ISSN:
1573-8590
Schlagwort(e):
benthic macroinvertebrates
;
crater-lake
;
physico-chemistry
;
shallow lake
;
tropical lake
Quelle:
Springer Online Journal Archives 1860-2000
Thema:
Biologie
,
Geographie
Notizen:
Abstract The effects of multiple stressors on the benthic macroinvertebrate community were monitored in Tecuitlapa Norte, a shallow, perennially-astatic, warm, mesosaline, soda-alkaline lake in Mexico. Physico-chemical and biological variables were determined monthly for one year. Tecuitlapa Norte displayed a clear seasonal environmental pattern (dry and rainy seasons). The benthic macroinvertebrate community consisted of five species: Culicoides occidentalis sonorensis Jorgensen, Ephydra hians Say, Stratiomys sp., Eristalis sp., and Limnophora sp. of which the first two were dominant and the rest scarce. C. occidentalis was the most important species numerically (76 percent of the total), while E. hians dominated the biomass (73 percent of the total). Primarily salinity and secondarily pH appear to be the most important environmental factors controlling dominance of benthic organisms in Tecuitlapa Norte. Seasonal abundance dynamics of the dominant organisms was associated with phases in their reproductive cycles: environmentally-triggered (i.e., temperature rise, water-level descent) pupation and emergence periods. We concluded that whereas physical and chemical factors (i.e., salinity, pH) exerted the primary control on benthic macroinvertebrate community composition in Tecuitlapa Norte, another assembly of variables (e.g., water-level, temperature) influenced species distribution and abundance.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1023/A:1009059028881
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