Monitoring Urban River Water Quality Using Macroinvertebrate and Physico-Chemical Parameters: Case study of Penchala River, Malaysia
Ahmad Abas Kutty
Mohamed Nor Mohamed Desa
A study have been carried on urban river, Sungai Penchala to assess the river water quality by using benthic macroinvertebrates as biological indicator and also standard Department of Environment (DOE) water quality measurement for physical-chemical analysis of Water Quality Index (WQI). Sampling for benthic macroinvertebrate and water sample was done on 3 sampling sites, named upstream (S1), middle stream (S2) and downstream (S3). The benthic macroinvertebrate sampling was done in the same day at the same place the water samples were collected in 5 replicates, while the water samples were collected in 3 replicates for each river section. The benthic macroinvertebrates was sampled using Surbers net and water measurement for dissolved oxygen, temperature, pH and conductivity was measured in-situ using HYDROLAB Quanta®, multi-parameter water quality instrument. Collected water sample was transferred to laboratory for measurement of total suspended solid, BOD5, chemical oxygen demand and ammoniacal nitrogen. The result from the assessment show that Sungai Penchala is classified as having good water quality on the upstream section but the water quality distorted in the middle and downstream section based on WQI and BMWP score. Non-parametric test of Kruskal-Wallis test show that most water parameter are significantly differ among river section (p>0.05, α = 0.05).
to cite this article:
Akmal Mahazar, Mohammad Shuhaimi-Othman, Ahmad Abas Kutty and Mohamed Nor Mohamed Desa, 2013. Monitoring Urban River Water Quality Using Macroinvertebrate and Physico-Chemical Parameters: Case study of Penchala River, Malaysia. Journal of Biological Sciences, 13: 474-482.
Received: March 14, 2013;
Accepted: March 30, 2013;
Published: July 12, 2013
River is very important asset that rich with benefit toward humankind especially
early civilization (Lerner and Holt, 2012). However,
the condition of river in urban area is highly influenced by the surrounding
developments. They are filled with organic and organic loads of human activities
which latter shall be carried away toward the sea and inviting another problem
(Chin, 2006; Torrisi et al.,
2010). Urban River is likely to cause problems such as flood due to the
blocked water flow and in certain country it can be a mechanism for plague and
disease transported. The river located in the urban area which heavily populated
and urbanised, even though the catchment area situated in the upstream is clean
the middle and downstream section is polluted and modified for drainage system.
Benthic macroinverterbate have long been used as biological indicator toward
environmental changes. Several studies have highlight the importance of using
benthic macroinvertebrates in monitoring purposes to support the result from
physical and chemical parameters. The reasons to use benthic macroinvertebrate
as supportive data as chemical monitoring alone is not enough as the approach
of compound by compound analysis for all chemical that might be present in the
sample is not realistic. The approach didnt account for additive, synergistic
or antagonistic effect that might occur and also lack important data such trace
metabolite and reaction products (Oertal and Salanki, 2003).
Moreover, physical-chemical data only gives information regarding the situation
of water at the time of sampling conducted (Rosenberg and
Resh, 1993). It is undeniable that benthic macroinvertebrate could serve
as good biological indicator of water quality deterioration (Turkmen
and Kazanci, 2010) as they are ubiquitous in nature, abundance and rich
with family thus offer spectrum of responses toward environmental changes; sedentary
lifestyle and long lifespan (Turkmen and Kazanci, 2010)
which making them as better candidate for biological monitoring agent when compared
to other organisms such as fish. The ubiquitous and sessile nature of benthic
macroinvertebrate could represent the condition of place the inhibit over period
of times; while varied sensitivity of each family toward various types of pollutants,
might useful to study and identify the synergistic effect of different type
of pollutants on living organism.
Thus the integration of both approaches in water quality management would gives
better understanding in the environmental condition of urban river and also
helps the management (Butiuc-Keul et al., 2012).
Therefore, the aim of this study is to determine diversity of benthic macroinvertebrates
as part of river water quality assessment especially for urban type river in
Malaysia. Supported by successful examples of the implementations and integration
of physical-chemical based approach with biological approach; this study would
open the possibilities for better understanding in water quality management
MATERIALS and METHODS
Sampling site: The samples and data collection was conducted along the
Penchala River which is one of the tributaries for highly polluted Klang River
in the Selangor state (Mak, 2004; Fazleena,
2010). This river flows through the 3 chosen sampling stations, named; upstream
(S1), middle stream (S2) and downstream (S3), respectively (Fig.
1, Table 1). The climate of the sampling area is a typical
of the Peninsular Malaysia which having moderate average annual rainfall, high
temperature and humidity.
The upstream section located deep in the recreational area which away from
residential and industrial area. The site also abundance with vegetation covers
that cover most part of the section thus limiting the direct sunlight. The middle
stream and downstream section located in the urban area which is very close
to residential area and main road. The river itself have been modified from
natural to concrete type drainage for flood mitigation and this is very much
different compared to the upstream section. Middle and downstream section have
less vegetation cover and many drainage from residential and commercial area
flow into the river. The condition of the river can change almost instantly
and this depends on other factor such as chemical loading on that moment. Foul
odour also detected on those sections.
Benthic macroinvertebrate sample collection: The benthic macroinvertebrates
sampling was done using Surbers net samplers with area size of 0.3 m2
mess size. The macroinvertebrate sampling was not randomly conducted as
the area of sampling was chosen depending on the substrates types. This is because
there is substrate preference among macroinvertebrate. Therefore, area with
substrates such as vegetation and cobbler were chosen. Between slow moving water,
ripple area with fast flowing, shallow water are the most suitable sampling
area as they support varied groups of benthic invertebrates. The Surbers
sampler was employed by placing the sampler opening facing the upstream flow.
The area in front of the sampler was disturbed for about 3 minutes. Any organism
in that area was collected by the sampler net. The sample trapped in the net
was then transferred into plastic container and preserved using 90% ethanol.
First, the sample was cleaned under slow moving water to remove any fine particles
using sieve. Then the cleaned sample was transferred into the white coloured
background container. The sorting of organism from the substrate and debris
was done under sufficient light by using forceps. Organism sorted was placed
in 75% newly added ethanol. The taxonomic identification to the family level
was done by using microscope RaxVision and also by referring to the taxonomic
reference book of Fresh Water Macroinvertebrate of the United States (Pennak,
1978) and Oligochaeta of World (Brinkhurst and Jamieson,
1971). The benthic macroinvertebrate sampled was then used in Biological
Monitoring Working Parties index (BMWP) with reference to Thailand BMWP index
(Mustow, 2002). This index was employed to determine
the water quality of Penchala River in biological aspect and chosen rather than
using other BMWP such from British or United State. Moreover Thailand have similar
climate with Malaysia.
Measurement of physical and chemical water quality variables: Prior
to sampling, all glassware and bottles used for the sampling was acid wash as
purposed by APHA (2006) to eliminate any contamination
that may influence the sample. The in-situ physical and chemical parameters
were collected using HYDROLAB Quanta®,multi-parameter water quality
|| Geographical description of sampling area
|| Sampling points along Sungai Penchala
The specification of transmitter used is on range of 2 to 12 units for pH;
0 to 50 mg L-1 for Dissolved Oxygen (DO); 0 to 1000 NTU for turbidity
and 0 to 100 m Sec cm-1 for specific conductance. Water sample for
chemical parameter variable were collected facing the upstream water (HACH,
2005). The BOD water samples were collected by filling BOD bottles in the
water without air space in the bottle and also capped while still in water.
Water samples for chemical analysis of Chemical Oxygen Demand (COD), ammoniacal
nitrogen (NH3-N) and Total Suspended Solid (TSS), were collected
in the 1 litre Teflon bottles. While water samples for BOD5 were
collected in the 300 mL BOD bottles. In total, 3 BOD bottles and 3 bottles were
used to collect water samples for each sampling sites. The water samples were
kept cool on ice of 4°C for transportation purpose from the sampling site
to the laboratory (APHA, 2006). No acid was used to preserve
the water samples as the test was conducted as soon as possible upon the time
of arrival on laboratory.
The water selected chemical analyses were done within 24 h from the time of
sampling except for BOD5 which need to be preliminarily incubated.
Prior to the analysis upon arrival at laboratories all samples were let to
room temperature. The 5 day BOD was done by primarily diluting the water samples
in station 2 and 3. Dechlorinated tap water was used for dilution purposes with
ratio water sample and dechlorinated water of 1:10, the declorinated water and
saturated with air by stirring (HACH, 2005). The first
dissolve oxygen (DO1) measurement was done after dilution using YSI
Model 5000; samples were then left for incubation for 5 days in incubator with
temperature of 20OC before be measured against for second measurement
of dissolved oxygen (DO2). The COD was done according to reactor
digestion method (Hach Method 8000). The COD digestion vial used in this study
is 0.7 to 40.0 mg L-1 COD Ultra Low Range (ULR) for COD measurement
of upstream samples and range 3 to 150 mg L-1 COD low range for measurement
of middle and downstream sections. The digestion for COD was done base on the
method stated and the measurement was taken using Hach spectrophotometer model
DR2500; programme 431 COD ULR and 430 COD LR respectively, at wavelength of
420 nm. The Total Suspended Solid (TSS) measurement was done by filtering 200
mL of water sample Whatman 934-AH Glass Microfiber filters with pore size of
0.47 μm. The microfiber filter was dried till constant weight at 105°C,
prior to filtering process and dried again after filtering the water sample
at the same temperature until it reached constant weight. The NH3-N
measurement was done according to HACH Nessler Method (Hach Method 8038) and
the measurement was done using Hach spectrophotometer model DR2500 with detection
range between 0.02 to 2.50 mg L-1 at the wavelength of 425 nm; the
water samples were diluted to 50% with deionised water before undergone analysis,
except for water sample from upstream section (S1). The data obtained from 3
replicates measurement were averaged and were used for determination of water
quality index (WQI-Table 3) based on index used by The Department
of Environment Malaysia (Department of Environment, Malaysia,
2002) as described by Norhayati et al. (1997).
This index is based on DOE opinion pool WQI and computed from equation of:
where, SI refers to the sub index function for each of the given parameters
and the coefficients are the weighting factors derived from the opinion poll
(Norhayati et al., 1997).
Statistical and data analysis : The data obtained for water quality
variable were calculated for mean and standard deviation and presented according
to the sampling site. Since the data didnt fulfil the precondition of
One-way ANOVA and cannot be transformed to suit the condition, non-parametric
test analysis of Kruska-Wallis was employed to see either there are statistically
significant differences (p<0.05) between sites. While the BMWP is calculated
using BMWPThai score system derived by Mustow
RESULTS AND DISCUSSION
Water quality variables: Table 2 show that there is
a difference among the three sites based on the temperature, conductivity, DO,
BOD, COD and NH3N. However, for pH the p-value (0.059) is greater
than 0.05 which suggest no significant difference on the three sites (Kruskal-Wallis
test). The recorded water parameter for June is similar to April but August
is different with no significant different on ammoniacal nitrogen between the
three site (Kruskal-Wallis p>0.05). This condition might due to the sampling
effort that was conducted in raining period as this might due to the dilution
of river water caused by rainfall. The increase of ammoniacal nitrogen in the
middle (S2) and downstream (S3) section indicates the discharge of untreated
wastewater into the river ecosystem. Activities such as agriculture, uncontrolled
development and surface runoff due to rainfall may contribute to the deposition
of ammoniacal nitrogen.
The Biological Oxygen Demand (BOD5), the values show variable in
high organic loading from surrounded area of S2 and S3. The foul odour experienced
while sampling on S2 and S3 with addition to low DO measurement suggested high
microbial activity due to anaerobic decomposition process of organic matter
which produce by product such as methane. S3 having the highest BOD measurement,
the BOD concentration that higher than 12 mg L-1 is part of characteristic
of Class IV river (DOE, 1985). High organic load in the
area is due to the residential area near the river and some part of the river
is treated as dumping site by resident.
The temperature of the water increase as it goes down from the upstream to
downstream and this is due to the lack of canopy cover or vegetation on the
river bank. The condition of upstream site that covered by trees and shrub cause
lower temperature on the upstream and high temperature on the middle and downstream,
this show how plant vegetation play important role in regulating temperature
in aquatic environment (Arimoro and Ikomi, 2009). The
high temperature on middle (S2) and downstream section (S3) compared to the
upstream section (S1) might also due to the altitudinal gradient, the difference
on temperature between sites may have determine the species distribution of
benthic macroinvertebrate by altering water oxygen retention capability by causing
less DO level on high temperature (Wetzel, 1983), or influencing
the thermoregulation process of benthic macroinvertebrate (Henriques-Oliveira
and Nessimian, 2010).
pH would be the most stable parameter with small differences and also most
stable for every 3 month with no drastic changes. Usually, polluted river would
have unstable pH rather than stay in stable form; in this case it is suspected
that the stable river pH is due to the geology factor as the river is situated
in area with high carbonate deposit in the form of limestone. Thus keeping the
water pH checked. However, there are also possibilities that the concrete drainage
system in the middle and downstream or from the residential area might influence
the water chemistry that flow on them.
||Range and SD for in situ parameters for 3 sampling
stations for 3 periods of months (April-August 2012)
|St: Sampljng station, P: Kruska-Wallis Test
This is due to the leaching of minerals from this infrastructure into the water
thus modified the water chemistry by making it tends to be neutral pH (Wright
et al., 2011).
The COD is higher in the middle stream (S2) and downstream section (S3) with
big difference among month of sampling. The increase of COD in those section
compared to the upstream is due to high dissolved and particulate matter in
the river. Literally high organic and inorganic compound in water body could
cause higher COD values. As for middle and downstream section huge amount of
oxygen were used to oxidise oxidisable mater in water. The source of the matter
might come from anthropogenic activities such as industrial and domestic waste
and naturally from death and as by product of living organism.
Conductivity is higher in middle (S2) and downstream section (S3) compared
to upstream (S1). Raining period might alter conductivity significantly as rainwater
have lower conductivity due to lack of minerals, this explain the huge variance
between sampling periods that was conducted in raining season. Other than that,
warmer environment of middle and downstream section increase the conductivity
of water. In upstream minerals might play important role is conductivity measurement
but for middle and downstream section conductivity might be influenced mostly
by the industrial effluent that rich with dissolved solid which carry electrical
charges. Thus we can observe high conductivity on the middle (S2) and downstream
Water quality index (WQI): The score of WQI for upstream was 96 for
April, 92 for June and 94 for August by classing the upstream river as Class
I river according to DOE (Table 3). The middle stream (S2)
was classified as Class III for the month of April and June with WQI 62 and
52, respectively. However, the WQI is the lowest on August with score of 47
classing the river as Class IV because there was construction taking place near
the river bank. While the downstream (S3) WQI would be lowest compared with
the middle stream (S2) with WQI score of 38 in April, which fall in Class IV.
The lowest WQI was on June with score of 25, (Class V) and in August the WQI
was 30 (Class IV).
The WQI reflect the condition of water quality of the river on that specific
time during the sampling period. WQI might be stable for the upstream section
(S1) as there are no sources of pollution directed into the river section. However
the middle (S2) and downstream section (S3) is as natural as the upstream section
as there are many drainage and the area have highly density due to development
and residential. Thus, the water quality is strongly influenced by human activity.
Benthic Macroinvertebrates and relation with water quality: The taxonomic
identification of family level for benthic macroinverterbates reveals that the
diversity of benthic macroinvertebrates decreases towards the river basin (S1
to S3) (Table 4). Thus the higher section of the river (S1)
with better quality has more numbers of EPT families compared with other section
of the river (S2 and S3) and this is indicated by present consistently at the
clean water on the upstream environment. The same finding also found by Chin
(2006), which found the order EPT only present in ecosystem with clean water.
The EPT order is very sensitive toward pollution because it is morphologically
susceptible to contamination especially metal contamination.
Order Chironomidae were found in high abundance on every part of river section
throughout the sampling period. Chironomidae is not considered as sensitive
order toward pollution as most of the member is quite tolerate to environmental
changes. The presence of Chironomidae is usually reported as indicator of polluted
environment by having preference on organic rich sediment (Spellman
and Drinan, 2001; Ozkan et al., 2010) as
in this case it not true for the upstream section as there are also sensitive
EPT members which suggest abundance of Chironomid is not due to pollution but
due to the capability of this order to inhibit wide range of ecosystem (Tanida,
|| DOE water index classification
|| Systematic list of taxa and number of macroinvertebrates
found along the Penchala River
Other factor that might influence the presence of Chironomidae in the upstream
is might due to the opportunistic response of the order toward abundance of
food carried by flow of water during rainfall which in this case in raining
season or from the riparian species near the river bank as upstream have more
vegetation cover on its river bank compared to middle and downstream section
(Mcshaffrey and Olive, 1985; Silva
et al., 2008).
According to the BMWP index the upper section (S1) was classed as in either
a very good water quality or good water quality with a slightly impacted which
due to the area utilized as recreation area for urban resident (Table
5). The BMWP index also supports the water quality data (WQI) which also
list the upper section in the Class I.
|| BMWP score and classes
The middle stream (S2) and downstream section (S3) of the river is either
in Class III or IV according to WQI. While the BMWP index listed the middle
in either poor or very poor category or downstream section as very poor for
the 3 month periods. This two section (S2 and S3) can be interpreted as polluted
and very polluted water, thus need an attention. The difference in WQI is because
it depends on water quality on that period of sampling, while benthic macroinvertebrate
survive and lives before the sampling was conducted could resemble the condition
of the river before the time of sampling and this provide result that measure
the effect of pollution over a period of time. The upstream section receive
less anthropogenic impact from its surrounding area which enable the good condition
for sensitive species to live as for the chemical and physical parameter indicates
this section didnt receive any organic or inorganic loads compared to
the middle and downstream section. In other perspective, the sole view toward
each the water parameters (Table 3) such as total dissolved
solid and pH and didnt give enough information about the river condition.
Thus need to be integrated in WQI calculation with support of BMWP index. The
wide differences in water quality of upstream compared to the middle and downstream
section is due to the fact that upstream section is a preserved area for public
recreation, while the middle and downstream section exposed to the rapid development
without proper planning and urban activities. It also observed the residential
and industrial sewage released to the river along the middle and downstream
section which believe to make the condition worsen. However, the increase and
decrease of benthic macroinvertebrate composition along this period of month
would indicate the positive and negative environmental condition of this urban
The variability of benthic macroinvertebrates distribution between the stations
is also influenced by the substrates of the river bed, as in this case the concrete
shaping the river, limit the presence of aquatic plant and it also observed
that the substrates in the concrete river section is more silt and sand, that
not favoured by most benthic macroinvertebrates. Thus this condition, limit
the variability of substrate on the river bed and might also limit the abundance
and types of macroinvertebrate benthic that have specific preference upon the
surrounding environment as well the substrate they live on (Mandaville,
2000). The result obtained support that the unnatural concrete river would
actually cause macroinvertebrate to decrease from the upstream section toward
the downstream. The effect of habitat modification also limits the ranges of
suitable niche for diverse benthic macroinvertebrates to fill in the ecosystem
and might reduce the function of that ecosystem. Since part of the river is
considered as clean river, where the other part is badly polluted, benthic macroinvertebrate
would be also influenced by the changes of water quality variables (Spellman
and Drinan, 2001) as it influence and limit the capabilities of benthic
macroinvertebrate that live along the river section.
There is difference water quality among the river section which indicates the
gradient of water quality from good to pollute. This is also supported with
benthic macroinvertebrate composition along the river section with the environment
sensitive families on upper section and less sensitive families on downstream
section. Therefore, through the study, we found that the water quality of Penchala
River experience degradation as it flow toward the downstream and benthic macroinvertebrates
can serves as a good biological indicator to monitor river health.
This research is a Long-term Research Grant Scheme (203/PKT/6720004) supported
by Ministry of Higher Education Malaysia. Under the title: Urban Water Cycle
Processes, Management and Societal Interactions: Crossing from Crisis to Sustainability.
With the collaboration of several educational institution as well as government
sector. The scholarship has been sponsored by Ministry of High Education under
the program of MyBrain15.
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