Study of the Impacts of Some Domestic Pollutants on the Freshwater Fish Community in the Klang River , Malaysia

This study was carried out to determine the effects of sewage pollution on the fish assemblages found in the Klang River. Samples were collected between July 2012 and April 2013 with a total of 102 specimens belonging to 5 freshwater fish species, Puntius hexazona, Betta livida, Neohomaloptera johorensis, Parosphromenus harveyi and the dominant species, Rasbora sumatrana, with the highest dominance value (Di%=36.66). Multiregression revealed a statistically insignificant relationship among the physical, chemical and biochemical parameters of water and sediment and Puntius hexazona, Betta livida, Neohomaloptera johorensis and Parosphromenus harveyi. Based on multiple regression tests, a significant relationship with R = 92.2% and F= 7.876 (p= 0.000) was found between six water and sediment quality constituents and the numbers of Rasbora sumatrana this species at the stations studied at Site 8. On the other hand, water temperature (β= -0.114; t= -2.811 (p= 0.016)); sediment organic matter (β= -0.011; t= -2.406 (p= 0.033)) and water phosphorus (PO4) (β= 0.323; t= 3.444 (p= 0.005)) were found to be the most important water and sediment parameters effecting Rasbora sumatrana.


Introduction
Water is the basic unit of life.Fresh water is a limited resource that is as important for industry and agriculture as for human existence (Khalil and Ouarda, 2009;Bartram and Ballance, 1996).There is presently an emphasis on diffuse rather than point sources of water pollution.These adverse effects on water are a result of increasing water demand from agriculture, industry, hydroelectric generation, and continued pollution.The consequences are further exacerbated by population growth, rapid urbanization and climate change (Birol et al., 2006;UNEP, 2000).From an economic perspective, water resources are over-extracted and not efficiently allocated.This is due in part to the existence of market and government failure at the local, national and international levels.Private costs and benefits diverge from social costs and benefits, leading to social welfare losses (Birol et al., 2006;Proops, 1991).The monitoring of environmental parameters is one of the highest priorities in the evaluation of the environmental status of water resources and in environmental protection policy.
The main objectives are to understand and evaluate water availability and quality, to control and Chordates are mostly used as bioindicators and biomonitors in different aquatic ecosystems; they are known as bioindicators in polluted areas (Rinderhagen et al., 2000).Sewage pollution impacts benthic organisms.Changes due to pollution are primarily determined by the community structure of benthic fauna (Arasaki et al., 2004).Although some temporary changes in organic matter have been observed due to the initial stages of sewage pollution, sensitive species soon leave the polluted zone if pollution is a persistent problem (Bat et al., 2001).Determining the distribution of indicator species is crucial in mapping pollution gradients (Corbera and Cardell, 1995).Many studies on this topic have been carried out on polychaetes and mollusks (Belan, 1967) Chordates are the most sensitive of benthic organisms affected by sewage pollution [Bat et al., 2001;Delval et al., 1998;Guerra-García and García-Gómez, 2004).Physical environmental factors and pollutant concentrations are important in the determination of the benthic community, and low biodiversity has been observed in sewagepollution-affected areas in coastal zones (Morrisey et al., 2003).The effects of sewage pollution on chordates in the Mediterranean ecosystem have been found in the following studies.Del Valls et al. (1998) and Guerra-García and García-Gómez (2004) studied the effects of sewage pollution on crustaceans found in the soft bottoms of two different littoral systems of Cadiz Bay (the eastern Atlantic) and of Ceuta Harbor (Gibraltar Strait).
Additionally, Garcia Raso and Manjon Cabeza (2002) determined the effects of sewage pollution on decapod crustaceans in the upper-infralittoral zone of the Barbate Coast (the southern Spain).
Recently, in Abu-Qir Bay (Alexandria, Egypt) where organic pollution occurs, Hamouda and Abdel-Salam (2010) studied the distribution models of macrobenthic communities, including cumaceans.Their findings indicated that extreme organic pollution can cause the elimination of sensitive species in an environment (Hamouda and Abdel-Salam, 2010).
On the Turkish coasts, Bat et al.The aim of this study is to determine the effects of sewage pollution on the chordate assemblages on the soft bottoms of the Klang River, an important river in the Selangor basin.

Study Area
The Klang River (including its major

Sample collection, study area and field measurements
The study area is located along the Klang  the high-temperature oxidation method adopted by Craft et al. (1991).In addition to loss of ignition at 550 °C using a furnace, organic carbon and total nitrogen were also determined by the hightemperature oxidation method.The loss of ignition method requires a weighed dry material and a furnace programmed for slowly increasing temperature to 550 °C, followed by holding for 1 to 2 hours at this temperature.TOC analyzers are gaining in favor because of the short test periods required.Clean sand samples were also tested to compare with the results obtained from sediment samples.

Water Quality Parameters
Dissolved oxygen, water temperature, electrical conductivity, pH and salinity were measured using a YSI 556 model MPS on site.
Water samples were collected in 1-liter clean, darkcolored glass bottles.Ammonia, nitrate, nitrite, biological oxygen demand, chemical oxygen demand, and anionic detergents were determined using Standard Methods (APHA, 2005).Moreover, organic constituents in the water were determined using a Hach-5000 spectrophotometer.Three replicates were tested for all parameters, and statistically no differences were found after data evaluation.Quality control was ensured when testing parameters in the laboratory.

Ecological Data Analyses
A triocular stereomicroscope was used to identify fish specimens found in the study area.

Statistical Data Analyses
Variance analyses were completed to see whether there were significant differences among sampling sites and between sampling times (seasons).These analyses were completed using SPSS 10.0.Moreover, physical and chemical water quality parameters were tested to determine which ones were correlated.The Friedmann test was adopted to calculate the fish species distribution with respect to seasonal changes.
Where b is the number of sampling stations (8) and t is the number of seasons (4) S j : standard deviation of the data set All collected parameters were evaluated using MANOVA (multiple analysis of variance).
The relationship between species composition and pollutants was evaluated using Spearman's Correlation.The relationship between the physicochemical parameters and domestic pollutants in river water was determined by canonical discriminant analysis.

Environmental conditions
The seasonal mean dissolved oxygen (DO) concentration was 7.13 (±0.59) mg/L.However, the highest ammonia concentration of all sampling stations was found in site 3discharge at        Discharge sites 3 and 4 were both observed to be the cleanest in terms of anionic detergent concentration, with 0.19 mg/L.The highest average anionic detergent concentration among all sampling stations was computed to be 0.63 and 0.62 mg/L at discharge sites 3 and 4 (Table 3).

Faunal Composition
A total of 102 specimens belong to 5 fish species in the soft river bottoms at depths between 0 and 5 m of 8 different stations (6 discharges, 2 references) in the Klang River was reported.The highest number of specimens was found at the site 3 discharge station (42 specimens), and the lowest value was 4 at discharge sites 6 and 7 (Fig. 2, Table 5).In the study area, the maximum number of species ( 5 was reported in April 2012 (Fig. 3).Sewage pollution can change the structural integrity of biodiversity (Terlizzi et al., 2002).Several benthic groups such as macroalgae, tunicates, poriferans, bivalves, and crustaceans are impacted where domestic pollution is a reality.Moreover, the present populations of these organisms are declining with respect to time (Chapman et al., 1995) because domestic wastes bring nitrogen, organic carbon, and phosphorus into aquatic systems.In other words, sewage pollution is a mixture of many types of toxic matter, and it harmfully affects the biota.Eutrophication plays an important role in the destruction of biodiversity in aquatic environments (Elmanama et al., 2006).
In the presence of pollution, the dominant fish species between 5 and 13 m are reported to be Puntius hexazona and Betta livida, Neohomaloptera johorensis and Parosphromenus harveyi and Rasbora sumatrana below 20 m by Corbera and Cardell (1995).In addition, sediment organic matter was found to be between 0.6 and 1.1% in Barcelona, Spain (Corbera and Cardell, 1995).Corbera and Cardell (1995) also reported that Rasbora sumatrana has the highest biomass value and its presence is triggered with the increase of pollution.In our study, the observed chordates were Neohomaloptera johorensis, Parosphromenus harveyi and Rasbora sumatrana.These species were found in the monsoon season when the sediment organic matter was 1.95±0.69%.
Moreover, these species were found to be dominant at depths between 0 and 2 m.The most dominant species were found to be Puntius hexazona (Di=35.29%)and Betta livida (Di=32.35%).
Physical environmental factors and the concentrations of pollutants in seawater are important in determining the benthic community structure, and in polluted areas, the community has low species diversity (Morrisey et al., 2003).This status was the same for site 4, 5 and 6 discharges.However, fewer species were recorded than expected, due to the effect of sediment, strong currents and wind on aquatic pollutants.

Conclusion
The findings from this study indicate that the Klang (2001)    described the effects of domestic wastewater discharge on several crustacean species at the depths of 0.5-1 m on the coast of Sinop Harbor (the southern Black Sea).Albayrak et al. (2006) sampled four different locations in the northern Marmara Sea to determine the levels of pollution due to organic material discharges.Tuğrul İçemer and Koşun (2003) carried out a study characterizing the benthic community structure subjected to sewage pollution in Antalya Bay (the eastern Mediterranean).Similar to our study, Corbera and Cardell (1995) studied indicative cumaceans affected by eutrophication in the soft bottoms of the Barcelona coast (southern Spain).Despite several studies that have examined the effects of pollution on benthic communities of the Turkish coast (Tuğrul İçemer and Koşun (2003) for the Mediterranean Sea; Kocataş et al. (1988) for the Aegean Sea; Albayrak et al. (2006) for the Sea of Marmara; Okuş et al. (1996), Yüksek et al. (2006) for the Bosporus; Bat et al. (2001) for the Black Sea), no research has indicated the effect of sewage pollutants on the structure of macrozoobenthic communities in relation to environmental conditions in the Dardanelles.The Dardanelles is a long, narrow, and shallow strait.Saros Bay, located in the northern part of the Dardanelles, is known as an important area for fisheries activity, and water from the Black Sea is discharged into the northern Aegean and the Saros after passing through the Dardanelles.Therefore, all water flowing from the Black Sea drains through this region.Thus, any type of pollution is highly expected to accumulate in the region.
tributaries of Batu, Gombak, Kerayong, and Pencala) may not be the largest in Malaysia, but the Klang Valley, which it drains, is the most developed and anthropogenically altered portion of the country.Beginning some 100 km from the Straits of Malacca in the Main Range of Peninsular Malaysia, it flows through the national capital of Kuala Lumpur, Petaling Jaya, Shah Alam, and Klang before reaching the sea at Port Klang.The Klang River is approximately 120 km long, covering a total catchment area of 1288 km.With almost a seventh of the national population and the widest range of human activities, the physical environment in the Klang Valley has undergone many man-made changes, ranging from tin-mining during the 19th century to extensive urbanization and industrialization today.The Klang River has had to bear the full brunt of all these changes.

Figure 1 :
Figure 1: Klang River catchment The Klang River faced huge threats from various sources over ten years ago due to various types of industrial activities such as the production of food and beverages, chemical manufacturing, semiconductor and electrical industries, etc.Indeed, rivers flowing through heavily populated areas are

Figure 2 :
Figure 2: Klang River tributariesKlang's Environmental StressesAs recently as the turn of the century, the Klang River was navigable up to the point where it meets the Gombak.However, tin-mining, which contributed to the birth of Kuala Lumpur, was also one of the first major environmental stresses of the river as it discharged loads of silt into the Klang.The clearing of the jungle, first for rubber, then for buildings and roads, and finally for oil palm, increased erosion in the Klang Valley.The result has been the silting of the entire river system so that effective navigation is possible only up to the outskirts of Shah Alam.Despite the fact that tinmining is on the decline, additional silt now comes from badly managed infrastructure.As human population density increased in the valley and sanitation facilities failed to keep up with this growth, organic pollution of the river became serious.Although more sewage now ends in treatment plants, increased kitchen and other organic waste still moves through poorly maintained drains and ends up in the Klang River.It appears that many residents and even some officials tend to treat the river as a sewer and

Figure 1 .
Figure 1.The study area includes 8 sampling points; 4 are located on the Anatolian coast and the other 4 are located on the European side.The GPS coordinates of the sampling stations are as follows:Samples of fish species at depths of 0 to 5 m were collected from three different transects frequency index (¦f%),Bellan- Santini's (1969) quantitative dominance index (Di%), and Shannon's diversity index (1949) (Hˊ), as well as its evenness component (Jˊ) andBray- Curtis's (1957) similarity index were calculated.The community structure was investigated by group-averaging cluster analysis based on Bray-Curtis similarity.To calculate Shannon's diversity index (Hˊ) and its evenness component (Jˊ), primer program 6.0 was used.The frequency index of a particular species was estimated by f= (m/M)x100 Where m is the number of stations where the species of concern exists M is the total number of stations The dominance index of a certain species was estimated by Di = (m/M) x 100, where m = number of individuals of a species at a station and M = total number of individuals of all species.The Shannon-Weaver diversity index was estimated by H´= -Σ p i x (log 2 p i ), Where S = total number of individuals of a species and N =total number of individuals of all species.The Pielou evenness index was estimated by J´= H´/ log 2 S where H'= Shannon index value; S = species number Bray-Curtis Sjk=100 {1-|Σ|y ij -y ik |/Σ|yij + yik||}

Figure 3 :
Figure 3: Number of species and individuals recorded at the sampling stations.
number of species and individuals The number of specimens significant differences in salinity and electrical conductivity, according to two-way analysis of variance (MANOVA).on all sampling times and locations, was computed as 35.94 (±50.26)mg/L.The highest ammonia levels were found in site 5 and site 8 discharges as 168 and 166 mg/L, respectively, in July 2012.Sites 6 and 7 both had the lowest ammonia concentration of 0.06 mg/L in April 2013.Moreover, site 4 underwent the greatest change in NH 4 + content, improving from 3.68 mg/L in July 2012 to 0.05 mg/L in February 2013.The lowest mean ammonia concentration (1.35 mg/L) was found at site 5, taking into account all individual samplings without considering times.

Figure 4 :
Figure 4: Number of species and individuals found during the sampling seasons.
The mean sediment organic matter (percent SOM) of all sampling times and locations was computed as 2.85 (±2.16) %.The maximum SOM level was found at site discharge 2 as 9.86% in April 2013, possibly due to less variation in temperature, continuous sewage discharge and the structure of the site because it is less affected by flow in the strait.The lowest SOM (0.55%) 3 because the highest flow in the strait is near this site.As expected, site 3 was recorded with the lowest SOM as 1.75%.The maximum mean SOM without taking into account individual sampling times (5.01%) was detected at discharge site 8.The mean anionic detergent value across all sampling times and locations was computed as 0.04 (±0.02) mg/L.

Figure 6 :
Figure 6: Diversity (Hˊ) and evenness (Jˊ) in the seasons found here appeared to constitute permanent components of the fauna (with f% values >50).In July 2013, the highest number of individuals was observed (n=48), while Betta livida and Rasbora sumatrana were observed to have a maximum number of individuals (N=17) in this period.

Figure 7 :
Figure 7: Similarity of the chordates community in the sampling seasons (Bray-Curtis index).
) was recorded in the 2012 and 2013 monsoon seasons.The fewest species were observed in July 2012 with 3 species.The highest number of individuals (58 specimens) was recorded in November 2013.This season was followed by July 2012 with 34 specimens and February 2012 with 15 specimens.The lowest value (5 specimens)

Figure 8 :
Figure 8: Similarity of the chordates community at the sampling stations (Bray-Curtis index).The diversity index values (Hˊ) at the sampling stations ranged between 0.46 and 1.91.
While no species was recorded for site 7 discharge in the summer sampling, the same station had 21 chordate specimens in the spring season.The number of species for discharge point sites 2 and 3 were both 0 in the summer and were 3 and 5, respectively, in the spring This seasonal increase in the number of specimens can be explained by excess precipitation during the spring: the additional freshwater input to the stream led to the dilution of local contaminants at site 6.The deep discharge of domestic sewage at site 8, caused no direct stream impacts to the horizontal surface layer, and the associated pollutants can be transported away from the discharge point.Denitrification occurs via nitrite and nitrate in water, and nitrous oxides are converted(Sawyer et al., 2003).Site 4 discharges more NH 4 + and NO 3 -throughout the year than other stations, and its high content of accumulated sediments affects the presence of organic debris in the long term.Nitrate, one of the most important forms of nitrogen or phosphorus to biological life forms, is a characteristic of site 8 throughout the year.The organic matter content of the water in the river most likely varies with the convection dynamics.The north-east wind is generally strong, and the strong southward currents in the region have led to the removal of pollutants from the study area.Based on our observations, discharges are especially intense at night in the monsoon period in parts of the residential area of the strait.The impact of these discharges under the influence of wind and river currents may dissipate in the morning, but during the discharge period, the sunlight is less intense.Canonical Discriminant Analysis showed that anionic detergent concentration and phosphorus concentration are the main factors among all physical and chemical factors examined in the study.Wilks' Lambda was found to be 4.981 (p=0.018) for anionic detergent and 4.977 (p=0.002) for phosphorus.Discriminant function analysis showed that physical and chemical constituents measured in this study differ notably in monsoon compared to other seasons.It is hard to tell, however, whether temperature, fresh water inputs to the system or both together cause differences among the parameters examined.It could be concluded that some physical and chemical constituents differ due to summer resorts, seasonal runoff differences, and most importantly temperature in the study area.With the expected population change, increases in some physical and chemical water quality parameters will most likely be experienced in the future if pollution control measures are not taken beforehand.
River water quality has been improving since 1998 in the middle and upstream stretches and has been improving since 2002-2003 in the downstream stretches.The tributaries started to show a positive trend in 2001-2003.Water quality enhancement is highly dependent on improved wastewater and sewage treatments, other improvement efforts and policies under government initiatives, and people's awareness of the need to preserve our vital water resources.Numerous campaigns and awareness programs have been promoted by the government since the 1990s to recover river water quality.The 'Love Our River Campaign' was launched in 1992 to improve the waterfront and river.This is considered to be the most comprehensive long-term awareness program on water resources in Malaysia.The campaign aimed to promote public awareness of the importance of rivers and highlight the critical state of river pollution.In addition, six main programs were carried out during this program, namely River Adoption, River Watch, River Expeditions, Education (talks, visits, briefings, etc.), River Beautification and Love Our Rivers Month.The 7 th Malaysia Plan (1996-2000) not only focused upon ensuring more sustainable development through environment preservation but also emphasized the integration of environmental considerations with the economic and social development process.Education on environmental awareness and campaigns was also intensified to ensure active participation from all sections of society.

Table 1
found to create significant differences in DO, pH and sea water temperature.However, both sampling times and sampling sites were found to create

Table 2 .
Ammonia, nitrate, nitrite, and phosphate concentrations found during the study

Table 3 .
Sediment organic matter and anionic detergent content measured during the study

Table 5 .
Number of specimens recorded at the sampling stations during the study.