的嵌套频率从大约1650年放缓到现在的650年(年BP)。我们提供的证据表明,筑巢放缓与附近南部火山带火山活动增加的时期相吻合,这导致腐肉的可用性下降,并阻止了食腐鸟类。返回巢穴大约650年BP后,秃鹰的饮食从本地物种和海滩海洋动物的腐肉转移到欧洲定居者引入的牲畜(例如绵羊和牛)和外来食草动物(例如马鹿和欧洲野兔)的腐肉。目前,与过去相比,安第斯秃鹰的鸟粪中的铅浓度升高,这与与饮食转变有关的人类迫害有关。
    Understanding how animals respond to large-scale environmental changes is difficult to achieve because monitoring data are rarely available for more than the past few decades, if at all. Here, we demonstrate how a variety of palaeoecological proxies (e.g. isotopes, geochemistry and DNA) from an Andean Condor (Vultur gryphus) guano deposit from Argentina can be used to explore breeding site fidelity and the impacts of environmental changes on avian behaviour. We found that condors used the nesting site since at least approximately 2200 years ago, with an approximately 1000-year nesting frequency slowdown from ca 1650 to 650 years before the present (yr BP). We provide evidence that the nesting slowdown coincided with a period of increased volcanic activity in the nearby Southern Volcanic Zone, which resulted in decreased availability of carrion and deterred scavenging birds. After returning to the nest site ca 650 yr BP, condor diet shifted from the carrion of native species and beached marine animals to the carrion of livestock (e.g. sheep and cattle) and exotic herbivores (e.g. red deer and European hare) introduced by European settlers. Currently, Andean Condors have elevated lead concentrations in their guano compared to the past, which is associated with human persecution linked to the shift in diet.
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  • 文章类型: Journal Article
    2021年Fagradalsfjall火山喷发,冰岛,提供了一个案例研究,用于研究从一开始就将紧急火山遗址发展为旅游目的地的利益相关者之间的积极合作。本研究的利益相关者包括市政行为者和代表;土地所有者;商业旅游公司和运营商;联邦旅游部和环境与自然资源部,民事保护,搜索和救援。通过持续的访谈文本比较方法,在负责任和可持续的旅游框架内分析了这些利益相关者对管理过程的看法。Theresultsbringtolightissuesdeemedimportantduringthesitemanagementanddestinationprocessaroundconceptsofauthority,责任,安全,资金,和访问。根据利益相关者,新兴的Fagradalsfjall目的地的管理虽然最初被积极地认为在持续的可持续和负责任的管理方面存在差距,这可能会影响各个利益相关者团体参与目的地的持续发展。这项研究对冰岛及其他地区的其他新兴火山旅游景点也有影响。
    The 2021 volcanic eruption at Fagradalsfjall, Iceland, provides a case study for examining an active collaboration between stakeholders in the development of an emergent volcanic site into a tourism destination from its inception. Stakeholders for this research include municipal actors and representatives; landowners; commercial tour companies and operators; the Federal Ministry of Tourism and Ministry of Environment and Natural Resources, civil protection, and search and rescue. These stakeholder perceptions of the management process are analyzed within a responsible and sustainable tourism framework by a constant comparative method of interview text. The results bring to light issues deemed important during the site management and destination development process around concepts of authority, responsibility, safety, funding, and access. According to stakeholders, the management of the emergent Fagradalsfjall destination while positively perceived initially has gaps surrounding ongoing sustainable and responsible management that could have impacts on the participation of various stakeholder groups in the destination\'s ongoing development. This research has implications for other emergent volcanic tourist sites in Iceland and beyond.
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  • 文章类型: Journal Article
    雷达(SAR)卫星系统地获取可用于火山监测的图像,表征岩浆系统并可能在全球范围内预测喷发。然而,利用大型数据集受人工检查需求的限制,这意味着信息的及时传播是具有挑战性的。在这里,我们自动处理Sentinel-1卫星在5年内(2015-2020年)获取的超过1000座火山的约600,000张图像,并使用该数据集来演示机器学习在检测变形信号方面的适用性和局限性。在最常见的16座火山中,经历了5次喷发,6显示缓慢变形,2个具有非火山变形,3个具有大气伪影。整个数据集的检测阈值为5.9cm,相当于5年研究期间1.2厘米/年的速度。然后,我们使用大型测试数据集来探索大气条件的影响,土地覆盖和信号特征的可检测性,发现机器学习算法的性能主要受到可用数据质量的限制,连贯性差和信号缓慢尤其具有挑战性。系统获取的不断扩大的数据集,经过处理和标记的图像将能够以前所未有的规模对火山监测信号进行定量分析,但定制的处理将需要为常规监测应用程序。
    UNASSIGNED:在线版本包含补充材料,可在10.1007/s00445-022-01608-x获得。
    Radar (SAR) satellites systematically acquire imagery that can be used for volcano monitoring, characterising magmatic systems and potentially forecasting eruptions on a global scale. However, exploiting the large dataset is limited by the need for manual inspection, meaning timely dissemination of information is challenging. Here we automatically process ~ 600,000 images of > 1000 volcanoes acquired by the Sentinel-1 satellite in a 5-year period (2015-2020) and use the dataset to demonstrate the applicability and limitations of machine learning for detecting deformation signals. Of the 16 volcanoes flagged most often, 5 experienced eruptions, 6 showed slow deformation, 2 had non-volcanic deformation and 3 had atmospheric artefacts. The detection threshold for the whole dataset is 5.9 cm, equivalent to a rate of 1.2 cm/year over the 5-year study period. We then use the large testing dataset to explore the effects of atmospheric conditions, land cover and signal characteristics on detectability and find that the performance of the machine learning algorithm is primarily limited by the quality of the available data, with poor coherence and slow signals being particularly challenging. The expanding dataset of systematically acquired, processed and flagged images will enable the quantitative analysis of volcanic monitoring signals on an unprecedented scale, but tailored processing will be needed for routine monitoring applications.
    UNASSIGNED: The online version contains supplementary material available at 10.1007/s00445-022-01608-x.
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  • 文章类型: Journal Article
    熔岩管网络是加拉帕戈斯群岛最未经开发的自然奇观之一。这里,我们提供了第一个形态学,矿物学,以及对加拉帕戈斯火山洞穴中的长齿茎进行生物地球化学评估,以了解它们的结构,composition,和起源,以及鉴定保存在鞘膜中的有机分子。矿物学分析表明,来自Bellavista和皇家棕榈洞的月乳和珊瑚类长骨由方解石组成,蛋白石A,和少量粘土矿物.细胞外聚合物,细菌化石,二氧化硅微球,和硅质矿物上的细胞印记证明了微生物-矿物相互作用和生物介导的二氧化硅沉淀。硅质和碳酸盐矿物之间的交替沉积层以及表面植被生物标志物和人为压力源的检测表明环境和人为变化(农业,人类排泄物,和洞穴参观)对这些独特的地下资源。稳定同位素分析和Py-GC/MS是可靠识别生物标志物的关键,允许实施未来的保护政策。
    The network of lava tubes is one of the most unexploited natural wonders of the Galapagos Islands. Here, we provide the first morphological, mineralogical, and biogeochemical assessment of speleothems from volcanic caves of the Galapagos to understand their structure, composition, and origin, as well as to identify organic molecules preserved in speleothems. Mineralogical analyses revealed that moonmilk and coralloid speleothems from Bellavista and Royal Palm Caves were composed of calcite, opal-A, and minor amounts of clay minerals. Extracellular polymeric substances, fossilized bacteria, silica microspheres, and cell imprints on siliceous minerals evidenced microbe-mineral interactions and biologically-mediated silica precipitation. Alternating depositional layers between siliceous and carbonate minerals and the detection of biomarkers of surface vegetation and anthropogenic stressors indicated environmental and anthropogenic changes (agriculture, human waste, and cave visits) on these unique underground resources. Stable isotope analysis and Py-GC/MS were key to robustly identify biomarkers, allowing for implementation of future protection policies.
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  • 文章类型: Journal Article
    冰川构成了一个以低温为特征的多极端环境,高太阳辐射,缺乏营养,和低的水供应。然而,位于火山地区的冰川具有特殊的特征,因为火山为它们提供了热量和营养,使微生物群落高度适应这种环境的生长。对这些冰川生态系统的研究大多是在北半球的火山环境中进行的,包括冰岛和太平洋西北部。为了更好地知道,未充分开发的冰川生态系统的微生物多样性,并检查它们的具体特征是什么,我们研究了生活在欺骗岛火山冰川中的细菌群落的结构,南极洲,在堪察加半岛。除了地理坐标,许多其他冰川环境因素(如火山活动,高度,温度,pH值,或冰的化学成分),可以影响微生物群落的多样性和分布。最后,使用他们的分类分配,尝试比较这些微生物所涉及的生物地球化学循环的不同或相似程度。
    Glaciers constitute a polyextremophilic environment characterized by low temperatures, high solar radiation, a lack of nutrients, and low water availability. However, glaciers located in volcanic regions have special characteristics, since the volcanic foci provide them with heat and nutrients that allow the growth of microbial communities highly adapted to this environment. Most of the studies on these glacial ecosystems have been carried out in volcanic environments in the northern hemisphere, including Iceland and the Pacific Northwest. To better know, the microbial diversity of the underexplored glacial ecosystems and to check what their specific characteristics were, we studied the structure of bacterial communities living in volcanic glaciers in Deception Island, Antarctica, and in the Kamchatka peninsula. In addition to geographic coordinates, many other glacier environmental factors (like volcanic activity, altitude, temperature, pH, or ice chemical composition) that can influence the diversity and distribution of microbial communities were considered in this study. Finally, using their taxonomic assignments, an attempt was made to compare how different or similar are the biogeochemical cycles in which these microbiomes are involved.
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  • 文章类型: Journal Article
    如果经济学家在很大程度上未能预测或阻止2008年的全球金融危机,以及与2020年大流行相关的更灾难性的经济崩溃,那么该行业还缺少什么?这是激发这项调查的问题。具体来说,我们想强调四个灾难性风险-即,可能导致比2008年或2020年事件更大的全球灾难的风险。我们在这里检查的四个风险是:太空天气和太阳耀斑,超级火山喷发,高死亡率的流行病,和错位的人工智能。所有四个都有发生的非平凡概率,所有四个都可能导致灾难,可能与人类灭绝没有太大区别。不可避免地,幸运的是,这些灾难性事件还没有发生,因此,研究它们的文献必然更多的是推测性的,而不是基于经验观察。然而,这并不会使这些风险变得不那么真实。这项调查的动机是相信经济学家可以而且应该更系统地考虑这些风险,这样我们就可以设计出适当的方法来防止它们或减轻它们的潜在影响。
    If economists have largely failed to predict or prevent the Global Financial Crisis in 2008, and the more disastrous economic collapse associated with the pandemic of 2020, what else is the profession missing? This is the question that motivates this survey. Specifically, we want to highlight four catastrophic risks - i.e., risks that can potentially result in global catastrophes of a much larger magnitude than either of the 2008 or 2020 events. The four risks we examine here are: Space weather and solar flares, super-volcanic eruptions, high-mortality pandemics, and misaligned artificial intelligence. All four have a non-trivial probability of occurring and all four can lead to a catastrophe, possibly not very different from human extinction. Inevitably, and fortunately, these catastrophic events have not yet occurred, so the literature investigating them is by necessity more speculative and less grounded in empirical observations. Nevertheless, that does not make these risks any less real. This survey is motivated by the belief that economists can and should be thinking about these risks more systematically, so that we can devise the appropriate ways to prevent them or ameliorate their potential impacts.
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  • 文章类型: Journal Article
    Understanding the response of biomass allocation in current-year twigs is crucial for elucidating the plant life-history strategies under heterogeneous volcanic habitats. We aimed to test whether twig biomass allocation, within-leaf biomass allocation, and the size-number trade-off of Betula platyphylla would be influenced. We measured twig traits of B. platyphylla in Wudalianchi volcanic kipuka, the lava platform, and Shankou lake in northeastern China using standardized major axis analyses. The results showed that the leaf number, total lamina mass (TLAM), stem mass (SM), and twig mass (TM) were significantly different between the three habitats and were greatest in kipuka with abundant soil nutrients. TLAM and SM scaled allometrically with respect to TM, while the normalization constants of the lava platform differ significantly between kipuka and Shankou lake, which showed that under certain TM, leaves gain more biomass in the lava platform. However, within the leaf, individual lamina mass (ILM) scaled isometrically with respect to individual petiole mass (IPM) in kipuka and the lava platform, but ILM scaled allometrically to IPM in Shankou lake. Our results indicated that inhabitats influenced the twig traits and biomass allocation and within-leaf biomass allocation are strategies for plants to adapt to volcanic heterogeneous habitats.
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