Browsing Cullen, John by Title
Now showing items 23-37 of 37
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Photosynthetic characteristics and estimated growth rates indicate grazing is the proximate control of primary production in the Equatorial Pacific
Macronutrients persist in the surface layer of the equatorial Pacific Ocean because the production of phytoplankton is limited. Measurements of photosynthesis as a function of irradiance (P-I) provide information on the ... -
Phytoplankton Growth and Light-Absorption as Regulated by Light, Temperature, and Nutrients
Numerous studies of the growth of phytoplankton in the laboratory have demonstrated the dependence of cellular pigment concentration and growth rate upon light intensity, photoperiod, temperature, and nutrient supply. These ... -
Predicting and verifying the intended and unintended consequences of large-scale ocean iron fertilization
Ocean iron fertilization (OIF) is being considered as a strategy for mitigating rising atmospheric CO2 concentrations. One model for implementation is the sale of carbon offsets. Modeling studies predict that OIF has the ... -
Primary production by suspended and benthic microalgae in a turbid estuary: Time-scales of variability in San Antonio Bay, Texas
The within-day, between-day and month-to-month variability of light attenuation and microalgal chlorophyll a (chl a) and photosynthetic response was measured in San Antonio Bay, Texas, USA. Waters were shallow (<2 m) ... -
Primary Production Estimates from Recordings of Solar Stimulated Fluorescence in the Equatorial Pacific at 150-Degrees-W
Biological, optical, and hydrographical data were collected on the WEC88 cruise along 150-degrees-W and during a 6-day time series station on the equator during February/March 1988. This area was characterized by a subsurface ... -
Relationships between vertical mixing and photoadaptation of phytoplankton: Similarity criteria
In their natural environment phytoplankton are exposed to fluctuations in incident irradiance due to vertical displacements in the water column induced by turbulent fluid motion. A reaction-diffusion model is analyzed to ... -
Retrieval of phytoplankton biomass from simultaneous inversion of reflectance, the diffuse attenuation coefficient, and Sun-induced fluorescence in coastal waters
[1] A model has been developed to retrieve phytoplankton absorption, a proxy for phytoplankton biomass, from observations of reflectance ( R) and the diffuse attenuation coefficient (K-d) collected by moored radiometers ... -
A semi-analytical model of the influence of phytoplankton community structure on the relationship between light attenuation and ocean color
A model was developed to examine the influence of phytoplankton community structure on the relationship between diffuse attenuation and ratios of upwelling radiance. Shifts in phytoplankton communities were represented by ... -
The spectral effects of clouds on solar irradiance
Knowledge of the spectral attenuation associated with clouds is important for accurate estimates of natural irradiance at the Earth's surface. We compare spectral measurements of visible downwelling irradiance, under varying ... -
Spectrally weighted transparency in models of water-column photosynthesis and photoinhibition by ultraviolet radiation
We present a simple method for describing the influence of variable attenuation of spectral irradiance, Kd(lambda), on water-column photosynthesis and its inhibition by ultraviolet radiation (UV). The approach is based on ... -
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Vertical migration, nutrition and toxicity in the dinoflagellate Alexandrium tamarense
The effect of nitrate-N availability on paralytic shellfish toxin production by the dinoflagellate Alexandrium tamarense was studied in a vertically stratified laboratory water column (tank) where swimming behavior could ...