Editing Lake Titicaca (section)

==Overview==
[[File:Alpaca y la isla Challeca.jpg|left|thumb|A view of Lake Titicaca and Chelleca island in the background. [[Alpaca|Alpacas]] are a common sight along the shores of the lake.]]
The lake is located at the northern end of the [[endorheic]] [[Altiplano]] basin high in the [[Andes]] on the border of Peru and Bolivia. The western part of the lake lies within the [[Puno Region]] of Peru, and the eastern side is located in the Bolivian [[La Paz Department (Bolivia)|La Paz Department]].

The lake consists of two nearly separate subbasins connected by the [[Strait of Tiquina]], which is {{cvt|800|m|ft|-1}} across at the narrowest point. The larger subbasin, ''Lago Grande'' (also called ''Lago Chucuito''), has a mean depth of {{cvt|135|m|ft|0}} and a maximum depth of {{cvt|284|m|ft|0}}. The smaller subbasin, [[Wiñaymarka]] (also called ''Lago Pequeño'', "little lake"), has an average depth of {{cvt|9|m|ft|0}} and a maximum depth of {{cvt|40|m|ft|0}}.<ref name="Dejoux">Dejoux, C. and A. Iltis (editors) (1992). ''Lake Titicaca: A Synthesis of Limnological Knowledge''. 68. Kluwer Academic Publishers, Boston.</ref> The overall average depth of the lake is {{cvt|107|m|ft|0}}.<ref name="ilec">{{cite web |url=http://www.ilec.or.jp/database/sam/dsam04.html |title=Data Summary: Lago Titicaca (Lake Titicaca) |publisher=International Lake Environment Committee Foundation – ILEC |access-date=2009-01-03 |url-status=dead |archive-url=https://web.archive.org/web/20110723165816/http://www.ilec.or.jp/database/sam/dsam04.html |archive-date=2011-07-23}}</ref>
[[File:Copacabana, Bolivia at sunset.jpg|left|thumb|A view of Lake Titicaca taken from the town of [[Copacabana, Bolivia|Copacabana]], Bolivia]]
Five major river systems feed into Lake Titicaca.<ref>Roche, M. A., J. Bourges, J. Cortes and R. Mattos (1992). Climatology and Hydrology of the Lake Titicaca Basin. In ''Lake Titicaca: A Synthesis of Limnological Knowledge'', edited by C. Dejoux and A. Iltis, pp. 63–88. Monographiae Biologicae. vol. 68, H. J. Dumont and M. J. A. Werger, general editor. Kluwer Academic Publishers, Boston.</ref> In order of their relative flow volumes, these are Ramis, Coata, Ilave, Huancané, and Suchez.<ref name=strontium/> More than 20 other smaller streams empty into Titicaca. The lake has 41 islands, some of which are densely populated.

Having only a single season of free circulation, the lake is [[monomictic]],<ref name=cross>Cross, S. L., P. A. Baker, G. O. Seltzer, S. C. Fritz and R. B. Dunbar (2001). Late Quaternary Climate and Hydrology of Tropical South America Inferred from an Isotopic and Chemical Model of Lake Titicaca, Bolivia and Peru. ''Quaternary Research'' 56(1):1–9.</ref><ref>Mourguiart, P., T. Corrége, D. Wirrmann, J. Argollo, M. E. Montenegro, M. Pourchet and P. Carbonel (1998). Holocene Palaeohydrology of Lake Titicaca Estimated from an Ostracod-Based Transfer Function. ''Palaeogeography, Palaeoclimatology, Palaeoecology'' 143:51–72.</ref> and water passes through Lago Huiñaimarca and flows out the single outlet at the [[Desaguadero River (Bolivia and Peru)|Río Desaguadero]],<ref>Baucom, P. C. and C. A. Rigsby 1999 Climate and Lake Level History of the Northern Altiplano, Bolivia, as Recorded in Holocene Sediments of the Río Desaguadero. ''Journal of Sedimentary Research'' 69(3):597–611.</ref> which then flows south through Bolivia to [[Lake Poopó]]. This only accounts for about 10% of the lake's [[water balance]]. [[Evapotranspiration]], caused by strong winds and intense sunlight at high altitude, balances the remaining 90% of the water loss. It is nearly a closed lake.<ref name=strontium/><ref name="Dejoux" /><ref>Talbi, A., A. Coudrain, P. Ribstein and B. Pouyaud (1999). Computation of the Rainfall of Lake Titicaca Catchment During the Holocene. ''Géosciences de Surface'' 329:197–203.</ref>
[[File:Vista de Puno y el Titicaca, Perú, 2015-08-01, DD 63.JPG|left|thumb|The city of [[Puno]] in Peru, the largest urban settlement on the lake]]
Since 2000, Lake Titicaca has experienced constantly receding water levels. Between April and November 2009 alone, the water level dropped by {{cvt|81|cm|in|0}}, reaching the lowest level since 1949. This drop is caused by shortened rainy seasons and the melting of glaciers feeding the tributaries of the lake.<ref>Carlos Valdez: [http://news.smh.com.au/breaking-news-world/lake-titicaca-at-dangerously-low-level-20091113-idgf.html ''Lake Titicaca at dangerously low level''] {{Webarchive |url=https://web.archive.org/web/20150205215942/http://news.smh.com.au/breaking-news-world/lake-titicaca-at-dangerously-low-level-20091113-idgf.html |date=2015-02-05 }} – website of the Sydney Morning Herald (accessed 2009-11-28)</ref><ref>[https://www.youtube.com/watch?v=KCLNKU5N3mY ''Lake Titicaca evaporating away (video)''] {{Webarchive |url=https://web.archive.org/web/20220128120434/https://www.youtube.com/watch?v=KCLNKU5N3mY |date=2022-01-28 }} – report by [[Al Jazeera Arabic|al Jazeera]] (accessed 2009-11-28)</ref> [[Water pollution in Peru|Water pollution]] is also an increasing concern because cities in the Titicaca [[Drainage basin|watershed]] grow, sometimes outpacing solid waste and sewage treatment infrastructure.<ref>{{cite news |last=Shahriari |first=Sara |title=Pollution threatens South America's Lake Titicaca |url=http://www.csmonitor.com/World/Americas/2012/0330/Pollution-threatens-South-America-s-Lake-Titicaca |access-date=26 May 2012 |newspaper=The Christian Science Monitor |date=30 March 2012 |archive-date=12 November 2020 |archive-url=https://web.archive.org/web/20201112024616/https://www.csmonitor.com/World/Americas/2012/0330/Pollution-threatens-South-America-s-Lake-Titicaca |url-status=live }}</ref> According to the [[Global Nature Fund]] (GNF), Titicaca's biodiversity is threatened by water pollution and the [[introduced species|introduction]] of new species by humans.<ref>{{cite web |url=http://www.globalnature.org/35193/Living-Lakes/America/Lake-Titicaca/resindex.aspx |title=GNF – Lake Titicaca |first=Almut |last=Weis |website=www.globalnature.org |access-date=2015-05-19 |archive-date=2020-11-27 |archive-url=https://web.archive.org/web/20201127164848/https://www.globalnature.org/35193/Living-Lakes/America/Lake-Titicaca/resindex.aspx |url-status=live }}</ref> A 2011 United Nations report found alarming concentrations of cadmium, arsenic, and lead in various parts of the lake.<ref>{{Cite web |title=The Devastating Pollution of Lake Titicaca in Peru: Causes and Consequences |url=https://www.ecohubmap.com/hot-spot/pollution-of-lake-titicaca-peru/3wt1klfu2hodv |access-date=2023-12-18 |website=www.ecohubmap.com}}</ref><ref>{{Cite journal |last=Monroy |first=Mario |last2=Maceda-Veiga |first2=Alberto |last3=de Sostoa |first3=Adolfo |date=2014-07-15 |title=Metal concentration in water, sediment and four fish species from Lake Titicaca reveals a large-scale environmental concern |url=https://pubmed.ncbi.nlm.nih.gov/24784748/ |journal=The Science of the Total Environment |volume=487 |pages=233–244 |doi=10.1016/j.scitotenv.2014.03.134 |issn=1879-1026 |pmid=24784748}}</ref> In 2012, the GNF nominated the lake "Threatened Lake of the Year".<ref>{{cite web |url=https://www.globalnature.org/35755/Living-Lakes/Threatened-Lake-2016/Threatened-Lake-2012/resindex.aspx |title=Threatened Lake of the Year 2012 |publisher=GNF |date=22 March 2012 |access-date=2 March 2017 |archive-date=28 November 2020 |archive-url=https://web.archive.org/web/20201128135332/https://www.globalnature.org/35755/Living-Lakes/Threatened-Lake-2016/Threatened-Lake-2012/resindex.aspx |url-status=live }}</ref>