Thursday 23 June 2011

A Study on Dissolved Oxygen, pH and Temperature of the Lake Water in Pengkalan Gawi-Pulau Dula Section of Tasik Kenyir, Terengganu

Kamaruddin, I.S., A.S. Mustafa Kamal, A. Christianus, and S.K. Daud, (2010). A study on dissolved oxygen, pH and temperature of the lake water in Pengkalan Gawi – Pulau Dula Section of Kenyir Lake, Terengganu. Towards a Healthier and Sustainable Future: International Annual Symposium on Sustainability Science and Management (UMTAS 2010). Universiti Malaysia Terengganu. 9(2): 482-486.


A Study on Dissolved Oxygen, pH and Temperature of the Lake Water in Pengkalan Gawi-Pulau Dula Section of Tasik Kenyir, Terengganu

1st Kamaruddin, I.S., *2nd A.S. Mustafa Kamal, 3rd A. Christianus and 4th S.K. Daud
1st, 2nd, 3rd Department of Aquaculture, Faculty of Agriculture, Universiti Putra Malaysia, 43400, UPM Serdang, Selangor, Malaysia.
4thDepartment of Biology, Faculty of Science, Universiti Putra Malaysia, 43400, UPM Serdang, Selangor, Malaysia.
*Corresponding author: E-mail: akuakultur_upm@hotmail.com

Abstract
A study was conducted to evaluate the dissolved oxygen, D.O. (mg/l), hydrogen ion concentration, (pH) and temperature (°C) of the lake water in Pengkalan Gawi – Pulau Dula section of Tasik Kenyir, Terengganu. Water samples were collected monthly from March 2008 to January 2009 (11 months) at three sampling stations designated as station A (Pulau Dula), station B (Sungai Ikan) and station C (Pulau Pupi). Water samples were collected using 1-litre polyethylene bottles that were washed with acid hydrochloric. The results of the study showed that the mean values of the studied water quality parameters for the entire study period were as follows: D.O. = 6.18 mg/l ± 0.49; pH = 6.91 ± 0.46; water temperature = 29.8 °C ± 1.33. Across months, all water quality parameters remained more or less constant with little or no monthly variations. Across sampling stations, the results showed that, except for pH, there were no statistically significant differences among stations in the values of other water quality parameters. pH readings were significantly different between Sungai Ikan and Pulau Pupi. The overall results of this study showed that the water quality parameters of the Pengkalan Gawi – Pulau Dula section of Tasik Kenyir remained within acceptable ranges. Management and conservation programs for Tasik Kenyir that are sustainable should be stressed in order to maintain and stabilize the water quality of the lake. 
Keywords: Dissolved Oxygen, pH, Temperature, Lake, Tasik Kenyir


INTRODUCTION
Being a reservoir, the water level of a lake varies every month. Hydroelectric impoundments used mainly for power production often are more like giant riverine pools than lakes because of the high turnover rate of the water (Moyle and Cech, 2004). Seasonal surface water fluctuation can have profound effects on the physical, chemical and biological stability of a reservoir (Wetzel 1990). During the monsoon period, the lake water level increases due to rainwater intrusion from its large catchment area (Rouf et al., 2008). During the dry season the volume of lake water will decrease and these conditions have an effect on the dissolved oxygen, pH and temperature of the lake water.
Scientific management and conservation of lakes is overwhelmingly important in the milieu of predicted freshwater shortages in this new century, especially with the lowest per capita freshwater availability in the Asia-Pacific region (ILEC, 2007). Management and conservation programmes in lake, however, need baseline data and information. As such, the objective of this study was to determine the data on dissolved oxygen (D.O) (mg/l), pH and temperature (°C) of the lake water in Pengkalan Gawi – Pulau Dula section of Tasik Kenyir. These data are hoped to provide some useful information to agencies in managing and conserving Tasik Kenyir.

MATERIAL AND METHODS
Tasik Kenyir is the biggest man-made lake in Malaysia about 36,000 ha (Figure 1). The lake lies in the state of Terengganu at 4°47’N to 5°15’N and 102°32’E to 102°55’E. This man-made lake was initially impounded in 1986 to generate hydroelectric power, receiving water inputs from two main rivers – the Terengganu and Terengan rivers (Furtado et al., 1977). The lake has 340 island, located 145 m above the sea level with a mean depth of 37 m. It is a pleasant retreat for anglers and urban dwellers.
The study was conducted in one of the lake section named Pengkalan Gawi – Pulau Dula section of Tasik Kenyir (Figure 1). The study area was about 30 km2. Three stations were set up and designated as station A, which was located near Pulau Dula, Station B, which was located near Sungai Ikan and Station C, which was near Pulau Pupi.
This study was conducted for 11 months from March 2008 to January 2009. Water samples were collected in situ from each station and were collected using 1 litre acid washed polyethylene bottles. Water quality parameters for dissolved oxygen (D.O) and temperature (°C) were recorded using a portable dissolved oxygen meter model YSI 55 D.O. Meter. A portable pH meter model HACH EC 10 was used to determine pH in the lake water. All the data were analysed using one-way analysis of variance (ANOVA) and were processed using SPSS version 17.0 to measure the significant difference among sampling stations.
Figure 1: Tasik Kenyir in Terengganu is the biggest man-made lake in Malaysia and the square box shows the location of Pengkalan Gawi- Pulau Dula section of Tasik Kenyir.


RESULTS AND DISCUSSION
The water quality parameters of the lake were generally constant at each station every month. The data sets of the water quality were analysed from March 2008 to January 2009. Table 1 shows the water quality parameters during the sampling period. Throughout the study period the mean water temperature (29.76 °C ± 1.33) was in the range of natural environment temperature. Other parameters also had mean readings within the normal range; D.O (6.18 mg/l ± 0.49) and pH (6.91 ± 0.46) (Table 1). 
The results of this study showed some similarity with previous studies done by Verdegem (1999) and Yusoff and Ambak (1999) in Tasik Kenyir. Their studies found that temperature ranged from 24.2 to 30.6 °C, D.O readings from 3.50 to 8.90 mg/l and pH reading from 6.72 to 7.61 mg/l. Meanwhile, the results of this study showed that temperature ranged from 26.5 to 31.8 °C, D.O reading ranged from 5.01 to 7.90 mg/l ad pH reading from 6.25 to 7.96 mg/l (Table 1). From here we can predict that these three water quality parameters do not change much even after more than 10 years. In terms of stations, the water quality parameters showed no significant difference among stations except for pH readings (Tables 2). The pH reading in Sungai Ikan showed a significant difference of pH in Pulau Pupi. Pulau Dula meanwhile, showed no significant difference with both of the stations in terms of pH. The D.O and temperature showed no significant difference among stations. This indicates that Pengkalan Gawi – Pulau Dula section has a uniform reading of D.O and water temperature.   
The lake generally experiences heavy rain from the north-east monsoon from November to March and a hot and dry season from May to October (Ambak and Jalal, 1998). The monsoon season and the dry season effects the water quality parameters in this section. This is clearly shown in the monthly trends of water temperature, where it decreased from October 2008 to January 2009 (Table 3). Heavy rain during the monsoon season might results in a decrease in the temperature of the lake water.
Studies carried out by Kah-Wai and Ali (2001) in Tasik Chenderoh found that the mean water temperature at two sampling stations were at 27.40 °C ± 0.40 and 28.1 °C ± 0.60. These seem to be lower than the mean temperature of this study. In addition, Kah-Wai and Ali (2001) mentioned that due to the depth of Tasik Kenyir, it has a higher range of water temperature when compared to Tasik Chenderoh. Meanwhile, in Tasik Chini, Suhaimi-Othman and Lim (2006) recorded that the mean readings for water temperature, D.O and pH of the lake water were at 29.73 ± 0.44 °C, 6.08 ± 0.88 mg/l and 6.63 ± 0.24, respectively. These showed some similarity with the result of this study maybe due to the same ecological conditions of these lakes.


Table 1: Table shows the minimum, maximum and mean reading for different water quality parameters in Pengkalan Gawi- Pulau Dula section of Tasik Kenyir, Terengganu from March 2008 to January 2009.
Water quality parameters
Minimum
Maximum
Mean ± SD

D.O (mg/l)
5.01
7.90
6.18 ± 0.49

pH
6.25
7.96
6.91 ± 0.46

Temperature (°C)
26.50
31.80
29.76 ± 1.33


Table 2: Mean water quality parameters of the lake water at three sampling stations in Pengkalan Gawi- Pulau Dula section of Tasik Kenyir from March 2008 to January 2009. Mean ± S.D. within column with the same letters are not significantly different at (P < 0.05) level.
Stations
D.O
(mg/l)
pH
Temperature
(°C )

Pulau Dula (A)
6.18a ± 0.56
6.97ab ± 0.43
29.66a ± 1.17

Sungai Ikan (B)
6.27a ± 0.43
6.73a ± 0.37
30.15a ± 1.38

Pulau Pupi (C)
6.10a ± 0.49
7.03b ± 0.53
29.47a ± 1.40


Table 3: Mean water quality parameters of the lake water based on months at Pengkalan Gawi- Pulau Dula section of Tasik Kenyir from March 2008 to January 2009. Mean ± S.D.
 Months
D.O
(mg/l)
pH
Temperature
(°C )


March 2008
7.26 ± 0.39
7.45 ± 0.69
29.02 ± 0.27


April
6.55 ± 0.23
7.12 ± 0.68
30.80 ± 0.61


May
6.26 ± 0.09
6.78 ± 0.15
30.90 ± 0.63


June
6.25 ± 0.23
6.72 ± 0.19
30.52 ± 0.10


July
5.98 ± 0.03
6.54 ± 0.11
30.30 ± 0.23


August
6.03 ± 0.16
6.51 ± 0.08
30.03 ± 0.62


September
6.41 ± 0.08
6.81 ± 0.22
30.70 ± 0.38


October
5.67 ± 0.36
6.54 ± 0.08
30.88 ± 0.47


November
5.79 ± 0.49
6.90 ± 0.18
29.43 ± 0.08


December
5.86 ± 0.20
7.13 ± 0.33
27.68 ± 0.39


January 2009
5.98 ± 0.23
7.55 ± 0.09
27.08 ± 0.44




CONCLUSION
It can be concluded that the water quality parameters (D.O, pH and temperature) in Pengkalan Gawi – Pulau Dula section of Tasik Kenyir were still between the normal range that can support various flora and fauna inhabiting this lake section. Monitoring and sustainable lake managements are needed in order to maintain the lake water quality for future generations.
REFERENCES
[1]           Ambak, M. A. and K . C . A. Jalal (1998) Habitat utilization by the tropical fish community in the man-made Lake Kenyir, Malaysia. Fisheries Management and Ecology 1998, 5, 173-176. Blackwell Science Ltd.
[2]           Furtado, J., Soepadmo, I. E., Sasekumar, A. et al. (1977) Ecological effects of the Terengganu hydro-electric project (Kenyir project). Wallaceana (Suppl. 1), 51.
[3]           International Lakes Environmental Committee Foundation (ILEC) (2007) World Vision Action Report Implementing the World lake vision for the Sustainable Use of Lakes and Reservoirs. World Vision Action Report Committee, Shiga, Japan. 402 pp.
[4]           Kah-Wai, K. and Ali, A. B. (2001) Chenderoh Reservoir, Malaysia: Fish Community and Artisanal Fishery of a Small Mesotrophic Tropical Reservoir. 167-178. In: De Silva S.S. (ed.). 2001. Reservoir and culture-based fisheries: biology and management. ACIAR. Cornell University. Bangkok.
[5]           Moyle, P. B. and Cech, Jr. J. J. (2004) An Introduction to Ichthyology. Upper Saddle River, NJ: Prentice-Hall.
[6]           Rouf, AJM A., M. A. Ambak, Lokman Shamsudin, Siew-Moi Phang and Sinn C. Ho (2008) Temporal changes in the periphytic algal communities in a drowned tropical forest reservoir in Malaysia: Lake Kenyir. Blackwell Publishing Asia Pty Ltd. Lakes & Reservoirs: Research and Management 2008 13: 271–287.
[7]           Suhaimi-Othman, M. and E. C. Lim (2006) Eutrophic Condition at Tasik Chini, Pahang. Sains Malaysiana 35 (2) 2006: 29-34.
[8]           Verdegem, M. C. J. (1999) Lakes and reservoirs in Indonesia, Malaysia, the Philippines, Singapore and Thailand. In: W. L. T.
[9]           Wetzel, R. W. (1990) Land-water interfaces: Metabolic and limnological regulators. Int. Verein. Theor. Limnol. Verh. 24, 6–24.
[10]         Yusoff, F. M., Ambak, M. A. (1999) Trends and fluctuations in the environmental characteristics of surfacewaters inKenyir Reservoir. In: W. L. T. van Densen, M. J. Morris (Eds.), Fish and Fisheries of Lakes and Reservoirs in Southeast Asia and Africa. pp. 49–58, Westbury Publishing, Otley, UK.


This poster has won "the best poster presentation award" during the Symposium: 


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