Preprints
Filtering by Subject: Biogeochemistry
Bioavailable Sr and Pb isotope ratios of archaeological cattle bone from coastal India
Published: 2023-04-28
Subjects: Biogeochemistry, Geochemistry
We present the first measurement of bioavailable strontium (87Sr/86Sr) and lead (206Pb/204Pb, 207Pb/204Pb, and 208Pb/204Pb) isotope ratios from five cattle bones and one soil sample from Erenda, a chalcolithic site in coastal east India. Bioavailable 87Sr/86Sr of bones differ from that of the soil. A similar Pb isotope ratio of bones to the soil indicates an insignificant diagenesis and local [...]
Radiocarbon analysis of soil microbial biomass via direct chloroform extraction
Published: 2023-04-15
Subjects: Biogeochemistry
Microbial processing of soil organic matter is a significant driver of C cycling, yet we lack an understanding of what shapes the turnover of this large terrestrial pool. In part, this is due to limited options for accurately identifying the source of C assimilated by microbial communities. Laboratory incubations are the most common method for this; however, they can introduce artifacts due to [...]
Extrapolation-based regionalized re-evaluation of the global estuarine surface area
Published: 2023-02-24
Subjects: Biogeochemistry, Earth Sciences, Geomorphology, Hydrology
At the interface between the continental and oceanic domains, estuaries are essential components of the land–ocean aquatic continuum. These coastal ecosystems play a significant role in biogeochemical cycles, as they transform and export large amounts of terrigenous carbon and nutrients from rivers to marine waters. Because of this intense biogeochemical processing, they are significant [...]
Deforestation as an anthropogenic driver of mercury pollution
Published: 2023-01-24
Subjects: Atmospheric Sciences, Biogeochemistry, Earth Sciences, Environmental Sciences
Deforestation reduces the capacity of the terrestrial biosphere to take up the toxic pollutant mercury (Hg) and enhances the release of secondary Hg from soils. The consequences of deforestation for Hg cycling are not currently considered by anthropogenic emissions inventories or specifically addressed under the global Minamata Convention on Mercury. Using global Hg modeling constrained by field [...]
Are marl-limestone alternations mainly driven by CaCO3 variations at the astronomical timescale? New insights from extraterrestrial 3He
Published: 2023-01-07
Subjects: Biogeochemistry, Earth Sciences, Geochemistry, Geology, Sedimentology, Stratigraphy
Marl-limestone alternations are rhythmical inter-bedded deposits that commonly occur in many sedimentological environments. It is quite well established that these lithological variations originate from astronomically-driven climatic variations paced by the Milankovitch cycles of main periods 19, 23, 41, 100 and 405 ka. However, the sedimentological mechanisms involved are not clear: some models [...]
Tracing timing of growth in cultured mollusks using strontium spiking
Published: 2022-12-23
Subjects: Aquaculture and Fisheries Life Sciences, Biogeochemistry, Geochemistry, Paleontology
Growth experiments present a powerful tool for determining the effect of environmental parameters on growth and carbonate composition in biogenic calcifiers. For successful proxy calibration and biomineralization studies, it is vital to exactly identify volumes of carbonate precipitated at precise intervals during the experiment. Here, we investigate the use of strontium labelling in mollusk [...]
Oxidation Rates and Redox Stabilization of Ferrous Iron in Trioctahedral Smectites
Published: 2022-12-16
Subjects: Biogeochemistry, Geochemistry, Other Earth Sciences, Planetary Biogeochemistry, Planetary Geochemistry
Iron(II)-bearing trioctahedral smectites (saponites) form during anoxic alteration of basaltic rock. They are predicted to have been widespread on the early Earth and are observed in the oceanic subsurface today. Smectite structures, including the occupancy of sites in the octahedral sheet, affect iron redox behavior but the rates and products of trioctahedral smectite oxidation have been largely [...]
Geosphere and Biosphere coevolution: the role of trace metals availability in the evolution of biogeochemistry
Published: 2022-11-21
Subjects: Biochemistry, Biophysics, and Structural Biology, Biogeochemistry, Earth Sciences, Ecology and Evolutionary Biology, Microbiology, Planetary Sciences
Earth’s geosphere and biosphere have coevolved over time, influencing each other’s stability and keeping our planet habitable for most of its 4.543 billion years of history. Biogeochemical cycles play a key role in controlling this interaction, connecting long-term geological cycles and the much faster evolution of the Earth’s outer biologically dominated envelopes. A small set of [...]
Community recommendations for geochemical data, services and analytical capabilities in the 21st century
Published: 2022-11-17
Subjects: Biogeochemistry, Cosmochemistry, Earth Sciences, Geochemistry
The majority of geochemical and cosmochemical research is based upon observations and, in particular, upon the acquisition, processing and interpretation of analytical data from physical samples. The exponential increase in volumes and rates of data acquisition over the last century, combined with advances in instruments, analytical methods and an increasing variety of data types analysed, has [...]
Atmospheric carbon emissions from benthic trawling depend on water depth and ocean circulation
Published: 2022-10-28
Subjects: Biogeochemistry, Earth Sciences, Oceanography, Oceanography and Atmospheric Sciences and Meteorology
Through its vastness, resilience and biogeochemical complexity, the ocean offers humanity some of the largest potential natural pathways for removing carbon dioxide from the atmosphere while avoiding new sources of anthropogenic emissions. In proposing a network of new marine protected areas in service of global ocean conservation, Sala et al. describe a potentially large climate benefit of such [...]
Experimental comparisons of carbonate-associated sulfate extraction methods
Published: 2022-10-26
Subjects: Biogeochemistry, Earth Sciences, Geochemistry, Geology, Physical Sciences and Mathematics
Carbonate-associated sulfate (CAS) refers to trace amounts of sulfate incorporated into carbonate minerals during precipitation. CAS has been the most commonly used approach to recover the paleo-seawater sulfate sulfur isotope composition (δ34Ssw) as carbonate rocks are more common and occur in less restricted marine environments than alternative sulfate-bearing minerals (such as gypsum and [...]
Trait-based modeling revealed higher microbial diversity leads to greater ecological resilience in response to an ecosystem disturbance
Published: 2022-10-15
Subjects: Biogeochemistry, Earth Sciences, Environmental Microbiology and Microbial Ecology Life Sciences, Microbiology, Oceanography, Oil, Gas, and Energy, Physical Sciences and Mathematics, Sustainability, Terrestrial and Aquatic Ecology
To quantitatively understand the ecological resilience of an ecosystem with specialized habitats, we focused on deep-sea microbial communities and simulated the response of diverse microbes in specialized habitats to a pulse ecosystem disturbance - the Deepwater Horizon Oil Spill in the Gulf of Mexico. Two microbial communities with equivalent metabolic libraries were acclimated to the presence [...]
FIELD LEVEL VARIATION INFLUENCED OUTCOMES MORE THAN N-FERTILISER, FYM, COVER CROPS OR THEIR LEGACY EFFECTS FOLLOWING CONVERSION TO A NO-TILL ARABLE SYSTEM
Published: 2022-10-08
Subjects: Agriculture, Biogeochemistry, Earth Sciences, Environmental Chemistry, Other Earth Sciences, Other Environmental Sciences, Soil Science
Crop establishment in no-till arable systems benefits from favourable soil conditions. Combined with the incorporation of crop residues and manures, no-till can influence soil organic carbon (SOC) and organic matter (SOM) dynamics, crop productivity and nutrient cycling. These processes are shaped by spatial and temporal factors and associated microbial processes. There is a lack of diachronic [...]
Influence of macrophytes on stratification and dissolved oxygen dynamics in ponds
Published: 2022-09-24
Subjects: Biogeochemistry, Hydrology, Terrestrial and Aquatic Ecology
1. Small waterbodies are sensitive to stressors such as nutrient enrichment and heatwaves. However, when present, macrophytes may mediate these compounding stressors through their influence on water column thermal structure. Canopy-forming macrophyte beds can induce thermal stratification, which may limit the depth and degree of water column warming during heatwaves. 2. We leveraged an ecosystem [...]
Much of Zero Emissions Commitment Occurs Before Reaching Net Zero Emissions
Published: 2022-08-25
Subjects: Biogeochemistry, Climate, Earth Sciences, Environmental Sciences
We explore the response of the Earth’s climate and carbon system to an idealized sequential addition and removal of CO2 to the atmosphere, following a symmetric and continuous emissions pathway, in contrast to the discontinuous emissions pathways that have largely informed our understanding of the climate response to net-zero and net-negative emissions to date. We find, using both an Earth [...]