Heterotrophic plankton

Bode, A., Barquero, S., Gonzalez, N., Alvarez-Ossorio, M. T., and Varela, M. (2004a). Contribution of heterotrophic plankton to nitrogen regeneration in the upweDing ecosystem of A Coruna (NW Spain). /. Plankton Res. 26(1), 11—28. 

Vadstein, O. (1994) The role of heterotrophic, planktonic bacteria in the cycling of phosphorus in lakes phosphorus requirements, competitive ability and food web interactions. PhD thesis, University of Trondheim (cited by Gismervik etal., 1996). 

Vadstein, O. (1998) Evaluation of competitive ability of two heterotrophic planktonic bacteria under phosphorus limitation. Aquatic Microbial Ecology 14, 119-127. 

Vadstein, O. (2000) Heterotrophic, planktonic bacteria and cycling of phosphorus phosphorus requirements, competitive ability, and food web interactions. Advances in Microbial Ecology 16, 115M67. 

Heterotrophic microbes consume organic matter to fuel respiration metabolisms that provide energy. Aerobic respiration of the Redfield-Richards planktonic organic matter can be represented stoichiometrically as... 

At mid-latitudes (Westerlies domain), seasonal changes in light availability, mixed layer depth, and temperature support two plankton blooms, one in the spring and a lesser one in the fall (Figure 24.10). In the winter, phytoplankton growth is light limited. (The carbon fixation reaction is also slower at lower temperatures.) Thus as heterotrophic microbes remineralize detrital POM, DIN concentrations rise. 

Biological. In an enclosed marine ecosystem containing planktonic primary production and heterotrophic benthos, the major metabolites were water soluble and could not be extracted with... 

Fig.1 Generalized pelagic food web [ 13]. The old view of a simple food chain vertical line in this figure) with phytoplankton (mainly diatoms) at the base, herbivorous mesozoo-plankton (mainly copepods) at the second trophic level, and planktivorous fish has been extended to a pelagic food web including nanoplankton (<20 pm), picoplankton (<2 pm), and their protozoan feeders lower left). Herbivorous tunicates and jellyfish as primary carnivores also play a role, as do mixotrophic flagellates. The main pathway of energy flow depends on the nutrient scenarios [13]. DOC=dissolved organic carbon, HNF=heterotrophic nanoflageUates. From [13] with permission of Kluwer Academic Press...

Recycling of N and P occurs in the water column and at interfaces between the water and substrata such as profundal sediments. In Lake Calado, regeneration of ammonium and phosphorus is dominated by planktonic heterotrophs less than 53 pm in size (Table 14.7, Lenz et al. 1986, Fisher et al. 1988a, Fisher et al. 1988b, Morrissey and Fisher 1988). Sediment-water exchange is smaller than planktonic processes, but is substantial... 

Nitrification is the process whereby ammonium (NH4+) is oxidized to nitrite (N02 ) and then to nitrate (N03 ). It thus links the most oxidized and most reduced components of the nitrogen (N) redox cycle and helps determine the overall distributions of these important nutrients. Ammonium rarely occurs at significant concentrations in oxygenated habitats. It is recycled rapidly between heterotrophic and N2 fixing organisms (which excrete NH4+ directly or release organic N that is microbiaUy degraded to NH4+) and many heterotrophic and photosynthetic plankton (which utilize NH4+ as a N source) in the surface ocean. 

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