Preprints
Filtering by Subject: Biogeochemistry
No support for carbon storage of >1000 GtC in northern peatlands
Published: 2019-12-04
Subjects: Biogeochemistry, Earth Sciences, Physical Sciences and Mathematics
Northern peatlands store large amounts of carbon (C) and have played an important role in the global carbon cycle since the Last Glacial Maximum. Most northern peatlands have established since the end of the deglaciation and accumulated C over the Holocene, leading to a total present-day stock of 500 ± 100 GtC. This is a consolidated estimate, emerging from a diversity of methods. Recently, [...]
Simultaneous measurement of aqueous redox sensitive elements and their species across soil-water interface
Published: 2019-11-20
Subjects: Biogeochemistry, Earth Sciences, Environmental Monitoring, Environmental Sciences, Physical Sciences and Mathematics
Soil-water interface (SWI) hosts versatile elements speciation and controls elements cycling in flooded lands. However, the study on the element’s interaction along SWI is limited by the sampling and analytical methods available. Here with an optimized ICP-MS method and an updated porewater sampler, we succeeded in simultaneously mapping the elements of environmental concerns in every 1.7 mm [...]
Macrophyte cover type and groundwater as the key drivers of the extremely high organic carbon concentration of soda pans
Published: 2019-11-20
Subjects: Biogeochemistry, Earth Sciences, Environmental Sciences, Other Environmental Sciences, Physical Sciences and Mathematics
1. Endorheic soda pans are among the aquatic systems that have the highest dissolved organic carbon (DOC) content on the planet with concentrations reaching values close to 1 g L−1. Considering the importance of inland waters in the global carbon cycle, the understanding of the drivers of such outstanding aquatic organic carbon pools is eminent. The soda pans of the Carpathian Basin present a [...]
Equifinality, Sloppiness, and emergent model structures of mechanistic soil biogeochemical models
Published: 2019-11-05
Subjects: Biogeochemistry, Earth Sciences, Environmental Sciences, Physical Sciences and Mathematics, Soil Science
Biogeochemical models increasingly consider the microbial control of car- bon cycling in soil. The major current challenge is to validate mechanistic descriptions of microbial processes and predicted system responses against experimental observations. We analyzed soil biochemical models of different complexity regarding parameter identifiability using information geometry, i.e. a model is [...]
A unique bacteriohopanetetrol stereoisomer of marine anammox
Published: 2019-10-31
Subjects: Biogeochemistry, Earth Sciences, Physical Sciences and Mathematics
Anaerobic ammonium oxidation (anammox) is a significant process for bioavailable nitrogen removal from marine systems. A bacteriohopanetetrol (BHT) isomer, with unknown stereochemistry, eluting later than BHT using high performance liquid chromatography (HPLC), was detected in ‘Ca. Scalindua profunda’ and proposed as a biomarker for anammox in marine paleo-environments. Four non-marine, [...]
On the difficulties of being rigorous in environmental geochemistry studies: some recommendations for designing an impactful paper
Published: 2019-10-25
Subjects: Biogeochemistry, Chemistry, Earth Sciences, Environmental Chemistry, Environmental Sciences, Geochemistry, Other Environmental Sciences, Physical Sciences and Mathematics
There have been numerous environmental geochemistry studies using chemical, geological, ecological and toxicological methods but each of these fields requires more subject specialist rigour than has generally been applied so far. Field-specific terminology has been misused and the resulting interpretations rendered inaccurate. In this paper, we propose a series of suggestions, based on our [...]
River inflow dominates methane emissions in an Arctic coastal system
Published: 2019-10-13
Subjects: Biogeochemistry, Earth Sciences, Environmental Monitoring, Environmental Sciences, Fresh Water Studies, Geochemistry, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Measurements of greenhouse gases in Arctic waters are strongly biased toward low-ice summer conditions, with few observations during periods of seasonal ice retreat. We present a year-round time series of dissolved methane (CH4) and nitrous oxide (N2O), along with targeted observations during ice melt of CH4 and carbon dioxide (CO2) in a river and estuary adjacent to Cambridge Bay, Nunavut, [...]
Skillful multiyear predictions of ocean acidification in the California Current System
Published: 2019-10-10
Subjects: Biogeochemistry, Climate, Earth Sciences, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
The California Current System (CCS) sustains economically valuable fisheries and is particularly vulnerable to ocean acidification, due to the natural upwelling of corrosive waters that affect ecosystem function. Marine resource managers in the CCS could benefit from advanced knowledge of ocean acidity on multiyear timescales. We use a novel suite of retrospective forecasts with an initialized [...]
Redox-informed models of global biogeochemical cycles
Published: 2019-10-07
Subjects: Biogeochemistry, Earth Sciences, Environmental Sciences, Physical Sciences and Mathematics
Microbial activity mediates the global flow of carbon, oxygen, nitrogen, and other elements, including climatically significant gases. However, non-photosynthetic microbial activity is typically not resolved dynamically or mechanistically in global models of the marine and terrestrial biospheres, inhibiting predictive capability. Understanding the global-scale impact of complex microbial [...]
Controls of River Dynamics on Residence Time and Biogeochemical Reactions of Hydrological Exchange Flows in A Regulated River Reach
Published: 2019-10-06
Subjects: Biogeochemistry, Earth Sciences, Hydrology, Physical Sciences and Mathematics
Residence Time Distributions (RTDs) exerts an important control on biogeochemical translations in watershed systems. RTDs tend to follow time-invariant exponential, lognormal, or heavy-tailed RTDs that have power-law behaviors for long tails in headwater or low-order streams. However, there is increasing recognition that RTDs can be more complicated and time-variable in response to dynamic [...]
Mercury loading within the Selenga River Basin and Lake Baikal, Siberia
Published: 2019-09-28
Subjects: Biogeochemistry, Earth Sciences, Environmental Sciences, Geochemistry, Physical Sciences and Mathematics
Mercury (Hg) loading in Lake Baikal, a UNESCO world heritage site, is growing and poses a serious health concern to the lake’s ecosystem due to the ability of Hg to transform into a toxic form, known as methylmercury (MeHg). Monitoring of Hg into Lake Baikal is spatially and temporally sparse, highlighting the need for insights into historic Hg loading. This study reports measurements of Hg [...]
What Fractionates Oxygen Isotopes During Respiration? Insights from Multiple Isotopologues and Theory
Published: 2019-08-21
Subjects: Biogeochemistry, Earth Sciences, Physical Sciences and Mathematics
The precise mass dependence of respiratory O2 consumption underpins the “oxygen triple-isotope” approach to quantifying gross primary productivity in modern and ancient environments. Yet, the physical-chemical origins of the key 18O/16O and 17O/16O covariations observed during respiration have not been tied to theory; thus the approach remains empirical. First-principles calculations on enzyme [...]
Vertical Eddy Iron Fluxes Support Primary Production in the Open Southern Ocean
Published: 2019-08-04
Subjects: Biogeochemistry, Earth Sciences, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
The primary productivity of the Southern Ocean ecosystem, and associated biological carbon pump, is limited by the availability of the micronutrient iron. Riverine sediments and atmospheric dust supply iron at the ocean margins, but in the vast open ocean, iron reaches phytoplankton primarily when iron-rich sub-surface waters enter the euphotic zone, linking vertical transport processes to [...]
Relationships between soil chemical properties and rare earth element concentrations in the aboveground biomass of a tropical herbaceous plant
Published: 2019-07-18
Subjects: Biogeochemistry, Earth Sciences, Geochemistry, Physical Sciences and Mathematics
The geochemical behavior of rare earth elements (REE) has been mainly investigated in geological systems where they represent the best proxies for processes occurring at the interface between different media. REE concentrations, normalized with respect to the upper continental crust, were used to assess their behavior. In this study, REE geochemical behavior was investigated in plant shoots of a [...]
The Baltic TRANSCOAST approach – investigating shallow coasts as terrestrial-marine interface of water and matter fluxes
Published: 2019-07-16
Subjects: Biogeochemistry, Biology, Earth Sciences, Environmental Monitoring, Environmental Sciences, Hydrology, Life Sciences, Marine Biology, Oceanography and Atmospheric Sciences and Meteorology, Other Oceanography and Atmospheric Sciences and Meteorology, Other Plant Sciences, Physical Sciences and Mathematics, Plant Sciences, Soil Science
In Baltic TRANSCOAST we study the physical, biogeochemical, and biological processes at the land-ocean interface. The coastal zone is heavily impacted by various human activities as well as by geomorphological and climatic processes – on both the land and the sea side. Land-sea interactions at low lying coastal areas that are often dominated by peatlands, and are a common feature along the Baltic [...]