]> ontology to start modeling primary production measurements margaret 2014-11-13 NetPrimaryProductionCarbonFlux the amount of primary production available for export (ie, gross, minus losses, like the autotropys own respirateion, or other loss (exudation) not used by the carbon-fixing organism itself) = gross primary production - autotrophic respiration synonyms: NPP SoilCarbonPool Measurement CarbonFlux Carbon fluxes all have dimensions of mass or amount of Carbon per area (or volume) per time biochemically-oriented projects use moles (e.g., for Stiocheometry) Climate-oriented projects use kg PlanktonCarbonPool CarbonPool Carbon Pools are amounts of carbon in the system. diimensions are mass Carbon per area (eg, kg per m2 (can these be moles?) GrossPrimaryProductionCarbonFlux pprod before the autotrphs own respiration is subtracted. also called photosynthetic rate, or carbon fixation rate. Synonyms: GPP Method The methods that can be used for measurements. I don't think its the place of this ontology to model all the differences and assumptions between methods. Reasons: 1. That would get very complicated and is probably out of scope. 2. we should assume some level of knowledge of the user. People using pprod data should know enough to evaluate basic diifferences between methods. eg, an ecologist ought to know that "allometrics" are an average for a species or population, not a community. or an oceanographer ought to know the difference between light-dark O2 and light-dark C14 inclubations. So if you want "community NPP", and you see the method used was allometric -- you'd know you had to understand the community composition to know if prod of one or a few groups is enough. if you wanted "community NPP",in ocean data, you would know that O2 light-dark was OK, but that C14 update might actually be GPP PeakBiomassHarvestMethod EddyCovarianceMethod http://en.wikipedia.org/wiki/Eddy_covariance TotalLivingCarbonPool HeterotrophicRespirationCarbonFlux LeafCarbonPool Carbon14UptakeMethod C14 uptake is typically used for microscopic autotrophs (phytoplaknton added as bicarbonate. The plankton is removed by filtration. If the incubation is short enough, the result will be GPP (gross), because presumably, no labeled c14 was recycled (or respired) by the cells. Scales are small (hours and liters) Sometimes people do a light-dark bottle, but the dark bottle tells you something different than in o2 light-dark. It gives you dark CO2 uptake, so subtract this from light CO2 uptake if you want autotrophic GPP. BenthicAlgaeCarbonPool NetEcosystemExchangeCarbonFlux GrassCarbonPool PrimaryProductionCarbonFlux http://en.wikipedia.org/wiki/Primary_production Gross primary production (GPP) is the amount of chemical energy as biomass that primary producers create in a given length of time. (GPP is sometimes confused with Gross Primary productivity, which is the rate at which photosynthesis or chemosynthesis occurs.) For most purposes (including this one) the two can be the same. It's most practical to measure production over a given time interval and area, and that amounts to an areal rate. DissolvedOrganicCarbonFlux OxygenEvolutionLightDarkMethod The stoichiometry of phtotsynthesis is well known. So you can measure O2 evolution, and back calculate to CO2 use. usually, there is a "iight bottle" and "dark bottle". O2 evolution in the Light bottle is the net result, or sum, of all processes (GPP, Autotrophic resp, and probably some heterotrophic respiration too, because heterotrophs are hard to exclude). So Light bottle = NPP. Dark bottle is respiration, probably total, eg, autotrophs + heterotrophs. So light + dark = GPP (or about as close as you can get with a field measurement, and assume that heterotrophs aren't respiring much.) AllometricMethod an allometric method is usualy accomplished with a combintaion of measurements that are tailored to the organism, e.g, size, growth rate, carbon content, plus some loss terms. SBC's dataset 21 has a good example of an allometric method for kelp. WoodCarbonPool LeafLitterCarbonPool RespirationCarbonFlux FireCarbonFlux AutotrophicRespirationCarbonFlux