Key variables affecting surface water quality in Kien Giang province, Vietnam

IJEP 42(8): 899-908 : Vol. 42 Issue. 8 (August 2022)

Nguyen Thanh-Giao1* and Tran Vang-Phu2

1. Can Tho University, College of Environment and Natural Resources, Vietnam
2. Can Tho University, School of Law, Vietnam

Abstract

The study was conducted to assess surface water quality and identify the main parameters influencing the surface water in Kien Giang province; study took the monitoring data at 49 locations in 2019. Water quality variables were pH, temperature, conductivity (EC), salinity, total suspended solids (TSS), dissolved oxygen (DO), biochemical oxygen demand (BOD), chemical oxygen demand (COD), orthophosphate (PO43--P), ammonium (NH4+-N), nitrate (NO3-N), nitrite (NO2-N), total iron (Fe), chloride (Cl) and coliform. Surface water quality was assessed using QCVN 08-MT:2015/BTNMT and water quality index (WQI). Principal component analysis (PCA) was used to determine main water quality parameters influencing water quality. The findings presented that water environment in Kien Giang province was polluted by organic matters (DO was low; TSS, COD and BOD were high), nutrients (PO43--P, NH4+-N, NO3-N, NO2-N), microorganisms (coliform) and Fe. WQI values indicated that water quality in the rainy season was worse than that in the dry season, mainly from poor to moderate. The PCA results showed that EC, salinity, Fe, Cl, BOD, COD, NO3-N, PO43--N and coliform significantly influenced surface water quality. Therefore, these water variables should be included in the annual monitoring programme in Kien Giang province. The main sources of surface water pollution could be agriculture drainage, dead aquaculture, domestic activities, untreated pollutant/wastewater from industry, river bank erosion and hydrological factors. However, in order to properly manage the surface water quality, the sources of pollution need to be soon identified.

Keywords

Water quality, Kien Giang, Principal component analysis, water quality index, pollution, water pollution

References

  1. QCVN 08-MT:2015/BTNMT. National technical regulation on surface water quality. Socialist Republic of Vietnam.
  2. Vega, M., et al. 1998. Assessment of seasonal and polluting effects on the quality of river water by exploratory data analysis. Water Res., 32:3581-3592.
  3. Chounlamany, V., M.A. Tanchuling and T. Inoue. 2017. Spatial and temporal variation of water quality of a segment of Marikina river using multivariate statistical methods. Water Sci. Tech., 66(6): 1510-1522.
  4. Zeinalzadeh, K. and E. Rezaei. 2017. Determining spatial and temporal changes of surface water quality using principal component analysis. J. Hydrol. Regional Studies. 13:1-10.
  5. Giao, N.T. 2020. Evaluating current water quality monitoring system on Hau river, Mekong data, Vietnam using multivariate statistical technique. J. Appl. Env. Res., 42(1):14-25.
  6. Feher, I.C., M. Zaharie and I. Oprean 2016. Spatial and seasonal variation of organic pollutants in surface water using multivariate statistical techniques. Water Sci. Tech., 74:1726-1735.
  7. TCVN 6663-6. 2018. Water quality-sampling part 6: Guidelines for sampling river and stream water. Ministry of Science and Technology, Socialist Republic of Vietnam.
  8. TCVN 6663-3. 2016. Water quality-sampling part 3: Water sample storage and treatment. Ministry of Science and Technology, Socialist Republic of Vietnam.
  9. APHA. 1998. Standard methods for the examination of water and wastewater (20th edn). American Public Health Association, Washington DC.
  10. Vietnam Environment Administration. 2019. Decision 1460/QD-TCMT dated 12/11/2019 of the Vietnam Environ-ment Administration on the promulgation of technical guidelines for calculation and publication of Vietnam’s water quality index.
  11. Liu, C.W., K.H. Lin and Y.M. Kuo. 2003. Application of factor analysis in the assessment of groundwater quality in a block foot diseases area in Taiwan. Sci. Total Env., 313:77-89.
  12. Boyd, C.E. 1998. Water quality for pond aquaculture. Research and Development Series (No. 43). International Centre for Aquaculture and Aquatic Environments, Alabama Aquaculture Experimental Station, Auburn University.
  13. Lien, N.T.K., et al. 2016. Water quality in the main and fast rivers belongs to the Hau river route. Sci. J. Can Tho University. 43:68-79.
  14. Ly, N.H.T. and N.T. Giao. 2019. Surface water quality in canals in An Giang province, Vietnam from 2009 to 2016. J. Vietnamese. 10(2):113-119.
  15. Tuan, D.D.A., N.H. Trung and B.A. Thu. 2019. Assessment the current state of surface water quality for water exploitation and supply for Soc Trang city. J. Sci. Can Tho University. 55(4):61-70.
  16. Toan, V. T., Cheng and E. Baran. 2007. Study on characteristics of some water environment indicators and composition of wild shrimp and fish species in Bac Lieu province. Sci. J. Can Tho University. 8:139-148.
  17. Ministry of Natural Resources and Environment. 2012. Report the current state of surface water.
  18. Giao, N.T. and H.T.H. Nhien. 2020. Phytoplankton-water quality relationship in water bodies in the Mekong Delta, Vietnam. J. Appl. Env. Res., 42(2):1-12.
  19. Giau, V.T.N., P.T. Tuyen and N.H. Tung. 2019. Assessment of surface water quality fluctuation of Can Tho river in the period 2010-2014 by calculation method of WQI water quality index. Sci. J. Can Tho University. 55(2):105-113.
  20. Barkat, A., et al. 2016. Assessment of spatial and seasonal water quality variation of Oum Er Rbia river (Morocco) using multivariate statistical techniques. Int. Soil Water Conser. Res., 4(4):284-292.
  21. Ut, V. N. 2013. Research on measures to limit the growth of Limmoperna fortunei mussels living on rice snails (Cipangopaludina lecithoides) in Cho Lach district, Ben Tre. Final report of Ministry level project.
  22. Bolstad, P.V. and W.T. Swank. 1997. Cumulative impacts of land-use on water quality in a southern Appalachian water shed. J. American Water Resour. Assoc., 33(3):519-533.
  23. UNICEF. 2008. Handbook on water quality. United Nation Children’s Fund, New York.
  24. Varal, M. and B. Sen. 2009. Assessment of surface water quality using multivariate statistical techniques : A case study of Behrimaz stream, Turkey. Env. Monit. Assess., 159:543-553.