Vol 4 - Environ. Sci-Eze

8/9/2019 Vol 4 - Environ. Sci-Eze

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Continental J. Environmental Sciences 4: 36- 43, 2010

Wilolud Journals, 2010

ECODYNAMICS OF EXCHANGEABLE CATIONS AND ANIONIC POLLUTANTS OF A NIGER DELTARIVER SEDIMENT RECEIVING INDUSTRIAL EFFLUENTS.

Eze, V.C. and G.C. Okpokwasili

Department of Microbiology, University of Port Harcourt, Port Harcourt, Nigeria

Abstract

The exchangeable cations and anionic pollutants of Okpoka-Woji River serving as a sink for

effluents of industries located in the vicinity within the Trans-Amadi industrial area were

carried out. Sediment samples were collected from six sampling stations located along the

channel for the assessment of exchangeable cations namely calcium, magnesium, potassium,

and sodium and nitrite, nitrate, ammonia, ammonium, sulphate, sulphite and phosphate. The

mean values for the exchangeable cations namely calcium, magnesium, potassium and sodium

ranged from 387.56 to 1775.78mg/kg; 2093.67 to 4517.38mg/kg; 134.27 to 1393.49mg/kg and

1140.87 to 8293mg/kg respectively. The mean values for nitrate, nitrite, ammonia and

ammonium varied from 49.44 to 98.97mg/kg, 45.94 to 73.44mg/kg, 13.55 to 27.30mg/kg and

14.33 to 28.87mg/kg respectively. Sulphate, sulphite and phosphate mean values ranged from

1492.17 to 9389.58mg/kg, 1243.47 to 7062.25mg/kg and 3.13 to 8.01mg/kg respectively. The

work showed that the river is polluted by theses parameters from the activities of industries

operating in the area.

KEYWORDS: Ecodynamics, exchangeable cations, anionic pollutants, sediments, industrial

effluents, Niger Delta River

INTRODUCTION

One of the most important characteristics of bottom sediments is their ability to exchange cations with the

surrounding aquatic medium. Cation exchange capacity measures the capacity of a solid, such as sediment to sorb

cations. It varies with pH and salt concentration. Furthermore, because of their capacity to sorb and release hydrogenions, sediments have an important pH buffering effects in some waters. Ion exchange has been seen as one of the

most important chemical phenomenon by which diagenetic changes occur after terrestrial sediments are deposited in

the marine environment. It has been observed that variations in the concentrations of potassium and magnesium

affect diagenetic changes (Parashiva et al, 1972; Manahan, 2001).

Sediments are important source of nutrients in many water bodies and nutrient loads in many ways result from the

waters where sediments are more easily disturbed by fractions of nutrients from the sediments enter the water

column under reducing conditions. These nutrients cause eutrophication (Kiely, 1998).

Eutrophication is the enrichment of waters by inorganic plant nutrients. The nutrients are usually nitrogen and

phosphorus and these result in an increase in primary productivity. This is artificial enrichment which has been

termed cultural eutrophication. Cultural eutrophication is unnatural and can pose danger to the human societies,

though its occurrence is as a result of human activities. Cultural eutrophication causes pollution of aquaticecosystem leading to the death of aquatic lives such as the plants, fishes and other aquatic organisms that make useof oxygen, thus reducing the recreational value of the lake (Joanne et al.,2007).

There are a number of factors affecting the occurrence of eutrophication, firstly, the nutrient or trophic status of the

water body; secondly, the characteristics of the water body example size, water residence time and thirdly, its

susceptibility to temperature and oxygen stratification and whether it is a monomeric or dimictic lake (Kiely, 1998;

Purcel, 2005). The degree of productivity can be classified according to the annual mean level of phosphate entering

a system and the annual mean production of plant growth in the form of chlorophyll-a.

The study was carried out to assess the status of exchangeable ctaions and anionic pollution of the river sediment

and their relationship with the industrial discharges over a period of time.


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Eze, V.C. and G.C. Okpokwasili: Continental J. Environmental Sciences 4: 36- 43, 2010

MATERIALS AND METHODSStudy Area

The Okpoka - Woji River is situated in the coastal environment of the Niger Delta. It arises from the bifurcation to

the left of the Okpoka River, which drains into bonny river. The area has a mean water depth of 4.8m, which is tidal

and gradually transits from fresh to the salt water at the head. The fresh water biotope flows unidirectionally

downstream from the Rumuodara swamp forest transversing Port Harcourt - Aba Express Road Bridge through

Rumuogba (Mini-Okoro Police Station) where tidal effects begin, hence the beginning of the incursion of salt water.

(Figure1).

E li ah a m

E as t

-

W e st

R um u

d a ra

Mgbuesilia u

Port H.arc

ourt/Aba

Road

Ex p

re ss w

a y

East

WestRoad

Road

Umurou

R u m u o g b aOldAba

Road

Trans

Amadi

Road

Rumuobiakani

Woji

Oginigba

1

3

4

5

2

Trans

Amadi

-

Umur

ou

Road

Abattoir

Creek

Fed Coll.

Okujagu

Source: Street Guide of Port Harcourt by SPDC 1986

Scale0 500m

ExpresswayMajor Road

Rivers / Creeks

Legend

Fig.1: Map of Woji Creek showing the sampling stations

6Okwuru Ama

Okujagu

AbulomaRoad

Trans

Amadi

Road

Trans Amadi

Industrial Area

Elelenwo

Okpoka

River


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Collection of Sediment SamplesSediment samples were collected from the river at the discharge points once in a month from April 2001- March

2002. The sediment samples were collected using soil grab and were put in sterile black polythene bags. All the

samples were analyzed immediately on reaching the laboratory.

Chemical Reagents

Chemical reagents used in the study were of analytical grade and were products of BDH chemicals, Pooles,

England, Sigma Chemical Company, St. Louis, Missouri, U.S.A and Hach Company Ltd. Colorado, U.S.A.

Determination of Exchangeable Cations

The method for the determination was adopted from APHA (1998). The sediment samples were first extracted using

IN ammonium acetate solution. This was done by weighing 5g of sieved air dried samples and adding to 30ml of the

extracting solution in a tube. This was shaken on a mechanical shaker for two hours. They were then centrifuged for

five minutes and the supernatant carefully decanted into a 100ml volumetric flask. This was then made up to the

mark with the extracting solution. The exchangeable cations of the extract were determined using Unicam Atomic

Absorption Spectrophotometer, Model 969.

Determination of the Anions

The anions determined were nitrate, nitrite, ammonia, ammonium, sulphate, phosphate.

The nitrate was determined using the Cadmium reduction method after extraction with distilled water while the

nitrite was determined using the diazotization, NED rapid method. The method of nitrate extraction in the sediment

was employed for nitrite. The Nessler reaction method was employed for the determination of ammonia after

extraction with water. The Ascorbic acid method was used for the determination of phosphate after extraction using

Bray No. 1 solution. The Barium chloride (turbidimetric) method was employed in the determination of sulphate

after extraction using Morgans solution. The method used for determination of sulphate was the Iodimetric titration

method. The methods for the determination of the anions were adapted from APHA (1998).

Statistical Analysis

The statistical tools used were analysis of variance (ANOVA) and standard deviation adapted from Agwung-

Fobellah (2007).

RESULTS

The changes in the exchangeable cations namely calcium, magnesium, potassium and sodium are shown in Figures

2a to 2d. It was generally observed that the mean values for the exchangeable cations were higher in the rainy season

months than in the dry season months. The ANOVA, P > 0.05 showed that there was no significant difference in the

mean values between the rainy and dry season months for calcium and sodium. However the ANOVA, P < 0.05

showed that there was significant difference in the mean values between the rainy and dry season months for

magnesium and potassium. The ANOVA P > 0.05 showed that there was no significant difference in the mean

values among the stations for potassium. However the ANOVA, P < 0.05 shows that there was significant differencein the mean values for other exchangeable cations.


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0.0

500.0

1000.0

1500.0

2000.0

2500.0

Stn 1 Stn 2 Stn 3 Stn 4 Stn 5 Stn 6

Stations

Calcium(mg/Kg)

Rainy Dry

0.0

200.0

400.0

600.0

800.0

1000.0

1200.0

1400.0

1600.0

1800.0


Stations

Potassium(mg/Kg)

Rainy Dry

0.0

1000.0

2000.0

3000.0

4000.0

5000.0

6000.0


Stations

Magnesium(mg/Kg)

Rainy Dry

0.0

20000.0

40000.0

60000.0

80000.0

100000.0

120000.0


Stations

Sodium(mg/Kg)

Rainy Dry

Fig. 2: Changes in the monthly mean values of calcium, potassium,

magnesium and sodium levels of Okpoka-Woji River sediment

across the stations.

2a

2b

2c2d


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The seasonal changes in the nitrate, nitrite and ammonia are shown in Figures 3a to 3c. Their mean values werehigher in the dry season months than in the rainy season months. The ANOVA, P > 0.05 showed that there was no

significance in their mean values between the dry and rainy season months. However, the ANOVA, P < 0.05

revealed that there was significant difference in their mean values among the stations.

0

40

80

120

160


Stations

Nitrate(mg/Kg)

Rainy Dry3b

0

10

20

30

40

50


Stations

Ammonia(m

g/Kg)

Rainy Dry

Fig. 3: Changes in the monthly mean values of nitrite, nitrate and ammonia

levels of Okpoka-Woji River sediment across the stations.

3c

0

20

40

60

80

100

120


Stations

Nit

rite(mg/Kg)

Rainy Dry

3a


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The changes in the ammonium, sulphate, sulphite and phosphate are shown in Figures 4a to 4d. The mean values forammonium were higher in dry season than in the rainy season months. The ANOVA P > 0.05 showed that there was

no significant difference in the mean value between the dry and rainy season months. The ANOVA, P < 0.05

showed that there was significant difference in the mean values among the stations.

The mean values for sulphate and sulphite were higher in the dry season months except in stations 1 and 2 where the

mean values were higher in the rainy season months. The ANOVA P < 0.05 showed that there was significant

difference in the mean values between the dry and rainy season months and also among the stations for sulphate. But

the ANOVA, P > 0.05 revealed that there was no significant difference among the stations for sulphite.

The mean values for phosphate were higher in the rainy season months for stations 1, 5 and 6 while the mean values

were higher in the dry season months for stations 2,3 and 4. The ANOVA, P > 0.05 showed that there was no

significant difference in the mean values between the dry and rainy season months and also among the stations.

0

5

10

15

20

25

30

35

40

45


Stations

Ammonium(mg/Kg)

Rainy Dry

0.0

2.0

4.0

6.0

8.0

10.0

12.0

14.0


Stations

Phosphate(mg/Kg)

Rainy Dry

0.0

2.0

4.0

6.0

8.0

10.0

12.0


Stations

Sulphate(mg/Kg)

Rainy Dry

0.0

1.0

2.0

3.0

4.0

5.0

6.0

7.0

8.0

9.0


Stations

Sulphite(mg/Kg)

Rainy Dry

Fig. 4: Changes in the monthly mean values of ammonium, phosphate,

sulphate and sulphite levels of Okpoka-Woji River sediment across

the stations.

4a4b

4c 4d

DISCUSSION

The exchangeable cations namely calcium, magnesium, potassium and sodium as determined during the study

period were observed to have high values. The domestic and industrial discharges into the river help in increasing

their concentration in the sediment. Decomposing vegetable matter has been reported to rapidly release potassium

(Tesarova, 1976; Ezeala, 1984). The high values of these parameters in the rainy season months could be as a result


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of the deposition of these parameters in the sediment from effluents through runoffs thereby increasing theirconcentration (Izonfuo and Bariweni, 2001; Eze and Okpokwasili, 2008).

The essential nutrients, nitrate and phosphate were observed to have high values and also higher in the dry season

than the rainy seasons months. It has been observed that these nutrients enter the aquatic habitat through urban

sewage effluent discharge which may be in the form of treated or untreated sewage, agricultural activities, especially

animal wastes and fertilizer and settle in the sediment thereby increasing the levels (Kiely, 1998). The pollution

enters as a point source or carried from diffuse sources in their catchments. It has also been observed that both

nitrogen and phosphorus are highly particle reactive and most of them when discharged into water bodies are

deposited in bottom sediments incorporated into organic matter. Here bacteria decompose organic matter, through

oxygen and sulphate reduction, liberating nitrogen and phosphorus to pore water and overlying water (Kiely, 1998;

Parry, 2002).

Phosphorus exchanges with bottom sediment. It is one of the key elements in aquatic chemistry and is thought to be

limiting nutrient in the growth of algae under many conditions. Exchange with sediments play a role in making

phosphorus available for algae and therefore contributes to eutrophication (Manahan, 2001). He also reported that in

some waters receiving heavy load of domestic or industrial wastes, inorganic polyphosphate for example, from

detergents may be present in sediment. Runoff from fields where liquid polyphosphate fertilizer has been used might

possibly provide polyphosphates sorbed in sediment.

Nitrite, ammonia and ammonium are minor nutrients and had high values. They are also transported from land to

water in runoff and now become deposited in the sediment. Ammonia had been observed to be responsible for

reducing nitrate to nitrite (Manahan, 2001).

The pollution of the river sediment by the exchangeable cations and anionic pollutants is therefore attributed to the

industrial effluents from the industries operating within the vicinity of the river.

ACKNOWLEDGEMENTI sincerely thank the management and staff of Quality Control andTesting Laboratories Limited and my wife

Virginia C. Eze and children Chukwuemeka, Nneoma and Ugochukwu for their co-operation, assistance and

understanding in ensuring the completion of this work.

REFERENCES

Agwung-Fobellah, D. (2007). Research Orientation and Thesis Compilation: A Guide for Biological and Health

Sciences, Ark of Wisdom Publishers, Aba, Nigeria; 172 183.

American Public Health Association (APHA), (1998).Standard Methods for Examination of Water and Wastewater,

20th

edition, Washington, DC.

Ezeala, D.O. (1984). Changes in the nutritional quality of fermented cassava tuber meal, Journal of Agricultural

Food Chemistry; 32: 487 469.

Eze, V.C. and G. C .Okpokwasili, (2008). Ecodynamics Of Exchangeable Cations and Organic Pollutants in a Niger

Delta River receiving Industrial Effluents, Continental Journal of Applied Sciences; 3: 103- 113

Izonfuo, L.W.A. and Bariweni, A.P. (2001). The effects of urban runoff water and human activities on somephysicochemical parameters of the Epie Creek in the Niger Delta,Applied Science and Environmental Management;

5(1):47 55.

Joanne, M.W., Linda, M.S. and Christopher, J.W. (2007). P rescott, Harley and Kleins Microbiology, 7th

edition,

McGraw-Hill Company, New York; 628 664.


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Kiely, G. (1998). Environmental Engineering, International edition, McGraw-Hill International Limited, London,UK.

Manahan, S.E. (2001). Fundamentals of Environmental Chemistry, 2nd

edition, CRC Press Ltd., Florida; 124 129.

Parashiva-Murthy, A.S. and P errel, R.E. Jr. ( 1972). Distribution of major Cations in EstuarineSediments; Class and Clay Minerals; 21: 161 -129.

Parry, D.I. (2002). Southern Gulf Environmental Information Program sediments in an estuary in Sierra Leone,

West Africa,Marine Biology; 35:275 286.

Purcel, P. (2005). Principles of Environmental Microbiology, Parenties Publishers Ltd, Ghana; 98 115.

Shell Petroleum Development Company (SPDC), (1986). Street Guide of Port Harcourt.

Tesarova, M (1976). Litter production and disappearance in some alluvial meadows (preliminary results), Folia,

Gobos, Phytotax, Prahia; 11: 63 74.

Received for Publication: 26/05/2010

Accepted for Publication: 20/06/2010

Corresponding Author:

Eze, V.C.

Department of Microbiology, University of Port Harcourt

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