The fate of copepod populations in the Paranapanema River (São Paulo, Brazil), downstream from the Jurumirim dam
The longitudinal changes in the structure of copepod populations were examined during the dry and rainy seasons in a 42 km stretch of the Paranapanema River downstream from the dam of the Jurumirim Reservoir. Samples were taken in the "lacustrine" zone of the reservoir near the dam, and al...
| Main Authors: | , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Instituto de Tecnologia do Paraná (Tecpar)
2002-01-01
|
| Series: | Brazilian Archives of Biology and Technology |
| Subjects: | |
| Online Access: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132002000600012 |
| _version_ | 1828840987910209536 |
|---|---|
| author | Mitsuka Patricia Maria Henry Raoul |
| author_facet | Mitsuka Patricia Maria Henry Raoul |
| author_sort | Mitsuka Patricia Maria |
| collection | DOAJ |
| description | The longitudinal changes in the structure of copepod populations were examined during the dry and rainy seasons in a 42 km stretch of the Paranapanema River downstream from the dam of the Jurumirim Reservoir. Samples were taken in the "lacustrine" zone of the reservoir near the dam, and also at 12 stations distributed in the middle and the lateral regions of the channel of the Paranapanema River downstream from the dam. The following species of Cyclopoida were found at the sites: Thermocyclops decipiens, Thermocyclops minutus, Paracyclops sp., Tropocyclops sp and Mesocyclops sp., and of Calanoida: Argyrodiaptomus furcatus, Notodiaptomus iheringi and Notodiaptomus conifer. In the reservoir sampling station, the copepod abundance during the dry and rainy seasons corresponded to 41 and 51% of the total zooplankton, respectively. This difference could be related to the rainfall and water level variations, and especially to the influence of variables such as water temperature, dissolved oxygen and chlorophyll-a contents. No significant differences in organism numbers were recorded among samples of zooplankton taken in the middle and near-bank parts of the river. In relation to longitudinal variation in the Paranapanema River stretch, a significant decrease in density and disappearance of some species were recorded 11km downstream of the dam during the dry season. At the stations 32km from the dam, a drastic reduction in copepod abundance was observed in the rainy season. These observations could be linked not only to environmental changes from lentic to lotic conditions, but also to the combination of certain factors such as current velocity, water outflow of the reservoir, and rainfall. |
| first_indexed | 2024-12-12T19:53:25Z |
| format | Article |
| id | doaj.art-229c38fbe2154618b4fa6b026525184e |
| institution | Directory Open Access Journal |
| issn | 1516-8913 1678-4324 |
| language | English |
| last_indexed | 2024-12-12T19:53:25Z |
| publishDate | 2002-01-01 |
| publisher | Instituto de Tecnologia do Paraná (Tecpar) |
| record_format | Article |
| series | Brazilian Archives of Biology and Technology |
| spelling | doaj.art-229c38fbe2154618b4fa6b026525184e2022-12-22T00:13:56ZengInstituto de Tecnologia do Paraná (Tecpar)Brazilian Archives of Biology and Technology1516-89131678-43242002-01-01454479490The fate of copepod populations in the Paranapanema River (São Paulo, Brazil), downstream from the Jurumirim damMitsuka Patricia MariaHenry RaoulThe longitudinal changes in the structure of copepod populations were examined during the dry and rainy seasons in a 42 km stretch of the Paranapanema River downstream from the dam of the Jurumirim Reservoir. Samples were taken in the "lacustrine" zone of the reservoir near the dam, and also at 12 stations distributed in the middle and the lateral regions of the channel of the Paranapanema River downstream from the dam. The following species of Cyclopoida were found at the sites: Thermocyclops decipiens, Thermocyclops minutus, Paracyclops sp., Tropocyclops sp and Mesocyclops sp., and of Calanoida: Argyrodiaptomus furcatus, Notodiaptomus iheringi and Notodiaptomus conifer. In the reservoir sampling station, the copepod abundance during the dry and rainy seasons corresponded to 41 and 51% of the total zooplankton, respectively. This difference could be related to the rainfall and water level variations, and especially to the influence of variables such as water temperature, dissolved oxygen and chlorophyll-a contents. No significant differences in organism numbers were recorded among samples of zooplankton taken in the middle and near-bank parts of the river. In relation to longitudinal variation in the Paranapanema River stretch, a significant decrease in density and disappearance of some species were recorded 11km downstream of the dam during the dry season. At the stations 32km from the dam, a drastic reduction in copepod abundance was observed in the rainy season. These observations could be linked not only to environmental changes from lentic to lotic conditions, but also to the combination of certain factors such as current velocity, water outflow of the reservoir, and rainfall.http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132002000600012Downstreamreservoircopepodabundance |
| spellingShingle | Mitsuka Patricia Maria Henry Raoul The fate of copepod populations in the Paranapanema River (São Paulo, Brazil), downstream from the Jurumirim dam Brazilian Archives of Biology and Technology Downstream reservoir copepod abundance |
| title | The fate of copepod populations in the Paranapanema River (São Paulo, Brazil), downstream from the Jurumirim dam |
| title_full | The fate of copepod populations in the Paranapanema River (São Paulo, Brazil), downstream from the Jurumirim dam |
| title_fullStr | The fate of copepod populations in the Paranapanema River (São Paulo, Brazil), downstream from the Jurumirim dam |
| title_full_unstemmed | The fate of copepod populations in the Paranapanema River (São Paulo, Brazil), downstream from the Jurumirim dam |
| title_short | The fate of copepod populations in the Paranapanema River (São Paulo, Brazil), downstream from the Jurumirim dam |
| title_sort | fate of copepod populations in the paranapanema river sao paulo brazil downstream from the jurumirim dam |
| topic | Downstream reservoir copepod abundance |
| url | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132002000600012 |
| work_keys_str_mv | AT mitsukapatriciamaria thefateofcopepodpopulationsintheparanapanemariversaopaulobrazildownstreamfromthejurumirimdam AT henryraoul thefateofcopepodpopulationsintheparanapanemariversaopaulobrazildownstreamfromthejurumirimdam AT mitsukapatriciamaria fateofcopepodpopulationsintheparanapanemariversaopaulobrazildownstreamfromthejurumirimdam AT henryraoul fateofcopepodpopulationsintheparanapanemariversaopaulobrazildownstreamfromthejurumirimdam |