Sentences with word «oxic»

In the above citied letter to Nature the authors concluded out of their experiments: «Here we demonstrate using stable carbon isotopes that methane is readily formed in situ in terrestrial plants under oxic conditions by a hitherto unrecognized process.»
Lenski and his student Zachary Blount note that «E. coli cells can not grow on citrate under oxic conditions, and that inability has long been viewed as a defining characteristic of this important, diverse, and widespread species.»
He and his colleagues did not find a statistically significant increase in the proportion of oxic to anoxic water at the boundary between the Ediacaran and the Cambrian.
Rather than a gradual transition, the anoxic - to - oxic transition, triggered by a chance evolution occurrence, may have been a catastrophic event: the world's first biologically - caused climate disaster.
The Baltic Sea also alternates between redox states: it experienced various periods of low oxygen over the Holocene, but is currently subject to a human - induced period of anoxia, with its bottom waters largely oxic around 1900 CE (Conley et al., 2009).
If we start out with a balanced system which contains frozen water at the poles, the mid to high latitudes begin to thaw, triggering soil greenhouse gas feedbacks (permafrost thaw and following oxic and anoxic sources add to the greenhouse gas budget), a chronic linear process (which helps to accelerate changes of the equilibrium state, reduces the ability of the atmosphere to break down greenhouse gases — less hydroxide radicals).
Assembly of phylogenetic data from the earliest Triassic shows that prolonged and widespread anoxic intervals indeed promoted morphological novelty in soft - bodied benthos, which then provides the ancestral stock for subsequently skeletonised lineages to appear as innovations once oxic conditions became widespread and stable, so in turn promoting major evolutionary diversification.
At hydrothermal vents, anoxic water containing reduced compounds like methane or sulfide mix with oxic seawater and the bacterial harvest energy.
In addition, these cells are highly sensitive to oxygen and rapidly die when exposed to oxic conditions.
While many researchers believe the transition from an anoxic world to an oxic world occurred gradually, Joe Kirschvink (Caltech) and I have suggested instead — based on a critical analysis of the available data, with a strong dose of caution applied to the use of uniformitarian interpretations in such a radically different world — that the transition occurred rapidly (Kopp et al., 2005; Kirschvink and Kopp, 2008).
Aside from the origin of life itself, the transition from the anoxic Archean to the oxic Proterozoic is the most radical change to occur in the history of the Earth system.
Today our publication on «Oxic - anoxic regime shifts mediated by feedbacks between geochemical processes and microbial community dynamics» has been published in Nature Communications.
The seasonal distribution of marine Crenarchaeota in the oxic and ammonia - rich surface waters off Palmer Station, Antarctica [4], as well as a correlation of increasing crenarchaeal abundance with a nitrite (NO2 −) maximum are both consistent with the hypothesis that marine Crenarchaeota are capable of ammonia oxidation [25].
More dust, less sunlight, colder oceans, but more dust means that more dust falls on the oceans, which means the more iron fertilization of photosynthetic organisms there is, the higher the level of photosynthesis, so the more CO2 is converted into biomass, so more organic carbon falls to the sea bed, so the more atmospheric carbon disappears into the ocean sink, and also the wider the oxic band at the oceans surface and so more methane is oxidized on the way to the surface.
Organic matter diagenesis at the oxic / anoxic interface in coastal marine sediments, with emphasis on the role of burrowing animals
Dissolved methane is chemically unstable in the oxic water column of the ocean, but it has a lifetime of decades (shorter in high - flux environments)[Valentine et al., 2001], so if the methane is released shallow enough in the ocean, it has a good chance of escaping to the atmosphere.
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