Abstract
ABSTRACTThe highly stratified, oligotrophic regions of the oceans are predominantly nitrogen limited in the surface ocean and light limited at the deep chlorophyll maximum (DCM). Hence, determining light and nitrogen co-limitation patterns for diverse phytoplankton taxa is crucial to understanding marine primary production throughout the euphotic zone. During two cruises in the deep-water Gulf of Mexico, we measured primary productivity (H13CO3−), nitrate uptake (15NO3−), and ammonium uptake (15NH4+) throughout the water column. Primary productivity declined with depth from the mixed-layer to the DCM, averaging 27.1 mmol C m−2 d−1. The fraction of growth supported by NO3− was consistently low, with upper euphotic zone values ranging from 0.01 to 0.14 and lower euphotic zone values ranging from 0.03 to 0.44. Nitrate uptake showed strong diel patterns (maximum during the day), while ammonium uptake exhibited no diel variability. To parameterize taxon-specific phytoplankton nutrient and light utilization, we used a data assimilation approach (Bayesian Markov Chain Monte Carlo) including primary productivity, nutrient uptake, and taxon-specific growth rate measurements. Parameters derived from this analysis define distinct niches for five phytoplankton taxa (Prochlorococcus, Synechococcus, diatoms, dinoflagellates, and prymnesiophytes) and may be useful for constraining biogeochemical models of oligotrophic open-ocean systems.
Publisher
Cold Spring Harbor Laboratory
Reference112 articles.
1. Plankton functional type modelling: running before we can walk?
2. Evaluation of the current state of mechanistic aquatic biogeochemical modeling;Mar. Ecol. Prog. Ser,2004
3. Barton, A. D. , Lozier, M. S. and Williams, R. G. (2015) Physical controls of variability in North Atlantic phytoplankton communities. Limnol. Oceanogr., 60, 181-197.
4. Elemental composition of marine Prochlorococcus and Synechococcus: Implications for the ecological stoichiometry of the sea;Limnol. Oceanogr,2003
5. Nutrients, plankton, and productivity in a warm-core ring in the western Gulf of Mexico;J. Geophys. Res: Oceans,1992
Cited by
4 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献