Nigeria

== Geography ==
{{main|Geography of Nigeria|Geology of Nigeria|Wildlife of Nigeria}}
[[File:Nigeria Topography.png|thumb|Topography of Nigeria]]
Nigeria is located in western Africa on the [[Gulf of Guinea]] and has a total area of {{convert|923768|km2|mi2|0|abbr=on}},<ref>{{cite web |title=Rank Order – Area |url=https://www.cia.gov/library/publications/the-world-factbook/rankorder/2147rank.html |url-status=dead |archive-url=https://web.archive.org/web/20140209041128/https://www.cia.gov/library/publications/the-world-factbook/rankorder/2147rank.html |archive-date=9 February 2014 |access-date=29 May 2011 |work=[[The World Factbook]] |publisher=[[Central Intelligence Agency]]}}</ref> making it the world's [[List of countries and dependencies by area|32nd-largest country]]. Its borders span {{convert|4,047|km|mi}}, and it shares borders with Benin ({{convert|773|km|mi|disp=or|abbr=on}}), Niger ({{convert|1,497|km|mi|disp=or|abbr=on}}), Chad ({{convert|87|km|mi|disp=or|abbr=on}}), and Cameroon (including the separatist [[Ambazonia]]) {{convert|1,690|km|mi|disp=or|abbr=on}}. Its [[coastline]] is at least {{convert|853|km|abbr=on}}.<ref>{{cite web |date=17 May 2011 |title=Africa :: Nigeria |url=https://www.cia.gov/the-world-factbook/countries/nigeria/ |access-date=29 May 2011 |work=[[The World Factbook]] |publisher=[[Central Intelligence Agency]]}} *Note that coastlines, and borders based on rivers or natural features, are fractals, the length of which is imprecise and depends on the measurement convention adopted.</ref> Nigeria lies between latitudes [[4th parallel north|4°]] and [[14th parallel north|14°N]], and longitudes [[2nd meridian east|2°]] and [[15th meridian east|15°E]]. The highest point in Nigeria is [[Chappal Waddi]] at {{convert|2419|m|ft|0|abbr=on}}. The main rivers are the [[Niger River|Niger]] and the [[Benue River|Benue]], which converge and empty into the [[Niger Delta]]. This is one of the world's largest river deltas and the location of a large area of Central African [[mangrove]]s.

Nigeria's most expansive topographical region is that of the valleys of the Niger and Benue river valleys (which merge and form a Y-shape).<ref name="encarta22">{{cite encyclopedia |title=Nigeria |encyclopedia=[[Encarta]] |publisher=[[Microsoft]] |url=http://encarta.msn.com/encyclopedia_761557915/Nigeria.html |access-date=19 July 2007 |archive-url=https://web.archive.org/web/20031111170137/http://encarta.msn.com/encyclopedia_761557915/Nigeria.html |archive-date=11 November 2003 |url-status=dead}}</ref> To the southwest of the Niger is a "rugged" [[Highland (geography)|highland]]. To the southeast of the Benue are hills and mountains, which form the [[Mambilla Plateau]], the highest plateau in Nigeria. This plateau extends through the border with [[Cameroon]], where the [[montane]] land is part of the [[Bamenda Highlands]] of Cameroon.

[[File:Koppen-Geiger Map NGA present.svg|thumb|alt=|Climate map of Nigeria]]

The far south is defined by its [[tropical rainforest climate]], where annual rainfall is {{convert|60|to|80|in|mm|-2|order=flip}} per year.<ref name="gai52">{{cite web |title=Regions Used to Interpret the Complexity of Nigeria |url=http://www.uni.edu/gai/Nigeria/Background/Standard5.html |archive-url=https://web.archive.org/web/20090414075757/http://www.uni.edu/gai/Nigeria/Background/Standard5.html |archive-date=14 April 2009 |access-date=19 July 2007 |work=Geographical Alliance of Iowa |publisher=[[University of Northern Iowa]]}}</ref> In the southeast stands the [[Obudu Plateau]]. [[Coastal plain]]s are found in both the southwest and the southeast.<ref name="encarta22" /> [[Mangrove swamp]]s are found along the coast.<ref name="gai42">{{cite web |title=The Human and Physical Characteristics of Nigeria |url=http://www.uni.edu/gai/Nigeria/Background/Standard4.html |archive-url=https://web.archive.org/web/20100328172528/http://www.uni.edu/gai/Nigeria/Background/Standard4.html |archive-date=28 March 2010 |access-date=13 August 2007 |work=Geographical Alliance of Iowa |publisher=[[University of Northern Iowa]]}}</ref>

The area near the border with Cameroon close to the coast is rich rainforest and part of the [[Cross–Sanaga–Bioko coastal forests|Cross-Sanaga-Bioko coastal forests]] [[ecoregion]], an important centre for [[biodiversity]]. It is a habitat for the [[Drill (animal)|drill primate]], which is found in the wild only in this area and across the border in Cameroon. The areas surrounding [[Calabar]], Cross River State, also in this forest, are believed to contain the world's largest diversity of butterflies. The area of southern Nigeria between the Niger and the [[Cross River (Nigeria)|Cross Rivers]] has lost most of its forest because of development and harvesting by increased population, and has been [[Cross–Niger transition forests|replaced by grassland]].

Everything in between the far south and the far north is [[savanna]]h (insignificant tree cover, with grasses and flowers located between trees). Rainfall is more limited to between {{convert|20|and|60|in|mm|-2|order=flip}} per year.<ref name="gai52" /> The savannah zone's three categories are [[Guinean forest–savanna mosaic|Guinean forest-savanna mosaic]], Sudan savannah, and Sahel savannah. Guinean forest-savanna mosaic is plains of tall grass interrupted by trees. Sudan savannah is similar but with shorter grasses and shorter trees. Sahel savannah consists of patches of grass and sand, found in the northeast.<ref name="gai42" />[[File:Megachad en disappearance of lake chad.jpg|thumb|Shrinking of [[Lake Chad]] in north-eastern Nigeria, with the outline of the [[British Isles]] for size comparison]]

=== Hydrology ===
Nigeria is divided into two main catchment areas - that of Lake Chad and that of the Niger. The Niger catchment area covers about 63% of the country. The main tributary of the Niger is the Benue, whose tributaries extend beyond Cameroon into Cameroon into Chad and the Sharie catchment area. In the Sahel region, rain is less than {{convert|20|in|mm|sigfig=1|order=flip}} per year, and the [[Sahara|Sahara Desert]] is encroaching.<ref name="gai52" /> In the dry northeast corner of the country lies [[Lake Chad]], on a [[Lake Chad Basin Commission|shared water]] boundary [[Boundary delimitation|delimitation]] with Niger, Chad and Cameroon.

The Chad Basin is fed from the north-eastern quarter of Nigeria. The Bauchi Plateau forms the watershed between the Niger/Benue and Komadugu Yobe river systems. The flat plains of north-eastern Nigeria are geographically part of the Chad Basin, where the course of the El Beid River forms the border with Cameroon, from the Mandara Mountains to Lake Chad. The Komadugu Yobe river system gives rise to the internationally important Hadejia-Nguru wetlands and Ox-bow lakes around Lake Nguru in the rainy season.<ref>{{cite journal |last=Gbolagade |first=Lameed |title=Species diversity and richness of wild birds in Dagona Waterfowl Sanctuary, Nigeria |journal=African Journal of Environmental Science and Technology |year=2011 |edition=5 |pages=855–866 |issn=1996-0786}}</ref><ref>{{Cite web |date=2013-10-02 |title=Chad Basin National Park |url=http://cbnp.nigeriaparkservice.org/sectors.php |archive-url=https://web.archive.org/web/20131002082125/http://cbnp.nigeriaparkservice.org/sectors.php |archive-date=2013-10-02 |access-date=2022-10-22}}</ref> Other rivers of the northeast include the Ngadda and the Yedseram, both of which flow through the Sambisa swamps, thus forming a river system. The river system of the northeast is also a major river system.<ref>{{Cite web |date=2016-03-04 |title=TRANSBOUNDARY DIAGNOSTIC ANALYSIS OF THE LAKE CHAD BASIN |url=http://lakechad.iwlearn.org/publications/reports/lake-cha-basin-tda-report-english |archive-url=https://web.archive.org/web/20160304105554/http://lakechad.iwlearn.org/publications/reports/lake-cha-basin-tda-report-english |archive-date=2016-03-04 |access-date=2022-10-22}}</ref> In addition, Nigeria has numerous coastal rivers.

[[File:Lake Chad from Apollo 7.jpg|thumb|Photo of Lake Chad from [[Apollo 7]], 1968]]

Over the last million years, [[Lake Chad]] in the far north-east of Nigeria has dried up several times for a few thousand years and just as often growing to many times its current size. In recent decades its surface area has been reduced considerably, which may also be due to humans taking water from the inlets to irrigate agricultural land.

===Vegetation===
Nigeria is covered by three types of vegetation: forests (where there is significant tree cover), [[savannah]]s (insignificant tree cover, with grasses and flowers located between trees), and [[montane]] land (least common and mainly found in the mountains near the Cameroon border). Both the forest zone and the savannah zone are divided into three parts.<ref name="gai4">{{cite web |title=The Human and Physical Characteristics of Nigeria |url=http://www.uni.edu/gai/Nigeria/Background/Standard4.html |url-status=dead |archive-url=https://web.archive.org/web/20100328172528/http://www.uni.edu/gai/Nigeria/Background/Standard4.html |archive-date=2010-03-28 |access-date=2007-08-13 |work=Geographical Alliance of Iowa |publisher=[[University of Northern Iowa]]}}</ref>

Some of the forest zone's most southerly portion, especially around the Niger River and [[Cross River (Nigeria)|Cross River]] deltas, is [[Central African mangroves|mangrove swamp]]. North of this is fresh water swamp, containing different vegetation from the salt water mangrove swamps, and north of that is rain forest.<ref name="gai4" />

The savannah zone's three categories are divided into [[Guinean forest–savanna mosaic|Guinean forest-savanna mosaic]], made up of plains of tall grass which are interrupted by trees, the most common across the country; Sudan savannah, with short grasses and short trees; and [[Sahel]] savannah patches of grass and sand, found in the northeast.<ref name="gai4" />

[[File:The Mambilla Plateau, Nigeria 01.jpg|thumb|The [[Mambilla Plateau]] in the North-Eastern region of Nigeria]]

=== Environmental issues ===
{{further|Deforestation in Nigeria|Environmental issues in the Niger Delta}}
[[File:Nigerian-deforrestation-b.jpg|alt=Nigerian deforrestation 1981 - 2020|thumb|Deforestation in Nigeria 1981–2020<ref>{{Cite journal |last=Fashae |first=Olutoyin |date=2017 |title=Geospatial Analysis of Changes in Vegetation Cover over Nigeria |url=https://www.researchgate.net/publication/321953126 |journal=Bulletin of Geography |issue=13 |pages=17–27}}</ref>]]
[[Waste management]] including [[sewage treatment]], the linked processes of [[deforestation]] and [[Soil retrogression and degradation|soil degradation]], and [[climate change]] or [[global warming]] are the major environmental problems in Nigeria. Waste management presents problems in a [[megacity]] like Lagos and other major Nigerian cities which are linked with economic development, population growth and the inability of municipal councils to manage the resulting rise in industrial and domestic waste. This waste management problem is also attributable to unsustainable environmental management lifestyles of [[Kubwa, Abuja|Kubwa]] community in the Federal Capital Territory, where there are habits of indiscriminate disposal of waste, dumping of waste along or into the canals, sewerage systems that are channels for water flows, and the like. Haphazard industrial planning, increased urbanisation, poverty and lack of competence of the municipal government are seen as the major reasons for high levels of waste pollution in major cities of the country. Some of the solutions have been disastrous to the environment, resulting in untreated waste being dumped in places where it can pollute waterways and [[Groundwater in Nigeria|groundwater]].<ref>{{cite journal |last1=Ogbonna |first1=D.N. |last2=Ekweozor |first2=I.K.E. |last3=Igwe |first3=F.U. |year=2002 |title=Waste Management: A Tool for Environmental Protection in Nigeria |journal=Ambio: A Journal of the Human Environment |volume=31 |issue=1 |pages=55–57 |doi=10.1639/0044-7447(2002)031[0055:wmatfe]2.0.co;2 |jstor=4315211}}</ref>

In 2005, Nigeria had the highest rate of [[deforestation]] in the world, according to the [[Food and Agriculture Organization]] of the [[United Nations]].<ref>{{cite web |date=17 November 2005 |title=News.mongabay.com |url=http://news.mongabay.com/2005/1117-forests.html |access-date=28 July 2014 |publisher=News.mongabay.com}}</ref> That year, 12.2%, the equivalent of 11,089,000 hectares, had been forested in the country. Between 1990 and 2000, Nigeria lost an average of 409,700 hectares of forest every year equal to an average annual deforestation rate of 2.4%. Between 1990 and 2005, in total Nigeria lost 35.7% of its [[forest cover]] or around 6,145,000 hectares.<ref>{{cite web |date=1 January 2010 |title=Rainforest analysis at Mongabay.com |url=http://rainforests.mongabay.com/deforestation/2000/Nigeria.htm |access-date=28 July 2014 |publisher=Rainforests.mongabay.com}}</ref> Nigeria had a 2019 [[Forest Landscape Integrity Index]] mean score of 6.2/10, ranking it 82nd globally out of 172 countries.<ref name="FLII-Supplementary">{{cite journal |last1=Grantham |first1=H. S. |last2=Duncan |first2=A. |last3=Evans |first3=T. D. |last4=Jones |first4=K. R. |last5=Beyer |first5=H. L. |last6=Schuster |first6=R. |last7=Walston |first7=J. |last8=Ray |first8=J. C. |last9=Robinson |first9=J. G. |last10=Callow |first10=M. |last11=Clements |first11=T. |last12=Costa |first12=H. M. |last13=DeGemmis |first13=A. |last14=Elsen |first14=P. R. |last15=Ervin |first15=J. |display-authors=1 |year=2020 |title=Anthropogenic modification of forests means only 40% of remaining forests have high ecosystem integrity - Supplementary Material |journal=Nature Communications |volume=11 |issue=1 |page=5978 |doi=10.1038/s41467-020-19493-3 |issn=2041-1723 |pmc=7723057 |pmid=33293507 |last16=Franco |first16=P. |last17=Goldman |first17=E. |last18=Goetz |first18=S. |last19=Hansen |first19=A. |last20=Hofsvang |first20=E. |last21=Jantz |first21=P. |last22=Jupiter |first22=S. |last23=Kang |first23=A. |last24=Langhammer |first24=P. |last25=Laurance |first25=W. F. |last26=Lieberman |first26=S. |last27=Linkie |first27=M. |last28=Malhi |first28=Y. |last29=Maxwell |first29=S. |last30=Mendez |first30=M. |last31=Mittermeier |first31=R. |last32=Murray |first32=N. J. |last33=Possingham |first33=H. |last34=Radachowsky |first34=J. |last35=Saatchi |first35=S. |last36=Samper |first36=C. |last37=Silverman |first37=J. |last38=Shapiro |first38=A. |last39=Strassburg |first39=B. |last40=Stevens |first40=T. |last41=Stokes |first41=E. |last42=Taylor |first42=R. |last43=Tear |first43=T. |last44=Tizard |first44=R. |last45=Venter |first45=O. |last46=Visconti |first46=P. |last47=Wang |first47=S. |last48=Watson |first48=J. E. M.|bibcode=2020NatCo..11.5978G }}</ref>

In the year 2010, thousands of people were inadvertently [[Zamfara State lead poisoning outbreak|exposed to lead-containing soil]] from informal [[gold mining]] within the northern state of Zamfara. While estimates vary, it is thought that upwards of 400 children died of acute [[lead poisoning]], making this perhaps the largest lead poisoning fatality outbreak ever encountered.<ref>{{Cite journal |last1=Bashir |first1=Muhammed |last2=Umar-Tsafe |first2=Nasir |last3=Getso |first3=Kabiru |last4=Kaita |first4=Ibrahim M. |last5=Nasidi |first5=Abdulsalami |last6=Sani-Gwarzo |first6=Nasir |last7=Nguku |first7=Patrick |last8=Davis |first8=Lora |last9=Brown |first9=Mary Jean |date=18 April 2014 |title=Assessment of blood lead levels among children aged ≤ 5 years—Zamfara State, Nigeria, June–July 2012 |journal=MMWR. Morbidity and Mortality Weekly Report |volume=63 |issue=15 |pages=325–327 |issn=1545-861X |pmc=5779393 |pmid=24739340}}</ref>

Nigeria's Delta region is one of the most polluted regions in the world due to serious [[oil spill]]s and other environmental problems caused by its oil industry.<ref>{{cite web |last=Donatus |first=Peter |date=2016-10-15 |title=Shell's Nigeria ecocide is creating a refugee crisis |url=https://www.greenleft.org.au/content/shell%E2%80%99s-nigeria-ecocide-creating-refugee-crisis,%20https://www.greenleft.org.au/content/shell%E2%80%99s-nigeria-ecocide-creating-refugee-crisis |access-date=2023-07-06 |website=greenleft.org.au}}{{dead link|date=July 2023 |bot=InternetArchiveBot |fix-attempted=yes}}</ref><ref>{{cite web |last= |date=2017-08-07 |title=UNEP Ogoniland Oil Assessment Reveals Extent of Environmental Contamination and Threats to Human Health |url=http://www.unep.org/news-and-stories/story/unep-ogoniland-oil-assessment-reveals-extent-environmental-contamination-and |access-date=2023-07-06 |website=UNEP}}</ref> The heavy contamination of the air, ground and water with toxic pollutants is often used as an example of [[ecocide]].<ref>{{cite web |date=2021-04-07 |title='Ecocide' movement pushes for a new international crime: Environmental destruction |url=https://www.nbcnews.com/news/world/ecocide-movement-pushes-new-international-crime-environmental-destruction-n1263142 |access-date=2023-07-06 |publisher=NBC News}}</ref><ref>{{cite web |title=Fighting ecocide in Nigeria |url=https://theecologist.org/2014/feb/05/fighting-ecocide-nigeria |access-date=2023-07-06 |website=theecologist.org|date=5 February 2014 }}</ref><ref>{{cite web |title=UNPO: Ogoni: An Ecocide in the Making? |url=https://unpo.org/article/19131 |access-date=2023-07-06 |website=unpo.org}}</ref><ref>{{cite news |date=2011-08-22 |title=How an ecocide law could prevent another Nigerian oil disaster |language=en-GB |work=The Guardian |url=https://www.theguardian.com/environment/2011/aug/22/ecocide-law-nigerian-oil-disaster |access-date=2023-07-06 |issn=0261-3077}}</ref><ref>{{Cite web |date=2023-06-02 |title=Spotlighting oil majors' 'ecocide' of Niger Delta: Q&A with Michael J. Watts |url=https://news.mongabay.com/2023/06/spotlighting-oil-majors-ecocide-of-niger-delta-qa-with-michael-j-watts/ |access-date=2023-07-06 |website=Mongabay Environmental News |language=en-US}}</ref> In additional to the environmental damage it has caused [[Conflict in the Niger Delta|conflict in the Delta region]].

Illegal oil refineries, in which local operators convert stolen crude oil into petrol and diesel, are considered particularly "dirty, dangerous and lucrative".<ref>{{cite news |date=2022-04-26 |title=Nigeria's illegal oil refineries: Dirty, dangerous, lucrative |language=en-GB |publisher=BBC News |url=https://www.bbc.com/news/world-africa-61216157 |access-date=2022-10-10}}</ref> Safety and environmental aspects are usually ignored. Refining petroleum also inevitably produces heavy oil, which is "cracked" into lighter fuel components in regular plants at great technical expense. Illegal refineries do not have these technical possibilities and "dispose" of the heavy oil where it accumulates. The lighter components of crude oil ([[methane]] to [[butane]], [[isobutane]]) create a certain risk of explosion, which often leads to disasters at illegal plants.<ref>{{cite web |last1=Okereke |first1=Chukwumerije |last2=Emodi |first2=Nnaemeka Vincent |last3=Diemuodeke |first3=Ogheneruona E. |title=Three things that can go wrong at an illegal oil refinery in Nigeria |url=http://theconversation.com/three-things-that-can-go-wrong-at-an-illegal-oil-refinery-in-nigeria-182459 |access-date=2022-10-10 |website=The Conversation |date=9 May 2022}}</ref> In 2022, Nigeria suffered 125 deaths from explosions at local, illegal refineries.<ref>{{cite web |last=Onukwue |first=Alexander |date=2022-04-25 |title=Nigeria's illegal oil refineries keep killing people |url=https://qz.com/africa/2158492/nigerias-illegal-oil-refineries-keep-killing-people/ |access-date=2022-10-10 |website=Quartz}}</ref>