Micro-phytoplankton variability at the equatorial Pacific (140W̊) during the JGOFS EQPAC Time Series Studies 1992 /

(SST = 25'C) were associated with increased abundance (range

Bibliographic Details
Main Author: Iriarte, Jose Luis
Format: Thesis eBook
Language:English
Published: [Place of publication not identified] : [publisher not identified] ; 1994.
Subjects:
Online Access:Link to OAKTrust copy
Description
Summary:(SST = 25'C) were associated with increased abundance (range
= 2xIO2 to 12xlo3 cells liter-1), and richness in rnicro-
140'W, during two JGOFS EqPac Time Series Studies, in order
3000 cells liter- 1) and carbon biomass (< 1 lAg C liter-1)
abundance and species richness found in the equatorial
an instability wave during March-April and October 1992,
and coccolithophorids, were examined. During the abnormal
and dinoffagenates were restricted to the surface and to the
assemblage between March-April and October 1992, to find the
average, micro-phytoplanlaon carbon ranged from 0.5 to 4.0 Ag
by a colonial pennate diatom P. delicatissima. On the
by low numbers of diatoms and coccolithophorids. The pennate
C liter-1, where the diatom group consistently comprised the
characterized the micro-phytoplankton structure, accompanied
complex were important groups contributing to the total
conditions in March-April 1992 exhibited lower micro-
diatom, Pseudonitzschia delicatissima, and the thecate
dinoflageflate, Oxytoxum variabile, were the most abundant
during Time Series I. The presence of an El Niflo event and
mainly due to the passage of a instability wave through the
major part of the microphytoplanlaon autotrophic biomass in
Micro-phytoplankton (>20 gm cell size) was sampled in the
micro-phytoplankton carbon biomass. At the equator, diatoms
October 1992. Also in contrast to the spring, in the autumn
of three major taxonomic classes: diatoms, dinoflagellates
organisms observed during the March-April 1992 Time Series
Pacific at 140'W during the study periods.
phytoplankton species assemblage, which was again dominated
phytoplankton species richness and abundance compared with
phytoplankton structure. Cell abundance and carbon biomass
relate any changes in the environmental factors to micro-
respectively, may explain most of the variability in
silicified species of the 77zalassionemal77wlassiothrix spp.
species, as well as chains of P. delicatissima, and heavily
study site. During this period, the coldest temperatures
study. The microphytoplankton assemblage during El Niflo
the micro-phytoplankton assemblage showed large variability,
the upper 60 m. Large centric diatoms, such as Rhizosolenia
to determine the changes in the micro-phytoplanlcton
upper 200 m of the water column at the Pacific equator,
upper 60 m, respectively, during both Time Series cruises,
vertical distribution of micro-phytoplankton taxa, and to
warmth of El Nifto 1992 (S ST = 28 - 29'C), low abundance (<
while coccolithophorid cells where concentrated at 90 m
Item Description:"Major subject: Oceanography".
In title, numerals are used.
Vita.
Physical Description:viii, 74 leaves : illustrations, maps ; 28 cm.
Also available online.
Bibliography:Includes bibliographical references.