|
Vol. 43 No. 2, 2004
Temporal
Variability and Production of the Planktonic Copepod Community in the
Cananéia Lagoon Estuarine System, São Paulo, Brazil
Koichi Ara
Instituto
Oceanográfico, Universidade de São Paulo, Pra a do Oceanográfico 191,
Cidade Universitária, Butantã, São Paulo - SP05508-900, Brazil
Koichi Ara (2004) Diel
and seasonal variations in the abundance, biomass, and production rate
of the planktonic copepod community were investigated in the Cananéia
Lagoon estuarine system, a mangrove-surrounded estuary located near the
southern border of São Paulo State, Brazil. On each sampling date,
zooplankton samples were collected using a 150-µm-mesh plankton net at
intervals of 4 h over multiple 24-h periods from February 1995 to
January 1996. Copepods accounted for 68.1%~97.7% (with an annual mean
of 84.8%) of the total zooplankton abundance. The copepod community
consisted of 37 species; the dominant species were Oithona hebes, O.
oswaldocruzi, Acartia lilljeborgi, A. tonsa, Pseudodiaptomus acutus,
Parvocalanus crassirostris, Euterpina acutifrons and Temora turbinata.
Copepod abundance, biomass, and production rates showed remarkable
seasonal variations, being highest in January. Annual mean abundance,
biomass, and estimated production rate, using the Hirst-Lampitt model,
of copepodites and adults were 3.33 x 104 ± 1.76 x 104 individuals m-3,
19.757 ± 9.776 mg C m-3 and 5.249 ± 3.055 mg C m-3 d-1 (mean ± SD),
respectively. The daily mean P/B ratio was 0.20~0.38 d-1. During the
study period, the copepod community consisted mainly of the small-sized
component: copepods with a total body length less than 1000 µm
accounted for 75.1%~99.9% (with an annual mean of 93.1%) of the total
copepod abundance. The median individual weight was 0.46~0.95 µg C
(with an annual median of 0.63 µg C), and copepods weighing less than 1
µg C dominated the biomass and production rate, constituting 28.7%~68%
(with an annual mean of 52.1%) and 43.3%~79.7% (with an annual mean of
66.1%) of the copepod community biomass and production rate,
respectively.
Key words: Copepod community, Production, Cananéia Lagoon estuarine system, Brazil.
*Correspondence:
Present address: Department of Marine Science and Resources, College of
Bioresource Sciences, Nihon University, Kameino 1866, Fujisawa,
Kanagawa 252-8510, Japan. Tel/Fax: 81-466-84-3686. E-mail:
arakoich@brs.nihon-u.ac.jp
|
