keyword
MENU ▼
Read by QxMD icon Read
search

Permafrost

keyword
https://www.readbyqxmd.com/read/27933054/nifh-harboring-bacterial-community-composition-across-an-alaskan-permafrost-thaw-gradient
#1
C Ryan Penton, Caiyun Yang, Liyou Wu, Qiong Wang, Jin Zhang, Feifei Liu, Yujia Qin, Ye Deng, Christopher L Hemme, Tianling Zheng, Edward A G Schuur, James Tiedje, Jizhong Zhou
Since nitrogen (N) is often limiting in permafrost soils, we investigated the N2-fixing genetic potential and the inferred taxa harboring those genes by sequencing nifH gene fragments in samples taken along a permafrost thaw gradient in an Alaskan boreal soil. Samples from minimally, moderately and extensively thawed sites were taken to a depth of 79 cm to encompass zones above and below the depth of the water table. NifH reads were translated with frameshift correction and 112,476 sequences were clustered at 5% amino acid dissimilarity resulting in 1,631 OTUs...
2016: Frontiers in Microbiology
https://www.readbyqxmd.com/read/27932654/draft-genome-sequence-of-antarctic-methanogen-enriched-from-dry-valley-permafrost
#2
Joy Buongiorno, Jordan T Bird, Kirill Krivushin, Victoria Oshurkova, Victoria Shcherbakova, Elizaveta M Rivkina, Karen G Lloyd, Tatiana A Vishnivetskaya
A genomic reconstruction belonging to the genus Methanosarcina was assembled from metagenomic data from a methane-producing enrichment of Antarctic permafrost. This is the first methanogen genome reported from permafrost of the Dry Valleys and can help shed light on future climate-affected methane dynamics.
December 8, 2016: Genome Announcements
https://www.readbyqxmd.com/read/27913019/persistent-organic-pollutants-in-shallow-percolated-water-of-the-alps-karst-system-zugspitze-summit-germany
#3
Walkiria Levy, Marchela Pandelova, Bernhard Henkelmann, Silke Bernhöft, Norbert Fischer, Felix Antritter, Karl-Werner Schramm
In the German Calcareous Alps at the Zugspitze, percolated water close to a permafrost bedrock in a tunnel system was monitored long-term for polychlorinated dibenzo-p-dioxins (PCDD), polychlorinated dibenzofurans (PCDF), polychlorinated biphenyls (PCB), polycyclic aromatic hydrocarbons (PAH), and 28 organochlorine pesticides (OCP). Semi-permeable membrane devices (SPMD) were deployed in a temporary surface water system at the Zugspitze plateau and analysed for PCB, PAH, and OCP. The high-volume water sampling was successfully implemented and all compounds were identified in the water percolated through the Karst system...
November 30, 2016: Science of the Total Environment
https://www.readbyqxmd.com/read/27901306/plants-microorganisms-and-soil-temperatures-contribute-to-a-decrease-in-methane-fluxes-on-a-drained-arctic-floodplain
#4
Min Jung Kwon, Felix Beulig, Iulia Ilie, Marcus Wildner, Kirsten Küsel, Lutz Merbold, Miguel D Mahecha, Nikita Zimov, Sergey A Zimov, Martin Heimann, Edward A G Schuur, Joel E Kostka, Olaf Kolle, Ines Hilke, Mathias Göckede
As surface temperatures are expected to rise in the future, ice-rich permafrost may thaw, altering soil topography and hydrology and creating a mosaic of wet and dry soil surfaces in the Arctic. Arctic wetlands are large sources of CH4 , and investigating effects of soil hydrology on CH4 fluxes is of great importance for predicting ecosystem feedback in response to climate change. In this study, we investigate how a decade-long drying manipulation on an Arctic floodplain influences CH4 -associated microorganisms, soil thermal regimes, and plant communities...
November 7, 2016: Global Change Biology
https://www.readbyqxmd.com/read/27897191/massive-remobilization-of-permafrost-carbon-during-post-glacial-warming
#5
T Tesi, F Muschitiello, R H Smittenberg, M Jakobsson, J E Vonk, P Hill, A Andersson, N Kirchner, R Noormets, O Dudarev, I Semiletov, Ö Gustafsson
Recent hypotheses, based on atmospheric records and models, suggest that permafrost carbon (PF-C) accumulated during the last glaciation may have been an important source for the atmospheric CO2 rise during post-glacial warming. However, direct physical indications for such PF-C release have so far been absent. Here we use the Laptev Sea (Arctic Ocean) as an archive to investigate PF-C destabilization during the last glacial-interglacial period. Our results show evidence for massive supply of PF-C from Siberian soils as a result of severe active layer deepening in response to the warming...
November 29, 2016: Nature Communications
https://www.readbyqxmd.com/read/27886221/hydrocarbon-degraders-establish-at-the-costs-of-microbial-richness-abundance-and-keystone-taxa-after-crude-oil-contamination-in-permafrost-environments
#6
Sizhong Yang, Xi Wen, Yulan Shi, Susanne Liebner, Huijun Jin, Amedea Perfumo
Oil spills from pipeline ruptures are a major source of terrestrial petroleum pollution in cold regions. However, our knowledge of the bacterial response to crude oil contamination in cold regions remains to be further expanded, especially in terms of community shifts and potential development of hydrocarbon degraders. In this study we investigated changes of microbial diversity, population size and keystone taxa in permafrost soils at four different sites along the China-Russia crude oil pipeline prior to and after perturbation with crude oil...
November 25, 2016: Scientific Reports
https://www.readbyqxmd.com/read/27870556/twenty-species-of-hypobarophilic-bacteria-recovered-from-diverse-soils-exhibit-growth-under-simulated-martian-conditions-at-0-7%C3%A2-kpa
#7
Andrew C Schuerger, Wayne L Nicholson
Bacterial growth at low pressure is a new research area with implications for predicting microbial activity in clouds and the bulk atmosphere on Earth and for modeling the forward contamination of planetary surfaces like Mars. Here, we describe experiments on the recovery and identification of 20 species of bacterial hypobarophiles (def., growth under hypobaric conditions of approximately 1-2 kPa) in 10 genera capable of growth at 0.7 kPa. Hypobarophilic bacteria, but not archaea or fungi, were recovered from diverse soils, and high numbers of hypobarophiles were recovered from Arctic and Siberian permafrost soils...
November 21, 2016: Astrobiology
https://www.readbyqxmd.com/read/27862698/warming-of-subarctic-tundra-increases-emissions-of-all-three-important-greenhouse-gases-carbon-dioxide-methane-and-nitrous-oxide
#8
Carolina Voigt, Richard E Lamprecht, Maija E Marushchak, Saara E Lind, Alexander Novakovskiy, Mika Aurela, Pertti J Martikainen, Christina Biasi
Rapidly rising temperatures in the Arctic might cause a greater release of greenhouse gases (GHGs) to the atmosphere. To study the effect of warming on GHG dynamics, we deployed open-top chambers in a subarctic tundra site in Northeast European Russia. We determined carbon dioxide (CO2 ), methane (CH4 ), and nitrous oxide (N2 O) fluxes as well as the concentration of those gases, inorganic nitrogen (N) and dissolved organic carbon (DOC) along the soil profile. Studied tundra surfaces ranged from mineral to organic soils and from vegetated to unvegetated areas...
November 14, 2016: Global Change Biology
https://www.readbyqxmd.com/read/27829694/climigration-population-and-climate-change-in-arctic-alaska
#9
Lawrence C Hamilton, Kei Saito, Philip A Loring, Richard B Lammers, Henry P Huntington
Residents of towns and villages in Arctic Alaska live on "the front line of climate change." Some communities face immediate threats from erosion and flooding associated with thawing permafrost, increasing river flows, and reduced sea ice protection of shorelines. The term climigration, referring to migration caused by climate change, originally was coined for these places. Although initial applications emphasized the need for government relocation policies, it has elsewhere been applied more broadly to encompass unplanned migration as well...
2016: Population and Environment
https://www.readbyqxmd.com/read/27796925/vertical-distribution-of-bacterial-community-is-associated-with-the-degree-of-soil-organic-matter-decomposition-in-the-active-layer-of-moist-acidic-tundra
#10
Hye Min Kim, Min Jin Lee, Ji Young Jung, Chung Yeon Hwang, Mincheol Kim, Hee-Myong Ro, Jongsik Chun, Yoo Kyung Lee
The increasing temperature in Arctic tundra deepens the active layer, which is the upper layer of permafrost soil that experiences repeated thawing and freezing. The increasing of soil temperature and the deepening of active layer seem to affect soil microbial communities. Therefore, information on soil microbial communities at various soil depths is essential to understand their potential responses to climate change in the active layer soil. We investigated the community structure of soil bacteria in the active layer from moist acidic tundra in Council, Alaska...
November 2016: Journal of Microbiology / the Microbiological Society of Korea
https://www.readbyqxmd.com/read/27795957/resistance-of-permafrost-and-modern-acinetobacter-lwoffii-strains-to-heavy-metals-and-arsenic-revealed-by-genome-analysis
#11
Sofia Mindlin, Anatolii Petrenko, Anton Kurakov, Alexey Beletsky, Andrey Mardanov, Mayya Petrova
We performed whole-genome sequencing of five permafrost strains of Acinetobacter lwoffii (frozen for 15-3000 thousand years) and analyzed their resistance genes found in plasmids and chromosomes. Four strains contained multiple plasmids (8-12), which varied significantly in size (from 4,135 to 287,630 bp) and genetic structure; the fifth strain contained only two plasmids. All large plasmids and some medium-size and small plasmids contained genes encoding resistance to various heavy metals, including mercury, cobalt, zinc, cadmium, copper, chromium, and arsenic compounds...
2016: BioMed Research International
https://www.readbyqxmd.com/read/27770504/threshold-loss-of-discontinuous-permafrost-and-landscape-evolution
#12
Laura Chasmer, Chris Hopkinson
This study demonstrates linkages between the 1997/1998 El Niño/Southern Oscillation index and a threshold shift to increased permafrost loss within a southern Taiga Plains watershed, Northwest Territories, Canada. Three-dimensional contraction of permafrost plateaus and changes in vegetation structural characteristics are determined from multitemporal airborne Light Detection And Ranging (LiDAR) surveys in 2008, 2011 and 2015. Morphological changes in permafrost cover are compared with optical image analogues from 1970, 1977, 2000 and 2008 and time-series hydro-climate data...
October 22, 2016: Global Change Biology
https://www.readbyqxmd.com/read/27753534/new-member-of-the-hormone-sensitive-lipase-family-from-the-permafrost-microbial-community
#13
Lada E Petrovskaya, Ksenia A Novototskaya-Vlasova, Sultan Sh Gapizov, Elena V Spirina, Ekaterina V Durdenko, Elizaveta M Rivkina
Siberian permafrost is a unique environment inhabited with diverse groups of microorganisms. Among them, there are numerous producers of biotechnologically relevant enzymes including lipases and esterases. Recently, we have constructed a metagenomic library from a permafrost sample and identified in it several genes coding for potential lipolytic enzymes. In the current work, properties of the recombinant esterases obtained from this library are compared with the previously characterized lipase from Psychrobacter cryohalolentis and other representatives of the hormone-sensitive lipase family...
October 18, 2016: Bioengineered
https://www.readbyqxmd.com/read/27750393/proteomic-and-transcriptomic-investigations-on-cold-responsive-properties-of-the-psychrophilic-antarctic-bacterium-psychrobacter-sp-pamc-21119-at-subzero-temperatures
#14
Hye Yeon Koh, Hyun Park, Jun Hyuck Lee, Se Jong Han, Young Chang Sohn, Sung Gu Lee
Psychrobacter sp. PAMC 21119, isolated from Antarctic permafrost soil, grows and proliferates at subzero temperatures. However, its major mechanism of cold adaptation regulation remains poorly understood. We investigated the transcriptomic and proteomic responses of this species to cold temperatures by comparing profiles at -5°C and 20°C to understand how extreme microorganisms survive under subzero conditions. We found a total of 2,906 transcripts and 584 differentially expressed genes (≥ 2 fold, p <0...
October 17, 2016: Environmental Microbiology
https://www.readbyqxmd.com/read/27726788/history-of-smallpox-and-its-spread-in-human-populations
#15
Catherine Thèves, Eric Crubézy, Philippe Biagini
Smallpox is considered among the most devastating of human diseases. Its spread in populations, initiated for thousands of years following a probable transmission from an animal host, was concomitant with movements of people across regions and continents, trade and wars. Literature permitted to retrace the occurrence of epidemics from ancient times to recent human history, smallpox having affected all levels of past society including famous monarchs. The disease was officially declared eradicated in 1979 following intensive vaccination campaigns...
August 2016: Microbiology Spectrum
https://www.readbyqxmd.com/read/27725633/circumpolar-distribution-and-carbon-storage-of-thermokarst-landscapes
#16
D Olefeldt, S Goswami, G Grosse, D Hayes, G Hugelius, P Kuhry, A D McGuire, V E Romanovsky, A B K Sannel, E A G Schuur, M R Turetsky
Thermokarst is the process whereby the thawing of ice-rich permafrost ground causes land subsidence, resulting in development of distinctive landforms. Accelerated thermokarst due to climate change will damage infrastructure, but also impact hydrology, ecology and biogeochemistry. Here, we present a circumpolar assessment of the distribution of thermokarst landscapes, defined as landscapes comprised of current thermokarst landforms and areas susceptible to future thermokarst development. At 3.6 × 10(6) km(2), thermokarst landscapes are estimated to cover ∼20% of the northern permafrost region, with approximately equal contributions from three landscape types where characteristic wetland, lake and hillslope thermokarst landforms occur...
October 11, 2016: Nature Communications
https://www.readbyqxmd.com/read/27703168/determinants-of-carbon-release-from-the-active-layer-and-permafrost-deposits-on-the-tibetan-plateau
#17
Leiyi Chen, Junyi Liang, Shuqi Qin, Li Liu, Kai Fang, Yunping Xu, Jinzhi Ding, Fei Li, Yiqi Luo, Yuanhe Yang
The sign and magnitude of permafrost carbon (C)-climate feedback are highly uncertain due to the limited understanding of the decomposability of thawing permafrost and relevant mechanistic controls over C release. Here, by combining aerobic incubation with biomarker analysis and a three-pool model, we reveal that C quality (represented by a higher amount of fast cycling C but a lower amount of recalcitrant C compounds) and normalized CO2-C release in permafrost deposits were similar or even higher than those in the active layer, demonstrating a high vulnerability of C in Tibetan upland permafrost...
October 5, 2016: Nature Communications
https://www.readbyqxmd.com/read/27689625/the-positive-net-radiative-greenhouse-gas-forcing-of-increasing-methane-emissions-from-a-thawing-boreal-forest-wetland-landscape
#18
M Helbig, L Chasmer, N Kljun, W L Quinton, C C Treat, O Sonnentag
At the southern margin of permafrost in North America, climate change causes widespread permafrost thaw. Here, thawing permafrost in forested peat plateaus ("forest") leads to expansion of permafrost-free wetlands ("wetland") in boreal lowlands. Expanding wetland area with saturated and warmer organic soils is expected to increase landscape methane (CH4 ) emissions. Here, we quantify the thaw-induced increase in CH4 emissions for a boreal forest-wetland landscape in the southern Taiga Plains, Canada, and evaluate its impact on net radiative forcing relative to potential long-term net carbon dioxide (CO2 ) exchange...
September 30, 2016: Global Change Biology
https://www.readbyqxmd.com/read/27686416/allochthonous-carbon-is-a-major-regulator-to-bacterial-growth-and-community-composition-in-subarctic-freshwaters
#19
Toni Roiha, Sari Peura, Mathieu Cusson, Milla Rautio
In the subarctic region, climate warming and permafrost thaw are leading to emergence of ponds and to an increase in mobility of catchment carbon. As carbon of terrestrial origin is increasing in subarctic freshwaters the resource pool supporting their microbial communities and metabolism is changing, with consequences to overall aquatic productivity. By sampling different subarctic water bodies for a one complete year we show how terrestrial and algal carbon compounds vary in a range of freshwaters and how differential organic carbon quality is linked to bacterial metabolism and community composition...
September 30, 2016: Scientific Reports
https://www.readbyqxmd.com/read/27685441/a-naturally-occurring-cold-earth-spot-in-northern-china
#20
Fujun Niu, Guodong Cheng, Yonghong Niu, Mingyi Zhang, Jing Luo, Zhanju Lin
Permafrost is determined to a large extent by the Earth's surface temperature, therefore it distributes mainly in high altitude and latitude regions. However, stable, warm (about -1 °C) permafrost occurs within a scree slope in northern China that is more than 600 km south of the southernmost limit of latitudinal permafrost on the Eurasian Continent. It is at an elevation of only 900 m above sea level (ASL). The area has a mean annual air temperature (MAAT) of 6 to 8 °C. Thermal processes of the scree slope, investigated through field monitoring and numerical simulation, showed that the permafrost is caused by winter air convection within the porous rock deposits and is stable as air convection does not occur in summer time...
September 29, 2016: Scientific Reports
keyword
keyword
56631
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"