Effects of high latitude UV radiation on phytoplankton and nekton modelled from field measurements by simple algorithms

[摘要] Irradiance measurements from the Barents Sea and coastal areas of northern Norway were used to calibrate a simple-algorithm empirical model that simulate PAR, UVR and UVR inhibition of phytoplankton carbon assimilation. Field measurements showed that UVR levels, in addition to solar zenith angle, were controlled by variations in cloudiness and probably also ozone layer thickness. The relative amount of UV-B and UV-A to PAR increased during periods with heavy cloud cover. Inhibition of phytoplankton photosynthesis, obtained from incubation experiments, was between 50 and 75% close to the surface and was detectable down to ca. 10m depth. The common spring bloom phytoplankter Phaeocystis pouchetii was less sensitive to UVR than centric diatoms. Critical depths (Dcr) for increase in phytoplankton biomass modelled from a 40-year time series of meteorological data from Lofoten were shallower during periods with elevated UVR levels, but we suggest that total annual production is not severely affected. Nauplii of...

[学科分类] 自然科学（综合）