HYDROGRAPHY OF THE FRESH WATER RESERVOIR NYARI-II OF RAJKOT DISTRICT, GUJARAT

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1 Electronic Journal of Environmental Sciences Vol. 5, 15 (2012) ISSN: (Available online at Original Article Indexed in: ProQuest database Abstract, USA ( ProQuest Science journals, Techonology Research database, Illustrata Technology, Environment Science collection and Health and Medical complete), EBSCO databases (USA), Indian Science abstract. HYDROGRAPHY OF THE FRESH WATER RESERVOIR NYARIII OF RAJKOT DISTRICT, GUJARAT GOSWAMI, A. P. 1 AND MANKODI, P. C. 2 1 Biology Department, M. V. M. Science and Home Science College, Rajkot , Gujarat. E. mail: arvindgirigoswami@gmail.com 2 Division of Fishery and Aquatic Biology, Department of Zoology, Faculty of Science, M. S. University of Baroda, Varodara Gujarat. E. mail: pcmankodi@yahoo.com Received: January 6, 2012; Accepted: January 30, 2012 Abstract: Nyari II reservoir is located in Rajkot district of Gujarat State near Rangpar village on Jamnagar road at Latitude: 22 o 21 45" N and Longitude: 70 o 40 15" E. The main purpose of construction of this reservoir is to provide water for irrigation in surrounding agriculture fields and drinking water to the Rajkot Urban Development Area. Limmnological study is one of the most important approaches to study the functional aspects of the fresh water bodies. The reservoir is influenced by several extrinsic factors which may alter the structural and functional components of such ecosystem. This study deals with the variation in the water quality from June 2006 to May The water samples were collected from the reservoirs for each month in the morning hours. Various physicochemical parameters like ph, temperature, alkalinity, hardness, chloride, dissolved oxygen, phosphate, nitrate etc. were analyzed. Significant seasonal variation was observed during the study for various parameters. Key words: Fresh water reservoir, Nyari II Rajkot? INTRODUCTION To overcome the problem of potable fresh water supply at local level, several minor irrigation projects were implemented resulting in to generation of extra surface water sheet. Such impoundments act as reservoirs. The reservoir itself maintains the hydrobiological status of its own by utilizing internal resources. Physical parameters for water quality such as turbidity, conductivity and water mass influence the chemical nature of the water. As it is evident that the quality of water plays a vital role in the chemical and organic status of the reservoir, therefore, it is necessary to check and maintain water quality standards through proper management strategies. The quality of water depends on its surface temperature, various gaseous as well as salt contents and other chemically linked biochemical factors [1]. A strong correlation exists among physico chemical properties, hence, a systematic calculation and interpretation of coefficient of correlation gives us an idea of rapid water quality monitoring [2]. 1

2 MATERIAL AND METHODS The study site is Nyari II fresh water reservoir constructed on Nyari river of Rajkot district, Gujarat State. Three water samples were collected randomly from various zones of the reservoir and were pulled together and final sample was drawn for the analysis. These samples were processed, preserved etc. for further detailed quality estimations in the laboratory. All the quality parameters were analyzed as per standard methods [3]. RESULT AND DISCUSSION Physical parameters: Physical characteristic of the water sample were estimated on the basis of standard methods. Surface temperature, turbidity, electric conductivity and solids were estimated, the results obtained are presented in table1. Surface temperature ranged from 21 C to 33 C in the reservoir throughout analysis period and, the average was recorded as C. The turbidity ranged from 2.5 NTU to 5.8 NTU, and the average was 3.96 NTU, the minimum turbidity was found in the month of August and maximum was in the month of May. Turbidity (3.96 ± 1.00 NTU) is comparatively higher than following year; also higher values were observed during premonsoon period may be due to more siltation trend [4]. The observations of electric conductivity (EC) ranged from 0.66 to 1.1 mho and average was Table 1: Physical parameters of water samples: Month Temp Turbidity Electronic Journal of Environmental Sciences E C TDS TS SS Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May mho. The minimum value was in October month and maximum was in the month of April. Higher values of EC in the month of May and June which may be attributed to higher evaporation rate leading to more concentration of salts in water samples which were collected from the periphery of the reservoir [5]. Similar observations were made for NyariII reservoir also. The solids in the water samples were estimated as Total Dissolved Solids (TDS), Suspended Solids (SS) and Total Solids (TS). Salts or solids in water are the indicators of active chemical nature whether suspended or dissolved. Hence, the estimation of total solids as well as dissolved and suspended solids was required. The Total Dissolved solids ranged from 436 to 732 mg/l, and average was 521 mg/l the minimum TDS was in October and maximum was recorded in the month of June. The total solids varied from to mg/l, and the average was mg/l, the minimum was in October month and maximum was in the month of June. The suspended solids ranged from 49.0 to mg/l, and the average was mg/l. Chemical parameters: Chemical characteristic of the water sample were estimated on the basis of standard methods. ph, gases like DO, Free CO 2, chloride, BOD, COD, Nitrate (NO 3 ), Phosphate (PO 4 3 ), Sulphate (SO 4 ), Total hardness (TH) and Total alkalinity (TA) were estimated, the results obtained are presented in table. The range of ph was 7.52 to 8.37, and the average was 7.84, the minimum ph was observed in July while the maximum was in the month of January. The ph was alkaline throughout the year. Various gases get dissolved from the atmosphere in the water of the reservoir through air water interactions. These gases plays very important role in sustenance of life and productivity of the reservoirs. Gases like Dissolved Oxygen, free CO 2, and Chloride were estimated from the water samples. The state of the dissolved oxygen ranged from 3.77 to 10.9 mg/l, and the average was 6.78 mg/l, the minimum DO was in August and maximum was in the month of January. The range of Free CO 2

3 Table 2: Chemical parameters of water samples: Goswami and Mankodi Month ph DO Free Chloride BOD COD NO 3 PO 3 4 SO 4 TH CaH MgH TA CO 2 Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Table 3: Interrelation between water quality parameters: ph Temp Turbidity E.C TDS SS TS DO CO 2 Cl BOD COD NO 3 PO 4 SO 4 TH CaH MgH ph TEMP Turbidity E.C TDS SS TS DO CO Cl BOD COD NO PO SO TH CaH 0.82 MgH between to mg/l, and average was mg/l, the minimum Free CO 2 was in August month and maximum was in the month of December. The minimum chloride was in the month of October and maximum was in the month of June with the range was 95.0 to mg/l, and average was mg/l. The range of BOD was to 9.71 mg/l, and average was 3.07 mg/l, the minimum BOD was in the month of June and maximum was in the month of May. The range of COD from 8.0 to 37.0 mg/l, and average was mg/l, the minimum COD was in the month of July maximum was in the month of May. The Nitrate range between to mg/l, and average was 0.29 mg/l, the minimum NO 3 was in December month and maximum was

4 in the month of November. The range of PO 4 3 from to 0.33 mg/l, and average was 0.14 mg/l, the minimum PO 4 3 was in the month of May and maximum was in the month of December. The range of SO 4 between 28.0 to mg/l, and average was 68.5, the minimum SO 4 was in the month of March and maximum was in the month of June. The range of Total Hardness (TH) was from to mg/l, and average was mg/l, the minimum Total Hardness was in October month and maximum was in the month of June. The range of Calcium Hardness (CaH) from 70.0 to mg/l, and average was mg/l, the minimum Calcium Hardness was in the month of October and maximum was in the month of June. The range of Magnesium Hardness (MgH) from100.0 to mg/l, and average was mg/l, the minimum Magnesium Hardness was in the month of December and maximum was in the month of June. The range of Total Alkalinity from to mg/l, and average was mg/l, the minimum Total Alkalinity was in the month of October and maximum was in the month of June. Generally primary productivity increases in winter months and decrease in summer months due to variation in temperature [6]. The importance of ph on aquatic life has been justified [7]. The alkaline ph has been considered good for the growth of flora in the reservoirs. The ph is considered as an important ecological factor and is the result of interactions of various substances in the water [8]. ph has positive relation with abundance of zooplankton [9]. Annual average of Dissolved Oxygen is 7.19 mg/ l recoded for year This level of oxygen is ideal for fish production [10]. The Dissolved Oxygen is regulated primarily by free diffusion of oxygen from air to water and produce through photosynthesis etc. As observed by As identical to conditions observed in different water sheets of Central India [11,12], we have observed low values of the dissolved oxygen during summer. Free carbon dioxide; however do not show any significant relationship with other physicochemical parameters, its absence is usual in Electronic Journal of Environmental Sciences unpolluted water body [13]. The higher concentration of free Carbon dioxide during April and May be attributed to variation in abundance of phytoplankton [1]. In fresh water reservoirs availability of chloride has less significance still notable higher values of the same has been observed during summer months in our study. This may be due to high evaporation rate; marginal high values recorded here for chloride may be cited as an index of its animal origin [11]. Chloride has represented highly significant relationship with hardness and alkalinity in the water samples collected from NyariII reservoir. No significant statistical difference was observed for COD values during two years of study, similar to Mustapha observation [14]. Nutrients in the form of Nitrate (NO 3 ), Phosphate (PO 4 3 ) and Sulphate (SO 4 ) exhibit marginal variations in their annual averages for both the years; monthly variation is more for the entire year. Sulphate is statistically observed with high value of standard deviation. The high value of Sulphate during summer season and attributed it to the high temperature and higher rate of evaporation, similar condition has been observed in present study for the month of April to June [15]. The phosphate value changes probably due to influx through rain water [11]. Lower values of alkalinity during monsoon are obviously due to dilution of the reservoir water through new water entry [16]. The water bodies having total alkalinity more than 200 mg/l are highly productive in nature [17]. The desirable value of 100 mg/l of total alkalinity coincide with the observations made for the entire years from the samples of Nyari II reservoir, indicates that the water is productive and will have higher trophic status [18]. The status of interrelationship between various water quality parameters in presented in table 3. Salts in water represent various degree of significance with electric conductivity, chloride content and various forms of hardness. However, no other parameters were having significant relationship between them to ascertain their influence on each other. 4

5 Goswami and Mankodi ACKNOWLEDGEMENTS The authors are thankful to The Head, Department of Zoology, The M. S. University of Baroda, Vadodara to provide necessary laboratory facilities to carry out this work in the department. One of the authors, Goswami, A.P. is thankful to the Principal, Shree M.V. Mahila Science and Home Science College, Rajkot for the permission to carry out this research work. REFERENCES [1] Kumar, R. and Kapoor K.: J. Environ. Ecoplannning, 12: (2006). [2] Arvinda, H.B., Manjappa, S. and Puttaiah, E.T.: Poll Res., 17: (1995). [3] APHA, Standard Methods for the Examination of Water and Waste Water. 20 th Edn. American Public Health Association, Washington D (1998). [4] Kumar, R.A.V., Lingaiah, A.M.S., Rao, S. and Piska, R.: J. Aqua. Biol. 22: (2007). [5] Hujare, M.S. and Mule, M.B.: J. Environ. Ecoplannning, 14: (2007). [6] Korai, A.L., Sahato, G.A., Lashari, K.H. and Arbani, S.N.: Turkish J. Fisheries Aquatic Sci., 8: (2008). [7] Welch, P.S.: Limnology. Mc. Graw. Hill Book Co., New York, pp 538 (1952). [8] Tamlurkar, H.L. and Ambhore, N.E.J.: Aqua. Biol., 21: (2006). [9] Bhandarkar, S.V. and Gaupale, D.T. J.: Curr. Sci., 17: (2008). [10] Banerjee, R.K. and Babu Lal: Technologies for inland fisheries development. (Sagunan, V.V. and Utpal Bhaumik eds), Central Inland Capture Fisheries Research Institute: Barrackpore West Bengal. pp (1990). [11] Munawar, M.: Hydrobiologia. 31: (1970). [12] Pawar, S.K., Mane, A.M. and Pulle, J.S.: J. Aqua. Biol., 2: 5558 (2006). [13] Sharma, K.P.: J. Ecol. Enciron. Sci., 4: (1978). [14] Mustapha, M.K.: Rev. Biol. Trop. (Int. J. Trop. Biol. ISSN ), 57(4): (2009). [15] Kulkarni, S.D., Mokashe, S.S. and Patil, R. P.: J. Aqua. Biol., 10: 213 (1995). [16] Mishra, G..P. and Yadav, A.K..:. Hydrobiologia, 59: (1978). [17] Moyle, J.B.:. Amer. Midi. NaH., 34: (1946). [18] Sarwar, S.G. and Wazir, M.A.: Poll. Res., 10: (1991). 5