African
Journals Online
Global Journal of Environmental Sciences
Volume 2 Number 2 2003
ABSTRACTS
Toxicity
of substituted benzene derivatives to four chemolithotrophic bacteria isolated
from the New Calabar River.
*L. O. Odokuma and S. I. Oliwe
Department Of Microbiology, Faculty Of
Science, University Of Port Harcourt.
Abstract
The toxicity of benzene, hydroxylbenzene (phenol), chlorobenzene,
methylbenzene (toluene) and dimethylbenzene (xylene) to four chemolithotrophic
bacteria (Nitrosomonas, Nitrobacter, Thiobacillus and Leptothrix isolated from the New Calabar
River water was investigated. The static method for acute toxicity assessment
was employed. Mortality within a period of 5 hours exposure to toxicant was the
index for assessment. Toxicity of the chemicals to the bacteria decreased in
the following order: phenol > xylene > benzene > chlorobenzene >
toluene for Nitrosomonas,
chlorobenzene > phenol > benzene > toluene > xylene for Nitrobacter, phenol > chlorobenzene
> benzene > xylene > toluene for Thiobacillus,
while phenol > chlorobenzene > xylene > toluene > benzene was for Leptothrix. Combining the results above
the toxicity of the chemicals to the test organisms decreased in the order
phenol > chlorobenzene > benzene > xylene > toluene. Sensitivity of
the bacteria to the test chemicals decreased in the order Nitrosomonas > Leptothrix
> Thiobacillus > Nitrobacter. Toxicity of the methyl and
dimethyl substituted derivatives of benzene was probably a function of the
genetic make up of the bacteria. The toxicity generally decreased with
increased methyl substitution in the case of Nitrobacter and Thiobacillus,
but increased with increased methyl substitution in the case of Nitrosomonas and Leptothrix. Hydroxyl and halogenated substituted derivatives were
more toxic than methyl substituted derivatives. These results indicate that
wastes containing hydroxyl and chlorosubstituted derivatives of benzene may
pose a greater toxicity problem to microbiota in the New Calabar River than
wastes containing methyl-substituted derivatives. The nitrification stage of
the nitrogen cycle will also be greatly impaired in the presence of these
groups of chemicals in the river.
Key Words:
Chemolithotrophic bacteria, Toxicity, Sensitivity, Benzene derivatives, New
Calabar River.
Temperature
and its variations in birth rates and sex ratio in Greater Yola, Nigeria
Ambrose
A. Zemba
Geography Department, Federal University of Technology, P.M.B. 2076,
Yola, Nigeria.
Abstract
The relationship between
birth rates, sex ratio and temperature in Yola has been investigated. Data on
temperature and births, for 12 years (1990-2001), were collected from Federal
Meteorological Department, Yola and Federal medical Centre, Yola respectively.
Average mean monthly births and temperature data for the period of study were
analyzed and subjected to statistical test. Also, mean monthly data, nine
months before the births of the children whose birth records were used for this
study, were computed for three years. The Mean monthly birth records and their
corresponding temperature values, for the 3 years, were subjected to
correlation statistical test to find out the relationship between them. The
results have shown that there is negative relationship between birth rates and
temperature. That is, rates of conceptions among women generally, increase
during relatively low temperature periods and vice versa. While female birth
rates are negatively related with temperature, the reverse is the case with
male births. This implies that the ratio of female birth decreases with
increasing temperature whereas male births increase when temperature is higher.
The paper finally emphasizes the need to minimize the effects of high temperature
in our living environments by way of ensuring adequate circulation of air.
KEYWORDS: Temperature,
Birth rate, Sex ratio, Conception, Population.
Studies on physico – chemical properties of pond water in relation to
zooplanktonic organisms of the ponds of Oso-Edda in Afikpo, Ebonyi State
Nigeria
Wokem Gloria .N. and Udonsi
Jonathan K.
Department of Medical Laboratory Sciences, Rivers State University of
Science and Technology, P.M.B. 5080 Port Harcourt, Nigeria.
DEPARTMENT OF ANIMAL AND
ENVIRONMENTAL BIOLOGY,
UNIVERSITY OF PORT HARCOURT,
P.M.B. 5323, PORT HARCOURT, NIGERIA.
Abstract
A
study on the physico-chemical status and Checklist of Zooplankton of the ponds
of Oso – Edda in Afikpo, Ebonyi State, Nigeria was carried out in eight
representative communities and a bore hole water which was a control study. The
results showed that the mean of physico-chemical properties obtained were for
the littoral zone of the twelve ponds (P1 – P12) studied and that these
properties exhibited spatial and temporal variations. The mean abundance of
zooplankton ranged from 3 to 78 orgs/Litre. There were more than seven genera
of zooplankton with about ten species. The order Copepoda were the dominant
zooplankton with the sub order Cyclopoida occurring in all the studied ponds.
Other environmental indicators species identified include Moina micrura,
Branchionus callcy florus, Amphipoda, Calonoida, Chironomidae Spp and the
unidentified. The major abiotic factors influencing zooplankton population were
principally climatic factors, pH, salinity, alkalinity, inorganic ions some of
which were responsible for high conductivity.
Key Words: Physico-Chemical,
Zooplankton, Guinea Worm.
Primary
biodegradation and mineralization of hair shampoos in fresh, brackish and marine
waters of the Niger Delta
*Odokuma, L. O. and Otokunefor. K.
Department of Microbiology, Faculty of
Science, University of Port Harcourt
Abstract
Two methods, the methylene
blue active stain (MBAS) river die away method for monitoring primary biodegradation
of surfactants and the ultimate biodegradability method for monitoring
mineralization of the total biodegradable organic component in a compound were
employed to determine the biodegradability of three hair shampoos, (Hair fruit
shampoo, New Goldmax super antidandruff shampoo and Goldmax antidandruff
shampoo) for a 28-day period. Sodium dodecyl sulphate (SDS) served as the
reference chemical. After 28 days, the percentages of MBAS remaining in fresh,
brackish and marine waters respectively were: for hair fruits shampoo, 83.8, 95
and 2; for New Goldmax super antidandruff shampoo, 83.8, 80 and 12.5; for
Goldmax antidandruff shampoo, 66.7, 59.5 and 17.3. However, the percentages of
mineralization were: for carbon of hair fruit shampoo, 13.5, 8.6 and 95.2; for
carbon of New Goldmax super antidandruff shampoo, 53.9,72.9 and 99.7, and for
carbon of Goldmax antidandruff shampoo, 90.2, 83.2 and 99.8. Primary
biodegradation and mineralization of SDS was independent of water type. The
extent of both primary biodegradation and mineralization followed the trend:
marine water > brackish water = fresh water. These results indicated that
the extent of Primary biodegradation and mineralization was greatest with
marine water of Bonny estuary and the two test methods produced the same
results.
Key words; Primary
biodegradation, Mineralization, Shampoos, Freshwater, Brackish water, Marine
water.
Effects of the amendment of
crude – oil polluted soil on fungal population
C. I. Onuoha
Department of Plant Science and Biotechnology, Faculty of Science, Imo
State University Owerri.
Arinze. A. E.
Department of Plant Science and Biothecnology Faculty of
Science University of Port Harcourt.
Ataga, E. A
Department of Plant Science and Biothecnology Faculty of
Science University of Port Harcourt.
Abstract
The population of fungal
propagules in crude oil polluted and amended soil under simulated condition was
investigated. The result showed an initial decrease in the population of fungal
propagules, then a rapid increase and finally, a gradual reduction in the
number of propagules. An exception to this was in sawdust-amended soil that
recorded a rapid increase in fungal population from the beginning up to the 4th
week. The polluted and unremediated soil showed a comparatively low fungal
population up to the 3rd week before a gradual increase. The soil
amended with wood ash showed a comparatively low population of fungal
propagules throughout the study.
Keywords: Crude
oil, pollution, soil amendment, fungal population.
Heavy metal biosorption by
three bacteria isolated from a tropical river
*Odokuma L.O. and Abah A.E
Department of Microbiology, Faculty of
Science, University of Port Harcourt.
Abstract
Bioaccumulation
(bioconcentration) of four heavy metals cadmium, lead, zinc and nickel by three
bacteria Bacillus, Staphylococcus and Pseudomonas as a tool for the decontamination of heavy metal
impacted aquatic systems was investigated . The bacteria were obtained from the
New Calabar River. Monitoring of the physicochemical parameters of the river
water and sediment revealed upstream downstream increases in their levels.
Ranges for riverwater parameters were temperature (23 to 270C), pH
(5.34 to 5.84), alkalinity (12.0 to 18.8mg CaC03/L), dissolved
oxygen (6.24to 6.92mg/L), total suspended solids (1.13 to 1.61mg/L),
conductivity (2.15 to 2.39 mS/m), chloride
(3.0 to 10.20mg/L), biochemical oxygen demand (2.0 to 2.5mg/L) and chemical
oxygen demand (4.0 to 10.0mg/L). Ranges for sediment parameters were
temperature (20 to 250C), pH (5.3 to 6.97), conductivity (2.55 to
4.22 mS/m), dissolved
oxygen (3.2 to 4.22mg/L), chloride (3.5 to 15.3mg/L), biochemical oxygen demand
(5.5 to 10.5mg/L) and chemical oxygen demand (20.7 to 100.6 mg/L). River water
heavy metals levels were lower than sediment levels. The river water ranges
were; Cu (0.01 to 0.05mg/L), Pb (0.01 to 0.02mg/L), and Zn (0.01 to 0.07 mg/L).
Sediment heavy metal ranges were Cu (1.09 to 1.45 mg/L), Pb (0.03 to 0.07mg/L)
Cd (nd to 0.009mg/L) and Zn (0.27 to 1.27mg/L). The percentage accumulation of
heavy metals by Bacillus, Staphylococcus and Pseudomonas after 24h
of exposure to heavy metals were Cadmium; 68.6% , 58.4% and 28.3%, Nickel;
94.5% , 85.7% and 90.8%, Lead; 91.6%, 68.1% and 52.9%, Zn; 71.6% 72.1% and
77.0% respectively. The ease of bioaccumulation of the metals by bacteria
showed the following trend N1 > Zn > Pb > Cd. Cadmium was
the most toxic of the metals to the bacteria. Lead and Zinc displayed similar
levels of toxicity, while Nickel was the least toxic. Bioaccumulation potentials
of the three bacteria indicated that Bacillus
showed the highest potential this was followed by Staphylococcus while Pseudomonas
showed the least potential. These results indicate that bacteria especially Bacillus may be employed in the
bioremoval of heavy metals from tropical aquatic environments impacted with
heavy metals.
Key Words:
Bioaccumulation, Bioconcentration Heavy metals, Decontamination, Bacteria.
Potential
benefits and inherent dangers in cropping municipal waste dump sites – case studies
in the City of Ibadan, Nigeria
Taiwo,
L.B.1, A.R. Omonode2, M.O. Akande1 and J.A.
Adediran1
1Institute
of Agricultural Research and Training, Obafemi Awolowo University,
Moor Plantation, P.M.B. 5029, Ibadan,
Nigeria.
2Department
of Agronomy, University of Ibadan, Ibadan, Nigeria.
Abstract
The benefits derivable to
crops from the high fertility status of municipal wastes dump sites and the
dangers of heavy metal accumulation in crops planted therein were examined in
three municipal refuse dumpsites namely, [Eleiyele
(Site 1), Ring Road, (Site 2) and Bere (Site 3)] in Ibadan, Nigeria.
The response of maize (Zea mays) to the soil nutrients and
heavy metals were examined in the greenhouse and in the field. The plant
nutrients in the three dump sites were quite adequate for maize growth and
development but no germination of the test crop was observed in Site 3. Water
(absorbed) and potassium nitrate (KNO3) (exchangeable) fractions of
the heavy metals in the soils of the three sites were lower than the critical
levels considered to be phytotoxic. However, the total extractable copper (Cu)
(20.42mgkg-1) and zinc (Zn) (39.44mgkg-1) in the soils
were higher in Site 3 than in the other dump sites. Site 3 soil also contained
the highest population of cellulose degrading microorganisms. The
concentrations of the heavy metals in plant tissue planted in the greenhouse
experiment were low but high in plant tissue harvested in the field. Refuse
dump site soils are important in Ibadan agricultural production but it is necessary
that cropping is preceeded by soil test to determine nutrient and heavy metal
concentrations.
Keywords:Soil nutrients; Fertility status; Heavy
metals; Municipal wastes
Seasonal
variation in water quality of the Calabar River: Influence of tidal and coastal
activities
E. R. Akpan1, H. E. Ekpo2 and U. J. Ekpe2
1Institute of Oceanography, University of Calabar, P
. M. B. 1115, Calabar, Nigeria
2Department of Chemistry, University of Calabar,
Calabar, Nigeria.
Abstract
Water quality of the Calabar River Estuary was measured during
November, February and May representing the major climatic conditions and
during high tide, low tide and mid-tide representing the most important tidally
forced hydrodynamic conditions in the estuary. The lowest water quality
(<70%) was observed at the bottom levels in May during the wet season. Water
quality changes over a cross section transect of the River at Duke Town Harbour
did not indicate any significant influence of coastal activities and land use.
The homogeneity in water quality is attributed to the high tidal activity.
Ionic adsorption/desorption as well as material sedimentation/resuspension
induced by tides are the major factors of variability in water quality of the
estuary. Any development, which has the potential to modify these processes,
may result in large-scale water quality changes with dire consequences on water
uses and biological conservation.
Key Words: Water quality, Tidal regimes, Seasonality, Calabar
River Estuary, Nigeria.
Effect
of waste engine oil on phytoplankton of the Calabar River Estuary, Nigeria
1Ekom R. Akpan: Institute of Oceanography,
University of Calabar, P. M. B. 1115, Calabar, Nigeria.
2Anietie I. Frank: Department of Science
Technology, University of Calabar, Calabar, Nigeria.
Abstract
The effect of waste lubrication oil on phytoplankton of the Calabar
River Estuary has been examined under static conditions in the laboratory.
Significant growth inhibitions and growth pattern alterations as well as
susceptibility to bacterial attack were observed in the dominant diatom
species- Actinocyclus and Aulocadiscus species during a 5 day
exposure to concentrations of the oil ranging from 14.5 to 58 ppm. Oil
treatment also resulted in growth enhancements in nanoflagellate population. Considering
the importance of diatoms to organic carbon and oxygen supply in the Calabar
River and associated Cross River Estuary, their destruction by oil
and/succession by flagellates will result in negative consequences for
fisheries and overall ecology of the system. The high toxicity of the waste oil
even at low concentrations of total hydrocarbons calls for a re-appraisal of
the permissible levels of total hydrocarbons in Nigerian inland waters
currently put at 10 ppm.
Key Words: Waste
lubricating oil, Phytoplankton, toxicity, Calabar River Estuary.
The impact of climate
change and anthropogenic factors on desertification in the semi-arid region of
Nigeria
Odjugo, A.O. Peter and Isi A. Ikhuoria
Department of Geography and Regional Planning, University of Benin,
P.M.B. 1154, Benin City, Edo State, Nigeria
Abstract
This paper examines the
impact of climate change and anthropogenic factors on desertification in the
semi-arid region of Nigeria. Climatic data (Temperature and rainfall) for 52
years (1950 – 2001) from 25 meteorological stations were collected and
analysed. Questionnaires were also used to solicit respondents' perception on
the causes, effects and solution to desertification in Nigeria. The data were
computed and analysed using the square method, maps and bar graphs.
The results among others
show that while temperature has been on the increase, rainfall has been
decreasing. The continued aridity and pressure on the land from farming,
grazing and indiscriminate bush burning have led to southward desert
encroachment. Currently, approximately 22.6% of the country's landmass is being
affected by desertification. The desertification process has resulted in
southward migration of sand dunes, water scarcity, reduction in crops'
production, ecological degradation and emigration of people and animals.
Integrated efforts from the Local Communities, States and Federal Government
together with NGOs and International Bodies to combat desertification through
massive afforestation, enlightenment campaign, avoidance of indiscriminate bush
burning, reduction in deforestation, overgrazing and overcropping among others
are recommended.
Key
Words: Climate Change,
Sand dunes, hydrothermal, Desertification and Afforestation.
Tolerance
of bacteria to toxicity of heavy metals in the New Calabar River
L. O. Odokuma and S. O. Ijeomah
Department of Microbiology, University of Port-Harcourt, Port-Harcourt.
Abstract
The tolerance to salts of
four heavy metals by pure and mixed cultures of four heavy metal–resistant
bacteria, Bacillus, Proteus, Alcaligenes and Arthrobacter,
isolated from the New Calabar River water was investigated. Heavy metal
resistant bacteria were isolated from river water using nutrient agar
supplemented with 20mg of salts of
heavy metals per milliliter. Salts of heavy metals employed were CuCl2.2H20,
ZnS04.7H20, CdCl2.6H20 and Pb304.
Bacillus was the most tolerant to the
four heavy metal salts while Proteus showed
the highest degree of sensitivity. The 24h LC50 of CuCl2.2H20
and ZnSO4.7H20 to Bacillus,
Alcaligenes, Arthrobacter and Proteus
were 100mg/L, 0.3mg/L, 0.5mg/L, 0.3mg/L, and 1.0mg/L, 0.4mg/L, 0.07mg/L,
and 0.008mg/L, respectively. The 24h LC50 of CdCl2.6H20
and Pb304 to Bacillus,
Alcaligenes, Arthrobacter and Proteus
were 100mg/L, 100mg/L, 0.06mg/L, 0.07mg/L, 0.02mg/L, 0.2mg/L, 0.02mg/L and
0.07mg/L respectively. Hydrated Copper Chloride (CuCl2.2H20),
CdCl2.6H20 and Pb304 were
significantly less toxic to these organisms at 1% probability level, compared
to ZnS04.7H20. Levels of heavy metals in river water
ranged from <0.001 to 0.06mg/L for cadmium, 0.01 to 1.2mg/L for copper,
0.013 to 0.48mg/L for zinc, 0.007 to 0.44mg/L for iron. Vertical variation in
the concentrations of heavy metals in the river water was significant at 1%
probability level. River sediment concentrations of heavy metals were
significantly greater than river water levels at 5% probability level. Dry
season levels of heavy metals were significantly greater than rainy season
levels at 5% probability level. Heavy metal concentrations of some industrial
effluents discharged into the river ranged from 0.02 to 0.07mg/L for cadmium,
0.01 to 0.09mg/L for copper, 0.09 to 0.50mg/L for lead, 0.26 to 0.47mg/L for
zinc and 0.42 to 2.31mg/L for iron. Results suggest that all the four heavy metal
salts were toxic to river water micro flora. Hydrated zinc chloride (ZnCl2.7H20)
was the most toxic to the bacteria while Pb304, CdCl2.6H20
and CuCl2.2H20 displayed similar levels of toxicity.
Results also indicated that the heavy metal content of the industrial effluents
sited along the New Calabar River water may pose toxicity problems especially
to the abundance and diversity of the existing river water microflora.
Keywords: Tolerance,
Sensitivity, Resistance, Toxicity, Concentration.
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