Variation of phytoplankton community structure in Quang Ngai coastal waters during 2015–2019


  • Huynh Thi Ngoc Duyen Institute of Oceanography, VAST, Vietnam
  • Tran Thi Minh Hue Institute of Oceanography, VAST, Vietnam
  • Tran Thi Le Van Institute of Oceanography, VAST, Vietnam
  • Phan Tan Luom Institute of Oceanography, VAST, Vietnam Graduate University of Science and Technology, VAST, Vietnam
  • Nguyen Ngoc Lam Institute of Oceanography, VAST, Vietnam
  • Doan Nhu Hai Institute of Oceanography, VAST, Vietnam



Ly Son, Quang Ngai, phytoplankton, diversity index.


Phytoplankton in coastal waters are important for the evaluation of either biodiversity or environmental impacts because of this highly vulnerable ecosystem. Seasonal and annual changes in the phytoplankton community structure in Quang Ngai waters during the period 2015 to 2019 were analyzed to assess the phytoplankton diversity and reveal possible causes of these changes. A total of 366 phytoplankton taxa belonging to 10 classes were identified throughout this present study. The highest species number was found in 2019 with 295 taxa, followed by those in 2015 (247), 2017 (185), and 2018 (99). The waters of Ly Son transect showed the highest diversity and most stable phytoplankton communities in both dry and rainy seasons, whereas the stations of Quang Ngai coast revealed high variability of the communities. All diversity indices including Margalef, Pielou, Shannon, Simpson did not reflect well differences in average values but a certain degree of variances, indicating possible environmental impacts. During the study time, there were blooms of certain diatom species including Skeletonema spp. in 2015 and Pseudo-nitzschia spp. in 2019. Analysis of a diatoms index, Centric/Pennate ratio, indicated that the waters were in eutrophic status with a decreasing trend from the coast area to Ly Son island in 2015 and 2019. This research built up fundamental data on phytoplankton communities for Quang Ngai province. The Centric/Pennate diatom index and diversity would be used as indicators for environmental changes and their values provided warning of eutrophication in this coastal waters including the water surrounding Ly Son island.


Download data is not yet available.


[1] Field, C. B., Behrenfeld, M. J., Randerson, J. T., and Falkowski, P., 1998. Primary production of the biosphere: integrating terrestrial and oceanic components. Science, 281(5374), 237–240. Doi: 10.1126/science.281.5374.237

[2] EPA, 2005. New Indicators of Coastal Ecosystem Condition, Office of Research and Development Washington DC, EPA/600/S-05/004.

[3] Falkowski, P. G., Fenchel, T., and Delong, E. F., 2008. The microbial engines that drive Earth's biogeochemical cycles. Science, 320(5879), 1034–1039. Doi: 10.1126/science.1153213.

[4] Litchman, E., and Klausmeier, C. A., 2008. Trait-based community ecology of phytoplankton. Annual Review of Ecology, Evolution, and Systematics, 39, 615–639.

[5] Li, W. K., McLaughlin, F. A., Lovejoy, C., and Carmack, E. C., 2009. Smallest algae thrive as the Arctic Ocean freshens. Science, 326(5952), 539–539. DOI: 10.1126/science.1179798.

[6] Sathicq, M. B., Bauer, D. E., and Gómez, N., 2015. Influence of El Niño Southern Oscillation phenomenon on coastal phytoplankton in a mixohaline ecosystem on the southeastern of South America: Río de la Plata estuary. Marine Pollution Bulletin, 98(1–2), 26–33.

[7] Huisman, J. M., Matthijs, H. C. P., and Visser, P. M., 2005. Harmful Cyanobacteria. In: Springer Aquatic Ecology Series 3. Springer, Dordrecht, the Netherlands. 243 p.

[8] Fritz, L., and Triemer, R. E., 1985. A rapid simple technique utilizing calcofluor white M2R for the visualization of dinoflagellate thecal plates. Journal of Phycology, 21(4), 662–664.

[9] Graham, H. W., and Bronikovsky, N., 1944. The genus Ceratium in the Pacific and northern Atlantic Oceans. Scientific Results Cruise VII. In Biological Series (Vol. 5, p. 209). Carnegie Institute of Washington Publication 565.

[10] Hoang Quoc Truong, 1962. Phytoplankton in Nha Trang bay - 1: Bacillariales. - Univerarea de Sai Gon. - Annales de la Faculté des Saigon. Contribution No. 59, 121–214. (in Vietnamese).

[11] Hoang Quoc Truong, 1963. Phytoplankton in Nha Trang Bay - 2. Dinoflagellages. - Institut Océanographique de Nha Trang. - Annales de la Faculté des Saigon 2, 129–176. (in Vietnamese).

[12] Shirota, A., 1966. The plankton of South Vietnam: fresh water and marine plankton. Overseas Technical Cooperation Agency.

[13] Abé, T. H., 1981. Studies on the family Peridinea an unfinished monograph of the armoured Dinoflagellates. Publications of the Seto Marine Biological Laboratory.

[14] Balech, E., 1988. Una especie nueva del género Fragilidium (Dinoflagellata) de la bahía de Chamela, Jalisco, México. Anales del Instituto Biologica UNAM, Series Zoologica, 58, 479–486.

[15] Truong Ngoc An, 1993. Classification of marine phytoplankton in Vietnam. Science and Technics Publishing, Hanoi, 315 p.

[16] Licea-Durán, S., Moreno-Ruiz, J. L., Santoyo-Reyes, H., and Figueroa, G., 1995. Dinoflageladas del Golfo de California. Universidad Autónoma de Baja California Sur, Secretaría de Educación Pública, Fondo para la Modernización de la Educación Superior, Programa Interdisciplinario e Insterinstitucional del Mar de Cortés. México, DF.

[17] Moreno, J. L., Licea, S., and Santoyo, H., 1996. Diatomeas del Golfo de California Sur (pp. 272). México: Universidad Autónoma de Baja California Sur.

[18] Tomas, C. R. (Ed.), 1997. Identifying marine phytoplankton. Elsevier.

[19] Larsen, J., and Lam, N. N., 2004. Potentially toxic microalgae of Vietnamese waters. Opera Botanica, (140), 5–216.

[20] Nguyen-Ngoc, L., and Larsen, J., 2008. On the genus Alexandrium (Dinoflagellata) in Vietnamese waters: - two new records of A. satoanum and A. tamutum. In: Proceedings, International Conference on Harmful Algae. International Society for the Study of Harmful Algae and Intergovernmental Oceanographic Commission of UNESCO, Copenhagen. Moestrup Ø., et al., pp. 216–218.

[21] Nguyen-Ngoc, L., Ho-Van, T., and Larsen, J., 2012. A taxonomic Account of Ceratium (Dinoflagellates) in Vietnamese Waters. The Thailand Natural History Museum Journal, 6(1), 25–59.

[22] Doan-Nhu, H., Nguyen-Ngoc, L., Anh, N. T. M., Larsen, J., and Thoi, N. C., 2014. Diatom genus Chaetoceros Ehrenberg 1844 in Vietnamese waters. Nova Hedwigia, (143), 159–222. 14/009.

[23] Phan-Tan, L., Nguyen-Ngoc, L., and Doan-Nhu, H., 2016. Species diversity of sections conica and tabulata in the genus Protoperidinium (Dinophyceae) from tropical waters of the South China Sea. Nova Hedwigia, 103(3–4), 515–545.

[24] Phan‐Tan, L., Nguyen‐Ngoc, L., Doan‐Nhu, H., Raine, R., and Larsen, J., 2017. Species diversity of Protoperidinium sect. Oceanica (Dinophyceae, Peridiniales) in Vietnamese waters, with description of the new species P. larsenii sp. nov. Nordic Journal of Botany, 35(2), 129–146.

[25] Guiry, M. D., and Guiry, G. M., 2020. AlgaeBase. World-wide electronic publication, National University of Ireland, Galway.; searched on 16 May 2020.

[26] Soumia, A., 1978. Phytoplankton manual. United Nations Educational, Scientific and Cultural Organization.

[27] Margalef, D. R., 1957. Information theory in ecology.(reprinted in 1958). Gen. Syst, 3, 37–71.

[28] Pielou, E. C., 1966. The measurement of diversity in different types of biological collections. Journal of theoretical biology, 13, 131–144. 0022-5193(66)90013-0.

[29] Shannon, C. E., 1948. A mathematical theory of communication. The Bell System Technical Journal, 27(3), 379–423. Doi: 10.1002/j.1538-7305.1948.tb01338.x.

[30] Simpson, E. H., 1949. Measurement of diversity. Nature, 163(4148), 688–688.

[31] Bray, J. R., and Curtis, J. T., 1957. An ordination of the upland forest communities of southern Wisconsin. Ecological Monographs, 27(4), 326–349.

[32] Clarke, K. R., 1993. Non‐parametric multivariate analyses of changes in community structure. Australian Journal of Ecology, 18(1), 117–143.

[33] Wickham, H., François, R., Henry, L., and Müller, K., 2018. dplyr: A grammar of data manipulation, R package version 0.7. 6 [Computer software manual].

[34] Giraudoux, P., 2017. Data Analysis in Ecology, Package ‘pgirmess’. Version 1.6.7.

[35] Wickham, H., 2009. Elegant graphics for data analysis (ggplot2).

[36] Oksanen, J., 2019. Vegan: ecological diversity. Version 2.5-5.

[37] Tran Thi Le Van, Doan Nhu Hai, Phan Tan Luom, Nguyen Thi Mai Anh, Tran Thi Minh Hue, Huynh Thi Ngoc Duyen, 2018. Phytoplankton in coastal waters of Da Nang province. Vietnam Journal of Marine Science and Technology, 18(4A), 43–58.

[38] Huynh Thi Ngoc Duyen, Phan Tan Luom, Tran Thi Le Van, Tran Thi Minh Hue, Nguyen Ngoc Lam, Doan Nhu Hai, 2019. Diversity of phytoplankton in lower Thu Bon river and Cu Lao Cham. Vietnam Journal of Marine Science and Technology, 19(4A), 215–227.

[39] Doan-Nhu, H., Nguyen-Ngoc, L., and Nguyen, C. T., 2016. ENSO and anthropogenic impacts on phytoplankton diversity in tropical coastal waters. Progress in Oceanography, 140, 1–13.

[40] Rousseaux, C. S., and Gregg, W. W., 2012. Climate variability and phytoplankton composition in the Pacific Ocean. Journal of Geophysical Research: Oceans, 117(C10). Doi: 10.1029/2012JC008083.

[41] Kemp, W. M., Boynton, W. R., Adolf, J. E., Boesch, D. F., Boicourt, W. C., Brush, G., Cornwell, J. C., Fisher, T. R., Glibert, P. M., Hagy, J. D., Harding, L. W., Houde, E. D., Kimmel, D. G., Miller, W. D., Newell, R. I. E., Roman, M. R., Smith, E. M., and Stevenson, J. C. 2005. Eutrophication of Chesapeake Bay: historical trends and ecological interactions. Marine Ecology Progress Series, 303(21), 1–29. Doi: 10.3354/meps303001.

[42] Huynh Thi Ngoc Duyen, Nguyen Thi Mai Anh, Nguyen Chi Thoi, Tran Thi Le Van, Phan Tan Luom, Nguyen Ngoc Lam and Doan Nhu Hai, 2015. Assessment on trophic status of Nha Trang bay using environmental and phytoplankton based indices. Academia Journal of Biology, 37(4), 446–457.