Evaluating Air Quality in Hau Giang Province, Vietnam Using Multivariate Statistical Analysis

Abstract

Air pollution not only has serious impacts on public health, but also
affects ecosystems and increases the impact of climate change. This
study evaluated air quality at 13 locations (one base station (KK01)
and 12 impact stations (KK02, KK03, KK04, KK05, KK06, KK07,
KK08, KK11, KK12, KK14, KK19 and KK28)) belonging to eight
districts, towns and cities in Hau Giang province with a frequency of
six times/year (January, March, May, July, September, and
November) with four replicates in each monitoring phase. Noise, total
suspended particles (TSP), nitrogen dioxide (NO2), sulfur dioxide
(SO2), carbon monoxide (CO) and hydrogen sulfide (H2S) parameters
are used to evaluate the quality of the air environment. Noise is
compared with national technical regulations on noise (QCVN 26:
2010/BTNMT), H2S is compared with national technical regulations
on some hazardous substances in ambient air (QCVN 06:
2009/BTBMT), while the remaining indicators are evaluated using
national technical regulations on ambient air quality (QCVN 05:
2013/BTNMT). Methods of cluster analysis (CA) and principal
component analysis (PCA) are used to group air quality and main
indicators affecting the quality of the air environment. Research
results show that, the air environment in Hau Giang province in 2020
is mainly noise pollution. The criteria including TSP, NO2, SO2, CO
and H2S are within the permissible limits of current regulations. The
PCA results show that 6 indicators selected for the initial monitoring
all contribute to the impact on air quality in the area. Sources of air
pollutants generated by vehicles in main traffic axes, centers,
industrial activities, coal-making villages, gases generated from
landfills, people's activities through cooking process. Analysis of CA
according to the observed frequency shows that air quality is divided
into two groups mainly due to TSP. The CA results by locations show
that the choice of the base ambient air monitoring location is
satisfactory because the base and impact monitoring points are
classified into two distinct groups. Research results provide important
information on environmental quality and the significance of the
monitoring indicators selection.