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Volume

Volume 2

RAJSHAHI UNIVERSITYJOURNAL OF ENVIRONMENTAL

SCIENCE

ISSN 2227-1015

December

2012

Institute of Environmental Science (IES)University of Rajshahi

Rajshahi‐6205 BANGLADESH

Rajshahi University Journal of Environmental Science

ISSN 2227-1015

Volume No. 2, December, 2012

IES Publication No. 2

Published by

Institute of Environmental Science University of Rajshahi

Rajshahi-6205, Bangladesh www.ru.ac.bd/ies

@ All rights reserved by the publisher. The Journal is published yearly accommodating all aspects of environmental science both experimental and theoretical within the available scope after peer review.

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Institutions: Inside Bangladesh Tk. 500 per copy Out side Bangladesh US$ 50 per copy Individual: Inside Bangladesh Tk. 300 per copy Out side Bangladesh US$ 30 per copy Correspondence: All correspondence should be addressed to the Editor, Rajshahi University journal of environmental science, Institute of Environmental Science, University of Rajshahi, Rajshahi-6205, Bangladesh Website: www. ru.ac.bd/ies, e-mail: [email protected], Tel. 880-0721 750930

Cover Design Dr. Md. Redwanur Rahman Printed at: Rajshahi University Press

ISSN 2227-1015

RAJSHAHI UNIVERSITY JOURNAL OF ENVIRONMENTAL SCIENCE

A Yearly Journal of the Institute of Environmental Science

Vol. 2 No. 2 December, 2012

EDITORIAL BOARD

Chief Editor Professor Dr. Md. Sarwar Jahan

Members Professor Dr. Raquib Ahmed Professor Dr. Zahidul Hassan Professor Dr. Md. Golam Mostafa Dr. Md. Abul Kalam Azad Dr. Md. Redwanur Rahman

Associated with us : Zakia Yasmin and S.M. Shafiuzzaman

Published by- Institute of Environmental Science, University of Rajshahi Rajshahi-6205, Bangladesh e-mail: [email protected] Tel. 880-0721-750930 Office : Saheen Ackter Jahan

FOREWORD

Environment, may be described as the sum total of every thing around us which regulates our life on earth, always tends to remain in a dynamic state of balance but the human beings are unscrupulously deteriorating the prevailing balance through different forms of intervention into the environmental requisites at every moment for irrational life style and indiscriminate action. As a result natural calamities like changes in the climate, global warming, drought, air pollution, water pollution etc. are frequently occurring and threatening human life and life supporting systems. This fact leads us to study the existing and changing modes of various environmental components, their interactions with and consequences of the anthropogenic activities on them and taking effective measures for replenishing environmental sustainability. The Institute of Environmental Science (IES), Rajshahi University was established in 1999 to focus on the weapons to study, explore and solve the environmental problems in Bangladesh for sound and safe environment. Quality higher education and research in different aspects of environment and related fields of knowledge are being conducted in the institute properly. The Institute publishes ‘Rajshahi University Journal of Environmental Science’ to disseminate the knowledge generated through research programmes in the institute along with scientific writings in the field of environment by other devoted researchers from home and abroad.

Unfortunately, in spite of all sincere efforts we could not publish the second volume of the journal timely due to some unavoidable circumstances. Nevertheless it’s our satisfaction that the issue is going to be published with some good peer reviewed articles reflecting diverse themes and objectives for sustaining environment for human existence on the globe. We are grateful to the distinguished reviewers who helped us to review the articles of the contributors. We cordially invite suggestions for improving the quality of the journal.

I wish this effort will continue and enable us to contribute in disseminating explored knowledge and build up public awareness to modify or keep the environment within the limit of tolerance so that it can have the required equilibrium for healthy living of the present and future generations.

Editor

INSTRUCTIONS TO CONTRIBUTORS

Manuscripts: The manuscript must be sent in MS Word Document file format. The manuscript should contain title of the paper, name and address of the author(s) and authors’ affiliation. Abstract should be within 250 words along with maximum of 5 key words indicating only the objectives and precise results or conclusion of the study. The text of the full paper should preferably be within 5000 words. A full paper should have the following sub-titles:

o Introduction: Introduction should be concise and precise relevant to objectives of study. o Materials and Methods: Standard and published methods should not be described rather

only be cited as references. Any modification or new set up should be stated. o Results and Discussion: Results should be presented with appropriate figures, tables and

graphs. If result is given in the body of the text, table is not necessary and vice-versa. If table is given no graph is needed and vice-versa followed by critical discussion.

o Tables, Graphs and Figures: The paper should contain maximum of 12 tables, graphs and figures all together. Figures, graphs and photographs should be given as attached file along with appropriate marking numbers in standard BMP format (uncompressed).

o Acknowledgements, if any: o References: The following format may be followed. 1. Format Instructions 1.1. Instructions for typists

Margins are to be set to a width of 15.2 cm, and each page must be typed in Times New Roman 11 points letter for the main text with a 13 points spacing between the lines. The footnotes to be typed in Times New Roman 10 points letter with an 11 points spacing between the lines. Each page must be typed in a page depth of 21.6 cm. On the first page, the title of the paper should start after three blank lines below the journal heading. The headings used are:

2. First-Order Headings These should be typed in bold, upper- and lower-case letters, with two lines space above the heading, and one line space below. The text after the heading will begin at the left-hand margin (i.e., it will not indented as for new paragraph).

2.1 SECOND-ORDER HEADINGS These should be typed in bold italics with a capital initial, at the left-hand margin. As before, there will be one line space above, and one line space below the heading. 2.1.1. THIRD-ORDER HEADINGS These should be typed in plain italics with a capital initial, at the left-hand margin. There will be one line space above, but no line space below the heading.

New paragraphs should be indented 3 blank spaces from the left margin, with no blank space between the paragraphs.

Special Attention 3.1. Tables Skip one line above and below tables. If table heading extends over one line, continue on the second and following lines immediately below the first letter of the heading. Do not use full stops at the end of the heading. Use horizontal lines above tables, below column headings, and below tables. Use capitals for the first letter of column headings. As far as practicable, arrange the tables in the vertical direction just as in text. Tables and text may appear on the same page. Table 1 is an example of an acceptable table format.

Table 1 Example of a legible table Quarter Direction

First Second Third Fourth East West North

20.4 30.6 45.9

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90.0 34.6 45.0

20.4 31.6 43.9

3.2. Figures Skip one line above and below figures. Place figure captions at the bottom of the figures and leave one line of spacing between figures and captions. Do not use full stops at the end of figure captions. Start second and subsequent lines immediately below the first letter of the caption. Skip one line after caption. Figures and text may appear on the same page. Legends, scales, etc. must be large enough to be legible. Give the consecutive numbers for tables and figures, respectively. Figures have to be placed above or below of a page. You can break a paragraph in case of placing a figure. Try to avoid blank spaces within the text.

3.3. Equations Equations should be numbered sequentially as follows. Use 1 line spacing instead of a 13 points spacing for the lines from just above to just below the equation. 02 =∇ φ (1) 3.4. References In the text, author’s last name should be followed by the year of publication; e.g. “it has been demonstrated (Suh et al., 1997) that …” or “Choi (1998) showed that …”. In the list of references, arrange authors’ last names in alphabetical order with 0.5 cm indentation for the second and following lines of each reference. When two or more references by the same author are listed, the earlier work should appear first. All references must be cited in the text. Journal: Rahman, M.R. and Jahan, M.S. 2006. Trematode Parasites of Freshwater Gastropods. Bangladesh

J. Zool. 34(1): 13-34. Jahan, M.S, Islam, M.R and Rahman, M.R. 2007. Ecology of Pila globosa (SWAINSON 1822)

(Gastropoda: Prosobranchia) in Bangladesh. Bangladesh J. Zool. 35(2): 341-355. Book: Blanford, W.T. and Godwin-Austen. H.H. 1908. The Fauna of British India, including Ceylon and

Burma, Mollusca: Testacellidae and Zonitidae: Taylor and Francis, London. 311p.

Book chapter: Cutrona, C.E. and Russell, D. 1990. Type of social support and specific stress: Towards a theory

of optimum matching. Sarason, I.G. and Sarason, B.R. (Eds). Social Support: An Interactional view 341 - 366

Book edited: Kumar, A. and Bidha, D. (Eds) 1989. Toxicology. (Kathmundu: Tribhuban University Press), 525p. Dissertation/Thesis: Rahman, M.R. 2000. Freshwater Gastropods in Relation to Helminth Parasites of Bangladesh.

Ph.D. Dissertation. University of Rajshahi, Bangladesh, 164p. Report: WDATCP (Wisconsin Department of Agriculture, Trade, and Consumer Protection) 1991. Report

to the state legislature: Agricultural clean sweep demonstration projects, Madison, WI: Agricultural Resource Management Division.

Regulation: USEPA (United States Environmental Protection Agency) 1995. Water quality standards-

Revision of metals criteria, Fed. Reg. 60, 22229-222237. Proceedings: Krewitt, W., Trukenmueller, A., Mayerhofer, P. and Freidrich, R. 1995. An integrated tool for

environmental impact analysis. In: Kremers, H.; Pillmann, W., eds. Space and time in environmental information systems, 90-97.

Online published articles with DOI (with /without page no): Mutton, D., Haque, C.E. 2004. Human Vulnerability, Dislocation and Resettlement: Adaptation

Processes of River-bank Erosion-induced Displaces in Bangladesh. Disasters, Volume 28, Number 1, March, pp. 41-62(22).

http://www.ingentaconnect.com/content/bpl/disa/2004/00000028/00000001/art000, 03;jsessionid=2hcpbncdhmb3r.alice?format=print.

Incase of short communications there is no need for subtitle, but reference may be listed as usual.

One hard copy of the journal will be sent to the corresponding author by surface post. Declaration: The cover letter of a manuscript must include a declaration indicating that (i) the work reported has been carried out by them and they jointly prepared the manuscript; (ii) they take public responsibilities for the contents of the paper; (iii) the paper has not been published or submitted to any referred scientific journal for publication. Address of the journal:

The Editor Rajshahi University journal of environmental science Institute of Environmental Science University of Rajshahi Rajshahi-6205 Bangladesh E-mail: [email protected]

ISSN 2227-1015

RAJSHAHI UNIVERSITY JOURNAL OF ENVIRONMENTAL SCIENCE

Vol. 2 No. 2 December, 2012

CONTENTS

Articles Page Evaluation of The Environmental Pollution Due To Uranium in Water of The Northern Part of Bangladesh and Adverse Effect in Health and Agriculture- M. S. Khatun, M. R. Rahman and M. A. Hossain

1-11

Evaluation of Groundwater Salinity and Arsenic Contamination and Its Environmental Impact in Shyamnagar Thana of Satkhira District, Bangladesh-S.M. Shafiuzzaman

12-22

Analyses of the Pre and Post Farakka Rainfall and Water Discharge Pattern of the River Ganges (Bangladesh portion) and Its Impact on Environment- Md. Nizam Uddin Shaikh, M.G. Mostafa, Md. Abu Hanif Sheikh and Md. Zahidul Hassan

23-34

An Assessment of the Changing Pattern of Seasonal Rainfall due to Climate Change over Rangpur District in Bangladesh- Md. Zakaria Hossain, Md. Abul Kalam Azad, Samarendra Karmakar and M. A. Haque

35-44

Agricultural Vulnerability to Climate Change Induced Sea Level Rise and Options for Adaptation: A Case Study of Shyamnagar Upazila- Md. Anowarul Islam, Shitangsu Kumar Paul and Md. Zahidul Hassan

45-59

Knowledge Attitude and Practices Regarding Pesticide Use in Vegetable Cultivation and Marketing in Bangladesh- Kazi Muhammad Wazir Hyder and Md Al Mamun Sarker

60-68

Toxicity of Derris indica Bennet. extracts against the larvae of Tribolium castaneum (Herbst)- Omar Ali Mondal, KAMSH Mondal and Nurul Islam

69-74

Changing Sustainability Scenarios in Bangladesh: The Synergies of the Physical and Non-physical World- Amzad Hossain and Dora Marinova

75-86

Constraints Faced by the Farmers in Betel Leaf Cultivation: A Case Study in Rajshahi District- M.K. Hossain, M.M. Rahman, A.K.M.K. Pervez and A.B.M. Sharif Uddin

87-95

Medicine From Earthworms Extract: A Clinical Study on Rheumatic Fever Patients- Md. Sarwar Jahan, Md. Mijanur Rahman and Md. Redwanur Rahman

96-107

EVALUATION OF THE ENVIRONMENTAL POLLUTION DUE TO URANIUM IN WATER OF THE NORTHERN PART OF BANGLADESH AND ADVERSE

EFFECT IN HEALTH AND AGRICULTURE

M. S. Khatun1, M. R. Rahman2, M. A. Hossain* 1Training Institute, Atomic Energy Research Establishment (AERE), Atomic Energy Commission, Saver, Dhaka.

2Institute of Environmental Science, University of Rajshahi, Rajshahi-6205, Bangladesh.

Abstract

Natural uranium enters into human bodies mainly through drinking water and food-chain when ground water is used for food-production. In this work the range of uranium content was found to be 3.48±0.23 to 47.12±0.47 µgL-1 in different districts of northern part of Bangladesh. The uranium concentration in ground water of northern part of Bangladesh namely Nawabgonj and Rangpur districts exceeds the range of MAC (Maximum Acceptable Concentration) levels (30 µgL-1) of uranium in drinking water.

Key words: Uranium, Health hazard, Ground water, Radiation Dose. 1. Introduction Uranium, the most abundant of the radioactive elements in natural mixture consists of three different isotopes, viz. 238U (about 99.3%), 235U (about 0.7%) and a trace quantity of 234U (about 5x10-6 %). The 238U and 234U comprise the uranium series, while the 235U isotope in natural uranium forms the first member of another series known as the actinium series (Cember, 1989). Only a very small part is from the settling of uranium dust out of the air. Some of the uranium is simply suspended in water, like muddy water (Singh et al., 1993). The amount of uranium that has been measured in drinking water in different parts of the United States by EPA (Environmental Protection Agency) is generally less than 1.5 µg (1 pCi) for every liter of water (USEPA, 1990; 1991; 1992).

Groundwater is an important natural resource for most parts of the world. It is often the primary source for domestic and industrial water supply besides its growing demand for agriculture. Uranium enters into human tissue mainly through food and drinking water. Water having uranium concentration above the proposed Maximum Acceptable Concentration (MAC) is not safe for drinking purpose as it occur lead to harmful health effects in humans. Uranium in drinking water is covered under the Federal Safe Drinking Water Act. Current standards of uranium for drinking water by ingestion are:

(i) WHO provisional guideline for drinking water quality: 15 µg of uranium per liter: This value is considered to be protective for sub-clinical renal effects reported in epidemiological studies. It is based on the assumption of a 60 kg adult consuming 2 liters of drinking water per day and an 80% allocation of the TD1 to drinking water. This value supersedes the earlier 2 µg/l provisional guideline, which was based on only 10% allocation of the TD1 to

* Corresponding author, Department of Physics, University of Rajshahi,Rajshahi-6205, E-mail: [email protected]

ISSN 2227-1015Rajshahi University journal of environmental science, Vol. 2, 01-11, December 2012

Evaluation of the Environmental Pollution due to Uranium in Water Khatun et al.

2

drinking water and the 9 µg/L provisional guideline, which was based on 50% allocation of the TDl to drinking water (WHO, 2003).

(ii) Health Canada: Interim maximum acceptable concentration (IMAC) for uranium in drinking water: 20 µg per liter (Health Canada, 2002).

(iii) Australian Drinking Water Guidelines: The concentration of uranium in drinking water should not exceed 20 µg per liter (ADWG, 1996).

(iv) USEPA - Rule on Radiomiclides in Drinking Water: Maximum contaminant level for naturally occurring uranium 30 µg per liter. EPA determines a safe level of 20 µg per liter, assuming that an adult with a body mass of 70 kg drinks 2 liters of water per day and that 80% of exposure to uranium is from water. For cost considerations, however, EPA established a standard of 30 µg per liter rather than 20 µg per liter (USEPA, 2000).

Natural uranium enters into human bodies mainly through drinking water or through food-chain when ground water is used for food-production. Radon, a decay product of uranium, is the 2nd leading cause of lung cancer after cigarette-smoking. Uranium is a weak chemical poison that can seriously damage kidneys at high concentration in blood. Major health hazard of uranium in the body is renal failure. Origin of most of these diseases is linked to hypertension and diabeties but it is imperative to say that dissolved uranium in drinking water may also contribute at least a fraction to this fatal disease. Various studies suggest that, there is a correlation between increased incidences of lung cancer with high radon activity. In fact, the daughters of radon gas cause injuries to the inner wall of lung. As the half life of radon gas is high, it is inhaled and exhaled without causing any direct problem of health. By inhalation, the daughter of radon gas is deposited in the inner wall of lung. These short-lived daughters emit alpha particles, which damage the lung cells. Thus, radon and its daughters are considered as health hazards (Hartley, 1983; Nero and Lowder, 1984). All 71 groundwater samples from Bualda, Fulbaria, Jamjami, and Komlapur were analyzed for every toxic element that has ever been found to exceed WHO health-based guidelines in Bangladesh’s drinking water: As, B, Ba, Cr, Mn, Mo, Ni, Pb, and U (BGS/DPHE 2001; Frisbie et al. 2002). It has been mentioned earlier that radiation is harmful to man and environment. Thus it is important to make studies on the distribution of various radionuclides present in the environment and the different factor influence the uptake of these radionuclides from soil to food-chain and their subsequent transfer to human body. The main objective of the present study is to measure the concentration of radionuclides in the environment for the assessment of population exposure. Under the limited scope of thesis research, we have selected nine districts namely Rajshahi, Naogaon, Nawabgonj, Sirajgonj, Pabna, Joypurhat, Dinajpur, Bogra and Rangpur from Northern part of Bangladesh. Hence, the main objective of this study was to measure the concentration of Uranium in drinking water of different districts of northern part of Bangladesh with a view to assess effective dose due to intake of these radionuclides through direct consumption of drinking water.

2. Materials and Methods 2.1 STUDY AREA We have selected nine districts viz., Rajshahi, Naogaon, Nawabgonj, Sirajgonj, Pabna, Joypurhat, Dinajpur, Bogra and Rangpur from NW part of Bangladesh (Map 1).


3

2.2 COLLECTION OF WATER SAMPLE For limited scale mapping of uranium concentration across the geographical region of NW part of Bangladesh, a total of 81 ground water samples were collected from 9 districts namely, Rajshahi, Naogaon, Nawabgonj, Rangpur, Sirajgonj, Dinajpur, Bogra, Joypurhat and Pabna. Samples were collected in fresh plastic bottle of 100 ml capacity from hand tube well during October 2006--January 2007 and June 2007- September 2007. All samples have been collected following an appropriate Water Sampling Procedures (EST, 1987). When water samples are collected for analysis, care has been taken to ensure that there is no external contamination of the samples. Unless valid samples are collected, the results of the subsequent analysis may be misleading. 2.3 GROUNDWATER SAMPLE ANALYSIS All the collected groundwater samples were analyzed using calibration methods. Background correction was performed using the blank test detector. One set of blank detectors were used to determine the tracks already existing in the detector surface. The blank detectors were directly etched without any exposure. These detectors were scanned under microscope and used as blank track densities and subtracted from the groundwater sample data. These corrected data was used to determine the uranium concentration of the groundwater sample. Blank track densities measured for the current set of detectors are given in Table 1. All the detectors were chemically etched and scanned under optical microscope for obtaining the track densities. Tracks in each exposed detector were counted for known areas. Using the number of tracks, track density was calculated for all the detectors. Then background correction was performed. This was done simply cancelling background track density from the original data. Then the corrected data was used to determine the uranium concentration of the groundwater sample. 2.4 EXPERIMENTAL PROCEDURE (i) Instruments used in the present work: The following equipments and reagents are used in

the present work such as, CR-39 detector, Constant temperature water bath, Optical microscope, 6N NaOH, weight box, beaker, distilled water, micropipette, thermometer etc.

(ii) Experimental arrangement for the detectors: CR-39 plastic detectors were prepared by cutting 0.25 mm thick CR-39 plastic sheet into small square shape pieces of size 1cm X 1cm with an anticutter. Identification number was engraved on each element in Arabic numerals for using them as SSNTDs (Solid State Nuclear Track Detector).

(iii) Calibration method: It is known that alpha particles emitted from uranium interacts with the SSNTDs and produce tracks and the alpha track density is proportional to the uranium concentration. To establish the relationship between uranium concentration (in ppb) and alpha track density standard uranium solutions having concentration of I1.30, 28.58, 56.75 and 109.4 ppb were obtained from Chemistry Division of Atomic Energy Center, Dhaka, Bangladesh Atomic Energy Commission (BAEC). In the present work 50µl of standard uranium solution was dropped on the detector surface using a micro pipette and dried in a vacuum chamber. The dried solution developed a thin film on the detector surface. Four detectors were exposed with four different standard uranium solutions. One detector was exposed with 50µl of distilled water. This blank detector will be used to detect any previous or natural exposure which may act as the background for exposed detector with standard solutions. The background track density would be subtracted to obtain tract density. Then the five detectors were exposed in airtight environment for two weeks free from any disturbance. After the exposure all of the detectors are taken out and washed with distilled


4

water for several times. After washing the detectors were dried in room temperature and marked. Then the detectors were kept for etching.

(iv) Track etching system: In the present study the optimum etching condition has been used for the CR-39 in a solution of 6 N NaOH at 70 °C over a 4 hour period. To achieve a fixed temperature of 70°C, a constant temperature water bath was used, to prepare a solution of 6 N NaOH, 24 gm of NaOH granules were added to a 100 ml volumetric flask. 10 ml of distilled water was added and shaken until NaOH granules were dissolved. Now carefully more distilled water was added until the volume of the solution was precisely 100cc. A beaker was filled three fourth of its volume with 6 N NaOH. The beaker was then placed in the water of the water bath and the mass of the solution inside the beaker was just sufficient to keep the beaker settled in the water bath without floating. The water bath was switched on and the temperature of water as well as the temperature of the solution gradually attained a fixed temperature of 70°C. The detectors to be etched were previously detached from the standard solution and kept inside paper envelopes, so that no new alpha tracks were registered before etching. For immersing a detector in the beaker and to let it stand at the bottom of the beaker each detector was fixed with a paper clip properly. Four detectors were dropped at a time in the solution of the beaker at 70°C. Beaker was covered with a glass lid, so that concentration of solution does not changes due to evaporation. After etching of precisely four hours, detectors were picked out of the beaker and dropped in cold water, hold under flow from top with the help of a forceps for two or three minutes. After this, detectors were finally washed in distilled water soaked by tissue paper, dried in air and then kept wrapped in tissue paper for subsequent study under a microscope. Similar procedure of etching and identical etching conditions were adopted for all the detectors. Particular care was taken to keep the concentration of the solution, the temperature and the period of time.

The central portion of the detector was scanned using a binocular research microscope at a magnification of 400X (40X objective and 10X eyepiece). Uncertainties arising in the nuclear measurements may a fleet the precision or accuracy of the analysis of any real sample. Precision refers to the reproducibility of the analysis of the replicate samples, while accuracy means the degree of agreement between the results obtained from any measurement and true or accepted concentration value. The counting statistics and background depends on the relative concentration of the element present in the sample and the detector integrity before used by Robert (1985).

The plastic sheet of CR-39 were preserved within paper cover properly so that it was not exposed to outside air or any other sources which might emit alpha particles. The sheets may somehow be exposed to alpha particles, before it is actually used for exposure. This may give to background counts which will be added to the actual number of tracks caused by the source under study. Thus background correction is important for present work. To do this, blank detectors were exposed under similar condition as the actual experiment but with distilled water. After etching tracks were counted in known areas and these background tracks were subtracted from the experimental counted track density. A linear relation has been obtained where the R2 value is 0.9978. The first order fitted equation is y = 0.0007X±0.4348, Here x values are track density and y values are uranium concentration in ppb.

Uranium concentration in the ground water sample has been calculated directly from the calibration curves. In the present research work calibration curve has been established from following equation, y = 0.0007X±0.4348 (Figure-1). This equation is similar to the equation, y = mx + c.


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3. Results and Discussion 3.1 URANIUM CONCENTRATION IN WATER SAMPLES OF NORTHERN PART OF BANGLADESH In the present work uranium concentration in water from different district of northern part of Bangladesh has been determined by using Solid state Nuclear Track Detector SSNTD (CD-39). The alpha track density has been measured using CR-39 plastic detectors. These densities are then used to determine the concentration of uranium in water. Uranium contents of different water samples have been obtained from the calibration curve and the concentration varied from 3.48±0.23 to 47.12±0.47 µgL-1. The lowest value 3.48±0.23 was found at Niamutpur of Naogaon district and highest value 47.12±0.47µgL-1 was obtained at Rohanpur of Nawabgonj district. The district average uranium concentration is shown in Table-2. The average district highest value 44.18±2.71 µgL-1was obtained in Nawabganj district and lowest value 4.78±0.52 µgL-1was obtanied in Naogaon district respectively.

The present results of the data have been highlighted in the Bar graph through figure-2. Figure -2 represents the map of Bangladesh showing the geographical locations of sampling sites as well as uranium concentration shown by colour. There are four identification colours. Blue colour represents uranium concentration from 0-10µgL-1, green colour represents from 11-20µgL-1, brown colour represents from 21-30 µgL-1 and red colour represents above 30 µgL-1.

3.2 COMPARATIVE STUDY OF URANIUM CONCENTRATION IN WORLD The results of this study have been compared with the uranium concentration in water samples of the other places of the world shown in Table -2. Reported uranium values are > 30µgL-1 in various U.S. community water samples. Average concentrations in groundwater were found to be 3 µgL-1 (Cothern et al., 1983) with ranges of 0.015-973.0 µgL-1 in domestic supplies in U.S. Uranium concentrations in domestic and surface water samples in India were 0.67-20.26 µgL-1( Bansal,1992) whereas in hot springs water it varied in the range 1.4-7.4 µgL-1 (Chakavarti et al., 1980). Uranium concentrations up to 700 µgL-1 have been found in private groundwater supplies in Canada (Moss et al., 1985). The mean uranium concentrations in over 1,00,000 surface waters throughout the UK has been determined to be 0.65 µgL-1 with a maximum observed concentration on of 233 µgL-1. In a 1980-1981 survey of 13 selected sites in south-central British Columbia the mean uranium concentration (n=519) in surface water and ground supplies was 4.06 µgL-1 (PBC, 1981). The mean and median levels of naturally derived uranium in ground water of 287 wells samples in southeastern Manitoba (1982-1984) were 58.3 µgL-1 and 10 µgL-1 respectively. Uranium concentrations in water from the western Himalayas to range from 0.89 to 63.4 µgL-1 (Virk, 2001). Concentrations of uranium in mineral waters from a high background region in Brazil to be 0.8 to 2.0 µgL-1. In a survey of 56 randomly selected bottled mineral waters in Europe observed uranium concentrations to range from 0.0104 to 9.49 µgL-1. Uranium is present in sea water at concentrations of about 3.3 µgL-1 (Keya, 1993). In estuaries concentrations are generally positively correlated with salinity and in open oceans range from 3.0 to 3.6 µgL-1. Experimentation has shown it may be a number of techniques such as ion exchange, ultrafiltration and reverse osmosis.

Maximum Acceptable Concentration (MAC) levels of uranium in drinking water of Australia is 15 µgL-1(ADWG, 1996), U.S. 30 µgL-1(USEPA, 2000), Canada 20 µgL-1 (WHO, 2003). In 1996, British Geological Survey (BGS) investigated groundwater of Bangladesh and the final report which published on June, 2000 (BGS, 2000) comprises mainly arsenic contamination in groundwater. Three special study areas established in the sadar (headquarter)) Thanas of


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Nawabgonj, Faridpur and Lakshmipur district for detail chemical parameters. They were basically looking for arsenic contamination in the natural drinking water. But they reported high arsenic concentration as well as high uranium concentration in some of areas. From their report the maximum uranium concentration observed was 47 µgL-1 from Nawabgonj district one of the worst arsenic affected areas of Bangladesh.

According to the United Nations Scientific Committee on the Effects of Atomic Radiation the normal concentration of uranium in soil is 300 µg/kg (micro gram per kg) to 11.7 mg/kg (milli gram per kg) ( UNSC 1993). Several studies (Paivi Kurttio et al,. 2005; Paivi Kurttio et al., 2006; Anssi Auvinen et. al., 2002 ; Odette Prat et al., 2009) focusing on health effects have been carried out in Finland among people who use their drilled wells as sources of drinking water. These include case-cohort studies of uranium intake and risks of leukemia, stomach, and urinary tract cancers as well as chemical toxicity studies of uranium intake and renal and bone effects. Nevertheless, none of the human studies reported so far have shown a clear association between chronic uranium exposure and cancer risk, clinical symptoms, or toxicity.

In present work it was found the range of uranium content to be 4.78±0.52 to 44.18±2.7 µgL-1 from different districts of northern part of Bangladesh. The uranium concentration in Nawabgonj ( 44.18 ± 2.7 µgL-1) and Rangpur (31.18±3.00 µgL-1) districts are exceed the range of MAC levels (30 µgL-1) of drinking water for health assesment. On the other hand the soil of these region is affected by uranium contamination. This is very harmful for crop production. It is necessary to measure uranium level through a comprehensive survey in drinking water like the survey was done for arsenic contamination. However, it is in well agreement with the data of British Geological surver (BGS, 2000). Table 2 shows that range of uranium concentration in groundwater world wide with the present work.

Table 1 Concentration of Uranium in drinking water of Northern part in Bangladesh with blank

test data for groundwater sample.

Detector number

Track density (Tracks per

cm2) Districts

Uranium concentration (µgL-1) using the straight

line equation of calibration curve.

Average Uranium content (µgL-1)

Sirajgonj 17.48 ± 1.11 Bogra 8.88±3.09

BLD1

796±28

Pabna 17.39±1.07 Joypurhat 13.87±2.03 Naogaon 4.78±0.52

BLD2

796±28

Rajshahi 20.59±2.00 Nawabgonj 44.18±2.71

Rangpur 31.18±3.00 BLD3

796±28 Dinajpur 14.99±3.12

19.17±2.07


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Map 1 Map of Northern part in Bangladesh in context showing location of sampling areas.

Table 2 Uranium concentration of groundwater in world wide.

SI. No. Location

Uranium concentration (µgL-1) References

1 Ontario, Canada 0.04- 4.21 (OMEE,1996) 2 USA 0101-652 (Nozaki,1970) 3 New York, USA 0.03-0.08 (Fisenne,1996) 4 Argentina 0.04-11.0 (Bomben,1996) 5 Australia >20 (Akram,2004) 6 Turkey 0.24-17.65 (Akram,2004 7 India 0.08-471.27 (Talucdar,1983) 8 Japan 0.0009 (Nozaki,1970) 9 Norway >20 (Frengstad.2000)

10 New Mexico >20 (Brown,1983) 11 Jordan 0.04-1.400 (Gedeon,1994) 12 Kuwait 0.02-2.48 (Bou-Rabee,1995) 13 South Greenland 0.5-1.0 (Brown,1983) 14 Himalayas 0.89-63.4 (Virk,2001) 15 Finland 2.1-290 (Kahlos,1980) 16 Cyprus 0.005-38 (Smith,20000 17 Pakistan 0.05-5 (Akram,2004) 18 Sea water 3.0-3.6 (Keya,1993) 19 Nawabgonj district (Bangladesh)


8

21 Bogra district (Bangladesh ) 8.88±3.09 22 Pabna district (Bangladesh ) 17.39±1.07 23 Joypurhat district (Bangladesh ) 13.87±2.03 24 Naogaon district (Bangladesh ) 4.78±0.52 25 Rajshahi district (Bangladesh ) 20.59±2.00 26 Nawabgonj district (Bangladesh) 4.18±2.71 27 Rangpur district (Bangladesh ) 31.18±3.00 28 Dinajpur district (Bangladesh ) 4.99±3.12

Author

Y=0.0007x+0.4348, R2=0.9978

020406080

100120140160

0 50000 100000 150000 200000 250000

Track Density (Tracks per square cm)

Ura

nium

con

cent

ratio

n (p

pm)

Figure 1 Calibration Curve for Uranium concentration (ppm).

05

101520253035404550

1

Districts

Uran

ium

Con

cent

ratio

n SirajgongBograPabnaJoypurhatNaogaonRajshahiNawabgongRangpurDinajpur

Figure 2 Concentration of Uranium in water of different districts of northern part of Bangladesh

with MAC level.

MCA level

(µgL

-1)


9

4. Conclusion Food and drinking water are the primary sources of uranium intake for the general public. Root crops such as potatoes, parsnips, turnips, and sweet potatoes contribute the highest amounts of uranium to the diet. The concentrations in these foods are directly related to the concentrations of uranium in the soil where the foods are grown. Hydroponically cultivated plants are grown on medium containing uranium. In our survey report provided that the tolerance level of uranium in groundwater of northern part of Bangladesh. 5. Acknowledgements The author’s express their heartfelt thanks to Chemistry Division of Atomic Energy Center, Dhaka, Bangladesh Atomic Energy Commission (BAEC). 6. References Akram, M. 2004. Fission Tack Estimation of Uranium Concentration in Drinking Water from

Azad Kashmir, Pakistan, Health Physics, 86(3): 296-302.

Auvinen ,A., Kurttio ,Paivi; Pekkanen , J.; Pukkala ,E.; Ilus ,T. and Salonen ,L.; 2002, Cancer Causes and Control, 13: 825-829.

Bansal, V., Tyagi, R.K. and Prasad, R. 1992. Determination of uranium concentration in drinking water samples by fission track method. L. Radiation Ucl Chem., 125: 439p.

BGS/DPHE (British Geological Survey/Government of Bangladesh Department of Public Health Engineering) 2001. Groundwater Studies of Arsenic Contamination in Bangladesh. Keyworth, UK:British Geological Survey. Available: http://www.bgs.ac.uk/arsenic/ bangladesh/home.html [accessed 6 December 2001].

Bleise. A., Danesi P.R. and Burkar W. T., BGS (British Geological Survey) 2000.Ground water studies of arsenic contentment of Bangladesh Final report. J. Environ. Radioactivity. 64: 93-112

Bomben, A.M. 1996. Ra-226 and natural uranium in Argentina bottle mineral water. Radiation Protection Dosimetry, 67: 221-224.

Bou-Rabee, F. 1995. Estimating the concentration of uranium in some environmental samples in Kuwait after the 1991 Gulf War, Applied Radiation Isotopes., 46: 217p.

Brown, A. 1983. Uranium districts defined by reconnaissance geochemistry in South Greenland. J. Geochem Explor. 19: 127-145

Cember, H. 1989. Introduction to Health Physics, Pergamon Press.

Chakarvarti, S.K., Lan, N. and Nagpaul, K. 1980. Uranium traces analysis of some material using solid state nuclear track detectors. In: The Solid state nuclear track detectors. Oxford: Pergamon Press; 701-715.

Cothern, C.R. and Lappenbusch, W.L. 1983 Occurrence of uranium in drinking water in the US, Health Physics, 45: 89-99

Environment Canada/Health Canada. 2003. Priority Substances List Assessment Report: Releases of Radionuclides from Nuclear Facilities (Impact on Non-human Biota). Prepared by Environment Canada and Health Canada, Ottawa, Ontario. ISBN 0-662-35410-9, Cat. No. En40-215/67E


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EST (Environmental Science and Technology) 1987. 21: 749p

Frisbie, S.H., Ortega, R., Maynard ,D.M. and Sarkar, B. 2002. The concentrations of arsenic and other toxic elements in Bangladesh’s drinking water. Environ Health Perspect 110:1147–1153.

Fisenne, I.M. 1993. Natural uranium content in soft tissues and bone of New York city residents. Health Physics. 50: 739-746.

Gedeon, R. 1994. IASH Publication, 232p.

Hartley, N.H. 1983. Radon and lung cancer in mines and homes. N.Eng. J. Med. 310: 1525-1527.

Health Canada, 2002. Summary of guidelines for Canada drinking water quality Ottawa.

Kahlos, H. 1980. International radiation doses from radioactivity of drinking water in Finland.” Health Physics. 39: 108-111.

Karpas Z., Paz-Tal O., Lober A., Salonen L., Komulainen H., Auvinen A., Saha H. and . Kurttio .P, 2005. Health Physics, 88: 229-242.

Keya, G.M.C. 1993. Tables of physical and chemical constants Longman group ltd, 15th edition.

Kurttio, P., Harmoinen , A., Saha , H., Salonen ,L., Zeev Karpas, P. Komulainen , H. and Auvinen, A. 2006. American Journal of Kidney Diseases, 47: 972- 982.

Kurttio, P., Komulainen, H., Leino, A., Salonen, L., Auvinen, A. and Saha, H. 2005. Environ Health Perspect. 113: 68-72.

Moss, M.A. 1985. Chronic low level uranium exposure via drinking water-clinical investigations in Nova Scotia, Nova Scotia: Daihousie University; Thesis.

Nero, A.V. and Lowder, W.M. 1984. Special issue on indoor radon. Health physics, 45: 273-570.

Nozaki, T. 1970. Radiation Chem., 6: 33-40

OMEE (Ontario Ministry of Environment and energy), 1996. Monitoring for uranium, 19990-1995, Toronto, Drinking Water Survellance Program.

PBC (Province of British Columbia), 1981. Variation in uranium and radioactivity levels in surface and groundwater at selecte4d sites in British Columbia April 1980-march 1981, B.C.

Prat ,O., Vercouter, T., Ansoborlo, E., Fichet, P., Perret, P., Kurttio, P. and Salonen, L.2009. Environ. Sci. Technol. 43: 3941-3946.

Robert, M.B. 1985. Statistical methods for engineers and scientists” Edition; Second edition, Revised and expanded, Vol 57, Marcel Dekker Inc, New York and Basel.

Singh, P., Singh Rana, N.P. and Naqvi, A.H. 1993. Quantitative determination of uranium in water samples from Allahabad ln: Srivastava DS Presad R, eds. proc. VIII Symposium. Achal Tal, Aligrah, India: Litho Offset Press: pp 197-201.

Smith, B. 2000. Proceeding of the 3rd international conferences on the Geology of the Eastern Mediterranean, Nicosia. Cyprus, Geneva, WHO/SDE/PHE/01, 1.


11

UNSC (United Nations Scientific Committee on the Effects of Atomic Radiation (1993). Sources and effects of ionizing radiation. United Nations. ISBN 92-1-142200-0] http://www.unscear.org/unscear/en/publications/1993.html

US EPA (Environmental Protection Agency), 1990. Occurrence and exposure assessment for uranium in public drinking water supplies, Report prepared by wade Miller Associates, Inc. for the Office of Drinking Water, US Environmental Protection Agency.

US EPA (Environmental Protection Agency), 1991. Review of RSC analysis, Report prepared by Wade Miller Associates, Inc. for the US Environmental Protection Agency.

US EPA (Environmental Protection Agency), 1992. Consumers guide to radon reduction. How to reduce radon levels in your home” EPA 402-K92-003, p17.

US EPA (Environmental Protection Agency), 2000. National Primary drinking water regulations: radionuclide final rules. Federal Register, 65: 7708-76753.

UNSC United Nations Scientific Committee on the Effects of Atomic Radiation (1993). Sources and effects of ionizing radiation. United Nations. ISBN 92-1-142200-0] http://www.unscear.org/unscear/en/publications/1993.html

Virk, H.S. 2001. Radiation Measurement, 34(1-6): 427-431.

WHO (World health Oganization), 2003. Guideline for drinking water quality, Health criteria and other supporting information, Geneva WHO.

EVALUATION OF GROUNDWATER SALINITY AND ARSENIC CONTAMINATION AND ITS ENVIRONMENTAL IMPACT IN SHYAMNAGAR

THANA OF SATKHIRA DISTRICT, BANGLADESH

S.M. Shafiuzzaman Institute of Environmental Science (IES), University of Rajshahi

Rajshahi-6205. Bangladesh. Email: [email protected]

Abstract Groundwater quality is rapidly decreasing in alarming rate due to surface water pollution by tremendous pressure of human activities. Groundwater in the study area is generally high salinity contaminated and peoples are facing drinkable safe water crisis. There are 12 groundwater samples have been collected from the different well locations of Shaymnagar Thana for hydrochemical analysis. The result shows that salinity and arsenic level are objectionable in most of the samples. Salinity is high which ranges from 0.4 ‰ to 3.5 ‰ with an average of 2.35 ‰. The average EC is 5912.25µS/cm exceed the WHO permissible limit, 2006 and DoE, 1997). High TDS, Na+, Cl- indicate high salinity in groundwater of the study area. Concentration of arsenic ranges from 0.009 to 0.078 mg/l, with an average of 0.052 mg/l which exceeds only the DoE permissible limit, but well above the WHO’s limit. To know the behavior of salinity and arsenic, few parameters especially pH, Ca2+, Mg2+, K+, HCO32+, NO3+, SO42+ and Fe value have also been used, most of which were within the limits of WHO’s standard except HCO32+. High salinity adversely affects the flora, fauna including human and infrastructures in the study area. Groundwater quality is unsuitable for drinking and agricultural purposes in most of the area and could be allowed alternative water resources.

Key words: Groundwater, Salinity, Arsenic, Environmental Impact, Bangladesh. 1. Introduction The study area is a coastal area of Satkhira district of Bangladesh, where groundwater is generally saline and also added arsenic contamination in recent year. According to the DPHE & BGS (2001) and National Hydro chemical survey indicate that the Satkhira district is worst-arsenic affected area, where 67% of sampled wells with greater than 0.05 gm/L in arsenic concentration. In this context, Shyamnagar Thana belongs to groundwater of arsenic risky area. Arsenic is alarming rate in groundwater which was also found its adjoining areas in West Bengal of India, specially 24-parganas exceeding 0.1 mg As/L ( the highest value recorded being 5.0 mg As/L) have been reported, ranging in depth from 13 to76 m ( Chaterjee et al., 1989; Ghosh, 1991). Concentration of As in groundwater ranges from 0.009 mg/l to 0.078 mg/l. with an average of 0.1117 mg/l, which were found in variable depth (27 to 240 feet). Groundwater extracted from shallow aquifer (9 to 36 m) is usually highly contaminated with As (Polizzotto et al., 2008). High As in drinking water may create health hazard in the area. Skin cancer, caused by drinking water containing 0.5 mg/l As has been observed in China (Handa, 1977). Salinity is also an important problem in the study area which may be measured by the electric conductivity (EC). According to GoB report, in Satkhira area salinity is normally high, the variation is lowers during the January/February, when EC is 5,000 to7,000 micro mhos/cm and this may up to 30,000 micro mhos/cm in April and May. The study result shows Electric conductivity (EC) ranges from 838–11808 µS/cm. Salinity contamination is normally high in maximum area, exceeds WHO (2006) permissible limit (400 to 1500 µS/cm). High EC content of water is harmful for drinking and Irrigation purposes. Conductivity and Na+ play a vital role in suitability of water for irrigation


Evaluation of Groundwater Salinity and Arsenic Contamination Shafiuzzaman

13

(Rao, 2005). Groundwater salinity result is undesirable for using purposes which ranges from 0.4 to 3.5 ‰. To know the behavior of arsenic and salinity, other metal ions and anions- Na+, Ca2+, Mg2+, K+, Cl-, HCO32+, NO3+, SO42+ and Fe has also measured by using the analytical methods. Few physical parameters such as pH, TDS values have been measured to characterize the water quality .In the study, arsenic and salinity effect on the local environment have been assessed based on the field observation. 2. Materials and Methods 2.1 STUDY AREA The study area is a part of Bengal basin and lies in the southwestern portion of Satkhira district of Bangladesh and is located between latitude 22°10´ and 22°26´ N and longitude 89°00´ and 89°18´E. The area is a coastal adjoining area covering an area of about1968.28 sq.km. and is bounded by Kaligonj and Assasuni Thana on the north, Sundarbans and Bay of Bengal on the south, Koyra and Assasuni Thana on the east and west Bengal of India on the west shown in figure 1. The area is economically important and rich in biodiversity, because part of the world largest mangrove forest Sundarbon is in this area. Moreover, numerous activities such as fish cultivation in saline water Ghair (Local name), Agriculture and industry especially fish production and fish processing industry etc go on in the region.

Figure1 Location map of the study area


14

2.2 SAMPLE COLLECTION AND PROCEDURE Groundwater samples were collected from 12 well locations in the Shyamnagar Thana during May 2011. These wells are used either for domestic and/or agricultural purposes. The wells were chosen to represent all the area on the basis of their suitable geographical location (Figure1) and different well depth (figure 2). Samples were collected manually and stored in 500 ml clean plastic bottles with air tight screw cork. Two bottles of groundwater samples of each station have been collected. One bottle of water sample for arsenic analysis in which HNO3 (.01 N) was used for maintains pH within the limit of 2 to 3 to control the changing characteristics of water and another bottle of water sample was freshly collected from tube well without any type of acid to detect other chemical parameters specially major cations and anions and few trace element. After collection of water samples that were brought to the research Laboratory immediately for hydrochemical analysis. Environmental impact in the area has assessed from the collection of direct field observation data and interview information from local peoples. In table1 shows the details field observation data.

Figure 2 Groundwater sampling at different depth in the study area

2.3 METHODS OF ANALYSIS Keeping consistency with objectives in the present research of arsenic and salinity determination are a normal phenomena. But the determination of other physical and chemical parameters of groundwater samples is also important to know the behavior of arsenic and salinity with them. The study is conducted to apply field observation data and chemical analysis data from laboratory. Salinity is usually reported as electrical conductance (EC) which is measured in each station of the field by using potable electro conductivity (EC) meter (HANNA HI 7039 P). Salinity was also measured in parts per thousands(‰) by using Eco Scan instrument from the Isotope Hydrology division, Atomic Energy Research Establishment, Savar Dhaka. TDS is another important parameter to measure salinity of water which is measured as a calculated value by using the Aqua Chem. (Version 3.70) software in the study. Arsenic concentration in groundwater have been measured with Atomic Absorption Spectrophotometer (Model: ZEEnit 700, Analytik Jena, Germany) by using standard methods form the Isotope Hydrology division, Atomic Energy Research Establishment, Savar Dhaka. Ca2+, Mg2+ and Fe also measured to apply

Dep

th in

feet


15

same methods and instruments, but Na+, K+ is measured by Flame Photometer (Model: PFP 7, ZENWAY, UK). The major anions (Cl-, NO3-, SO42- , HCO3-) is measured with Ion Chromatography (Model: ICS -3000, DIONEX, USA) from the same laboratory. The pH is measured in each station by using potable HANNA Pocket pH meter during the water sample collection. 3. Results and Discussions 3.1 FIELD OBSERVATION RESULT The result obtained from direct field survey in the area during water sample collection to get the primary idea of groundwater quality mainly salinity scenario. The observation indicates that maximum tube well in the area is highly saline and some tube wells contain medium saline and a few number of tube wells contain saline free water shown in table1. The study area is located in coastal area and a vast network of rivers are connected with the Bay of Bengal and maximum river contain saline water. So observation also decided that the high groundwater salinity in this area mainly may occur due to sea water intrusion, saline water logging that reason excessive saline water uses in Ghair (local name) for fish cultivation, and excessive withdrawal of fresh ground water in that area. Another process like, dissolving the soluble components of the weathered aquifer material; the use of fertilizers, insecticides and pesticides contribute to increase the salinity of the groundwater marginally. But the area is low agriculture area where paddy, wheat, potato sugarcane etc. cultivations are very rare. Recently such type of cultivation is occurring in some area in small scale by using harvested rain water. So this is not responsible for increasing salinity in the area. Arsenic test was done in the field by Arsenic field kits and number of NGOs identified some tube wells which are arsenic contamination by marking red colour in the area. Although there are any arsenic patient did not identified in the study area during field observation shown in table1. Similar results were also point out in the area surveyed by Bangladesh arsenic mitigation water supply project (BAMWSP, 2003).

Table1 Field data of groundwater in the area

Sample ID & location Sources Depth (ft) Taste result As Patient

S1 (Shyamnagar) STw 185 Normal No S2 (Shyamnagar) STw 30 Light salty No S3 (Nurnagar) STw 100 Medium salty No S4 (Kaikhali) STw 30 Very light salty No S5 (Iswaripur) DTw 240 Medium salty No S6 (Iswaripur) STw 27 Light salty No S7 (Munshigonj) DTw 215 Very light salty No S8 (Atlia) DTw 230 Salty No S9 (Kashimari) DTw 230 Medium salty No S10 (Kashimari) STw 175 Salty No S11 (Bhurulia) STw 55 Normal No S12 (Bhurulia) DTw 240 Medium salty No

*STw= Shallow tube well (>200 ft); DTw = Deep tube well (


16

Table 2 Concentration of various constituents in Groundwater of the well locations in study area Sample

ID pH EC

(µS/cm) Salinity

(‰) TDS

(mg/l) As

(mg/l)Na+

(mg/l) Ca2+

(mg/l)Mg2+ (mg/l)

K+ (mg/l)

Cl- (mg/l)

HCO3- (mg/l)

NO3-

(mg/l) SO42-

(mg/l)Fe

(mg/l)

S1 7.3 838 0.4 459 0.052 92.71 48.31 30.47 10.31 138.44 368 0.07 2.16 0.25 S2 8.2 3917 1.8 3030.5 0.071 967.53 56.14 52.07 18.31 1704.86 857 0.12 46.37 1.27

S3 7.0 7460 3.2 4280.1 0.063 1642.18 32.38 58.92 20.41 2306.98 865 0.15 62.38 1.20

S4 7.3 6820 3.1 4264.2 0.022 1592.7 60.14 53.15 18.91 2290.45 860 0.10 69.35 1.24 S5 7.4 6693 2.9 4187.5 0.056 1593.25 67.26 54.89 12.86 2197.13 864 0.05 66.41 0.73 S6 7.7 3875 1.6 2920.8 0.074 883.47 57.06 51.47 19.63 1679.04 852 0.14 42.35 1.35 S7 7.0 3280 2.9 2529 0.012 848.41 51.89 46.27 12.48 1363.60 608 0.09 33.26 1.26 S8 7.0 1178 2.2 5011.5 0.009 1735.92 68.48 59.39 14.76 2845.83 928 0.05 98.26 0.82

S9 7.7 6728 2.7 4186.3 0.062 1563.47 65.74 58.51 15.06 2214.34 917 0.06 67.58 0.64 S10 7.5 11808 3.5 4904.8 0.071 1563.47 65.74 58.51 15.06 2214.34 917 0.06 67.58 0.64

S11 7.7 876 0.6 608.3 0.078 94.08 53.75 51.75 16.57 179.85 441 0.10 5.87 1.47

S12 7.5 6872 3.3 4320.1 0.053 1614.54 69.58 57.36 13.17 2292.30 763 0.04 70.31 0.79

Average 7.29 5912.25 2.35 3392.67 0.052 1199.70 56.20 50.56 15.32 1839.79 724.92 0.09 55.64 0.94 WHO (2006)

Standard

6.5 to 9.6

400 to 1500 NS

500 to 1500

0.01

10 to


17

the seawater intrusion and especially Cl- and TDS concentrations are the simplest indicators for the salinization process (Jin-Yong Lee, et al., 2007). The study result shows that the average TDS in the water is 3392.67 mg/l, the average Na+ concentration is 1199.70 mg/l and the average Cl- is 1839.79 mg/l. All of these are much above the WHO and DoE recommended permissible limit shown in table 2. High concentration of TDS, Na+ and Cl- indicate that groundwater in the area is high salinity content occurred due to sea water intrusion.

Table 3 Wilcox (1948) classification of water for agriculture purposes in the study area Water Class EC (µS/cm) No. of water samples

Excellent 3000 9

Figure 5 Variation of groundwater salinity with well depth in the study area

Figure 3 EC level in Groundwater in different well locations of the study area

Figure 4 Groundwater salinity in different well locations of the study area


18

3.2.2 ARSENIC (As) The concentration of As in groundwater in the study area ranges from 0.009 to 0.078 mg/l, with an average of 0.052 mg/l, which is just above the DoE recommended limit (0.05 mg/l), but high for WHO permissible limit (0.01 mg/l). The highest As value was found in the well location of Bhurulia (S-11) at 55 feet depth and the lowest values was found in the well location of Atlia (S-8) at the depth of 230 feet shown in table2 and graphically represented in figure 6 and in figure7. Figure 6 shows the arsenic concentration level in groundwater of different well locations in the study area. Figure7 shows that in most of the groundwater samples, arsenic concentration is above 0.05 mg/l which are below the depth of 250 ft, and comparatively high arsenic concentration was found approximately in more shallow depth in the study area. Other chemical parameters, Ca2+ and Mg2+ range from 32.38 to 69.58 mg/l and 30.47 to 59.39 mg/l respectively which are below the WHO and DoE recommended limit. So in respect of Ca2+ and Mg2+, groundwater is suitable for domestic purposes. K+ concentration ranges from 10.31 to 20.41 mg/l with an average of 15.32 mg/l, which is slightly above the WHO limit, but below the DoE limit. The concentration of average NO3- and SO42+ are 0.09 mg/l and 55.64 mg/l which are below the both permissible limit, but HCO32+ is high and the average concentration is 724.92 mg/l. The average Fe concentration in groundwater is 0.94 which is below the WHO recommended limit. pH of the ground water samples in all unions of the studied area found in vary from 7.0 to 8.2, which indicate water are practically neutral to alkaline in nature. 3.3 ENVIRONMENTAL IMPACT Peoples are facing serious problem due to scarcity of drinkable fresh water in study area. The average arsenic concentration in groundwater just exceeds the permissible limit, and its impact does not affect severely in the area. There are no available arsenic patients in this area. On the other hand, high salinity is harmful for living things especially for plants. Very high salinity is harmful for plants growth, physically by reducing the uptake of water through modification of osmotic process or chemically by metabolic reactions caused by the toxic constituents; besides this, the salinity of this magnitude, changes the soil structure, permeability and aeration which in turn effect the plants growth and yield of crops considerably (R.P. Singh et al, 1994). Field survey shows that the salinity adversely affects the flora, fauna including human and infrastructures in the study area of which details are stating below and photographs are shown in figure-8.

Figure 6 As concentration level in Groundwater of different well locations of the study area

Figure 7 Variation of As concentration in groundwater with depth in the study area


19

3.3.1 EFFECT ON FAUNA Expansion of salinity in water is leading to destruction of animal life in the area. It causes a lot of changes different kinds of vertebrates and invertebrates. Among the vertebrates, fox, mongoose, squirrel, snake, dog, cat etc. are affected and consequently such animals, especially Fox and Mongoose are on the way of extinction. Moreover, the effect of salinity losing grassland and its adverse impact on the number of cattle, cows, and buffalos, goats, sheep etc. and such animals are also decreasing hugely in this area. A large number of peoples are involved in shrimp cultivation. As a result, saline water fishes are increasing and alternatively fresh water fishes like-Chital, Roui, Koi, Shole (Bengali name) etc. are decreasing consequently. In future, such fishes will become extinction in this area. Other different kinds of invertebrates, like microbes, insects, mullasca etc are also being extinct due to the adverse effect of salinity. The role of these animals in keeping the balance of environment is undeniable.

3.3.2 EFFECT ON FLORA Plant is very important for all living things and its sensitivity is very high than any other living things. There are many kinds of woody and fruit trees such as mango, papaya, banana, guava, berry-berry, jackfruit, palm, date and coconut etc decreases rapidly due to high magnitude of salinity in this area. In addition, paddy, wheat, green vegetables and even straws and hays etc production has also alarmingly declined.

3.3.3 EFFECT ON HUMAN The declining agricultural production, loss of fruit trees, open fishery has adversely affected the economic condition of some people in this area. A major part of population in the area is poor and mostly they are suffering for fresh water crisis and facing different types of health hazards due to saline water uses. Human health is especially influenced by the sole dependence on saline water for domestic purposes (BWDB et al., 1998). Sick health and vitamin deficiency patients are common in maximum poor family. As a result, large numbers of peoples in this area are obviously dependent upon the ponds and canals water. They are using this surface water for drinking and domestic purposes without purification. Just they are only using cloth for purify water. As a result, major percentages of people are suffering various types of diseases- diarrhoea, dysentery, typhoid, jaundice etc in some places of the study area.

3.3.4 EFFECT ON AGRICULTURE Due to the scarce of Irrigation water, agriculture practice especially crop production- paddy, wheat etc are decreasing dramatically.Few crops production is occurring in some area where farmers are using irrigation water from harvested rain water. Alternatively peoples are encouraging salinity tolerance fish cultivation.

3.3.5 EFFECT ON SUNDARBAN The study area is highly significant due to the part of Sundarbans involvement. Some peoples are living here depending upon the sundarbans. The declination of agriculture they are encouraging the collection of sundarban’s forest like- sundari, garan, kaora, golpata, honey, and also hunting various types of animals’ like-elephant, dear, birds, etc. The salinity effect on sundarban, decrease the flora and fauna dramatically. According to forest department, 40% of the total sundari trees have already fallen prey to the top dying syndrome due to increase salinity. This is also threatening the survival of the few Royal Bengal tigers. 3.3.6 EFFECT ON SOCIAL INFRASTRUCTURE There are number of houses, roads, government and non government offices, school and college buildings, polls of telephone and electrics and other concrete structure are damaging due to the influence of salinity in this area.


20

Figure 8 Salinity impacts on the environment in the study area (Photographs was collected

by the author during the field work in 2011)

Effect of salinity on the tube-well Salinity effects on animal and plant life

Drinking water scarcity effect on human health.

Salinity effect on the plants near gher

Salinity effect on infrastructure Salinity effects on the crop production


21

4. Conclusions and Recommendations In this study groundwater quality especially salinity and arsenic contamination was evaluated using groundwater chemistry data. The chemical result denoted that groundwater is highly saline content and unusable for drinking and agricultural purposes. Salinity is closely related to the Na+, Cl-, EC, and TDS. High concentrations of these parameters are the simplest indicators for the salinization process and high salinity groundwater. Arsenic in groundwater varies from place to place between 0.009 mg/l and 0.078 mg/l with an average of 0.052 mg/l which is just above the Bangladesh standard limit (DoE, 1997), but its impact does not found remarkably in the area. It may be the additional burden in future for the living peoples. Due to high salinity there are number of flora such as, papaya, banana, guava, berry-berry, jackfruit, palm etc and fauna such as fox, mongoose, squirrel, snake, buffalos, goats, sheep and koi, shole fiches are on the way of extinction. Crop production is also decreasing rapidly in the study area. Water born diseases- diarrhoea, dysentery, typhoid, jaundice patients were found significantly. So keeping in view the greater welfare of the people in the area should be taken proper steps in nationally to keep free from the harmful effect of arsenic and salinity effects. Locally instant peoples have to avoid such contaminated groundwater from the identified wells. Instead of it, harvesting rainwater, pond water with proper treatment may be used for drinking purposes in temporarily. For long term, responsible department have to be proper planning to find out the saline and arsenic free aquifer. In addition, proper management and maintenance of surface water may helpful to reduce the drinking water crisis. 5. Acknowledgements The author wishes to thanks to the director and all teaching staffs of the IES, Rajshahi University, Bangladesh, for giving the necessary facilities to carry out this work. Many thanks to Md. Moniruzzaman, Scientific officer, Isotope Hydrology division, AERE, Savar, Dhaka, for providing the laboratory facilities. 6. References

BAMWSP 2003. Bangladesh arsenic mitigation water supply project report. http:www.bamwsp.org.

BGS, DPHE 2001. Arsenic contamination of groundwater in Bangladesh”, vol. 2, final report, BGS tech. report WC/00/19.

BWDB, DHV International, DDC and SWMC 1998. Draft Master Plan. Volume 2: Morphological Processes.

Chaterjee, T. K. 1989. Arsenic contamination of portable waters of West Bengal. J. Inst. of Chemists (India). 61: 197-198.

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ANALYSES OF THE PRE AND POST FARAKKA RAINFALL AND WATER DISCHARGE PATTERN OF THE RIVER GANGES (BANGLADESH PORTION)

AND ITS IMPACT ON ENVIRONMENT

M. N. U. Shaikh1,2 , M.G. Mostafa2, M. A. H. Sheikh1, M. Z. Hassan1 1 Geography and Environmental Studies, Rajshahi University, Rajshahi, Bangladesh.

2 Institute of Environmental Science, Rajshahi University, Rajshahi, Bangladesh. Abstract

An attempt was made to analyze the pre- and post -Farakka rainfall and water discharge data for 50 years from1962 to2011 of the river Ganges basin in the Bangladesh portion with the help of standard statistical methods. The post-Farakka trend of mean, minimum and maximum data was compared with the Pre- Farakka data. Almost 75% of total rainfall occurred during monsoon season and the seasonal variations were found throughout the study period. The maximum water discharge in the rainy season increased to +2.28% suddenly in August and September while the minimum water discharge in the dry season was recorded -65%, indicate a reduction in water discharge during dry season in post-Farakka period. The results illustrate that the water diversion from the river Ganges at Farakka made significant changes in the hydrological characteristics in the study area. Moreover, the results could be used for the prediction of water discharge pattern, making crop calendar, crop water budget, water management as well as various economic activities.

Key words: Bangladesh, discharge, environment, Farakka, Ganges, impact, rainfall, river-water 1. Introduction Bangladesh is a water scarce country especially in the dry season. At present, a large volume water needs for agriculture, industry, rural and urban sectors mainly driven by increases in population and economic growth (Mirza, 1998). Possible climate changes may affect the water resources of the river Ganges in Bangladesh portion indirectly (Ipcc, 2007). Changes in hydrology and water resources may result in changes in the pattern and magnitude of water discharge, water level and flood frequency as well as the river morphology (Hosterman et al, 2009). The river hydrology regime changes would have a direct effect on life styles, and hence on human behavior (Chowdhury, T. N. 2010). As a result, people suffer from shelter and food-clothings, become patients of waterborne diseases and brought overall environmental imbalanced condition, on the other hand, insufficient water, brings drought with a scene of no crops and ultimately hunger which will bring about the greatest polluter of the environment (Sheikh, 1995). Increasing population, economic growth and climate change related factors will eventually exacerbate stress on water use and widen the gap between demands and supply (Mirza and Ahmed, 2005; Chowdhury and Ward, 2004; Kothyari et al., 1997) of the water resources in basin area.

Bangladesh is a land of rivers and about 90% of its land is formed by them. More than 80% of the lands of Bangladesh is floodplain type which undoubtedly formed by the gradual depositional sediments (alluvial) borne by the rivers (Brammer, 1988). It is a country of about 150 million people; just under one in ten of humankind and most of them concentrated in the floodplain areas with agro-based economy (Begum, 1987; Mirza, 2005, BBS, 2010). Rivers not only provide waterways to transport the agricultural goods as well as other commodities from one place to another that also provides accommodation, drinking and washing water, irrigation, industrial water


Analyses of the Pre and Post Farakka Rainfall and Water Discharge Pattern Shaikh et al.

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supplied use and act as a reservoir for pisciculture (Nishat, 1995). During floods (monsoons), these rivers carry huge amount of alluvium along with water. Again, during the lean flows, there is a heavy deposition of silts in the beds of the rivers (Verghese, 1990). This has directly reduced the supply of water for its distributaries (Planner and Ralsanen, 2002). Thus, throughout the year, there are changes in rainfall, water discharge, landforms, and banks of the river taking place as well as the socio politico economic and natural ecosystem of the region as a whole (Islam et al., 2008).

The river Ganges is an international river shared by China, Nepal, India and Bangladesh. The river basin area consists of 10,87,300 sq km, which occupies about 79%, 14%, 4% and 3% by India, Nepal, Bangladesh (this is equivalent to 37% of Bangladesh) and China, respectively (Mirza, 2005). Thus, the river has great importance for the socio-economic development of the co-basin countries. It is estimated that about 500 million people are directly or indirectly dependent on the river Ganges (IPCC, 2007). For the river Ganges basin in Bangladesh, a regular water supply from upstream is needed, particularly during the dry season (November-May), for agriculture, domestic and industrial purposes; for maintaining river depths, sustaining fisheries and forestry; and for keeping in check inland penetration of sea water from the Bay of Bengal (Rashid, 1991). Until 1975, the river was unregulated and the supply of water in the dry seasons was adequate. In that year, a barrage on the river Ganges at Farakka (18 km upstream from the Bangladesh border) was commissioned by India (GOB, 1996). The purpose of the construction was to divert 1133 cumec of water from the river Ganges to the Bhagirathi-Hooghly river in the name of maintain the navigability of Calcutta Port (Abbas, 1984). Since the commissioning of the Farakka Barrage, the hydrology of the river Ganges system in Bangladesh was changed significantly. During the monsoon, discharge in the river Ganges was increased while in the dry season, it was decreased (Mirza, 1997). The inadequate supply of water in the river Ganges during the dry season was caused momentous socio-economic impacts through disrupting agriculture, fisheries, forestry, navigation and enhancing salinity intrusion further inland from the coast (MOEF, 1995). Much of the techno-political debate over the impact of the Farakka Barrage on Bangladesh is based on general observations and subjective evidence rather than sound analyses of relevant data. The main objectives of the study are to examine the rainfall and discharge pattern changes that were occurred in the river Ganges system in Bangladesh portion in the pre-post-Farakka periods and their statistical significance. The present paper focuses on the evaluation of rainfall and discharge pattern, and analyses the environmental impact of the study area and find out the mitigation measures. 2. Materials and methods 2.1 STUDY AREA Bangladesh is a small country but has a huge population which extends from 20°34′ to 26°33′ North Latitude and from 88°01′ to 92°41′ East Longitude(Rashid, 1991). The study area encompasses the whole of the present Rajshahi, Natore, Pabna, Nawabgonj and Kushtia district. It is bounded on the north by Naogaon district, on the east by Bogra and Sirajganj district, on the south by Meherpur, Chuadanga and Jhenaidah district and India and on the west by India. It lies between 23°43′ to 25°03′ North Latitudes and between 80°00′ to 89°58′ East Longitudes. Map of the river Ganges basin area and location map of the study area is shown in Figs. 1 and 2, respectively.


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Figure 1 Map of the river Ganges basin area.

Figure 2 Location map of the study area.

2.2 METHODS The methodology of the study is determined by the techniques of investigation, conceptual content of explanations and logical structure of explanation. The present study is principally based on data obtained from secondary sources, field observation and laboratory works. The relevant data of the rainfall and water discharge were collected from the Bangladesh Water Development Board, Dhaka (BWDB). The relationship between rainfall and discharge of the river Ganges at the Hardinge Bridge station was analyzed to find out environmental impact in the study area. By using Ms Excel and SPSS programs, 50 years (1962-2011), rainfall and water discharge data were analyzed for this purpose. Trend line, R values, R squared values, line graph, bar diagram, etc. were drawn to analysis the river Ganges rainfall, water discharge and their impacts on environment. 2.3 ENVIRONMENTAL IMPACT ASSESSMENT Environmental Impact Assessment (EIA) is a formal process to examine the environmental consequences of proposed development projects, program and policies, and suggests relevant management actions of the study area (LGED-1997). The EIA method proposed by LGED (1992) was used for the impacts assessment of the study area.


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3. Results and Discussion 3.1 PRE-FARAKKA PATTERN OF RAINFALL AND WATER DISCHARGE DURING 1962-1976 The study rainfall and the discharge pattern of the river Ganges at the Hardinge Bridge show the regression relationships between them. The annual maximum discharge and rainfall at Hardinge Bridge station from 1962 to 1976 were analyzed. The mean regression R2 and R values of the pre-Farakka were calculated to be 0.4566 and 0.6660, respectively (Table -1). These values indicate no significance relationship. The highest and lowest mean water discharges were 37996.43 and 1928.36 cumec, respectively. The mean values of the maximum, minimum and total annual rainfall of the pre-Farakka were 386.71, 0.36 and 1474.5 mm, respectively (Table -1). The diamond marks in Fig-3 clearly demonstrated changes in the slope during the pre-Farakka period. The figure illustrates that no significant relationship between the water discharge and rainfall data was made in the pre-Farakka period of the hydrological systems in the study area. 3.2 THE POST-FARAKKA PATTERN OF RAINFALL AND WATER DISCHARGE DURING 1976-2011 The regression relationships between the discharge and rainfall at Hardinge bridge station during the post-Farakka period (1976 to 2011) of the river Ganges basin is shown in Fig-3. The post-Farakka mean R2 value and R value were calculated to be 0.3963and 0.6066, respectively (Table- 1). The highest and lowest mean water discharge was recorded to be 41606 and 793 cumec, respectively. The maximum, minimum and total rainfall of the post-Farakka recorded were 427.1 mm, 0.40 mm and 1517.0 mm, respectively (Table- 1).The distinction percentage of the regression R2 and R values of the pre-post Farakka were reduced to -13.2105% and -8.9176%, respectively (Table -1). The diamond in the figure (Fig -3) clearly demonstrated changes in the slope during the post-Farakka period, the slope become steeper than that of the pre-Farakka period. This means that, for a given peak discharge at the Hardinge Bridge, the corresponding peak discharge for the post-Farakka is now lower compared to the Pre-Farakka period. It was cleared that the reduced discharge in the Ganges river was caused by manmade factors.

Figure 3 The pre and post Farakka regression relationships between annual average rainfall and

annual average water discharge of the river Ganges (1962-2011)

The pre-post Farakka distinction of the maximum, minimum and total rainfall increased to 10.43%, 7.05% and 2.88%, respectively (Table 1). Since the rainfall was not only the main factor of yearly variation of the river Ganges discharge but also a project and Farakka sluice gate operations decrease in rainfall in the upstream drainage basin in India and Nepal showed a significant reduction in river Ganges water discharge.


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Table 1 Differences between the pre and post-Farakka rain fall, water discharge and regressions

Period Highest

discharge (cumec)

Lowest discharge(cumec)

Maximum water

discharge (cumec)

Maximum rainfall (mm)

Minimum rainfall (mm)

Annual total

rainfall (mm)

R2 value

R value

Pre-Farakka 37996.43 1928.36 47592.31 386.71 0.36 1474.5 0.4566 0.6660Post-Farakka 41606 793.00 52343.62 427.10 0.40 1517.0 0.3963 0.6066Difference % 9.50 -58.88 11.50 10.43 7.05 2.88 -13.2105 -8.918

Source: Bangladesh water development board, surface water hydrology department-2, Dhaka, 2011

Therefore, decreases in mean discharge of the river Ganges should not be attributed to rainfall pattern. The pre-post Farakka difference percentage of the highest and lowest mean water discharge was observed 9.50% increased and -58.88% decreased, respectively (Table-1).The analysis results of the pre-Farakka water discharge of the river Ganges show that the major floods occurred during the month of August and September. On the other hand dry season appeared in the month of March and April (Table-2). The lowest discharge of the river Ganges was shown in March 1963 that was estimated to be 1190 cumec (Table-2). The mean and standard deviation of the minimum water discharge were 1841.58 and 325.58 cumec, respectively (Table-2). The maximum highest peak was observed in September 1962 that was found to be 73200cumec and their mean and standard deviation were 51141.67cumec and 8261.39cumec respectively (Table-2).The percentage of water coming from outside of Bangladesh was estimated from yearly mean water discharge and yearly mean rainfall and the results show that the percentage were 98.43 and 98.12 for the pre- and post-Farakka period, respectively, indicating that there was no significant change was observed between the two periods (Table 3).The distinction ratio between the highest and lowest discharge of the river Ganges were noticed very high that were found to be 42.80 and 19.80 and their mean and standard deviation were 28.60 and 7.05 (Table 2) respectfully. But the distinction ratio should be below 10 for keeping the hydro-morphological balance of the river (Davis, 1909). Table 2 Differences between the pre and post-Farakka maximum and minimum water discharge

Period Maximum

water discharge in cumec

Year and

Month

Minimum water discharge in

cumec

Year and month

Differentiation ratio between the highest and lowest

discharge Pre-Farakka the lowest 36800 1965, September 1190 1963, April 19.80

Pre-Farakka the highest 73200 1962, September 2360 1964, March 42.80

Pre-Farakka Mean 51141.67 1841.58 28.60 Pre-Farakka STD 8261.39 325.58 7.05

Post-Farakka the lowest 31600 1989, September 182.84 1997, March 41.79

Post-Farakka the highest 76000 1987, September 1210 1979, March 298.00

Post-Farakka Mean 52308.08 629.82 95.64 Post-Farakka STD 10824.31 241.63 49.09

Difference of Mean % +2.28% -65% 67.03% Difference of STD% +31.02% -25.78% 42.04%

Source: Bangladesh water development board, surface water hydrology department-2, Dhaka, 2011


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The analysis data of the 35 years post-Farakka water discharge of the river Ganges illustrate that the major’s flood was occurred during the month of August and September (Table-2). On the other hand dry season was seen in the month of March and April. The lowest discharge of the river Ganges was shown in March, 1997 that was estimated to be 182.84 cumec among the 35 years minimum discharge (Table-2). The mean and standard deviation of minimum water discharge were calculated to be 629.82 and 241.63 cumec, respectively (Table-2). The maximum highest peak was observed in September 1988 that was 76000 cumec and their mean and standard deviation were 52308.08 and 10824.31 cumec, respectively (Table-2). Possible changes in the mean discharge series were examined. Pre and post-Farakka Hardinge Bridge monthly highest mean water discharges were found to be 51141.67 and 52308.08 cumec, respectively, indicating that a +2.28% increase in maximum mean water discharge was occurred during post-Farakka period (Table-2). The standard deviations of the two periods were calculated as 8261.39 and 10824.31 cumec, respectively, indicated that a +31.02% increase in the standard deviation were occurred during the post-Farakka period (Table-2). The pre and post-Farakka monthly lowest mean water discharges were found to be 1841.58 and 629.82cumec, respectively, illustrating that a -65% decrease in lowest mean water discharge was occurred during the post-Farakka period (Table- 2). The standard deviations of the two periods were calculated as 1841.5 and 241.63 cumec, respectively (Table-2), indicated that a -25.78% decrease (Table-2) in the standard deviation was occurred during the post-Farakka period.

The mean differentiation ratio on 50 years between the highest discharge and the lowest discharge of the river Ganges was calculated 42.04 (Table-2). In post-Farakka days, from the dry season to rainy season, the maximum flow of water through the river Ganges used to be in the minimum range of 182.84-76000 cumec (Table-2). The difference ratio between the highest and lowest discharge of the river Ganges were noticed very high that was estimated to be 298.00 and 41.79 and their mean and the standard deviation were calculated 95.64 and 49.09 (Table -2) correspondingly.

Reduction in dry season discharge in the river Ganges in the study area was generated a series of hydro-morphological impact on environment. Due to continuous withdrawal of water through Farakka barrage for the last 35 years a significant number of rivers in the river Ganges basin of the study area have already turned into dead rivers. The river Ganges, a pre-Farakka mighty river now is almost going to be dead and some part of the river Ganges are using for agriculture land. For the analysis given Pre-Farakka and post-Farakka discharge and rainfall, suspended sediment discharge, the hydraulic geometry of the river Ganges channel width, depth and slope were obtained from the power function equation analysis that indicated the width was large and the depth w

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