Preprints
Filtering by Subject: Biogeochemistry
Multi-proxy assessment of surface sediments using APPI-P FTICR-MS reveals a complex biogeochemical record along a salinity gradient in the Pearl River estuary and coastal South China Sea
Published: 2021-12-10
Subjects: Analytical Chemistry, Biogeochemistry, Chemistry, Earth Sciences, Environmental Chemistry, Environmental Monitoring, Environmental Sciences, Geochemistry, Physical Sciences and Mathematics
The Pearl River drains the second largest watershed in China, funnelling large amounts of freshwater and organic matter into the northern part of the South China Sea through an estuary characterized by pronounced biogeochemical gradients. In this study we analyzed organic extracts of surface sediments collected along land-sea transect that captures a transition from freshwater environment at the [...]
Continuous cultivation of the lithoautotrophic nitrate-reducing Fe(II)-oxidizing culture KS in a chemostat bioreactor
Published: 2021-12-07
Subjects: Biogeochemistry
Laboratory-based studies on microbial Fe(II) oxidation are commonly performed over just a few weeks in small volumes with high substrate concentrations, resulting in geochemical gradients and volumetric effects caused by sampling. We used a chemostat to enable uninterrupted supply of medium, and investigated autotrophic growth of the nitrate-reducing Fe(II)-oxidizing culture KS for 24 days. We [...]
Methane Fluxes of Vegetated Areas in Natural Freshwater Ecosystems: Assessments and Global Significance
Published: 2021-12-05
Subjects: Biogeochemistry, Earth Sciences, Environmental Sciences, Other Environmental Sciences
Freshwater ecosystems, including wetlands, lakes, and running waters, are estimated to contribute roughly 40% to global emissions of methane (CH4), a highly potent greenhouse gas. The emission of CH4 to the atmosphere entails the diffusive, ebullitive, and plant-mediated pathway. The latter, in particular, has been largely understudied and is neither well understood nor quantified. We have [...]
Estuarine-deltaic controls on coastal carbon burial in the western Ganges-Brahmaputra delta over the last 5,000 years
Published: 2021-11-26
Subjects: Applied Statistics, Biogeochemistry, Earth Sciences, Environmental Sciences, Geochemistry, Geology, Geomorphology, Other Earth Sciences, Other Environmental Sciences, Other Statistics and Probability, Physical Sciences and Mathematics, Sedimentology, Statistical Methodology, Statistical Models, Statistics and Probability, Water Resource Management
The Ganges–Brahmaputra fluvial system drains the Himalayas and is one of the largest sources of terrestrial biosphere carbon to the ocean. It represents a major continental reservoir of CO2 associated with c. 1–2 billion tons of sediment transported each year. Shallow coastal environments receive substantial inputs of terrestrial carbon (900 Tg C yr−1), with allochthonous carbon capture on [...]
Stable Silicon Isotopes Uncover a Mineralogical Control on the Benthic Silicon Cycle in the Arctic Barents Sea
Published: 2021-11-12
Subjects: Biogeochemistry, Earth Sciences, Geochemistry, Physical Sciences and Mathematics, Soil Science
Biogeochemical cycling of silicon (Si) in the Barents Sea is under considerable pressure from physical and chemical changes, including dramatic warming and sea ice retreat, together with a decline in dissolved silicic acid (DSi) concentrations of Atlantic inflow waters since 1990. Moreover, further expansion of the Atlantic realm (termed ‘Atlantification’) is expected to shift phytoplankton [...]
Open access in geochemistry from preprints to data sharing: past, present and future
Published: 2021-11-08
Subjects: Biogeochemistry, Cosmochemistry, Earth Sciences, Geochemistry, Volcanology
In this short communication, we discuss the latest advances regarding Open Access in the Earth Sciences and geochemistry community from preprints to findable, accessible, interoperable and reusable data following 14f session held at Goldschmidt conference (4-9 July 2021) dedicated to “Open Access in Earth Sciences”.
Airborne laser scanning proxies of canopy light transmission in forests
Published: 2021-10-29
Subjects: Biodiversity, Biogeochemistry, Computer Sciences, Earth Sciences, Ecology and Evolutionary Biology, Environmental Sciences, Forest Sciences, Life Sciences, Physical Sciences and Mathematics, Plant Sciences, Software Engineering, Statistics and Probability
Reliable estimates of canopy light transmission are critical to understanding the structure and function of vegetation communities but are difficult and costly to attain by traditional field inventory methods. Airborne laser scanning (ALS) data uniquely provide multi-angular vertically resolved representation of canopy geometry across large geographic areas. While previous studies have proposed [...]
Bridging knowledge gaps with hybrid machine-learning forest ecosystem models (ML-FEMs): inferential simulation of past understory light regimes
Published: 2021-10-29
Subjects: Artificial Intelligence and Robotics, Biodiversity, Biogeochemistry, Computer Sciences, Earth Sciences, Ecology and Evolutionary Biology, Forest Sciences, Life Sciences, Physical Sciences and Mathematics, Plant Sciences
Soil moisture is a key limiting factor of plant productivity in boreal and montane regions, producing additional climate feedbacks through evaporation, regeneration, mortality, and respiration. Understory solar irradiation – the primary driver of surface temperature and evaporative demand – remains poorly represented in vegetation models due to a lack of 3-D canopy geometry. Existing models are [...]
Simulated decline of a northern forest due to anthropogenic controls on the regeneration-mortality balance
Published: 2021-10-29
Subjects: Biodiversity, Biogeochemistry, Earth Sciences, Ecology and Evolutionary Biology, Environmental Sciences, Forest Sciences, Life Sciences, Physical Sciences and Mathematics, Plant Sciences
The population structure of forests is shaped by balancing the opposing forces of regeneration and mortality, each of which influence C turnover rates and are sensitive to climate. Regeneration underlies the migrational potential of forests to climatic change and remains underserved in modeling studies. Our objective was to test the hypothesis that warming may reduce tree regeneration rates while [...]
Emergence of anthropogenic fire regimes in the southern boreal of Canada
Published: 2021-10-29
Subjects: Biogeochemistry, Earth Sciences, Ecology and Evolutionary Biology, Environmental Sciences, Forest Sciences, Life Sciences, Plant Sciences
While radiative forcing and thus land surface temperatures have been shown to positively correlate with fire severity, precipitation, and lightning strike frequency, the effects of human activity on fire regimes remain difficult to disentangle from geophysical drivers given co-variation between these factors. Here, I analyze fire regimes in the 1919-2012 period across Canada and compare national [...]
A 18,000 yr record of tropical land temperature, convective activity and rainfall seasonality from the maritime continent
Published: 2021-10-27
Subjects: Biogeochemistry, Climate, Earth Sciences, Geology, Physical Sciences and Mathematics, Planetary Hydrology
The maritime continent exports an enormous amount of heat and moisture to the rest of the globe via deep atmospheric convection. How this export has changed through time during the last deglacial period and through the Holocene, is hardly known yet critical for the understanding of global climate dynamics. Here we present a continuous paleoclimate record from southern Thailand covering the last [...]
Reproducibility in subsurface geoscience
Published: 2021-10-26
Subjects: Biogeochemistry, Cosmochemistry, Earth Sciences, Environmental Education, Environmental Health and Protection, Environmental Indicators and Impact Assessment, Environmental Monitoring, Environmental Sciences, Geochemistry, Geology, Geomorphology, Geophysics and Seismology, Glaciology, Hydrology, Mineral Physics, Natural Resource Economics, Natural Resources and Conservation, Natural Resources Management and Policy, Oil, Gas, and Energy, Other Earth Sciences, Other Environmental Sciences, Paleobiology, Paleontology, Sedimentology, Soil Science, Speleology, Stratigraphy, Sustainability, Tectonics and Structure, Volcanology, Water Resource Management
Reproducibility, the extent to which consistent results are obtained when an experiment or study is repeated, sits at the foundation of science. The aim of this process is to produce robust findings and knowledge, with reproducibility being the screening tool to benchmark how well we are implementing the scientific method. However, the re-examination of results from many disciplines has caused [...]
Consistent Controls on Trace Metal Micronutrient Speciation in Wetland Soils and Stream Sediments
Published: 2021-10-15
Subjects: Biogeochemistry, Geochemistry, Soil Science
Trace metal are essential for microbially-mediated biogeochemical processes occurring in anoxic wetland soils and stream bed sediments, but low availability of these elements may inhibit anaerobic element cycling and transformations. Solid-phase speciation is likely a critical control on trace metal availability but has seen limited study in anoxic systems having concentrations similar to [...]
The ‘europium anomaly’ in plants: facts and fiction
Published: 2021-09-08
Subjects: Biogeochemistry, Earth Sciences, Geochemistry, Life Sciences, Plant Sciences
Aims Rare earth elements (REEs) and normalized REE patterns determined in plant and soil samples represent powerful tools to trace biogeochemical processes during weathering, soil genesis and processes in the rhizosphere, and thus publications reporting rare earth elements and normalized REE patterns in soil systems and plants are rapidly increasing. Methods A normalized REE pattern allows [...]
Safety and Belonging in the Field: A Checklist for Educators
Published: 2021-08-19
Subjects: Atmospheric Sciences, Biogeochemistry, Climate, Cosmochemistry, Earth Sciences, Education, Environmental Education, Environmental Health and Protection, Environmental Indicators and Impact Assessment, Environmental Monitoring, Environmental Sciences, Environmental Studies, Fresh Water Studies, Geochemistry, Geographic Information Sciences, Geography, Geology, Geomorphology, Geophysics and Seismology, Glaciology, Higher Education, Human Geography, Hydrology, Life Sciences, Meteorology, Mineral Physics, Natural Resource Economics, Natural Resources and Conservation, Natural Resources Management and Policy, Nature and Society Relations, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Oil, Gas, and Energy, Other Earth Sciences, Other Environmental Sciences, Other Geography, Other Oceanography and Atmospheric Sciences and Meteorology, Other Planetary Sciences, Outdoor Education, Paleobiology, Paleontology, Physical and Environmental Geography, Physical Sciences and Mathematics, Planetary Biogeochemistry, Planetary Geochemistry, Planetary Geology, Planetary Geomorphology, Planetary Geophysics and Seismology, Planetary Glaciology, Planetary Hydrology, Planetary Mineral Physics, Planetary Sciences, Planetary Sedimentology, Remote Sensing, Sedimentology, Social and Behavioral Sciences, Soil Science, Spatial Science, Speleology, Stratigraphy, Sustainability, Tectonics and Structure, Volcanology, Water Resource Management
Ensuring taught fieldwork is a positive, generative, collective, and valuable experience for all participants requires considerations beyond course content. To guarantee safety and belonging, participants’ identities (backgrounds and protected characteristics) must be considered as a part of fieldwork planning and implementation. Furthermore, getting fieldwork right is an important step in [...]