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N ISSN: 0974 - 0376 Save Nature to Survive : Special issue, Vol. 1; 393- 399 QUARTERLY www.theecoscan.in WATER QUALITY PROFILING AND BIOMONITORING OF HATIA DAM Latika Sharan and Rekha Sinha KEYWORDS Biomonitoring Limnological profile Hatia Dam Paper presented in 3rd International Conference on Climate Change, Forest Resource and Environment (ICCFRE, 2011) December 09 - 11, 2011, Thiruvananthapuram, organized by Department of Environmental Sciences, University of Kerala in association with National Environmentalists Association, India www.neaindia.org 393 N Save Nature to Survive QUARTERLY LATIKA SHARAN AND REKHA SINHA Department of Botany, Ranchi Women’s College, Ranchi - 834 001 E-mail: [email protected] ABSTRACT Hatia Dam, an important drinking water source of Ranchi, has been investigated for physicochemical profile of water and biomonitoring has been done based on microphytic community. The results show that the water quality index (W. Q. I.) of the Dam is near to potability standard. The W. Q. I. was calculated to be 115.157 again normal value 100.00. The results of biomoniforing showed that the water body is oligotrophic in nature and there is no obvious pollution stress on the water body. The paper deals with different aspects of diversity indeces and assesses the status of the Dam. INTRODUCTION Biomonitoring is taken as a toolbox of techniques that can be used to keep a check on the integrity (or ‘health’) of aquatic ecosystems. Organisms that live their whole lives in water would not be present if conditions at any time during their lives had been too poor to sustain them. They can thus provide information on the environmental conditions that must have pertained in the water body since they were born. In contrast, chemical analyses provide accurate measures of the amounts of individual substances in the water, but this will reflect the conditions in the river only at the instant of sampling. Thus biomonitoring methods provide an integrated view of the state of an ecosystems and the quality of its water. Thus biomonitoring provides an appealing tool for assessment of aquatic pollution (Zhou, 2008; Sinha and Sharan, 2009; Sharan amd Sinha, 2010). Biomonitoring may be used within a planning and management framework to prioritize water quality problems for more stringent assessments and to document “environmental recovery” following control action and rehabilitation activities. Some of the advantages of biomonitoring for management over physico-chemical and other type of studies are that the biological communities reflect overall ecological integrity (i.e., chemical, physical, and biological integrity). Therefore, biomonitoring results directly assess the status of a water body (Sinha and Sharan, 2008). Further biological communities integrate the effects of different stressors and thus provide a broad measure of their aggregate impact. Communities also integrate the stresses over time and provide an ecological measure of fluctuating environmental conditions. From investment view point routine monitoring of biological communities can be relatively inexpensive, particularly when compared to the cost of assessing toxic pollutants, either chemically or with toxicity tests and lastly the status of biological communities is of direct interest to the public as a measure of a pollution free environment (Sharan and Sinha, 2010). Keeping the reliability, importance as well as the paucity of information pertaining to biomonitoring of aquatic systems of this region, the present work was taken up on biomonitoring of Hatia Dam coupled with it limnological profiling resuting nito assessment of water quality index. MATERIALS AND METHODS *Corresponding author Study area The experimental site Hatia Dam is located in the industrial campus of HEC, Hatia, Ranchi. The area of the water body is 3763600 m2 and average depth is approximately 11m. The study area experiences three distinct seasons i.e. summer, rainy and winter. The water body does not have any inlet bringing polluted water or effluent. The catchment area of the dam is comparatively clean and the water body does not receive agricultural run off. The water body used as drinking water source is the centre of water supply for a vast population of Ranchi. 394 WATER QUALITY AND BIOMONITORING the value of qi the more polluted will be the water with ith parameter. Physico-chemical analysis The analysis for physico-chemical characteristic of water was done following the standard method given by APHA (1960), Golterman (1969) and Trivedy and Goel (1984). The exceptions to equation (1) are the quality rating for two parameters viz. ph and dissolved oxygen, which require special calculation. The permissible range of pH is 7.0 – 8.5. Therefore, the quality rating equations becomes: qpH = 100 [(VpH 7.0)/(8.5 – 7.0)] ……….…………..(2) Where, VpH = Value of pH – 7, means simply the numerical difference between VpH and 7.0, ignoring its algebraic sign. Some of the parameters were analysed in the field while most of the parameters the samples were preserved using suitable preservative indicated by Trivedi and Goel (1984). The whole analysis was completed within 48h, A brief descrption is as follows: The air and water temperature was measured with an ordinary mercury thermometer with an accuracy of 0.1ºC. Equation (2) ensures that qpH = 0 for VpH = 7.0 The transparency was recorded as the depth upon which a Secchi’s disc was visible, when lowered in water or was taken out of water. pH was measured by using battery operated single electrode portable pH meter (Toshniwal Model CI – 47). The conductivity was determined by a conductivity meter (SYSTRONIX Model 3CI – 1). The situation is slightly complicated in case of dissolved oxygen, since, in contrast to other pollutants, the quality of water is enhanced if it contains more dissolved oxygen. Therefore, the quality rating qDO for this parameter has been calculated from the equation: ………….(3) qDO = 100 [(14.6/(14.6-5.0)-VDO/(14.6-5.0)] Where, VDO = values of dissolved oxygen. In equation (3), 14.6 is the solubility of oxygen (in mg/L) in distilled water at 0º and 5.0 mg/L is the standard for drinking water. Equation (3) gives qDO = 0 when VDO = 14.6 mg/L and qDO = 100 when VDO = 5.0 mg/L. The dissolved oxygen was determined by modified Winkler’s method (Welch, 1952; Odum, 1971). The free carbon dioxide and total alkalinity were obtained by titrating the sample against 0.1N hydrochloric acid and N/44 sodium hydroxide using methyl orange and phenolphthalein indicators respectively. Total suspended solids were estimated by reflexing the sample with potassium dichromatrically by developing a color with EDTA, sulphalinic acid and naphalamine hydrochloride sodium acetate. Biochemical oxygen demand was measured with the help of BOD incubator. It is well known that the more harmful a given pollutant, the smaller is its permissible values. So the ‘weights’ for various water quality parameters are assumed to be inversely proportional to be recommended standard for the corresponding parameters i.e. Wi = K/Si …………. (4) Where, Wi = unit weight for ith parameters. and K = constant of proportionality. The constant of proportionality is determined from the condition: 10 Σ Wi=1 …………. (5) i=1 For calculation of water quality index firstly subindex (SI) corresponding the ith parameter is determined. These are given by the product of the quality rating qi and the unit weight Wi of the ith parameter, i.e. (SI) I = qiwi …………. (6) The overall water quality index can be calculated by aggregating these subindices (SI) I linearly, which is presented as: 10 10 W.Q.I. = Σ (SI) i Σ wi i=1 i=1 10 = Σ qiwi ….…….. (7) i=1 Phosphate was analysed colorimetrically by ammonium molybdata – stannous chloride method and chlorides by titrating the sample against silver nitrate using potassium chromateas indicator. Calcium and magnesium were measured by EDTA method using murexide and erichrome black – T as indicator respectively. Water quality index The different parameter was again calculated following Ott (1978) and Lohani (1981) for water quality index of the water body. The water quality index was calculated by taking annual mean of recorded data and their standard values. The standard values (permissible values of various pollutants) for the drinking water, recommended by Indian Council of Medical Research (ICMR). Some standard values which were not available in ICMR standard were taken from the standards of United States public health services (USPHS), World Health organization (WHO) and Euoropean Economic Community (EEC). From observed values and standard values quality rating and weightage were calculated. The quality rating qi for ith water quality parameters (i = 1, 2……10) was obtained, in general, from the equation: qi = 100 (Vi/Si) ………….(1) where, Vi = Values of ith parameter Si = Standard of ith parameter Equation (1) ensures that qi = 0 when a pollutant (the ith parameter) is absent in water while qi = 100 if the value of this parameter is just equal to its standard value. Thus the large Biological analysis For phytoplankton population 10L of water was filtered through plankton net made up of bolting silk cloth (Trivedy and Goel, 1986). The plankton samples were collected from the dam near the surface between 8 to 10 a.m. for 12 months period from January to December 2007 on sunny days. Filtered phytoplankton samples were fixed and preserved in 4% formalin and the final volume was made to 10 mL by 395 LATIKA SHARAN AND REKHA SINHA addition of distilled water. The algae were identified using the keys provided by Prescott (1982), Desikachary (1959), Randhawa (1959), Gandhi (1967), Philipose (1967) and Gonzalves (1981). For counting phytoplankton a Sedgwick Rafter Plankton Counting Cell was used and algal population was counted as described by Trivedy and Goel (1984). The population data was expressed as no/L. temperature between 17. 0ºC to 30.0ºC. The value of transparency reading was maximum 65.30 cm in December’07 while the lowest value was recorded as 51.70 cm in April’07. As per pH values recorded during the present study the water body was found to be a bit alkaline. The maximum and minimum values of pH value in the year of study were 9.30 in November and 7.20 in September. Data analysis From the basic biological data various pollution indices like Shannon-Weiner index (Shannon and Weiner, 1949); Simpson index (Simpson, 1949); Hurlbert index (Hurlburt, 1971); Margalef index (Margalef, 1968) evenness component of the samples following Pielou (1966) were calculated to qualify the water quality of the water body. As presented in the Table 1 free carbon dioxide was not of regular occurrence in the water body. It was recorded only in five months of first year while in nine months of the second year. The free carbondioxide values was maximum in the months of August (3.20 mg/L) in year of study. The dissolved oxygen (DO) content of water ranged from 8.20mg/L (Maximum in December) to 4.80mg/L (minimum in August) during the period of study. The expected number of species under ideal condition of the habitat based on Broken Stick Model of Mac Arther (1957) was calculated following Lloyd and Ghelardi (1968) and the equitability component of diversity was calculated which is supposed to be very sensitive measure of environmental pollution or stress. Conductivity value ranged from a minimum value 0.38 mho in December’ 07 to a maximum 0.71 mho in June. As presented in Table 1 December 07 was the month when the lowest value of total alkalinity was recorded to be 98.20 mg/L and the highest value of the same was 200.80 mg/L in July. Carbonate content was low during the study and was not recorded in every month. Carbonate was found absent in January, February, June July, August, September and December. Carbonate content was maximum in June (33.08 mg/L) and minimum (3.50 mg/L) in November. The method applied during the present study is routine survey the various algal species occurring in the Dam, in order to evaluate the biological health, or biological integrity, of the resource surveyed. This type of survey is prepares the base of biomonitoring or biosurveying. Bicarbonate content was the main constituent to contribute to the total alkalinity content. It varied from 91.08mg/L to 188.20 mg/L – the minimum and maximum values recorded in December and July respectively. RESULTS AND DISCUSSION The data recorded on the various physico - chemical parameters of the Dam - water have been presented in different tables. Table 1 embodies the minimum and average values of different abiotc parameters observed during the years 2007. The total suspended solids were found in considerable concentration during rainy season. Phosphate is one of the most important nutrients for the water body and its concentration in water depends on the input from various sources. The minimum concentration of phosphate-P was 0.10 mg/L in the month of September and The air temperature on the days of experiment fluctuated from 18.20ºC (December‘07) to 32. 0ºC (June‘07) during year. The water temperature also fluctuated correlated with the air Table 1: The minimum, maximum and average ±SD value of different abiotic parameters of water of Hatia Dam during 2007 Parameter Minimum Maximum Mean ± SD Air temperature (ºC) Water temperature (ºC) Transparency (CM) pH Conductivity (mho) Dissolved oxygen (mg/L) Free CO2(mg/L) Total alkalinity (mg/L) Carbonate (mg/L) Bicarbonate (mg/L) Total suspended solids (mg/L) Phosphate (mg/L) Nitrate (mg/L) Silicate (mg/L) Chloride (mg/L) BOD (mg/L) COD (mg/L) Sodium (mg/L) Potassium (mg/L) Calcium (mg/L) Magnesium (mg/L) 18.20 Dec. 17.00 Dec. 51.70 Apr. 7.20 Sep. 0.38 Dec.. 4.80 Jul. 1.80 Jun. 98.20 Dec. 3.50 Nov. 91.08 Dec. 74.83 Nov. 0.10 Sep. 0.08 Jul. 0.87 Apr. 39.80 Sep. 1.86 Nov. 03.23 Jan. 41.60 Dec. 12.00 Oct 18.26 Nov. 10.62 Nov. 32.00 Jun. 30.00 Jun. 65.30 Dec. 9.30 Nov. 0.71 Jun. 8.20 Dec. 3.20 Aug. 200.80 Jul. 33.08 Jun. 188.20 Jul. 85.00 Aug. 0.26 Feb. 0.12 Jun. 1.82 Jun. 56.60 May 8.62 Jun. 8.29 Jun. 54.33 Jun. 19.00 Jun. 23.25 Mar 16.21 Dec. 26.216±5.054 24.716±4.783 58.950±5.381 8.583±0.641 0.510±0.118 6.341±1.277 3.780±1.669 149.258±32.682 13.820±9.735 141.333±28.243 73.888±18.173 0.110±0.157 0.212±0.153 1.181±0.274 72.866±7.983 4.664±2.238 6.865±10.444 41.260±9.165 16.583±2.353 18.240±3.928 12.456±1.428 396 WATER QUALITY AND BIOMONITORING Table 2: The Water quality index (W.Q.I.) of Hatia Dam during 2007 Parameter Standard Unit weight Wi Parameter subindex wiqi pH Alkalinity Hardness DO BOD COD Chloride Sodium Postassium Calcium Magnesium Total Solids 7.0-8.5 120.00 200.00 5.00 5.00 20.00 250.00 20.00 10.00 75.00 58.00 500.00 0.07164 0.00417 0.00167 0.10030 0.10030 0.02507 0.00200 0.02507 0.05015 0.00668 0.01003 0.00100 Σ wi = 0.32227 8.16690 0.55280 0.04258 7.32190 2.18210 6.96060 0.07233 2.31764 7.02100 0.16280 0.25300 0.05800 Σ wiqi = 35.11170 concentration, one of the important ions was 46.60 mg/L in December which was its minimal quantity. The highest value was 74.33 mg/L in June with average value 61.260 mg/L. Potassium is another important monovalent ion to be found in considerable concentration in water bodies. It was minimum in October (12.00 mg/L) and maximum in June (19.00 mg/L) with an average of 16.383 mg/L. It is an important divalent ion encountered in water bodies with considerable impact on water quality it was minimum in November (18.26 mg/L) and maximum in March (23.25 mg/L). Similar to calcium ion magnesium is also one of the important chemical constituents to be determined for water quality assessment. The lowest concentration of magnesium was observed in the month of November, the value being 10.62 mg/L and the highest concentration was in December (16.21 mg/L). N W. Q.I. =Σwiqi/ Σ wi = 115.15716 i=1 Based on the physic-chemical profile the water quality index was calculated and the value was found as 115.157. the highest value was 0.26 mg/L in February. In studies pertaining to assessment of health of water body from potability view point generally a number of physicochemical parameters are used and measured. Each of all these parameters depicts the condition of pollution separately in its own respect. But virtually no attempt has been made so far to obtain a result with regard to overall polluted condition. Nitrate is another most important nutrient and has been reported to influence the production of micro and macrophytes. Nitrate was found 0.12 mg/L as maximum value and 0.08 mg/L as minimum value in June and July respectively. The minimum and maximum value of silicate concentration in the study period were 0.87 mg/L and 1.82 mg/L in the month of April and June respectively. As an accurate and timely information on the quality of water in necessary to shape a sound public policy and to implement the quality improvement programmes efficiently one of the most effective ways to communicate information on water quality trends is with indices. A water quality index (W.Q.I. >100) may be defined as a rating reflecting the composite influence on overall quality, of a number of individual quality characteristics of water quality parameters. Moderate concentration of chloride content was observed during both the years of study. The maximum and minimum values in the year were 56.60 mg/L (May) and 39.80 mg/L (September). BOD is regarded as direct indicator of organic pollution as it increases or decreases with the level of sewage or organic pollutant load in water body. In general the unpolluted waters should be devoid of BOD and if present should be in very low quantity. The minimum concentration of BOD during the present study was 1.86 mg/L in the months of November while the maximum values were recorded in the month of June. The water quality index in other words quantifies the pollution level in physic-chemical terms. Following the method of water quality calculation some physico-chemical parameters were considered. The result after calculation have been presented in Table 2. 03.23 mg/L in January and 8.29 mg/L in June were the minimum and maximum and values recorded for chemical oxygen demand in the year. The value of W.Q.I. is slightly higher than the normal value. From this calculation on the basis of water chemical features the water body is still almost unpolluted but heading towards polluted condition. The monovalent and divalent ions play important role in determining the tropic status of a water body. The sodium It is well established that the plankton community, on which Table 3: Actual number of species, their abundance, expected number of species and their occurrence during 2007 in Hatia Dam Jan 2007 Feb 2007 Mar 2007 Apr 2007 May 2007 Jun 2007 July 2007 Aug 2007 Sep 2007 Oct 2007 Nov 2007 Dec 2007 No. of sp. found Total population S:N Minimum number Maximum number Expected no. of spices Equitability 26 26 34 35 34 43 19 18 25 41 16 18 91 89 114 124 143 140 81 50 82 152 48 49 0.285 0.292 0.298 0.282 0.237 0.307 0.234 0.360 0.304 0.269 0.333 0.367 0 0 0 0 0 0 0 0 0 0 0 0 55 57 59 72 71 63 56 25 45 85 22 20 12 11 13 12 15 13 10 12 11 15 12 15 0.461 0.423 0.382 0.342 0.441 0.302 0526 0.666 0.440 0.365 0.750 0.833 397 51.00% 51.00% 67.01% 68.71% 67.00% 84.41% 37.30% 35.29% 49.10% 80.39% 31.40% 35.29% 3.051269 0.762817 3.874767 0.767361 0.783688 3.33005 0.798587 4.368136 0.809663 0.826531 Nov 3.38194 0.631247 7.753357 0.739596 0.743871 2.989833 0.643826 5.446229 0.688281 0.696778 2.849275 0.670745 4.222696 0.724459 0.734809 3.140195 0.619455 8.547848 0.701257 0.705358 3.392416 0.666819 6.677942 0.733469 0.738746 3.001928 0.7199 4.345578 0.7336 0.748571 July June May 3.05698 0.595987 7.05353 0.656608 0.661946 3.150758 0.619318 6.823424 0.675989 0.681397 2.923 0.621859 5.82682 0.660912 0.670091 Apr Mar Feb Jan Shannon Weiner index 3.029458 Evenness 0.644505 Margalef index 5.416977 Simpson index 0.693069 Hurlburt index 0.7 Table 4: Variation in diversity indices of algal population of Hatia Dam in 2007 Aug Sept Oct Dec LATIKA SHARAN AND REKHA SINHA aquatic population depends, directly or indirectly, is largely influenced by the interaction of a number of physicchemical factors. The studies done on the microphytic community on the basis of application of different indices for the water body (Sinha and Sharan, 2008; Sharan and Sinha, 2010) the water body appears to be oligotrophic (Table 3 and 4). The Margalef diversity index is very important as it indicates the stability of the habitat. The higher diversity index values have been reported to be correlated with longer food chain and complex food web of the ecosystem and relatively more stable community (Margalef, 1968). In the present study the Margalef diversity index varied from 3.874 in November, 2007 to 8.547 in June, 2007. The range of variation in the index value is always in higher side. It proved that habitat is stable and organisms are not in stress. Pianka (1974) stressed on Simpson’s diversity index which is sample size dependent, reflects the proportional abundance of species richness and individual richness. Simpson’s diversity index varied from 0.660 to 0.809 in the month of February, 2007 and December, 2007 respectively. Mac Arthur (1965, 1972) explained the diversity variation on the basis of resources, resource utilization and niche overlap. Higher diversity values reflect diversified resources in the habitat available for components of the community. Decreased value of the species diversity indicated the increase of diversity of utilization of resources by an average species resulting into lowering of the number of co-existing species in the community. Apart from these two conditions the sharing of resources by species or the amount or extent of niche overlap supports more species and vice-versa. The Simpson’s diversity index varies between 0.660 to 0.809 in the water body. Hence the values more than 0.5 can be considered as higher values, thus following Mac Arthur explanation (1965, 1972) it can be concluded that habitat has diversified resources with higher diversity of their utilization by an averages species, providing a condition for co-existence of species as well as high amount of niche overlap i.e. sharing of resources among the co-existing species. The habitat is suitable for most of the algal species with no stress to any one. The niche overlap indicated high degree of coincidence of trophic preferences. A total of 51 species were recorded during the study. But the occurrence of species in a particular month was never more than 84.41% (June 2007). The minimum occurrence was 31.40% in the month of November 2007. Highest population density of planktonic algae was recorded as 152/L represented by 41 species while the lowest was only 48/L (November 2007) constituted by 16 species. The S: N (species number and individual number) ratio was calculated to be lowest as 0.234 (July, 2007) and highest as 0.307 (June, 2007). The expected number of species varied from a minimum of 11 species against 25 and 26 number of actual occurrence to a maximum, of 15 species against actual occurrence of 34 and 41 species. This data show that in ideal conditions the water body is suitable for lees number of species than what has been found. The equitability values ranged from 0.342 (April, 2007) to 0.833 (December, 2007). Based on Hurlbert (1971) index the diversity value obtained was more or less similar to those of Simpson’s value. The lower values of Hurlbert (1971) index may be explained as in the habitat there is high inter individual interaction i.e. high interspecific competition which has resulted into lowering of species diversity (Harman, 1972) and the higher values are found when the interspecific competitions are low, this can only be possible in the habitat when the resources occur in abundance for existing population. This ultimately coincides with the Mac Arthur’s explanation. The lowest Hurlbert’s index value was recorded in the month of February as 0.670 and the highest in December 2007 as 0.826. The range of variation is always more than 0.5 which is in higher side of the normal range of the index as it ranges between 0.0 to 1.0. Thus the habitat harbours species free from resource crunch and competitive pressure. A bimodal peak pattern was observed during the study which was in the months of May, 2007 and October, 2007. The post monsoon peak was bigger than the post winter peak. This may be due to the impact of accumulation of some nutrients brought in the water body from catchment area during rainy season. Shannon - Wiener index ranged between 2.849 (July, 2007) to 3.381 (October, 2007). This result according to the explanation of Wilhm and Dorris (1966) confirms slight pollution to no pollution state of the water body. According to the explanation of Staub et al. (1970), the water body under investigation is in the state of mild pollution (when Shannon Weiner index is less than 3) to unpolluted state. The species diversity (Shannon-Wiener index) and evenness of species or the evenness component of species diversity show no very apparent fluctuation. The more complex community, the greater is the species diversity and stability (Mac Arthur, 1965). Crude measure of stability of community over a given time can be obtained from the range of values of species diversity calculated within the time period. Thus the greater the fluctuation in the species diversity of a community, the less is stability. 398 WATER QUALITY AND BIOMONITORING 510-533. The range of expected number of algal species as shown in Table 3 is 10 to 15 and the range of equitability was calculated from 0.342 to 0.883in the months of April and December 2007 respectively. Mac. Arthur, R. H. 1972. Geographical Ecology: Patterns in the distribution of species. Harper and Row. New York. p. 269. Margalef, R. 1968. Perspectives in Ecological Theory. Univ. of Chicago Press. Chicago. p. 111. The equitability values calculated for the samples of the present study reflect that owing to “inequitability” the distribution of individuals among the species of the examined samplecommunity has a species diversity “apportioned” to a community of how many species as actually occur (Lloyd and Ghelardi, 1964). Odum, E. P. 1971. Fundamentals of Ecology. W. B. Saundess and co. Philadelphia. Ott, W. R. 1978. 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