carbon limitation
Water acts as a limiting factor for both decomposition of organic matter and net carbon assimilation
carbon loss rate per degree per year
carbon oxidation
carbon spectroscopy
Spectroscopic techniques including NEXAFS and FTIR used to characterize the functional group composition and chemical structure of organic carbon
carbon use efficiency
The proportion of carbon taken up by microorganisms that is converted to biomass rather than respired as CO2
charge balance
chemical recalcitrance
chemical weathering proxy
Trace elements like rhenium that can be used to track and quantify specific weathering processes due to their distinctive geochemical behavior
chemodiversity
The number of molecular formulae detected in a sample
chloride
comammox
Complete ammonia-oxidizing bacteria capable of carrying out both ammonia oxidation to nitrite and nitrite oxidation to nitrate steps
compound classes
concentration contrasts
conifer needle decomposition
conservative mixing
Predictable linear mixing behavior of chemical constituents between two water sources without reaction or loss
dentrification
dilution of harmful secondary metabolites
disinfection byproducts
Chemical compounds formed when chlorine or other oxidants react with organic matter in water during drinking water treatment
disinfection byproducts
dissimilatory metal reduction
Microbial reduction of metal oxides and oxyhydroxides where metals serve as electron acceptors in anaerobic respiration
dissolved Al
dissolved As
dissolved Re yield
dissolved organic matter export control points
Areas where high rates of reactants are exported into receiving streams during hydrologic events
dissolved rhenium yields
diurnal biogeochemical cycling
Daily fluctuations in dissolved oxygen and iron concentrations driven by photosynthesis, respiration, and temperature changes
dormancy rate law
double bond equivalence
downgradient export
ecosystem function
The roles that invertebrates play in the flow of energy and cycling of nutrients in wetlands
elemental imbalance
end-member concentrations
enzymatic hydrolysis
evaporite deposition
Formation of chemical sedimentary rocks through evaporation of saline waters leading to precipitation of minerals like gypsum and halite
evasion
external inputs
extracellular oxidative enzymes
Enzymes produced by microorganisms that catalyze oxidation reactions outside the cell, including laccase, polyphenol oxidase, and peroxidase
extractable metals
Iron and manganese recovered by acid extraction, indicating metals available for microbial electron transport processes
feedback strength
Quantitative measure of the sensitivity of weathering rates to changes in atmospheric CO2, characterized by 1st and 2nd order components
feedbacks between mineralogy, weathering rates, soil production, bedrock nutrient availability, soil water-holding capacity, and ecosystem productivity
fermentative DNRA
ferrihydrite nanoparticles
Poorly crystalline Fe oxyhydroxide mineral nanoparticles that are typically the first solid Fe oxyhydroxide phase to form upon oxidation of dissolved ferrous iron
first-order kinetics
A simplified kinetic model where reaction rates are proportional to the concentration of a single reactant
fluorescence index
formaldehyde oxidation
formation potential
fraction of modern standard
functional group abundance
Quantitative measurement of the relative amounts of different organic functional groups (carbonyl, aliphatic, amide, quinonic, aromatic, phenolic, polysaccharide) in soil organic matter
geogenic nitrogen
Nitrogen derived from weathering of nitrogen-bearing geological formations such as marine shales