ALGAL PIGMENT FINGERPRINTS: CLUE TO TAXON-SPECIFIC ABUNDANCE,
PRODUCTIVITY AND DEGRADATION OF PHYTOPLANKTON IN SEAS AND
OCEANS
W.W.C. Gieskes
University of Groningen
Department of Marine Biology
PO Box 14
9750 AA Haren (Gn),
The Netherlands
INTRODUCTION
A principal assignment of the Pelagic Ecosystem Research Group established at the
Netherlands Institute for Sea Research in the early seventies was to contribute to the existing
body of knowledge of the primary production of seas and oceans. We soon realised that
incubations of natural phytoplankton to assess 14C incorporation are time-consuming and can
only be performed at a few stations, which should be as representative as possible for the
survey region. The phytoplankton in the North Sea coastal areas that we were to survey
appeared to be distributed very irregularly both in space and in time. Also in the open ocean
patchiness was reported to be the rule rather than the exception (Lorenzen, 1967a). The only
way to arrive at reasonable estimates of primary production in the marine environment is to
establish the relation between photosynthesis and a few parameters determining the growth
potential of algal cells that can be measured quickly and therefore frequently. Chlorophyll a,
the pigment that is central in light capture for photosynthesis, was selected by us as one of
these because reliable methods for its measurement have been presented by Holm-Hansen et
al. (1965) and Lorenzen (1 967b) just a few years before we started our work in the Dutch part
of the North Sea. The great seasonal and regional variability in phytoplankton biomass in
these waters is expressed in the chlorophyll distribution (Fig. 1), assuming that chlorophyll
is an indicator of biomass. The other major parameter that is important for aquatic primary
production, underwater light availability, was simply determined from surface irradiance and
Secchi disc observations, the attenuation coefficient k being calculated from k = flS, with f
ranging from 1.4 in turbid coastal waters, 1.7 in offshore neritic waters, and 2.2 in
oligotrophic ocean waters - a variability due to reasons unknown to us at that time.
NATO ASI Series, Vol. G 27
Particle Analysis in Oceanography
Edited by S. Demers
© Springer-Verlag Berlin Heidelberg 1991
PRODUCTIVITY AND DEGRADATION OF PHYTOPLANKTON IN SEAS AND
OCEANS
W.W.C. Gieskes
University of Groningen
Department of Marine Biology
PO Box 14
9750 AA Haren (Gn),
The Netherlands
INTRODUCTION
A principal assignment of the Pelagic Ecosystem Research Group established at the
Netherlands Institute for Sea Research in the early seventies was to contribute to the existing
body of knowledge of the primary production of seas and oceans. We soon realised that
incubations of natural phytoplankton to assess 14C incorporation are time-consuming and can
only be performed at a few stations, which should be as representative as possible for the
survey region. The phytoplankton in the North Sea coastal areas that we were to survey
appeared to be distributed very irregularly both in space and in time. Also in the open ocean
patchiness was reported to be the rule rather than the exception (Lorenzen, 1967a). The only
way to arrive at reasonable estimates of primary production in the marine environment is to
establish the relation between photosynthesis and a few parameters determining the growth
potential of algal cells that can be measured quickly and therefore frequently. Chlorophyll a,
the pigment that is central in light capture for photosynthesis, was selected by us as one of
these because reliable methods for its measurement have been presented by Holm-Hansen et
al. (1965) and Lorenzen (1 967b) just a few years before we started our work in the Dutch part
of the North Sea. The great seasonal and regional variability in phytoplankton biomass in
these waters is expressed in the chlorophyll distribution (Fig. 1), assuming that chlorophyll
is an indicator of biomass. The other major parameter that is important for aquatic primary
production, underwater light availability, was simply determined from surface irradiance and
Secchi disc observations, the attenuation coefficient k being calculated from k = flS, with f
ranging from 1.4 in turbid coastal waters, 1.7 in offshore neritic waters, and 2.2 in
oligotrophic ocean waters - a variability due to reasons unknown to us at that time.
NATO ASI Series, Vol. G 27
Particle Analysis in Oceanography
Edited by S. Demers
© Springer-Verlag Berlin Heidelberg 1991