Phytoplankton and Trophic Gradients pp 217-227 | Cite as
The phytoplankton succession in the lower part of hypertrophic Nakdong River (Mulgum), South Korea
Abstract
Investigations were carried out to determine the mechanism of phytoplankton succession in the lower part of Nakdong River. Intensive monitoring was conducted from April 1993 to April 1995 at weekly or biweekly intervals. This river is the main source of drinking water for more than 8 million residents living in Pusan and the Southeastern region of Korea, and it is also important for industrial purposes. Due to the rapid urbanization and industrialization, this river has become hypertrophic and it is heavily regulated (mean chl. a, 79 ± 232 µg 1−1 n = 76; mean TN, 4.3 ± 2.0 mg 1−1 n = 30; mean TP, 165 + 108 µg 1−1 n = 45). Bacillariophyceae were dominant year-round in 1993, with spring and late fall peaks. Dominant communities in 1994 were Bacillariophyceae in March and April, Chlorophyceae and Cryptophyceae in May, Cyanobacteria in July and August, Chlorophyceae and Cryptophyceae in October, and Bacillariophyceae in December. As drought persisted through the summer of 1994, elevated water temperature (over 30 °C) possibly triggered Cyanobacteria bloom (mainly Microcystis aeruginosa, maximum cell density, 1.6 × 107 cells m1−1). The most common diatom, Stephanodiscus hantzschii, repeatedly dominated from late fall to next spring (mean and maximum cell density, 7.5 × 104, 1.2 × 105 cells m1−1, respectively). This small centric diatom was favored by the low discharge and the cold water (water temperature, 3–10 °C). After the diatom bloom, this community shifted to peaks of colonial Chlorophyceae and motile Cryptophyceae, owing to the high rate of zooplankton grazing activity and increased water temperature. Overall, the phytoplankton periodicity was primarily governed by the hydrologic regime (discharge). Changes in silica concentration, water temperature and high zooplankton density might have played an important role in phytoplankton dynamics during the non-flooding periods. Compared to other large rivers, strong Microcystis bloom events in summer and Stephanodiscus bloom events in winter were noticeable in the dry year. The patterns of phytoplankton succession observed in this study may have a significance since most of the large rivers in Far Eastern Asian countries are subjected to eutrophication and regulation of discharge.
Key words
regulated river Microcystis bloom Discharge Temperature community compositionPreview
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References
- Descy, J. R, P. Servais, J. S. Smitz, G. Billen and E. Everbecq, 1987. Phytoplankton biomass and production in the River Meuse (Belgium). Arch. Hydrobiol. Algol. Stud. 78: 225–245.Google Scholar
- Descy, J. P., 1993. Ecology of the phytoplankton of the River Moselle: effects of disturbances on community structure and diversity. Hydrobiologia 249: 111–116.CrossRefGoogle Scholar
- Gamier, J., G. Billen and M. Coste, 1995. Seasonal succession of diatoms and Chlorophyceae in the drainage network of the Seine River: Observations and modeling. Limnol. Oceanogr. 40: 750765.Google Scholar
- Gosselain, V., J. P. Descy and E. Everbecq, 1994. The phytoplankton community of the River Meuse, Belgium: seasonal dynamics (year 1992) and the possible incidence of zooplankton grazing. Hydrobiologia 289: 179–191.CrossRefGoogle Scholar
- Ha, K., 1996. The mechanism of phytoplankton succession in the lower part of Nakdong River. M.S. Thesis. Pusan National University, Pusan, 86 pp.Google Scholar
- Harris, G. P., 1986. Phytoplankton Ecology. Chapman and Hall, New York, 327 pp.CrossRefGoogle Scholar
- Jones, G. J. (ed), 1994. Cyanobacterial Research in Australia. CSIRO, Canberra, 193 pp.Google Scholar
- Joo, G. J., 1990. Limnological studies of oxbow lakes in the Southeastern United States: Morphometry, physico-chemical characteristics and patterns of primary productivity. The University of Alabama, Tuscaloosa, PhD. dissertation, 122 pp.Google Scholar
- Joo, G. J., 1995. Ecological Studies on the Nakdong River (19571994). Kumjung Press, Pusan, 178 pp (in Korean).Google Scholar
- Kim, H. W., 1996. Characteristics of physico-chemical parameters and zooplankton dynamics in the Nakdong River. M.S. Thesis. Pusan National University, Pusan, 87 pp.Google Scholar
- King, D. L., 1970. The role of carbon in eutrophication. J. Wat. Pollut. Cont. Fed. 42: 2035–2051.Google Scholar
- Kiss, K. T., 1987. Phytoplankton studies in the Szigetkoz section of the Danube during 1981–1982. Arch. Hydrobiol. Suppl. 78: 247–273.Google Scholar
- Lampert, W., Fleckner, W., Rai, H. and B. E. Taylor, 1986. Phytoplankton control by grazing zooplankton: A study on the spring clear-water phase. Limnol. Oceanogr. 31: 478–490.Google Scholar
- McQueen, D. J. and D. R. S. Lean, 1987. Influence of water ternperature and nitrogen to phosphorus ratio on the dominance of blue-green algae in Lake St. George, Ontario. Can. J. Fish. aquat. Sci. 44: 598–604.Google Scholar
- Moed, J. R., H. L. Hoogveld and W. Apeldoorn, 1976. Dominant diatoms in Tjeukemeer ( The Netherlands ): II. Silicon depletion. Freshwat. B iol. 6: 355–362.Google Scholar
- OECD., 1982. Eutrophication of waters: Monitoring, assessment and control. Paris, 154 pp.Google Scholar
- Paerl, H. W. and J. F. Ustach, 1982. Blue-green algal scums: An explanation for their occurrence during freshwater blooms. Limnol. Oceanogr. 27: 212–217.Google Scholar
- Paerl, H. W., 1987, Dynamics of Blue-green algal (Microcystis aeruginosa) blooms in the lower Neuse River, North Carolina: Causative factors and potential controls. Water Resources Research Institute of the University of North Carolina., 164 pp. UNC-WRRI-87–229.Google Scholar
- Reynolds, C. S., 1984a. The ecology of freshwater phytoplankton. Cambridge Univ. Press, Cambridge and New York, 384 pp.Google Scholar
- Reynolds, C. S., 1984b. Phytoplankton periodicity: the interactions of form, function and environmental variability. Freshwat. Biol. 14: 111–142.Google Scholar
- Reynolds, C. S., 1988. The concept of ecological succession applied to seasonal periodicity of freshwater phytoplankton. Verh. int. Ver. Limnol 23–683–691.Google Scholar
- Reynolds, C. S., J. Padisâk and U. Sommer, 1993. Intermediate disturbance in the ecology of phytoplankton and the maintenance of species diversity: A synthesis. Hydrobiologia 249: 183–188.Google Scholar
- Reynolds, C. S. and J. P. Descy, 1996. The production, biomass and structure ofj phytoplankton in large rivers. Arch. Hydrobiol. Sup-pl. 113, Large rivers 101–4: 161–187.Google Scholar
- Sell, D. W., H. J. Carney and G. L. Fahnenstiel, 1984. Inferring competition between natural phytoplankton populations: The Lake Michigan example reexamined. Ecology 65: 325–328.Google Scholar
- Shannon, C. E. and W. Weaver, 1949. The Mathematical Theory of Communication. Urbana, Univ. Illinois Press, 117 pp.Google Scholar
- Shapiro, J., B. Forsberg, V. Lamarra, M. Lynch, E. Smeltzer and G. Zoto, 1982. Experiments and experiences in biomanipulation: studies of biological ways to reduce algal abundance and eliminate blue–greens. EPA 600/3–82–096, 251 pp.Google Scholar
- Shapiro, J., 1990. Current beliefs regarding dominance by blue-greens: The case for the importance of CO2 and pH. Verh. int. Ver. Limnol. 24: 38–54.Google Scholar
- Sommer, U. (ed.), 1989. Plankton Ecology. Springer-Verlag, Berlin, 358 pp.CrossRefGoogle Scholar
- Sommer, U., 1985. Comparison between steady state and non-steady state competition: Experiments with natural phytoplankton. Limnol. Oceanogr. 30: 335–346.Google Scholar
- Song, K. 0., 1992. Water quality modeling in the Nakdong River. PhD. dissertation. National Fisheries, University of Pusan, Pusan, 134 pp.Google Scholar
- Stoyneva, M. P. and S. J. Draganov, 1991. Green algae in the phytoplankton of the Danube (Bulgarian sector) — species composition, distribution, cell numbers and biomass. Arch. Protistenkd. 139: 243–260.Google Scholar
- Wetzel, R. G., 1983. Limnology. 2nd Edition. Saunders College Publishing, Philadelphia, 860 pp.Google Scholar