Heterotrophic activity

XBw = heterotrophic active biomass in the water phase (gCOD m-3) Kx = saturation constant for hydrolysis (-)... 

Iriberri, J., Unanue, M., Barcina, I. and Egea, L. (1987). Seasonal variation in population density and heterotrophic activity of attached and free-living bacteria in coastal waters, Appl. Environ. Microbiol., 53, 2308-2314. 

Heterotrophic activity A mode of nutrition based on the oxidation of organic matter. 

Heterotrophic activity. With the DO held above 1% saturation the degree of carbonaceous degradation is largely determined by the mean treatment time and reaction temperature as described above. With lower aeration rates the DO falls to some value between 0 and 1% of saturation. 

Although phototrophs are restricted to the surface ocean, photosynthesis is the ultimate source of almost all the organic matter that supports heterotrophic activity in the sea. As shown in Figure 8.1, this organic matter is transferred through the marine food web by the feeding activities of heterotrophs including bacteria, protozoans, and animals. 

Meyer-Reil, L.-A., 1984a. Bacterial biomass and heterotrophic activity in sediments and overlying waters. In J.E. Hobbie and P.J. LeB. Williams (eds), Heterotrophic activity in the sea. Plenum Press, New York, London, pp. 523-546. 

Brooks, P. D., D. M. McKnight, and K. E. Bencala. 1999. The relationship between soil heterotrophic activity, soil dissolved organic carbon (DOC) leachate, and catchment-scale DOC export in headwater catchments. Water Resources Research 35 1895—1902. 

Bunch, J.N. (1987) Effects of petroleum releases on bacterial numbers and micro-heterotrophic activity in the water and sediment of an Arctic marine ecosystem. Arctic 40, 172-183. 

Dawson, R., and Gocke, K. (1978) Heterotrophic activity in comparison to the free amino acid concentration in Baltic Sea water samples. Oceanol. Acta 1, 45-54. 

Bihen, G. (1984). Heterotrophic utilization and regeneration of nitrogen. In Heterotrophic activity in the sea (Hobbie, and Williams, eds.). Plenum, New York. 

Second, the epiphytic microflora may start heterotrophic activity on moist plant material even before it falls to the ground. Soil animals may also initiate their activities at this stage. Soil arthropods and annelids fragment plant litter, thereby increasing the surface area amenable to microbial activity, modify organic substrates, and concentrate mineral nutrients by fecal production. 

Excess autotrophic or heterotrophic activity, and hence water pollution, is caused by acceleration of energy flow and of exchange of rates resulting from direct input of organic and inorganic waste constituents into receiving waters. 

The universal association of enzymes with life and the occurrence of organisms in all areas of the marine environment has evoked interest in the study of this class of compound. Besides the determination of heterotrophic activity and knowledge of the presence of particular strains of bacteria, the measurement of enzymatic activity may give further insight into degradation processes of in situ produced organic matter. 

Cavari, B.Z. and Hadas, O., 1979. Heterotrophic activity, glucose uptake and primary productivity in Lake Kinneret. Freshwater Biol., 9 329—338. 

---