Phytoplankton extracellular production has been determined kinetically during the spring phytoplankton bloom in three marine biotopes representative of the Southern North Sea (Scheldt estuary, Belgian coast and English Channel), differing greatly in their biological activities. Short-term kinetics of phytoplankton extracellular compounds produced during 14C incubations have been shown to increa...

I measured physico-chemical properties and phytoplankton in the small, shallow tropical reservoir of Oyun (Offa, Nigeria) between January 2002 and December 2003. I identified 25 phytoplankton genera in three sampling stations. Bacillariophyceae dominated (75.3%), followed by Chlorophyceae (12.2%), Cyanobacteria (11.1%) and Desmidiaceae (0.73%). The high amount of nutrients (e.g. nitrate, phosph...

Nutrient availability is one of the major factors regulating marine productivity and phytoplankton community structure. While the response of phytoplankton species to nutrient variation is relatively well known, that of phytoplankton community remains unclear. We question whether phytoplankton community growth rates respond to nutrient concentration in a similar manner to phytoplankton species ...

Anthropogenic alterations of nutrient inputs and food-web structure are two of the primary stressors affecting lake phytoplankton. This paper explores the independent and interactive effects of nutrients and food-web structure (as indexed by zooplankton size) on phytoplankton size structure by fitting time-series models to data from three lakes where both factors have been manipulated. I assess...

phytoplankton and zooplankton concentrations in pishin reservoir are predicted employing a three-dimensional numerical model in this paper. modeling is performed using a numerical model based on mass transport equation. advection, diffusion and source/sink processes are considered as separate subroutines for predicting the concentrations of phytoplankton and zooplankton in the reservoir. finite...

phytoplankton and zooplankton concentrations in pishin reservoir are predicted employing a three-dimensional numerical model in this paper. modeling is performed using a numerical model based on mass transport equation. advection, diffusion and source/sink processes are considered as separate subroutines for predicting the concentrations of phytoplankton and zooplankton in the reservoir. finit...

light is never being distributed homogeneously and it forms a gradient over biomass. the unidirectional nature of light gives rise to a vertical gradient of light intensity as a function of depth. the maximum depth of the light zone suitable for phytoplankton photosynthesis is designated as the euphotic depth. this study was designed to test the hypothesis of mixing depth of phytoplankton and i...

background and objectives: phytoplanktons are organisms with a very high diversities and global distribution in different habitats. the high distribution of phytoplankton is due to ecological flexibility and their ability to tolerate different climatic conditions and environmental stress. phytoplankton is the most sensitive biological indicators of water resources. the purpose of this study was...

Phytoplankton require light for photosynthesis. Yet, most phytoplankton species are heavier than water and therefore sink. How can these sinking species persist? Somehow, the answer should lie in the turbulent motion that redisperses sinking phytoplankton over the vertical water column. Here, we show, using a reaction-advection-diffusion equation of light-limited phytoplankton, that there is a ...

The relationship between biodiversity and ecosystem functioning is a central issue in ecology, but how this relationship is affected by nutrient stress is still unknown. In this study, we analyzed the phytoplankton diversity effects on community biomass and stability along nutrient gradients in an artificial eutrophic lake. Four nutrient gradients, varying from slightly eutrophic to highly eutr...