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Saline lake ecosystems of Mexico
J. Alocera,*,
U.T. Hammerb
aLimnology Laboratory, Environmental
conservation & improvement Project, UIJGSE, Universidad
Nacional Autonoma de Mexico Campus Iztacala, Ay, de los Barrios
s/n, Los Reyes Iztacala, 54090 Tlalnepantla, Estado de Mexico,
Mexico
bDepartment of Biology; University of Saskatchewan,
Saskatoon, Saskatchewan, Canada S7N 5W2
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Abstract
This paper aims
to draw attention to the need to better know' and understand Mexican
saline lakes. It does this by outlining their distribution, abundance
and location and their physical, chemical and biological characteristics.
The influence of climatic factors on saline lakes is discussed.
To sharpen the focus of the general discussion, a few Mexican saline
lakes are discussed in more detail in each of the indicated topics.
Saline lakes are found throughout Mexico, with the greatest number
in the northwest and the least in the southeast, and from sea level
to altitudes above 2000 m. Mexican saline lakes widely fluctuate
morphometrically. The majority are tiny, shallow, and temporal with
small volumes. Some are large or deep, and perennial with large
volumes. Polymixis is common in shallow lakes while deeper ones
are monotmictic. Temperature and dissolved oxygen fluctuate widely.
Alkaline waters are frequent. Mirroring high primary productivity
rates, water is often green and turbid but other colors (blue, sepia,
purple, yellow) and clear water are also found. Most lakes are sodium
chloride or alkali carbonate types. Salts resulting from the combination
of sodium with chloride, carbonates and sulfates are common and,
to a lesser extent, salts of calcium, potassium, magnesium, lithium
and boron are present. Species richness in Mexican saline lakes
decreases as salinity rises. Hyposaline lakes display a more diverse
biota than hypersaline ones. Organisms commonly found in Mexican
saline lakes are: blue-green algae (e.g., Spirulina geitleri,
Phormidium tenue), rotifers (Brachionus spp.), anostracans
(Artemia spp.), copepods (e.g., Diaptotnus, Leptodiaptomus),
corixid bugs (e.g., Corisella, Krizousaconixa, Trichocorixella),
ephydrids (e.g., Ephydra hians), the neotenic salamander
(e.g., Ambystoma app.), atherinids (e.g., Chinortoma
spp.), goodeids (e.g., Goodea spp.), cyprinodontids (e.g.,
Cyprinodon spp.), poecilids (e.g., Gambusia spp.),
and the Caribbean pink flamingo (Phoenicopterus ruber ruber).
© 1999 Elsevier Science Ltd and AEHMS. All rights reserved.
Keywords: Athalassohaline; Plankton;
Nekton; Benthos; Macrophytes; Vertebrates
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