Short Communication

Primary production in the Benguela ecosystem, 1999–2002

  • R Barlow
  • T Lamont
  • B Mitchell-Innes
  • M Lucas
  • S Thomalla

Abstract

Phytoplankton production was investigated throughout the whole Benguela ecosystem in winter 1999 and in summer 2002 during two four-week research cruises from Cape Town, South Africa, through Namibian waters to Namibe in southern Angola. Primary production ranged from 0.14–2.26 g C m–2 d–1 during June–July 1999 and from 0.39–8.83 g C m–2 d–1 during February–March 2002. Mean productivity values indicated that the Benguela ecosystem was twice as  productive in summer than in winter. In 1999, most of the productivity occurred within a temperature range of 13.5–18 °C, whereas in 2002 elevated production was associated with temperatures of 14–22 °C. The relationship between primary production and chlorophyll a was good for winter 1999 but poor for summer 2002, suggesting that predicting primary production from chlorophyll a is not straightforward for the Benguela ecosystem.

Keywords: chlorophyll a; primary production; temperature

African Journal of Marine Science 2009, 31(1): 97–101

Author Biographies

R Barlow
Marine and Coastal Management, Department of Environmental Affairs and Tourism, Private Bag X2, Rogge Bay 8012, South Africa
T Lamont
Marine and Coastal Management, Department of Environmental Affairs and Tourism, Private Bag X2, Rogge Bay 8012, South Africa
B Mitchell-Innes
Marine and Coastal Management, Department of Environmental Affairs and Tourism, Private Bag X2, Rogge Bay 8012, South Africa
M Lucas
Department of Zoology, University of Cape Town, Rondebosch 7701, South Africa
S Thomalla
Department of Oceanography, University of Cape Town, Rondebosch 7701, South Africa
Section
Articles

eISSN: 1814-2338