Preprints
Filtering by Subject: Biogeochemistry
Rewetting drained boreal peatland forests does not mitigate climate warming in the 21st century
Published: 2025-02-08
Subjects: Biochemistry, Biophysics, and Structural Biology, Biogeochemistry, Forest Sciences, Natural Resources and Conservation, Natural Resources Management and Policy, Sustainability
Rewetting of drained peatland forests restores ecosystem functions and improves peatland ecological status. It is also considered to mitigate climate change, yet some studies challenge this view Recently, Laine et al. (2024, Restoration Ecology, 32(7), p.e14213) considered feasible restoration outcomes of boreal forestry drained peatlands and proposed that rewetting nutrient-rich peatland forests [...]
Glacially enhanced silicate weathering revealed by Holocene lake records
Published: 2025-02-08
Subjects: Biogeochemistry, Earth Sciences, Geochemistry, Physical Sciences and Mathematics
How glaciation affects CO2 drawdown by chemical weathering sets the strength of the weathering-climate feedback, which controls the exogenic carbon cycle and planetary habitability (Kump et al., 2000). However, the exact role of glaciers remains elusive as glaciation alters multiple factors controlling weathering, the net effect of which is ambiguous even in directionality. While illustrative, [...]
Challenges in Integrating DOM Chemodiversity into Kinetic Models of Soil Respiration for Improved Carbon Cycling Predictions
Published: 2025-01-25
Subjects: Biogeochemistry, Soil Science
Chemodiversity of dissolved organic matter (DOM) has been proposed as an ecosystem property controlling the microbial metabolism; thus, the fate of carbon (C) in soils. Recent research suggests that accounting for DOM chemodiversity can improve the accuracy of process-based C cycling models; however, this approach has never been validated at continental U.S. scale. In this study, we used [...]
A bipolar convection seesaw explains Earth system response to Heinrich events
Published: 2025-01-25
Subjects: Biogeochemistry, Climate, Oceanography
GelCam: Visualizing Episodic Sinking Particle Flux via a Polyacrylamide Gel-Based Sediment Trap
Published: 2025-01-11
Subjects: Biogeochemistry, Earth Sciences, Oceanography
While particle-intercepting traps remain a dominant method for quantifying the contribution of sinking particles to the biological carbon pump, fluxes are typically integrated over days to months. Observations of time-varying particle flux over shorter durations are very limited. To this end, we prototyped a camera system called “GelCam” which captures a rapid time-lapse image sequence of [...]
Origin and fate of methane in the Central American convergent margin
Published: 2025-01-11
Subjects: Biogeochemistry, Environmental Microbiology and Microbial Ecology Life Sciences, Volcanology
Convergent margins are gateways to Earth’s interior where volatile species are cycled between the planet's surface and interior. At these locations, carbon is recycled from deep reservoirs in two main forms: oxidized carbon, such as carbon dioxide, and reduced carbon, such as methane. While the former is quantitatively more important and its volcanic fluxes have been better constrained, the [...]
Hydrogenotrophic metabolisms in the subsurface and their implications for underground hydrogen storage and natural hydrogen prospecting
Published: 2025-01-09
Subjects: Biogeochemistry, Earth Sciences, Environmental Microbiology and Microbial Ecology Life Sciences, Oil, Gas, and Energy
Hydrogen is a fundamental electron donor in diverse microbial metabolisms and it is considered the energetic currency exchanged within microbial communities in anaerobic environments. Hydrogen is also the major actor in the transition to alternative low-carbon energy sources, primarily due to its dual role as energy source and energy carrier and to the production of water as a byproduct of its [...]
Preliminary Development of Machine Learning Emulators for Long-Term Atmospheric CO2 Evolution
Published: 2024-12-22
Subjects: Atmospheric Sciences, Biogeochemistry, Climate, Environmental Chemistry, Physical Sciences and Mathematics
This study evaluates machine learning emulators for modeling long-term atmospheric CO2 evolution by comparing Random Forests (RF) and Multilayer Perceptrons (MLP) in replicating cGENIE Earth System Model outputs over a one-million-year timescale. Using one-year pulse emission experiments spanning 1,000-20,000 PgC with outputs tracked for 106 years, we assessed emulator performance across multiple [...]
On the assessment of sinking particle fluxes from in situ particle size distributions
Published: 2024-12-17
Subjects: Biogeochemistry, Earth Sciences, Other Earth Sciences
The biological carbon pump plays a crucial role in the global carbon cycle, particularly through sinking particles carrying carbon to deep waters. The Underwater Vision Profilers (UVP) is widely used for studying particle properties. UVP-based particulate organic carbon (POC) flux is typically derived from particle size distributions (PSDs) assuming size dependent sinking rates and carbon [...]
Towards statistical modeling of chlorophyll-a concentrations in Balikpapan Bay, Indonesia: Implications for algal bloom detection
Published: 2024-10-26
Subjects: Artificial Intelligence and Robotics, Biogeochemistry, Environmental Monitoring, Marine Biology, Oceanography
This study presents a comprehensive statistical analysis of chlorophyll-a dynamics in Balikpapan Bay, Indonesia, combining time series analysis, extreme value modeling, and machine learning techniques to understand phytoplankton variability near Indonesia's planned new capital city. Analysis of daily chlorophyll-a concentrations (2019-2021) revealed a non-Gaussian distribution (skewness = 2.212, [...]
Potential effects of coagulation processes on phytoplankton mortality in the Elbe estuary from a Lagrangian point of view
Published: 2024-10-17
Subjects: Biogeochemistry, Environmental Health and Protection, Environmental Indicators and Impact Assessment, Environmental Monitoring, Oceanography, Water Resource Management
Within the Elbe estuary, a sudden change in depth occurs when the river enters the shipping channel in the Port of Hamburg. This change in depth correlates with a sharp decline in phytoplankton concentrations. This decline affects the estuarine food web and shifts the ecosystem from autotrophic to heterotrophic during the summer months. Previous studies have hypothesized that this collapse is [...]
Instability in the geological regulation of Earth’s climate
Published: 2024-10-06
Subjects: Biogeochemistry
Negative feedback between climate and atmospheric CO2, as mediated via weathering of silicate minerals, is thought to provide the dominant regulation of Earth’s climate on geological timescales. In contrast, we show here that faster feedbacks involving organic matter are critical and create unexpected instability in the system. Specifically, using an Earth system model, we show how organic carbon [...]
Prioritizing Safety, Advancing Efficiency: Developing a New Total Phosphorous Microwave Digestion Method for Sediment Core Nutrient Analysis
Published: 2024-09-27
Subjects: Biogeochemistry, Environmental Chemistry, Inorganic Chemistry, Soil Science
Long-term datasets are invaluable resources for understanding broad-level temporal patterns in ecosystems. For over two decades, UC Davis and Lake County Water Resources Department have collaborated on a long-term monitoring project of Clear Lake sediment nutrient concentrations, in an effort to better understand nutrient cycling in Clear Lake. When the need for a new total phosphorus digestion [...]
Contributions to the discussion of novel detection of dark oxygen production at the abyssal seafloor
Published: 2024-09-19
Subjects: Biogeochemistry, Earth Sciences
There is an overwhelming consensus between researchers based on a vast body of peer-reviewed literature that deep sea ecosystems constitute an oxygen sink. Specific studies on abyssal seafloor regions that contain polymetallic nodules have also confirmed this result. In contrast to this well-founded and longstanding paradigm, Sweetman et al. claim to provide evidence to support a hypothesis that [...]
Carbon storage in Northern Ireland’s aquatic ecosystems: an evidence synthesis to support policy development.
Published: 2024-09-06
Subjects: Biogeochemistry, Marine Biology, Oceanography
Blue carbon is defined as carbon that is naturally sequestered and stored in the world’s aquatic ecosystems. Governments around the world are currently seeking to develop a range of tools to help meet their commitments to reduce greenhouse gas emissions and potentially reverse anthropogenic climate change. As such, there is growing interest from policy makers in natural processes which may be [...]