Skip to main content
SpringerLink
Log in

Organization of Fish Assemblage in the Mekong Delta as a Potential Indicator of Saltwater Intrusion

  • ICHTHYOLOGY
  • Published:
Inland Water Biology Aims and scope Submit manuscript

Abstract

The problem of saltwater intrusion into the Mekong Delta is a research topic involving various branches of science. Among the causes of this phenomenon are the global rise in sea level and the regulation of the natural river discharge due to hydropower dam construction. The scale of the delta and its water dynamics complicate instrument-based observations. Meanwhile, communities of living organisms can serve as indicators of environmental heterogeneity. This study is aimed at analyzing the spatial variability of fish assemblage organization in the Mekong Delta for use as an indicator of saltwater intrusion. The composition of fish assemblages in different parts of the delta are determined by midwater trawl catches in January and April 2021. A total of ~15 000 individual fish from 74 trawl hauls were captured and analyzed. The null hypothesis was that the fish assemblages in the Mekong Delta are represented by three taxonomic complexes that are localized in the upper course (freshwater), the lower course (brackish), and the middle course (zone of the contact of the fresh and brackish waters) of the delta. The taxonomic composition of the freshwater complex was the poorest and was represented by nine families. Meanwhile, marginal (the contact zone) and brackish complexes included 26 and 23 families, respectively. Specimens of families Cobitidae, Eleotridae, Plotosidae, and Siluridae, which are only found in the zone of contact of fresh and brackish waters, could be considered indicator species of its position. The actual boundaries of the brackish and freshwater complexes were determined and the distance from them to the marine delta edge was equal to 34 and 78 km, respectively. Assessing the salinity values that correspond to the complex boundaries is a task for future investigations. The position of the boundaries of freshwater and brackish fish taxonomic complexes has a biological basis and could be used as an indicator of salt water intrusion into the Mekong Delta.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1.
Fig. 2.
Fig. 3.
Fig. 4.

REFERENCES

  1. Binh, D.V., Kantoush, S.A., Saber, M., et al., Long-term alterations of flow regimes of the Mekong River and adaptation strategies for the Vietnamese Mekong Delta, J. Hydrol.: Reg. Stud., 2020, vol. 32, p. 100742. https://doi.org/10.1016/j.ejrh.2020.100742

    Article  Google Scholar 

  2. Boltachev, A.R., Karpova, E.P., Statkevich, S.V., et al., Characteristics of quantitative distribution of fish and decapod crustaceans in the Mekong Delta during the low-water season of 2018, Morsk. Biol. Zh., 2018, vol. 3, no. 4, p. 14. https://doi.org/10.21072/mbj.2018.03.4.02

    Article  Google Scholar 

  3. Chea, R., Lek, S., Ngor, P., and Grenouillet, G., Large-scale patterns of fish diversity and assemblage structure in the longest tropical river in Asia, Ecol. Freshwater Fish., 2017, vol. 26, no. 4, p. 575. https://doi.org/10.1111/eff.12301

    Article  Google Scholar 

  4. Cyrus, D.P. and Blaber, S.J.M., Turbidity and salinity in a tropical northern Australian estuary and their influence on fish distribution, Estuarine Coastal Shelf Sci., 1992, vol. 35, no. 6, p. 545. https://doi.org/10.1016/S0272-7714(05)80038-1

    Article  CAS  Google Scholar 

  5. Das, S.K. and Chakrabarty, D., The use of fish community structure as a measure of ecological degradation: a case study in two tropical rivers of India, BioSystems, 2007, vol. 90, no. 1, p. 188. https://doi.org/10.1016/j.biosystems.2006.08.003

    Article  CAS  PubMed  Google Scholar 

  6. Eslami, S., Hoekstra, P., Kernkamp, H.W.J., et al., Dynamics of salt intrusion in the Mekong Delta: results of field observations and integrated coastal–inland modelling, Earth Surf. Dyn., 2021, vol. 9, no. 4, p. 953. https://doi.org/10.5194/esurf-9-953-2021

    Article  Google Scholar 

  7. Huang, J., Huang, L., Wu, Z., et al., Correlation of fish assemblages with habitat and environmental variables in a headwater stream section of Lijiang River, China, Sustainability, 2019, vol. 11, no. 4, p. 1135. https://doi.org/10.3390/su11041135

    Article  Google Scholar 

  8. Karpova, E.P., Boltachev, A.R., Ablyazov, E.R., et al., Spatial variations in fish abundance in the Mekong Delta, Russ. J. Ecol., 2021, vol. 52, no. 2, p. 146. https://doi.org/10.1134/S1067413620050082

    Article  Google Scholar 

  9. Lasne, E., Bergerot, B., Lek, S., and Laffaille, P., Fish zonation and indicator species for the evaluation of the ecological status of rivers: example of the Loire basin (France), River Res. Appl., 2007, vol. 23, no. 8, p. 877. https://doi.org/10.1002/rra.1030

    Article  Google Scholar 

  10. Liu, F., Wang, J., Zhang, F.-B., et al., Spatial organisation of fish assemblages in the Chishui River, the last free-flowing tributary of the upper Yangtze River, China, Ecol. Freshwater Fish., 2020, vol. 30, no. 1, p. 48. https://doi.org/10.1111/eff.12562

    Article  Google Scholar 

  11. Miranda, R., Rios-Touma, B., Falconi-Lopez, A., et al., Evaluating the influence of environmental variables on fish assemblages along Tropical Andes: considerations from ecology to conservation, Hydrobiologia, 2022, vol. 849, no. 20, p. 4569. https://doi.org/10.1007/s10750-021-04726-3

    Article  Google Scholar 

  12. Nguyen, A.D., Savenije, H.H.G., Pham, D.N., and Tang, D.T., Using salt intrusion measurements to determine the freshwater discharge distribution over the branches of a multi-channel estuary: the Mekong Delta case, Estuarine, Coastal Shelf Sci., 2008, vol. 77, no. 3, p. 433. https://doi.org/10.1016/j.ecss.2007.10.010

    Article  CAS  Google Scholar 

  13. Nuon, V., Lek, S., Ngor, P.B., et al., Fish community responses to human-induced stresses in the Lower Mekong Basin, Water, 2020, vol. 12, no. 12, p. 3522. https://doi.org/10.3390/w12123522

    Article  Google Scholar 

  14. R: A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria. https://www.R-project.org/.

  15. Rainboth, W.J., Fishes of the Cambodian Mekong. FAO Species Identification Field Guide for Fishery Purposes, Rome: FAO, 1996.

    Google Scholar 

  16. Sharov, A.N., Tsvetkov, A.I., Korneva, L.G., and Dinh, C.N., Phytoplankton of the delta of the Mekong River during the dry season, Biosyst. Diversity, 2020, vol. 28, no. 3, p. 329. https://doi.org/10.15421/012041

    Article  Google Scholar 

  17. Steichen, J.L. and Quigg, A., Fish species as indicators of freshwater inflow within a subtropical estuary in the Gulf of Mexico, Ecol. Indic., 2018, vol. 85, p. 180. https://doi.org/10.1016/j.ecolind.2017.10.018

    Article  CAS  Google Scholar 

  18. Tan, L.V., Tran, T., and Loc, H.H., Soil and water quality indicators of diversified farming systems in a saline region of the Mekong Delta, Vietnam, Agriculture (Basel), 2020, vol. 10, no. 2, p. 38. https://doi.org/10.3390/agriculture10020038

    Article  CAS  Google Scholar 

  19. Thang, N.C., Ngoc, H.H., and Tuet, T.T., Climate change adaptation policies of Vietnam in the Mekong Delta, Vietnam. Issled., Ser. 2, 2020, no. 3. p. 36. https://doi.org/10.24411/2618-9453-2020-10023

  20. Tran, D.D., Shibukawa, K., Nguyen, P.T., et al., Fishes of the Mekong Delta, Vietnam, Can Tho: Can Tho University, 2013.

  21. Tri, D.Q., Don, N.C., Ching, C.Y., and Mishura, P.K., Modeling the influence of river flow and salinity intrusion in the Mekong River Estuary, Vietnam, Lowland Technol. Int. J., 2014, vol. 16, no. 1, p. 14. https://doi.org/10.14247/lti.16.1_14

    Article  Google Scholar 

  22. Tuan, L.A. and Chinvanno, S., Climate change in the Mekong River Delta and key concerns on future climate threats, in Environmental Change and Agricultural Sustainability in the Mekong Delta, Dordrecht: Springer-Verlag, 2011. https://doi.org/10.1007/978-94-007-0934-8_12

  23. Valbo-Jorgensen, J., Coates, D., and Hortle, K., Chapter 8— Fish diversity in the Mekong River basin, in The Mekong: Biophysical Environment of an International River Basin, Amsterdam: Elsevier, 2009. https://doi.org/10.1016/B978-0-12-374026-7.00008-5

  24. Whitfield, A.K. and Elliott, M., Fishes as indicators of environmental and ecological changes within estuaries: a review of progress and some suggestions for the future, J. Fish Biol., 2002, vol. 61, p. 229. https://doi.org/10.1111/j.1095-8649.2002.tb01773.x

    Article  Google Scholar 

  25. Wu, J., Wang, J., He, Y., and Cao, W., Fish assemblage structure in the Chishui River, a protected tributary of the Yangtze River, Knowl. Manage. Aquat. Ecosyst., 2011, vol. 400, no. 11. https://doi.org/10.1051/kmae/2011023

  26. Yuan, D., Chen, L., Luan, L., et al., Effect of salinity on the zooplankton community in the Pearl river estuary, J. Ocean Univ. China, 2020, vol. 19, no. 6, p. 1389. https://doi.org/10.1007/s11802-020-4449-6

    Article  CAS  Google Scholar 

  27. Zhang, C., Zhu, R., Sui, X., et al., Understanding patterns of taxonomic diversity, functional diversity, and ecological drivers of fish fauna in the Mekong River, Global Ecol. Conserv., 2021, vol. 28, p. e01711. https://doi.org/10.1016/j.gecco.2021.e01711

    Article  Google Scholar 

Download references

ACKNOWLEDGMENTS

We thank the staff of the Southern Branch of the Tropical Research and Technology Center (Vietnam) for their help in collecting material and organizing field trips, as well as two anonymous reviewers who made the manuscript more informative and better structured.

Funding

The material was collected with financial support from the Joint Russian-Vietnamese Tropical Research and Technology Center, research project Ekolan E-3.4 “Ecosystem of the Mekong River in the Context of Global Climate Change and Anthropogenic Impact”; the material was analyzed and the article was prepared as part of the State Task “Biodiversity, Structure and Functioning of Freshwater Fish in Continental Reservoirs and Watercourses” of the Papanin Institute for Biology of Inland Waters, Russian Academy of Sciences, topic no. 121051100104-6.

Author information

Authors and Affiliations

  1. Papanin Institute for Biology of Inland Waters, Russian Academy of Sciences, Borok, Nekouzskii raion, Yaroslavl oblast, Russia

    M. I. Malin & I. P. Malina

  2. Severtsov Institute of Ecology and Evolution, Russian Academy of Sciences, Moscow, Russia

    M. I. Malin

  3. Southern Branch of the Joint Russia-Vietnam Tropical Science and Technology Research Center, Ho Chi Minh City, Vietnam

    Truong Ba Hai, Cu Nguyen Dinh, Le Quang Man & Duong Thi Kim Chi

Authors
  1. M. I. Malin
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. I. P. Malina
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Truong Ba Hai
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Cu Nguyen Dinh
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Le Quang Man
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. Duong Thi Kim Chi
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to M. I. Malin.

Ethics declarations

Conflict of interests. The authors declare that they have no conflicts of interest.

Statement on the welfare of animals. This article does not contain any studies involving animals or human participants performed by any of the authors.

Additional information

Translated by A. Bulaev

Abbreviations: MD, Mekong Delta; MC, marginal complex; FC, freshwater complex; BC, brackish water complex; CPUE, relative abundance of taxon (catch per unit effort, ind./h).

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Malin, M.I., Malina, I.P., Hai, T.B. et al. Organization of Fish Assemblage in the Mekong Delta as a Potential Indicator of Saltwater Intrusion. Inland Water Biol 16, 319–329 (2023). https://doi.org/10.1134/S1995082923020153

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1134/S1995082923020153

Keywords:

Search

Navigation