Long-Term Variation of Surface Water Quality at Bung Binh Thien, An Giang Province, Vietnam

Abstract

This study uses the principal component analysis (PCA) to assess the
variation of surface water quality in the Bung Binh Thien area (BBT),
An Giang province. The samples of surface water quality were
collected at three locations in BBT (BT1-BT3), with the frequencies of
three times per year in March, June and September in the period from
2009 to 2020. The parameters of temperature, pH, total suspended
solids (TSS), dissolved oxygen (DO), biochemical oxygen demand
(BOD), chemical oxygen demand (COD), nitrate (N-NO3
-
), ammonium
(N-NH4
+
), orthophosphate (P-PO4
3-
) and coliform were analysed for
surface water quality assessment. The results showed that pH and
temperature were within the allowable limits. The water quality at BBT
was contaminated by organic matters, nutrients and coliform in which
TSS and coliform were the most severe. The water quality in 2012 and
2017 was worse than the water quality in other years. PCA showed that
the temperature, pH, TSS, DO, BOD, N-NO3
-
, P-PO4
3-
, and coliform
had significant influence on the surface water quality due to the
potential pollution sources from domestic waste, livestock, aquaculture
and agriculture.