Seasonal changes of the zooplankton from streams and tropical swamps of the eastern Chaco (Argentina)

The zooplankton of 20 streams and 4 tropical swamps located in an area locally called "Eastern Chaco" (comprised by the Pilcomayo river to 28°S and the Paraguay and Paraná rivers to 60°W) was studied from May to October, 1984, during high and low water periods. Three series of quantitative...

Descripción completa

Guardado en:
Detalles Bibliográficos
Autores principales: Martinez, Clara C., Frutos, Santa M.
Formato: Artículo revista
Lenguaje:Español
Publicado: Centro de Ecología Aplicada del Litoral (Consejo Nacional de Investigaciones Científicas y Técnicas - Universidad Nacional de Nordeste) 2023
Acceso en línea:https://revistas.unne.edu.ar/index.php/sub/article/view/7174
Aporte de:
id I48-R154-article-7174
record_format ojs
institution Universidad Nacional del Nordeste
institution_str I-48
repository_str R-154
container_title_str Revistas UNNE - Universidad Nacional del Noroeste (UNNE)
language Español
format Artículo revista
author Martinez, Clara C.
Frutos, Santa M.
spellingShingle Martinez, Clara C.
Frutos, Santa M.
Seasonal changes of the zooplankton from streams and tropical swamps of the eastern Chaco (Argentina)
author_facet Martinez, Clara C.
Frutos, Santa M.
author_sort Martinez, Clara C.
title Seasonal changes of the zooplankton from streams and tropical swamps of the eastern Chaco (Argentina)
title_short Seasonal changes of the zooplankton from streams and tropical swamps of the eastern Chaco (Argentina)
title_full Seasonal changes of the zooplankton from streams and tropical swamps of the eastern Chaco (Argentina)
title_fullStr Seasonal changes of the zooplankton from streams and tropical swamps of the eastern Chaco (Argentina)
title_full_unstemmed Seasonal changes of the zooplankton from streams and tropical swamps of the eastern Chaco (Argentina)
title_sort seasonal changes of the zooplankton from streams and tropical swamps of the eastern chaco (argentina)
description The zooplankton of 20 streams and 4 tropical swamps located in an area locally called "Eastern Chaco" (comprised by the Pilcomayo river to 28°S and the Paraguay and Paraná rivers to 60°W) was studied from May to October, 1984, during high and low water periods. Three series of quantitative samples (53 in total; 100 liters each) were collected just below the surface at 24 stations placed along a transect paralell to the National Highway 11, with a 10 liters vessel and a 53 μm-mesh sieve. Some of the streams which were subject to wide environmental fluctuations showed clear changes in the density and dominance conditions of the zooplankton in relation to the hydrologic regime and the conductivity of the water. During the high water period, characterized by conductivity values between 90 and 420 μS.cm-1, collections from open water locales vielded low densities (10 to 100 individuals.liter-1) and invariably contained littoral and periphytic taxa which were swept into the streams from other waterbodies (swamps, small pools). Maxima of both conductivity (11 OOOnS.cm -1) and zooplankton numbers (1 500 individuals.liter-1) occurred during the dry season, with dominance of rotifers adapted to high salinity conditions (Brachionus plicatilis, B. angularis, Synchaeta sp., etc.). Other streams presented low values of conductivity (below 500μS.cm-1) and a well developed aquatic vegetation during both high and low water periods; the zooplankton was here dominated by Bdelloidea, Polyarthra sp. and Filinia sp., the halophilous species being absent. The microcrustacean fauna of the streams was almost invariably characterized by large numbers of species and low densities, Ceriodaphnia sp. and Copepoda nauplii being the only organisms of some numerical importance. In the swamps, both truly planktonic species (Polyarthra sp. (vulgaris-dolichoptera group), Keratella lenzi, K. serrulata, Filinia terminalis, F. longiseta, Diaphanosoma sp.) and a large number of adventitious (pseudo planktonic) forms were recorded; this assemblage and the relatively high density of organisms during the dry season (up to 300 individuals.liter-1) contrast noticeably with the few available records from adjacent areas. 
publisher Centro de Ecología Aplicada del Litoral (Consejo Nacional de Investigaciones Científicas y Técnicas - Universidad Nacional de Nordeste)
publishDate 2023
url https://revistas.unne.edu.ar/index.php/sub/article/view/7174
work_keys_str_mv AT martinezclarac seasonalchangesofthezooplanktonfromstreamsandtropicalswampsoftheeasternchacoargentina
AT frutossantam seasonalchangesofthezooplanktonfromstreamsandtropicalswampsoftheeasternchacoargentina
AT martinezclarac fluctuaciontemporaldelzooplanctonenarroyosyesterosdelchacoorientalargentina
AT frutossantam fluctuaciontemporaldelzooplanctonenarroyosyesterosdelchacoorientalargentina
first_indexed 2024-08-21T22:39:03Z
last_indexed 2024-08-21T22:39:03Z
_version_ 1808038566409797632
spelling I48-R154-article-71742023-12-06T15:26:09Z Seasonal changes of the zooplankton from streams and tropical swamps of the eastern Chaco (Argentina) Fluctuación temporal del zooplancton en arroyos y esteros del Chaco Oriental (Argentina) Martinez, Clara C. Frutos, Santa M. The zooplankton of 20 streams and 4 tropical swamps located in an area locally called "Eastern Chaco" (comprised by the Pilcomayo river to 28°S and the Paraguay and Paraná rivers to 60°W) was studied from May to October, 1984, during high and low water periods. Three series of quantitative samples (53 in total; 100 liters each) were collected just below the surface at 24 stations placed along a transect paralell to the National Highway 11, with a 10 liters vessel and a 53 μm-mesh sieve. Some of the streams which were subject to wide environmental fluctuations showed clear changes in the density and dominance conditions of the zooplankton in relation to the hydrologic regime and the conductivity of the water. During the high water period, characterized by conductivity values between 90 and 420 μS.cm-1, collections from open water locales vielded low densities (10 to 100 individuals.liter-1) and invariably contained littoral and periphytic taxa which were swept into the streams from other waterbodies (swamps, small pools). Maxima of both conductivity (11 OOOnS.cm -1) and zooplankton numbers (1 500 individuals.liter-1) occurred during the dry season, with dominance of rotifers adapted to high salinity conditions (Brachionus plicatilis, B. angularis, Synchaeta sp., etc.). Other streams presented low values of conductivity (below 500μS.cm-1) and a well developed aquatic vegetation during both high and low water periods; the zooplankton was here dominated by Bdelloidea, Polyarthra sp. and Filinia sp., the halophilous species being absent. The microcrustacean fauna of the streams was almost invariably characterized by large numbers of species and low densities, Ceriodaphnia sp. and Copepoda nauplii being the only organisms of some numerical importance. In the swamps, both truly planktonic species (Polyarthra sp. (vulgaris-dolichoptera group), Keratella lenzi, K. serrulata, Filinia terminalis, F. longiseta, Diaphanosoma sp.) and a large number of adventitious (pseudo planktonic) forms were recorded; this assemblage and the relatively high density of organisms during the dry season (up to 300 individuals.liter-1) contrast noticeably with the few available records from adjacent areas.  The zooplankton of 20 streams and 4 tropical swamps located in an area locally called "Eastern Chaco" (comprised by the Pilcomayo river to 28°S and the Paraguay and Paraná rivers to 60°W) was studied from May to October, 1984, during high and low water periods. Three series of quantitative samples (53 in total; 100 liters each) were collected just below the surface at 24 stations placed along a transect paralell to the National Highway 11, with a 10 liters vessel and a 53 μm-mesh sieve. Some of the streams which were subject to wide environmental fluctuations showed clear changes in the density and dominance conditions of the zooplankton in relation to the hydrologic regime and the conductivity of the water. During the high water period, characterized by conductivity values between 90 and 420 μS.cm-1, collections from open water locales vielded low densities (10 to 100 individuals.liter-1) and invariably contained littoral and periphytic taxa which were swept into the streams from other waterbodies (swamps, small pools). Maxima of both conductivity (11 OOOnS.cm -1) and zooplankton numbers (1 500 individuals.liter-1) occurred during the dry season, with dominance of rotifers adapted to high salinity conditions (Brachionus plicatilis, B. angularis, Synchaeta sp., etc.). Other streams presented low values of conductivity (below 500μS.cm-1) and a well developed aquatic vegetation during both high and low water periods; the zooplankton was here dominated by Bdelloidea, Polyarthra sp. and Filinia sp., the halophilous species being absent. The microcrustacean fauna of the streams was almost invariably characterized by large numbers of species and low densities, Ceriodaphnia sp. and Copepoda nauplii being the only organisms of some numerical importance. In the swamps, both truly planktonic species (Polyarthra sp. (vulgaris-dolichoptera group), Keratella lenzi, K. serrulata, Filinia terminalis, F. longiseta, Diaphanosoma sp.) and a large number of adventitious (pseudo planktonic) forms were recorded; this assemblage and the relatively high density of organisms during the dry season (up to 300 individuals.liter-1) contrast noticeably with the few available records from adjacent areas.  Centro de Ecología Aplicada del Litoral (Consejo Nacional de Investigaciones Científicas y Técnicas - Universidad Nacional de Nordeste) 2023-12-06 info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion Artículo revisado por pares application/pdf https://revistas.unne.edu.ar/index.php/sub/article/view/7174 Ambiente Subtropical; Núm. 1 (1986): AMBIENTES ANEGABLES DEL CHACO ORIENTAL Primera parte; 112-133 spa https://revistas.unne.edu.ar/index.php/sub/article/view/7174/6608