We consider plankton-nutrient interaction models consisting of phytoplankton, herbivorous zooplankton and dissolved limiting nutrient with general nutrient uptake functions and instantaneous nutrient recycling. For the model with constant nutrient input and different constant washout rates, conditions for boundedness of the solutions, existence and stability of non-negative equilibria, as well ...

A 153 kHz narrowband acoustic Doppler current profiler (ADCP) was used to measure volume backscattering strength (Sv) during a deepwater oceanographic survey of cetacean and seabird habitat in the northeastern Gulf of Mexico. Sv was positively related to zooplankton and micronekton biomass (wet displacement volume) in ‘sea-truth’ net hauls made with a 1m Multiple Opening-Closing Net Environment...

Traditionally, large planktivorous elasmobranchs have been thought to predominantly feed on surface zooplankton during daytime hours. However, the recent application of molecular methods to examine long-term assimilated diets, has revealed that these species likely gain the majority from deeper or demersal sources. Signature fatty acid analysis (FA) of muscle tissue was used to examine the assi...

The reduced zooplankton abundance at the outlet sections of lakes depends on the occurrence of preying fry. Therefore, light conditions can play a major role in the drift of zooplankton along river outlets. The aim of this study was to determine the influence of diurnal light conditions on the decline of zooplankton densities at lake outlets. Photosynthetically active radiation (PAR) levels wer...

Relegated to the benthos, the blue mussel, Mytilus edulis, is confined to consuming resources available in the water above substrates. However, aquaculture manipulates the distribution of mussels and renders the resources of the water column available to mussels. With the identification of mussels as significant consumers of zooplankton, the presence of mussels in the water column suggests aqua...

We compared the stable carbon isotopic composition (d13C) of crustacean zooplankton with that of potential carbon sources in 15 lakes in northern Sweden with different dissolved organic carbon (DOC) concentrations (2–9 mg L21) to test the hypothesis that zooplankton depended more on allochthonous carbon in humic lakes than in clear-water lakes. Based on d13C signature, we found that the pool of...

The primary goal during FY01/02 was to quantitatively assess zooplankton distributions and species in Knight Inlet, with special focus on the sill near Hoeya Head. This area has been the subject of considerable ONR-sponsored oceanographic research in the past focused on the stratified flow features induced by the sill (e.g. Farmer and Armi 1999; Klymak and Gregg 2001). Echo-sounder surveys perf...

The present work aims to study the Zooplankton seasonal distribution and diversity in Karanja reservoir, Bidar district for the period of two years from October 2001 to September 2003. We have recorded 36 species of which, 15 species belongs to rotifera, 11 species belongs to cladocera, nine species belongs to copepoda and ostracoda three species. Among zooplankton, particularly rotifera was th...

plankton studies are one of the major items of the marine scientific activities in the ropme seaarea, whereas numerous investigations have been conducted on the plankton during the past century. forphytoplankton, species composition, abundance and biomass, primary production, harmful algal blooms, redtide, toxic species, and eutrophication were considered. zooplankton studies included species c...

The ability of raptorial zooplankton to find large particles such as marine aggregates is crucial to their use of the particles as food and to the fate of the particles. Kiørboe & Thygesen (2001) developed a numerical approach to describe particle detection by chemosensory zooplankton. In this paper, we develop and test a simplified mathematical description of the process and explore the ecolog...