scholarly journals The Geomycology of Elemental Cycling and Transformations in the Environment

2017 ◽  
pp. 371-386 ◽  
Keyword(s):  
Elemental Cycling

scholarly journals In Silico Geobacter sulfurreducens Metabolism and Its Representation in Reactive Transport Models

2008 ◽  
Vol 75 (1) ◽  
pp. 83-92 ◽  
Author(s):  
E. L. King ◽  
K. Tuncay ◽  
P. Ortoleva ◽  
C. Meile
Keyword(s):  
Reactive Transport ◽  
Cell Model ◽  
Cell Metabolism ◽  
Growth Dynamics ◽  
Growth Efficiency ◽  
Geobacter Sulfurreducens ◽  
Balance Model ◽  
Substrate Uptake ◽  
Elemental Cycling ◽  
Dynamic Cell

ABSTRACT Microbial activity governs elemental cycling and the transformation of many anthropogenic substances in aqueous environments. Through the development of a dynamic cell model of the well-characterized, versatile, and abundant Geobacter sulfurreducens, we showed that a kinetic representation of key components of cell metabolism matched microbial growth dynamics observed in chemostat experiments under various environmental conditions and led to results similar to those from a comprehensive flux balance model. Coupling the kinetic cell model to its environment by expressing substrate uptake rates depending on intra- and extracellular substrate concentrations, two-dimensional reactive transport simulations of an aquifer were performed. They illustrated that a proper representation of growth efficiency as a function of substrate availability is a determining factor for the spatial distribution of microbial populations in a porous medium. It was shown that simplified model representations of microbial dynamics in the subsurface that only depended on extracellular conditions could be derived by properly parameterizing emerging properties of the kinetic cell model.

scholarly journals The Surtsey Volcano Geothermal System: An Analogue to Constrain Elemental Cycling in Seamounts?

2020 ◽  
Author(s):  
Barbara Irene Kleine ◽  
Andri Stefánsson ◽  
Ríkey Kjartansdóttir ◽  
Simon Prause ◽  
Tobias Björn Weisenberger ◽  
...  
Keyword(s):  
Geothermal System ◽  
Elemental Cycling

Iron Formations as Palaeoenvironmental Archives

2021 ◽  
Author(s):  
Kaarel Mänd ◽  
Leslie J. Robbins ◽  
Noah J. Planavsky ◽  
Andrey Bekker ◽  
Kurt O. Konhauser
Keyword(s):  
Sedimentary Rocks ◽  
Scientific Understanding ◽  
Significant Part ◽  
Formation Mechanisms ◽  
Redox States ◽  
Elemental Cycling ◽  
Ancient Iron ◽  
Iron Formations ◽  
Palaeoenvironmental Conditions ◽  
Chemical Sediments

Ancient iron formations - iron and silica-rich chemical sedimentary rocks that formed throughout the Precambrian eons - provide a significant part of the evidence for the modern scientific understanding of palaeoenvironmental conditions in Archaean (4.0–2.5 billion years ago) and Proterozoic (2.5–0.539 billion years ago) times. Despite controversies regarding their formation mechanisms, iron formations are a testament to the influence of the Precambrian biosphere on early ocean chemistry. As many iron formations are pure chemical sediments that reflect the composition of the waters from which they precipitated, they can also serve as nuanced geochemical archives for the study of ancient marine temperatures, redox states, and elemental cycling, if proper care is taken to understand their sedimentological context.

scholarly journals The evolution of trait correlations constrains phenotypic adaptation to high CO 2 in a eukaryotic alga

2021 ◽  
Vol 288 (1953) ◽  
pp. 20210940
Author(s):  
Nathan G. Walworth ◽  
Jana Hinners ◽  
Phoebe A. Argyle ◽  
Suzana G. Leles ◽  
Martina A. Doblin ◽  
...  
Keyword(s):  
Food Webs ◽  
Predictive Model ◽  
Microbial Evolution ◽  
Fitness Landscapes ◽  
Significant Challenge ◽  
Eukaryotic Alga ◽  
Elemental Cycling ◽  
Adaptive Walks ◽  
Sheer Number ◽  
Trait Correlations

Microbes form the base of food webs and drive biogeochemical cycling. Predicting the effects of microbial evolution on global elemental cycles remains a significant challenge due to the sheer number of interacting environmental and trait combinations. Here, we present an approach for integrating multivariate trait data into a predictive model of trait evolution. We investigated the outcome of thousands of possible adaptive walks parameterized using empirical evolution data from the alga Chlamydomonas exposed to high CO 2 . We found that the direction of historical bias (existing trait correlations) influenced both the rate of adaptation and the evolved phenotypes (trait combinations). Critically, we use fitness landscapes derived directly from empirical trait values to capture known evolutionary phenomena. This work demonstrates that ecological models need to represent both changes in traits and changes in the correlation between traits in order to accurately capture phytoplankton evolution and predict future shifts in elemental cycling.

scholarly journals Effects of Ocean Acidification on Marine Biodiversity and Ecosystem Function

2011 ◽  
Author(s):  
James P. Barry ◽  
Stephen Widdicombe
Keyword(s):  
Ocean Acidification ◽  
Ecosystem Function ◽  
Environmental Changes ◽  
Biological Effects ◽  
Marine Ecosystems ◽  
Fishing Effort ◽  
Elemental Cycling ◽  
Biodiversity And Ecosystem Function ◽  
The Stability ◽  
And Function

The biodiversity of the oceans, including the striking variation in life forms from microbes to whales and ranging from surface waters to hadal trenches, forms a dynamic biological framework enabling the flow of energy that shapes and sustains marine ecosystems. Society relies upon the biodiversity and function of marine systems for a wide range of services as basic as producing the seafood we consume or as essential as generating much of the oxygen we breathe. Perhaps most obvious is the global seafood harvest totalling over 100 Mt yr–1 (82 and 20 Mt in 2008 for capture and aquaculture, respectively; FAO 2009) from fishing effort that expands more broadly and deeper each year as fishery stocks are depleted (Pauly et al. 2003). Less apparent ecosystem services linked closely to biodiversity and ecosystem function are waste processing and improved water quality, elemental cycling, shoreline protection, recreational opportunities, and aesthetic or educational experiences (Cooley et al. 2009). There is growing concern that ocean acidification caused by fossil fuel emissions, in concert with the effects of other human activities, will cause significant changes in the biodiversity and function of marine ecosystems, with important consequences for resources and services that are important to society. Will the effects of ocean acidification on ecosystems be similar to those arising from other environmental perturbations observed during human or earth history? Although changes in biodiversity and ecosystem function due to ocean acidification have not yet been widely observed, their onset may be difficult to detect amidst the variability associated with other human and non-human factors, and the greatest impacts are expected to occur as acidification intensifies through this century. In theory, large and rapid environmental changes are expected to decrease the stability and productivity of ecosystems due to a reduction in biodiversity caused by the loss of sensitive species that play important roles in energy flow (i.e. food web function) or other processes (e.g. ecosystem engineers; Cardinale et al. 2006). In practice, however, most research concerning the biological effects of ocean acidification has focused on aspects of the performance and survival of individual species during short-term studies, assuming that a change in individual performance will influence ecosystem function.

Analysis and Monitoring atmospheric gases in a high performing and versatile isotope ratio instrument

2021 ◽  
Author(s):  
Sam Barker ◽  
Phil Hackett ◽  
Will Price ◽  
Kathrin Rosenthal
Keyword(s):  
Climate Change ◽  
Carbon Dioxide ◽  
Nitrous Oxide ◽  
Mass Spectrometer ◽  
Isotope Ratio ◽  
High Performance ◽  
Atmospheric Gases ◽  
High Performing ◽  
Elemental Cycling ◽  
New Generation

<p>Biogenic gases carbon dioxide, methane and nitrous oxide are regularly analysed in many environments to understand elemental cycling and processes through the ecosphere. They are also of interest to atmospheric chemists for their role in climate change.  The Isoprime Tracegas has been key to a large amount of studies providing data on the isotopes of these key dynamic molecules. We shall review some of the notable publications and modifications in the field of atmospheric gas monitoring.</p><p>The development of the isoprime precisION mass spectrometer has permitted a new generation of control and automation of the mass spectrometer and integrated peripherals. This has greatly improved the accessibility and versatility of the instruments as a whole.</p><p>Taking advantage of the inherent benefits of the isoprime precisION the iso FLOW GHG has been developed for high performance analysis of CO2, N2O and CH4 and has the capacity to be rapidly customised for specific needs with options for N2 and N2O, Hydrogen isotopes in CH4 and denitrifier analysis.</p>

Biogeochemistry of Estuaries

2006 ◽  
Author(s):  
Thomas S. Bianchi
Keyword(s):  
Interdisciplinary Approach ◽  
Extensive Literature ◽  
Anthropogenic Inputs ◽  
Current State ◽  
Elemental Cycling ◽  
Advanced Students ◽  
Estuarine Management ◽  
Literature Base ◽  
Productive Systems ◽  
First Time

Biogeochemistry of Estuaries offers a comprehensive and interdisciplinary approach to understanding biogeochemical cycling in estuaries. Designed as a text for intermediate to advanced students, this book utilizes numerous illustrations and an extensive literature base to impart the current state-of-the-art knowledge in this field. While many of the existing books in estuarine science are comprised of edited volumes, typically focused on highly specific topics in estuaries,Biogeochemistry of Estuaries provides, for the first time, a unique foundation in the areas of geomorphology, geochemistry, biochemistry, aqueous chemistry, and ecology, while making strong linkages (trhoughout the text) to ecosystem-based processes in estuarine sciences. Estuaries, located at the interface between land and the coastal ocean are dynamic, highly productive systems that, in many cases, have been historically associated with development of many of the great centers of early human civilization. Consequentially, these systems have and continue to be highly impacted by anthropogenic inputs. This timely book takes the foundational basis of elemental cycling in estuarine and applies it to estuarine management issues. Biogeochemistry of Estuaries will be welcomed by estuarine/marine scientists, ecologists, biogeochemists, and environmentalists around the world.

Sign in / Sign up

Export Citation Format

Share Document