Preprints
Filtering by Subject: Soil Science
Scaling High-resolution Soil Organic Matter Composition to Improve Predictions of Potential Soil Respiration Across the Continental United States
Published: 2024-02-13
Subjects: Biogeochemistry, Soil Science
Despite the importance of microbial respiration of soil organic matter (SOM) in regulating carbon flux between soils and the atmosphere, soil carbon (C) cycling models remain primarily based on climate and soil properties, leading to large uncertainty in their predictions. Molecular data have long been proposed as a promising avenue for resolving modeling errors, but evidence for improved [...]
Aggregates versus pores? A survey among soil scientists about their perspectives on soil structure
Published: 2024-02-08
Subjects: Soil Science
Despite mostly uniform definitions of soil structure, two perspectives on it have been juxtaposed in the past: the “aggregate perspective” and the “pore perspective”. The debate as represented in the literature appears to be polarised. To test whether this is also the case in the wider soil science community, an online survey was conducted asking about soil scientists’ view on these perspectives. [...]
Microbial indicators and detection of Cu-sulfide ore mineralization
Published: 2024-01-02
Subjects: Biogeochemistry, Earth Sciences, Geochemistry, Geology, Other Earth Sciences, Physical Sciences and Mathematics, Soil Science
Rapid electrification of society is placing unprecedented demand on critical mineral and metal resources. New strategies and technologies are thus needed to promote mineral discovery in regions where deposits are likely buried deep under soil and glacial till. We show that microbial communities from different soil types change in composition in response to amendment with copper. We also show [...]
High Accuracy Estimation and Validation of InSAR-derived Surface Displacements at Temperate Raised Peatlands
Published: 2023-09-04
Subjects: Geophysics and Seismology, Hydrology, Soil Science
Peatland surface motion derived from satellite-based Interferometry of Synthetic Aperture Radar (InSAR) is potentially a proxy for groundwater level variations and greenhouse gas emissions from peat soils. Ground validation of these motions at equivalent temporal resolution and accuracy has proven problematic because of limitations of traditional surveying methods. Since 2019, peat surface motion [...]
Beyond microbial carbon use efficiency
Published: 2023-08-16
Subjects: Biogeochemistry, Earth Sciences, Environmental Microbiology and Microbial Ecology Life Sciences, Life Sciences, Physical Sciences and Mathematics, Soil Science
Microbial carbon use efficiency (CUE) is defined as the proportion of microbial biomass growth C versus substrate C uptake, and thus provides a useful measure of microbially driven accumulation and loss of soil organic carbon (SOC) 1. In a recent study published in Nature 2, the authors use a data-driven machine learning approach to conclude that CUE promotes global SOC storage based on a [...]
Eocene (50-55 Ma) greenhouse climate recorded in nonmarine rocks of San Diego, CA, USA
Published: 2023-08-08
Subjects: Chemistry, Climate, Earth Sciences, Geochemistry, Geology, Physical Sciences and Mathematics, Soil Science, Stratigraphy
Nonmarine rocks in sea cliffs of southern California store a detailed record of weathering under tropical conditions millions of years ago, where today the climate is much drier and cooler. This work examines early Eocene (~50-55 million-year-old) deeply weathered paleosols (ancient, buried soils) exposed in marine terraces of northern San Diego County, California, and uses their geochemistry and [...]
Estimating the silica content and loss-on-ignition in the North American Soil Geochemical Landscapes datasets: a recursive inversion approach
Published: 2023-07-28
Subjects: Geochemistry, Natural Resources and Conservation, Soil Science
A novel method of estimating the silica (SiO2) and loss-on-ignition (LOI) concentrations for the North American Soil Geochemical Landscapes (NASGL) project datasets is proposed. Combining the precision of the geochemical determinations with the completeness of the mineralogical NASGL data, we suggest a ‘reverse normative’ or inversion approach to calculate first the minimum SiO2, water (H2O) and [...]
Soil geochemistry of hydrogen and other gases along the San Andreas Fault
Published: 2023-07-23
Subjects: Environmental Chemistry, Geochemistry, Geology, Multivariate Analysis, Oil, Gas, and Energy, Soil Science
Natural hydrogen has generated great interest as a potential clean and renewable energy source. To understand the occurrence of natural hydrogen, 103 1-m deep soil gas samples were acquired near the San Andreas Fault at Jasper Ridge and Portola Valley, California, USA. The gas samples were analyzed for hydrogen, helium, carbon dioxide, light hydrocarbons, and fixed gas concentrations. Statistical [...]
An Artificial Neural Network to Estimate the Foliar and Ground Cover Input Variables of the Rangeland Hydrology and Erosion Model
Published: 2023-07-12
Subjects: Artificial Intelligence and Robotics, Environmental Monitoring, Hydrology, Natural Resources and Conservation, Natural Resources Management and Policy, Soil Science
Models like the Rangeland Hydrology and Erosion Model (RHEM) are useful for estimating soil erosion, however, they rely on input parameters that are sometimes difficult or expensive to measure. Specifically, RHEM requires information about foliar and ground cover fractions that generally must be measured in situ, which makes it difficult to use models like RHEM to produce erosion or soil risk [...]
Functional organic matter components in mangrove soils revealed by density fractionation
Published: 2023-07-04
Subjects: Biogeochemistry, Geochemistry, Soil Science
The mechanisms underlying stabilization of soil organic matter (SOM) in coastal ecosystems, including mangrove forests, are poorly understood, limiting our ability to predict the consequences of disturbances. Here, we introduce density fractionation to mangrove soils to identify the distribution and properties of the functional components of SOM with regard to degradation state, stability, and [...]
A Climate Counternarrative: Dubious Carbon Accounting is Making a Canopy Problem Look Like an Energy Problem (for Consent and Profit)
Published: 2023-05-12
Subjects: Agriculture, Climate, Forest Sciences, Soil Science
The modern rise in atmospheric carbon dioxide is man-made but driven by land stewardship changes rather than industrial activities like fossil fuels. Carbon cycle research fails to adequately convey surface-level interactions like plants soaking up carbon dioxide emitted near them. Clear-cutting a forest, for instance, produces a large plume of biogenic carbon dioxide that wind can carry away, [...]
Revisiting the Climate Narrative
Published: 2023-04-06
Subjects: Agriculture, Climate, Ecology and Evolutionary Biology, Environmental Engineering, Environmental Studies, Food Science, Forest Management, Hydrology, Natural Resources and Conservation, Natural Resources Management and Policy, Oil, Gas, and Energy, Other Environmental Sciences, Soil Science, Sustainability, Water Resource Management
The rise in atmospheric carbon dioxide is chiefly tied to land stewardship. Farmers and loggers have removed the plants that, until the industrial era, kept the soil fungi alive, kept soil emissions nearby by breaking the wind, and soaked those up. The result is plumes of carbon dioxide. Putting plants back in would curb these emissions. Farmers and loggers could address biodiversity loss [...]
From ground motion simulations to landslide occurrence prediction
Published: 2023-01-17
Subjects: Applied Statistics, Earth Sciences, Geomorphology, Geophysics and Seismology, Physical Sciences and Mathematics, Soil Science, Statistical Models, Statistics and Probability
Ground motion simulations solve wave equations in space and time, thus producing detailed estimates of the shaking time series. This is essentially uncharted territory for geomorphologists, for we have yet to understand which ground motion (synthetic or not) parameter, or combination of parameters, is more suitable to explain the coseismic landslide distribution. To address this gap, we developed [...]
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 [...]
Geochemical mapping by unmixing alluvial sediments: An example from northern Australia
Published: 2022-10-01
Subjects: Earth Sciences, Environmental Monitoring, Environmental Sciences, Geochemistry, Geomorphology, Natural Resource Economics, Sedimentology, Soil Science, Water Resource Management
Alluvial sediments have long been used in geochemical surveys as their compositions are assumed to be representative of areas upstream. Overbank and floodplain sediments, in particular, are increasingly used for regional to continental-scale geochemical mapping. However, during downstream transport, sediments from heterogeneous source regions are carried away from their source regions and mixed. [...]