Freshwater algal blooms

Algal blooms, See Freshwater algal blooms Altera scripta, 126... 

Onodera H, Satake M, Oshima Y, Yasumoto T, Carmichael WW (1997) New saxitoxin analogues from the freshwater cyanobacterium Lyngbya wollei. Nat Toxins 5 146-151 Paerl HW, Fulton III RS, Moisander PH, Dyble J (2001) Harmful freshwater algal blooms, with an emphasis on cyanobacteria. Sci World 1 76-113 Pouria S, de Andrade A, Barbosa J, Cavalcanti R, Barreto V, Ward C, Preiser W, Poon G, Neild G, Codd G (1998) Fatal microcystin intoxication in haemodialysis unit in Caruaru, Brazil. Lancet 352 21-26... 

Pickhardt PC, Folt CL, Chen CY, Klaue B, Blum JD. 2002. Algal blooms reduce the uptake of toxic methyhnercury in freshwater food webs. Proc Nat Acad Sci 99 4419 1423. 

Therefore, preservation of acceptable water quahty and reversal of eutrophication in these systems will invariably include reductions of current loads and setting limits on new N input, either alone or in combination with other nutrient (e.g., P) input reductions. Freshwater nutrient management has, in many instances, successfully arrested and reversed eutrophication by reducing P loadings (Edmondson, 1970 Likens, 1972 VoUenweider, 1982). Indeed, the upstream freshwater portions of many estuaries are also P-Hmited (Boynton and Kemp, 2000 Fisher et al, 1999), and P input constraints in these waters have been quite successful in reducing the unwanted symptoms of eutrophication (nuisance algal blooms, toxicity, hypoxia,... 

In freshwater aquatic systems, cyanobacteria are believed to account for up to 78% of the total fixed nitrogen (Mague, 1977). These symbiotic organisms have been found to vary with season and often to precede, and be part of, algal blooms. This can lead to eutrophication of an aquatic system, by supplying NH3, one of the nutrients essential to all plant life. In... 

Freshwater phytoplankton blooms commonly occur in reservoirs, lakes, canals, and ponds under eutrophic and other physicochemical conditions that are favorable for bloom formation. Among the different types of phytoplankton blooms that can occur in freshwater ecosystems, cyanobacterial (blue-green algal) blooms are usually the most undesirable for the following reasons 1) certain species of cyanobacteria can produce toxins that kill aquatic and terrestrial animal life 2) some species of cyanobacteria produce off-flavor compounds that can impart an undesirable taste to cultured fish 3) cyanobacteria are a poor base for... 

Oshima, Y., Chemical and enzymatic transformation of paralytic shellfish toxins in marine organisms. In Harmful Marine Algal Blooms, Lassus, R, et al., eds., Lavoisier Intercept Ltd., Paris, p. 475, 1995. Shimizu, Y., Chemistry and mechanism of action. In Seafood and Freshwater Toxins, Botana, L.M., ed., Marcel Dekker, Basel, p. 151, 2000. 

Rhodes L.L., Haywood, A.J., Ballantine, W.J., and Mackenzie, A.L Algal blooms and climate anomalies in north-east New Zealand, August-December 1992, NZ. J. Mar. Freshwat. Res., 27, 419-430, 1993. 

Recknagel, F., Bobbin, J., Whigham, P., and Wilson, H., 2002. Comparative application of artificial neural networks and genetic algorithms for multivariate time-series modeling of algal blooms in freshwater lakes. Journal of Hydroinformatics 4(2), p.l25-134. 

In freshwater, harmful algal blooms are mostly attributed to cyanobacteria, also known as blue-green algae. Cyanobacterial neurotoxins fall into three different categories anatoxin-a and homoanatoxin-a, anatoxin-a(S), and saxitoxins (see Figure 1 and Figure 5 for chemical structures). As mentioned above, saxitoxins are produced by marine dinoflagel-lates and are known to concentrate in seafood and cause PSP in humans. Saxitoxins can be also found in cyanobacteria, where the presence of at least 19 different saxitoxins has been reported. 

Hudnell, H.K., 2010. The state of US freshwater harmful algal blooms assessments, policy and legislation. Toxicon 55 (5), 1024-1034. 

Ibelings, B.W., Havens, K.E., 2008. Cyanobacterial toxins a qualitative metaanalysis of concentrations, dosage and effects in freshwater, estuarine and marine biota In Hudnell, H.K. (Ed.), Cyanobacterial Harmful Algal Blooms State of the Science and Research Needs. Advances in experimental medicine and biology, vol. 619, Springer, New York, pp. 675-732. 

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