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Mangrove Ecosystem Recovery and Restoration from Oil Spill in the Niger Delta: The GIS Perspective

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The study evaluated the changes in the land cover of the mangrove ecosystem in Niger Delta from 1986 to 2008. It also assessed the time-frame required for mangrove vegetation in the study sites to recover from oil spill impact with a view to developing a GIS-based model for mangrove vegetation recovery in the Niger Delta. The study integrated both primary and secondary data sources. The data included ground truthing technique with the aid of Global Positioning System (GPS), satellite imagery, oil spill record and oil spill map. Two sites were purposively selected for the study due to the nature of the terrain (non-remediated and remediated site). The result showed that it took 13 to 14 years for mangrove vegetation on non-remediated site to recover while it takes only 7 years for complete vegetation recovery on the remediated site from the impact of oil spillage. The results further showed a downward trend of mangrove vegetation recovery from 1986 to 2000 and upward trend between 2000 and 2007 in the GIS-based model. The study concluded that oil spillage had serious impact on the health and growth of mangrove vegetation.
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Research Article
Orimoogunje and Ajibola-James, Geoinfor Geostat: An Overview 2013, S1
http://dx.doi.org/10.4172/2327-4581.S1-017
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Mangrove Ecosystem Recovery
and Restoration from Oil Spill
in the Niger Delta: The GIS
Perspective
Oluwagbenga OI Orimoogunje1* and Opeyemi Ajibola-James2
Abstract
The study evaluated the changes in the land cover of the mangrove
ecosystem in Niger Delta from 1986 to 2008. It also assessed the
time-frame required for mangrove vegetation in the study sites to
recover from oil spill impact with a view to developing a GIS-based
model for mangrove vegetation recovery in the Niger Delta. The
study integrated both primary and secondary data sources. The
data included ground truthing technique with the aid of Global
Positioning System (GPS), satellite imagery, oil spill record and oil
spill map. Two sites were purposively selected for the study due to
the nature of the terrain (non-remediated and remediated site). The
result showed that it took 13 to 14 years for mangrove vegetation
on non-remediated site to recover while it takes only 7 years for
complete vegetation recovery on the remediated site from the
impact of oil spillage. The results further showed a downward trend
of mangrove vegetation recovery from 1986 to 2000 and upward
trend between 2000 and 2007 in the GIS-based model. The study
concluded that oil spillage had serious impact on the health and
growth of mangrove vegetation.
Keywords
Land cover; Mangrove ecosystem; Multi-Date Satellite Imagery;
GIS modelling
*Corresponding author: Oluwagbenga OI Orimoogunje, Department of
Geography, Obafemi Awolowo University, Ile-Ife- 220005, Nigeria, Tel:
+2348035855946; E-mail: orimoogunje2@yahoo.com
Received: June 01, 2013 Accepted: September 16, 2013 Published:
September 24, 2013
has contributed to the reduction in Africa’s mangrove coverage by
55% [6]. Ifeadi and Nwankwo, [7] and Awobajo [8] revealed that
the highest incidence of oil spills occurred in the mangrove swamps
zones and near o shores areas of the Niger Delta which was shown
in an analysis of oil spillage statistics in Nigeria during the period
1976 to 1988. Crude oil spills continue to be a notable threat to the
conservation of the rich mangrove eco-region of the Niger Delta in
Nigeria. According to Ebuehi et al. [9] mangroves areas are the most
productive and sensitive areas in the ecosystem. e predominant
and vulnerable mangrove species in the Niger Delta are Rhizophora
racemosa, Rhizophora mangle (red mangrove), Avicennia germinans
(white mangrove) and Languncularia racemosa (black mangrove).
Mangroves have traditionally provided a variety of plant products,
sh and shellsh for local communities [10]. ey also provide services
such as coastal stabilization, and food chain support for near-shore
sheries. In recent decades there has been increased conversion for
uses which do not sustain the mangrove habitat, such as large-scale
sh culture ponds and industrial salt production, and there is concern
about the resulting loss of mangroves [10]. Nevertheless, all these uses
may be aected following oil spills and need to be considered during
the contingency planning process.
Oil spillage is a major environmental problem in Nigeria.
Between 1976 and 1996 Nigeria recorded a total of 4835 oil spill
incidents, which resulted in a loss of 1,896,960 barrels of oil to the
environment. In 1998, 40,000 barrels of oil from Mobil platform
of the Akwa-Ibom coast were split into the environment causing
severe damage to the coastal environment. Oil spillage has led to
very serious pollution and destruction of ora, fauna and resort
centres, pollution of drinkable water, destruction of properties and
lives along the Nigerian coast. Oil spillage has also caused regional
crisis in the Niger Delta. Factors responsible for oil spillage in the
zone are; corrosion of oil pipes and tanks, sabotage, port operations
and inadequate care in oil production operations and engineering
drills. e consequence is the massive oiling of the environment and
destruction of vulnerable ecological units [9-11]. is is more so in
the mangrove where tidal eects facilitate dispersion of spills. It has
been noted that mangroves are highly susceptible to oil pollution
[12]. e impact of oil spill on mangroves is a function of a number of
factors. According to Lewis [13] there are four factors: rst the type of
spilled oil, second the quantity of spilled oil reaching the mangroves,
third the quantity remaining aer any clean-up eort and fourth the
various physiographic types of mangrove aected. Other factors are
length of mangrove’s exposure to spilled oil [5], site conditions [14]
and the remediation technique employed [12]. Observations from
many spill events around the world have shown that mangrove suers
both lethal and sub-lethal eects from oil exposure [5]. Mangrove
forests are particularly dicult to protect and clean up once a spill has
occurred. is is because they are physically intricate and relatively
hard to access [10]. Each of these considerations contributes to the
overall assessment that mangrove forests are a habitat at risk from
oil spills.
e Remediation by Enhanced Natural Attenuation (RENA)
technique established in the oil spill response plan of Shell Petroleum
Introduction
Mangrove forests are the dening feature of the coastal
environment in many tropical regions. ey are the dominant
ecosystem along the sheltered shoreline of the Nigerian coast.
Mangroves are vital resource that serves the inhabitants of the Niger
Delta and are areas of active oil exploration in Nigeria. Mangroves
provide logs, fuel wood, charcoal, wood-chips, paper pulp, scaold
poles, piling and construction materials, stakes for sh traps, and
shing platforms, railway sleepers, wood for furniture making and
carvings, materials for roof thatching, bark for tannin, medicinal
products, sugar, alcohol, acetic and dyes [1-3]. According to
Robertson et al. [4] mangroves serve as habitat and breeding areas for
many commercially important sh and crustaceans while it provide
detritus for oshore sheries, controls coastal erosion as well as
maintaining water quality. ey are principal places that are impacted
by oil exploration and associated activities [5], an occurrence that
Citation: Orimoogunje OOI , Ajibola-James O (2013) Mangrove Ecosystem Recovery and Restoration from Oil Spill in the Niger Delta: The GIS Perspective.
Geoinfor Geostat: An Overview S1.
Page 2 of 5
Special Issue 1 • 017
doi:http://dx.doi.org/10.4172/2327-4581.S1-017
Development Company of Nigeria (SPDC) has limited scientic
proof of its eectiveness in mangrove recovery. Remediation by
Enhance Natural Attenuation (RENA) is a land farming treatment
technology for intervention in petroleum hydrocarbon contaminated
soils in the Niger Delta regions [7,15,16]. But the earlier study on
RENA’s eectiveness adopted the rate of hydrocarbon degradation in
soil and swamp; and suitability of contaminants for biodegradation
as major criteria, but lacked considerations of mangrove vegetation
recovery time-frame [17]. erefore, this study attempts to assess the
eectiveness of RENA approach adopted and the time frame required
for mangrove vegetation in the study sites to recover from oil spill
impact.
Materials and Methods
Study area
e study area consists of two sites impacted by single major oil
spill in the mangrove of the Niger Delta (Figure 1). ese sites have
spillage impact of more than 20 km2 and spilled oil quantity more
than 25 barrels. One of the sites was impacted on the 15th June, 1994
and subsequently remediated between 2000 and 2002. e other
was impacted on the 22nd November, 1995 but was not remediated
as at December, 2008 [18]. e remediated site covers about 27.93
km2 lying approximately within Top Le Coordinates: 473414.012E;
78304.938N and Bottom Right Coordinates: 478383.632E;
71709.313N. e Non-remediated site covers about 23.99 km2
lying approximately within Top Le Coordinates: 478797.298E;
87122.644N and Bottom Right Coordinates: 484975.276; 77901.781.
e two sites for the study are in the Rivers State and the SPDC
Eastern division of the Niger Delta in Nigeria. e Niger Delta,
with an area of about 30,000 km2 is rich in biodiversity [19]. e
mangrove plants in the Niger Delta cover approximately 6000 km2
between the inland fresh water zone and the belt of beach-ridges,
which form the seaward boundary [20-22]. e Niger Delta region
has ve species of true mangroves: Rhizohpora racemosa, Rhizophora
harrisonii, Rhizophora mangle, Avicennia africana and Langucularia
racemosa [23], Acrostichum aureum, Conocarpus erectus, and Nypa
fruticans have also been identied as species of plants associated with
mangroves in the Niger Delta [24]. In term of climate, the study area
lies within the Wet Equatorial climate zone where cloud cover is very
high and the coastal parts are under more or less permanent cloud
cover. Sunshine hours are very low with very high relative humidity
most of the year, ranges between 80% in March and greater 90% in
July. Temperature means values range between 24°C and 32°C while
rain falls every month of the year but with a short dry spell between
January and March. Mean annual rainfall ranges from 4500 mm in
Bonny to 2000 mm in Ndoni [25].
Methods
is study utilized data acquired by ground truthing technique
(eld observation) with the aid of Global Positioning System
(GPS) coupled with data sourced from the archive of an oil and
gas exploration company. Two sites were purposively selected for
the study in the Niger Delta (one remediated and the other non-
remediated). e sites selected were based on the history of oil
spillage which impacted more than 20 km2of the study area. Landsat 5
TM of 1986 and Landsat ETM+ of 2000, 2003 and 2007 multi-spectral
sensor of 30 m spatial (pixel) resolution were used to monitor, assess
and contrast the trend of mangrove vegetation recovery from the oil
spill’s impact. e imagery was pre-processed using geo-rectication,
region creation and co-registration techniques embedded in the ER
Mapper (version 7.0.) soware. e image processing techniques
of Normalised Dierence Vegetation Index (NDVI) and Density
Slicing of NDVI Values were used for analyzing the imagery data sets.
Vegetation monitoring by remotely sensed data was carried out using
vegetation indices, which are mathematical transformations designed
to assess the spectral contribution of green plants to multi-spectral
observation [26]. us, the analysis of Mangrove vegetation health
status was attempted using Normalized Dierence Vegetation Index
(NDVI) function, which is given by:
( ) ( ) ( )
DN output NIR R / NIR R= − +
(1)
where,
( )
NIR Near Infrared Band 4=
,
and
( )
R Red Band 3=
of LANDSAT TM and ETM+.
is function exists as an algorithm in the ER Mapper and was
applied to the imagery data set over the study area. e output
NDVI imagery data sets were brought into ArcGIS 9.2 soware
environment by using the “add data” command tab in the window
of the soware. Subsequently, the density slicing analysis was carried
out by employing the capabilities of the GIS soware to partition and
colour code the observed feature on the imagery data set. e density
slicing approach was based on the principle of Electro Magnetic
Radiation. e adopted principle for the land cover classication
is in consonance with the ndings of Budde and Nijmeijer [27] on
spectral signatures of land cover. Based on this theory, a classication
scale was evolved for the study which represents the NDVI values
classication range detailing the land cover classes, their respective
range of NDVI values, colour and RGB (Red, Green, Blue) codes. It
should be noted that the classication range was determined with
the aid of Pseudo-Natural Colour Composite (PNCC) of the data
sets. In eect, the NDVI imagery data set for each acquisition was
classied into 7 distinct clusters of land cover (Creeks & Rivers, Deep
Swamp, Shallow Swamp, Swamp Soil, Stunted Mangrove, Medium
Mangrove, Tall Mangrove, and Very Tall Mangrove) by using the
density slicing approach. Additionally, through the process of re-
classication, generic statistics of Water, Swamp Soil, and Vegetation
were generated from the initial 7 clusters’ statistics.
Figure 1: The Study Area in the Nigeria Niger Delta.
Citation: Orimoogunje OOI , Ajibola-James O (2013) Mangrove Ecosystem Recovery and Restoration from Oil Spill in the Niger Delta: The GIS Perspective.
Geoinfor Geostat: An Overview S1.
Page 3 of 5
Special Issue 1 • 017
doi:http://dx.doi.org/10.4172/2327-4581.S1-017
Results and Discussion
Satellite imagery analyses
Table 1 shows the NDVI values for each site for the 4 epochs in
the study area between 1986 and 2007. Table 1 also shows that in 1986
before the oil spills the two sites had equal NDVI average value (0.32),
which indicates equilibrium mangrove vegetation health which is
essential basis for the assessment study. us, the 1986 imagery
represents the base line data for the study. However, the equal NDVI
values obtained do not necessarily represent the optimal vegetation
health status [28,29].
e Table 1 also shows that in 2000 (6/7 years aer the oil spill)
the NDVI value of the non-remediated site (0.27) was less than that
of remediated site (0.30). is shows a decline in the health condition
of the vegetation on both sites and thus suggests the spilled oil as an
inducing factor. It also indicates that the vegetation on the remediated
site was healthier than the one on the non-remediated site. It should
be noted that an information gap exists between 1986 and 2000
due to data inaccessibility. In spite of the information gap, the 0.03
dierence in the NDVI values for the two sites in 2000 coupled
with the fact that remediation was done between 2000 and 2002
may indicate the eectiveness of RENA. is was in support with
Shekwolo [17] argument that if RENA is applied to an oil impacted
site, remediation may be observable within 8 to 12 weeks if moisture
content and nutrient level are appropriate. ey also suggest that a
signicant reduction of the hydrocarbon compounds in crude oil spill
contaminated soil could be achieved within 40 days of application of
RENA. In 2003 the NDVI value of non-remediated site (0.31) was less
than that of remediated site (0.34). is shows that the vegetation on
the remediated site continued to be healthier than that on the non-
remediated site. e value also implies that there was an increase in
the health status of the vegetation on both sites and thus suggests
progressive recovery from the spilled oil impact. e observed 4 units
of improvement in the NDVI value of non-remediated site from 0.27
in 2000 to 0.31 in 2003 seems to be induced by normal rate natural
attenuation. is attenuation would be partly due to the weathering
of spilled oil overtime on the non-remediated site. e weathering
processes might be one or combination of factors like oxidation,
evaporation, dissolution and biological degradation [30]. Freegarde
and Hatchett [31] estimated that an oil-slick of 2.5mm thickness
could be degraded in 100hours of continuous sunlight. Floodgate [30]
opines that up to 50% of spilled oil can be lost through evaporation in
a few hours depending on the original composition of the oil. Bacteria,
yeasts and other microbes attack petroleum and biodegrade it [30].
In 2007 the NDVI value of the vegetation on the non-remediated
site (0.34) was less than that of remediated site (0.36). is indicates
further increase in the health status of the vegetation on both sites.
However, the vegetation on the remediated site was healthier than
that of the non-remediated site. is shows the eectiveness of RENA
in mangrove restoration. Moreover, the NDVI values of remediated
site (0.36) and non-remediated site (0.34) in 2007, which rose above
the baseline values (0.32) in 1986 show that vegetation on the two
sites may have completely recovered from the oil spill impact and
proceeded towards attainment of full physiognomy. is collaborated
Lewis ndings, that from the 10th year upward, complete recovery of
oil impacted mangrove vegetation is attainable [13].
Tables 2 and 3 reveal the land cover area for both sites respectively.
e tall mangrove vegetation class on non-remediated and remediated
sites yielded the most unusual trend pattern between 2003 and 2007
(up-trend). Figures 1 (a) and (b) represent the trend of land cover for
the former and later sites respectively over the 4 epochs, the general
pattern of the trend is quite inconsistent. For instance, on the non-
remediated site, the tall mangrove accounted for 12% of the land
cover in 1986, 15% in 2000, 13% in 2003 and 64% in 2007. Similar
inconsistent pattern was observed in other land cover classes like
medium and stunted mangroves. e ideal pattern for a recovering
vegetal cover area should at least be consistent over time. at is, an
initial downtrend followed by an up-ward trend is expected on a site
impacted with crude oil. is could be inferred from the observation
Lewis on generalized responses of mangrove forests to crude oil [13].
He suggests initial defoliation and death of some sizes of mangroves,
which correspond with the expected downtrend in the area of
vegetal cover. e subsequent recolonization/ reduction in litter fall
correspond with expected uptrend in the area of vegetal cover over
time. e challenge of inconsistency might be due to the thin line
(1 unit dierence) between lower and upper class boundaries of the
NDVI Values Classication.
Range used for the land cover features on the Study Area, coupled
with the close spectral values of similar features like tall, medium
and stunted mangroves. e analysis shows further that the non-
remediated site over the 4 epochs, area covered with water had a
Time-Lapse 1986 Pre-oil
spill 2000 2003 2007
Non-remediated site
(Nov 1995) 0.32 0.27 0.31 0.34
Remediated site (June
1994) 0.32 0.30 0.34 0.36
Table 1: NDVI values for the four Epochs (1986 to 2007).
Land Cover 1986
Km2 %
2000
Km2 %
2003
Km2 %
2007
Km2 %
Creeks and rivers 1.36 6 3.40 14 1.42 6 1.03 4
Deep swamp 3.67 15 4.82 20 2.53 11 0.79 3
Shallow swamp 4.53 19 0.00 00 3.95 16 2.09 9
Swamp soil 4.89 20 6.21 26 5.12 21 4.61 19
Stunted mangrove 3.74 16 2.62 11 4.46 19 0.00 0
Medium mangrove 2.57 12 3.35 14 3.33 14 0.00 0
Tall mangrove 3.23 12 3.59 15 3.18 13 15.47 64
Total 23.99 100 23.99 100 23.99 100 23.99 100
Table 2: Land Cover Area for non-remediated Site for the 4 Epochs.
Land Cover 1986
Km2 %
2000
Km2 %
2003
Km2 %
2007
Km2 %
Creeks and rivers 1.54 6 3.59 13 2.63 9 0.94 3
Deep swamp 2.94 11 3.96 14 0.00 0 2.14 8
Shallow swamp 3.68 13 0.00 0 3.78 14 3.39 12
Swamp soil 5.10 18 8.23 29 9.53 34 6.53 23
Stunted mangrove 5.54 20 4.26 15 0.00 0 0.00 0
Medium mangrove 5.07 18 4.64 17 4.76 17 0.00 0
Tall mangrove 4.06 15 3.25 12 7.23 26 14.93 53
Total 27.93 100 27.93 100 27.93 100 27.93 100
Table 3: Land Cover Area for remediated Site for the 4 Epochs.
Citation: Orimoogunje OOI , Ajibola-James O (2013) Mangrove Ecosystem Recovery and Restoration from Oil Spill in the Niger Delta: The GIS Perspective.
Geoinfor Geostat: An Overview S1.
Page 4 of 5
Special Issue 1 • 017
doi:http://dx.doi.org/10.4172/2327-4581.S1-017
consistent downward trend from 1986 till 2007 from 9.56 km2 (40%)
to 3.91 km2 (40%). e Swamp Soil seems to have an upward trend
between 1986 and 2000. e trend reversed consistently between
2000 and 2007 for three consecutive epochs. e vegetation cover had
upward trend between 1986 and 2007 for four consecutive epochs.
is follows a normal distribution and thus suggests a gradual
recovery of vegetation coverage from the oil spill impact on the non-
remediated site.
Figure 2a and b for the remediated site over the 4 epochs
revealed that the area covered with water i.e. creeks and Rivers, Deep
and Shallow Swamps, seems to have an insignicant downtrend
between 1986 and 2000 from 8.16 km2 (29%) to 7.91 km2 (27%).
Between 2000 and 2003 the downtrend continued but it became
more signicant: 7.91 km2 (27%) to 6.41 km2 (23%). ere was an
upward but insignicant movement of the area trend between 2003
and 2007 from 6.41 km2 (23%) to 6.47 km2 (23%).
From 1986 through 2000 to 2003, the trend of area covered by
Swamp Soil progressively followed an upward course: 5.10 km2 (18%)
to 8.23 km2 (29%) to 9.53 km2 (34%) respectively. However, there
was downtrend between 2003 and 2007 up till 2008: 9.53 km2 (34%)
to 6.53 km2 (23%) to 4.72 km2 (17%). Concerning the vegetation
cover, the amalgamation of Stunted, Medium, and Tall mangroves
coverage had signicant downtrend between 1986 and 2000 from
14.67 km2 (53%) to 12.15 km2 (44%). e downtrend continued,
though insignicant between 2000 and 2003: 12.15 km2 (44%) 11.99
km2 (43%). Between 2003 and 2007, there was a signicant trend
reversal from 11.99 km2 (43%) to 14.93 km2(53%).
Implication of the study
e study shows that there was relatively fast recovery rate and
short recovery period of the vegetation on crude oil impacted site
where RENA was applied. It also shows that complete recovery of
mangrove vegetation was possible between 13 and 14 years, that is
7 years post RENA application, aer the oil spill impact. is was
in agreement with Lewis argument on mangrove complete recovery
period of 10 – 50 years aer oil spill impact. In spite of the armed
possibility of mangrove recovery via RENA, the initial negative
impacts on land, sheries and the ecosystem with consequences on
community livelihood are better imagined than experienced. is has
been of greater concern to the aected communities over the years.
us, zero oil spillage in the mangroves is preferred as the ideal for a
sustainable and productive human-environment relationship. Lastly,
this study also observes that Remote Sensing approach to vegetation
recovery from oil spill impact has much to do with chlorophyll content
of the vegetation than vegetation area coverage. Consequently, the
assessment and modelling of vegetation recovery from oil spill impact
appear to yield a more reliable result when approached from NDVI
values perspective than from vegetal cover area. However, time-lapse
analysis of vegetation area on oil-impacted site could be a supportive
technique depending on the degree of impact.
Conclusion
In conclusion, the study has showed that oil spillage has serious
impact on the health and growth of mangrove vegetation and it
established that GIS technique is eective for mangrove vegetation
recovery from oil spillage impact. Finally, it should be established
that man cannot run away from reality but face the reality if he don’t
want to cut his life short on this planet, therefore, it is of paramount
importance to concentrate on preventing spills but despite the best
eorts of individual organizations, spills will continue to occur and
will aect the local environment. Response to spills should seek to
minimize the severity of the environmental damage and to hasten the
0.0
2.0
4.0
6.0
8.0
10.0
12.0
14.0
16.0
18.0
1986 1991 1996 2001 2006 2011
Land Cover Area (Km2)
Time Lapse
Trend of Land Cover for Unremediated Site (Km2)
Creeks & Rivers
Deep Swamp
Shallow Swamp
Swamp Soil
Stunted Mangrove
Medium Mangrove
Tall Mangrove
0
10
20
30
40
50
60
70
1986 1991 1996 2001 2006 2011
Land Cover Area (%)
Time Lapse
Trend of Land Cover for Unremediated Site (%)
Creeks & Rivers
Deep Swamp
Shallow Swamp
Swamp Soil
Stunted Mangrove
Medium Mangrove
Tall Mangrove
(a)
(b)
Figure 1a,b: Scatter Plots Showing the Trend of Land Cover Area for Non-
remediated Site over 4 Epochs (1986 - 2007).
0.00
2.00
4.00
6.00
8.00
10.00
12.00
14.00
16.00
1986 1991 1996 2001 2006 2011
Land Cover Area (Km2)
Time Lapse
Trend of Land Cover for Remediated Site (Km2)
Creeks &
Rivers
Deep Swamp
Shallow
Swamp
Swamp Soil
Stunted
Mangrove
Medium
Mangrove
0
10
20
30
40
50
60
1986 1991 1996 2001 2006 2011
Land Cover Area (%)
Time Lapse
Trend of Land Cover for Remediated Site (%)
Creeks & Rivers
Deep Swamp
Shallow Swamp
Swamp Soil
Stunted
Mangrove
Medium
Mangrove
(a)
(b)
Figure 2a,b: Scatter plots showing the trend of landcover area for remediated
over 4 epochs (1986 – 2007).
Citation: Orimoogunje OOI , Ajibola-James O (2013) Mangrove Ecosystem Recovery and Restoration from Oil Spill in the Niger Delta: The GIS Perspective.
Geoinfor Geostat: An Overview S1.
Page 5 of 5
Special Issue 1 • 017
doi:http://dx.doi.org/10.4172/2327-4581.S1-017
recovery of any damaged ecosystem; and the response should always
seek to complement and make use of natural forces to the fullest
extent practicable.
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1Department of Geography, Obafemi Awolowo University, Ile-Ife, Nigeria
2Geo Inheritance Limited, Port Harcourt, Nigeria
... The Niger Delta suffers extensive environmental degradation due to oil extraction, characterized by frequent oil spills, gas flaring, and inadequate regulatory oversight. These activities have led to the pollution of air, soil, and water, resulting in the destruction of mangrove forests and significant loss of biodiversity [15]. Nwankwoala and Nwaogu [5] highlight that oil spills are a primary environmental challenge in the region, with over 1,000 oil production wells and 47,000 km of pipelines contributing to numerous incidents. ...
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This paper examines the environmental impacts of oil extraction in Nigeria's Niger Delta through the lens of Political-Industrial Ecology (PIE). The Niger Delta, known for its rich biodiversity and substantial oil reserves, has experienced severe ecological degradation due to decades of oil exploitation. The environmental challenges include frequent oil spills, gas flaring, and habitat destruction, all of which threaten the livelihoods of local communities and disrupt the delicate balance of the ecosystem. By applying the PIE perspective and analyzing existing literature, government reports, and environmental assessments, this paper aims to clarify the systemic power dynamics between state and corporate interests that prioritize economic profit over environmental protection. This study explores the interconnectedness of political, economic, and environmental factors contributing to the ongoing crisis in the region. It emphasizes the need for a thorough evaluation of the forces that drive environmental degradation and offers insights into potential policy reforms aimed at achieving sustainable development in resource-rich areas like the Niger Delta.
... With over 1,000 oil production wells and 47,000km of oil and gas pipelines (Ngobiri et al., 2007), the Niger Delta grapples with serious environmental issues stemming from oil spill incidents. The region, plagued by frequent oil leaks from various oil facilities, has witnessed adverse effects such as compromised air quality, soil pollution, destruction of mangrove swamps and farmlands, contamination of drinking water sources, and fishing creeks (Orgi, 2001;Twumasi & Merem, 2016;Orimoogunje & Ajibola, 2013). These spills have inflicted substantial economic losses on local inhabitants, many of whom rely on fishing and subsistence farming for their livelihoods. ...
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Oil spillage poses a persistent challenge in Nigeria most especially in oil-rich Niger Delta region, necessitating effective monitoring and mitigation measures. This study provides an overview of oil spill monitoring in Nigeria, emphasizing the pivotal role of remote sensing technology. Leveraging data from the NOSDRA Oil Spill Monitoring website, spanning 2016 to 2020, variations in spill occurrences among oil companies are analyzed. In 2016, a total of 42,741.25 barrels were spilled across 689 incidents, with NPDC emerging as the top spillage contributor. Similarly, 2017 witnessed 35,076.62 barrels spilled across 604 incidents, with NPDC and SPDC maintaining dominance. The trend continued in 2018, with SPDC recording the highest volume of spills among the top six contributing companies. However, in 2019, spillage increased, led by SPDC, followed closely by Heritage Energy Operational Services Limited and Aiteo. Conversely, 2020 saw a decrease in spillage, albeit SPDC retained its lead. These findings underscore the critical need for enhanced monitoring and regulatory enforcement to mitigate the environmental and socio-economic impacts of oil spills in Nigeria. However, proactive measures are needed to strengthen regulatory oversight, improve spill response capabilities, and promote transparency and accountability within the petroleum industry.
... Rhizophoreceae with prop (exposed supporting root) and Avicinniaceae with pneumatophores. Native mangrove plays key part in many fish, invertebrate, crustaceans and mollusk species life cycles; mangrove offer organisms a breeding ground (Orimoogunje and Ajibola-James, 2013). Recently, World Wildlife Fund for Nature (WWF) (2020) reported that mangrove forests are extremely productive ecosystem that provides numerous good and services both to the marine environment and people. ...
... The information on mangrove dynamics serves as a basis for deciding whether or not human interference in the form of management or restoration is appropriate (Dahdouh Guebas et al. 2004). Response to oil spills should seek to minimize the severity of the environmental damage and to hasten the recovery of any damaged ecosystem; and should always seek to complement and make use of natural forces to the fullest extent possible ( Orimoogunje and Ajibola-James 2013). ...
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... For example, Anifowose et al. [24] has focused attention on spills caused by pipeline attacks in the Niger Delta, and connected these incidents to the socio-economic situation in spill incidents areas. Orimoogunje and Ajibola-James [6] has estimated the recovery progress of affected mangroves by spilled oil in the Niger Delta using satellite images. Adamu et al. [25], has analyzed the spectral reflectance of contaminated Oil Spill Influence... mangrove and swamp vegetation areas, then compared between vegetation spectra of polluted and non-polluted sites on Landsat images. ...
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