+ Resolve Article
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter

+ Translate
+ Subscribe to Site Feed
GeoScience Most Shared ContentMost Shared Content

Uncoupling primary production from population growth in photosynthesizing organisms in aquatic ecosystems

, : Uncoupling primary production from population growth in photosynthesizing organisms in aquatic ecosystems. Aquatic Sciences 63(1): 4-17

Whenever actively photosynthesizing cells are exposed to conditions where carbon fluxes exceed intakes of other essential-nutrients required for formation of new biomass, cell division is arrested, and the excess carbon is stored, excreted or directed to secondary functions. The extent of this uncoupling and its' implications in aquatic systems are discussed. We focus on three examples: the cellular level of free living phytoplankton, the ecosystem level in the microbial food web, and the highly specialized level of species interactions in the symbiotic association between zooxanthellae and corals. These examples highlight the adaptive significance of uncoupling between photosynthesis and growth in aquatic systems. Moreover, we underscore the fact that in many real-world situations, net primary productivity cannot be equated to population growth. Roles of the "excess" carbon include photoprotective pigments and buoyancy regulating ballast. The excreted carbon compounds may protect cells or cell masses from desiccation, and fuel the microbial loop. The microbial loop increases overall nutrient extraction efficiency compared to that of which phytoplankton alone are capable. The zooxanthellae-coelenterate symbiosis drives the nutrient and energy fluxes supporting coral reef life in the nutrient-poor tropical seas. In those mutualistic associations, since photosynthesis is normally uncoupled from cell growth, the algae excrete most of their photosynthate and that supports the metabolic activities of the host.


DOI: 10.1007/pl00001343

Other references

Adams Elmo W., 1985: Memorial to Charles Mumaw Cross, 1909-1981. Memorials - Geological Society of America 15(1985

Stearn, E.W.; Sturdivant, B.F.; Stearn, A.E., 1925: The Life History of a Micro-Parasite Isolated from Carcinomatous Growths. Proceedings of the National Academy of Sciences of the United States of America 11(10): 662-669

Faraghi, N.; Ebrahimi, S., 2013: Nitrite as a candidate substrate in microbial fuel cells. Current generation using nitrite as substrate (pH 6.9, 4 mgN l<sup>?1</sup>) in a nitrite-fed microbial fuel cell was investigated under anaerobic and aerobic anodic conditions as an alternative to the biological nitrite oxidation proc...

Liu, C.; Andjelić, S.; Zhou, J.; Xu, Y.; Vailhe, C.; Vetrecin, R., 2008: Thermal stability and melt rheology of poly(p-dioxanone). Melt viscosities of poly(p-dioxanone) (PPDO) samples having different molecular weights were studied using a controlled-strain rotational rheometer under a nitrogen atmosphere. First, PPDO's thermal stability was evaluated by recording change...

Tung, C.H.; Sattler, J.I., 2001: Images in clinical medicine. Leprosy. New England Journal of Medicine 344(17): 1293-1293

Malhotra S.K.; Sawada I.; Capoor V.N., 1983: Himalaya pauriensis new genus new species as a representative of the new family himalayidae with a revised definition of the order anoplocephalidea. HIMALAYA pauriensis gen. et sp. nov., from Oryctolagus cuniculus, was described as the type species of the new family HIMALAYIDAE based on presence of a rostellum and a rostellar sac, an unusual character for the order Anoplocephalidea Wardle, McL...

Walsh, C.R.; Johnson-Laird, P.N., 2009: Changing your mind. When individuals detect an inconsistency in a set of propositions, they tend to change their minds about at least one proposition to resolve the inconsistency. The orthodox view from William James (1907) onward has been that a rational change shou...

Schram Frederick R.; Hof Cees H.J., 1993: Fossils and the interrelationships of major crustacean groups. Pages 233-302 1993

Bellapart, J.; Jones, L.; Bandeshe, H.; Boots, R., 2015: Plasma endothelin-1 as screening marker for cerebral vasospasm after subarachnoid hemorrhage. Cerebral vasospasm complicating subarachnoid hemorrhage causes ischemic stroke and worsens the neurological outcome. The potential role of endothelin-1 in vasospasm pathogenesis may provide therapeutic opportunities. A recent meta-analysis however...

Hyman L.R.; Colvin R.B.; Steinberg A.D., 1976: Immuno pathogenesis of auto immune tubulo interstitial nephritis part 1 demonstration of differential susceptibility in strain 2 and strain 13 guinea pigs. Journal of Immunology 116(2): 327-335