Change in coccolith size and morphology due to response to temperature and salinity in coccolithophore <i>Emiliania huxleyi</i> (Haptophyta) isolated from the Bering and Chukchi seas
Strains of the coccolithophore <i>Emiliania huxleyi</i> (Haptophyta) collected from the subarctic North Pacific and Arctic oceans in 2010 were established as clone cultures and have been maintained in the laboratory at 15 °C and 32 ‰ salinity. To study the physiological responses of cocc...
Main Authors: | , , , , |
---|---|
Format: | Article |
Language: | English |
Published: |
Copernicus Publications
2016-05-01
|
Series: | Biogeosciences |
Online Access: | http://www.biogeosciences.net/13/2743/2016/bg-13-2743-2016.pdf |
id |
doaj-305ff05d8a734d0aa4ec23f16f7c1226 |
---|---|
record_format |
Article |
spelling |
doaj-305ff05d8a734d0aa4ec23f16f7c12262020-11-25T01:57:10ZengCopernicus PublicationsBiogeosciences1726-41701726-41892016-05-011392743275510.5194/bg-13-2743-2016Change in coccolith size and morphology due to response to temperature and salinity in coccolithophore <i>Emiliania huxleyi</i> (Haptophyta) isolated from the Bering and Chukchi seasK. Saruwatari0M. Satoh1N. Harada2I. Suzuki3Y. Shiraiwa4Faculty of Life and Environmental Sciences, University of Tsukuba, Tsukuba, 305-8572, JapanFaculty of Life and Environmental Sciences, University of Tsukuba, Tsukuba, 305-8572, JapanResearch Institute for Global Change, Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Yokosuka, 237-0061, JapanFaculty of Life and Environmental Sciences, University of Tsukuba, Tsukuba, 305-8572, JapanFaculty of Life and Environmental Sciences, University of Tsukuba, Tsukuba, 305-8572, JapanStrains of the coccolithophore <i>Emiliania huxleyi</i> (Haptophyta) collected from the subarctic North Pacific and Arctic oceans in 2010 were established as clone cultures and have been maintained in the laboratory at 15 °C and 32 ‰ salinity. To study the physiological responses of coccolith formation to changes in temperature and salinity, growth experiments and morphometric investigations were performed on two strains, namely MR57N isolated from the northern Bering Sea and MR70N at the Chukchi Sea. This is the first report of a detailed morphometric and morphological investigation of Arctic Ocean coccolithophore strains. The specific growth rates at the logarithmic growth phases in both strains markedly increased as temperature was elevated from 5 to 20 °C, although coccolith productivity (estimated as the percentage of calcified cells) was similar at 10–20 % at all temperatures. On the other hand, the specific growth rate of MR70N was affected less by changes in salinity in the range 26–35 ‰, but the proportion of calcified cells decreased at high and low salinities. According to scanning electron microscopy (SEM) observations, coccolith morphotypes can be categorized into Type B/C on the basis of their biometrical parameters. The central area elements of coccoliths varied from thin lath type to well-calcified lath type when temperature was increased or salinity was decreased, and coccolith size decreased simultaneously. Coccolithophore cell size also decreased with increasing temperature, although the variation in cell size was slightly greater at the lower salinity level. This indicates that subarctic and arctic coccolithophore strains can survive in a wide range of seawater temperatures and at lower salinities with change in their morphology. Because all coccolith biometric parameters followed the scaling law, the decrease in coccolith size was caused simply by the reduced calcification. Taken together, our results suggest that calcification productivity may be used to predict future oceanic environmental conditions in the polar regions.http://www.biogeosciences.net/13/2743/2016/bg-13-2743-2016.pdf |
collection |
DOAJ |
language |
English |
format |
Article |
sources |
DOAJ |
author |
K. Saruwatari M. Satoh N. Harada I. Suzuki Y. Shiraiwa |
spellingShingle |
K. Saruwatari M. Satoh N. Harada I. Suzuki Y. Shiraiwa Change in coccolith size and morphology due to response to temperature and salinity in coccolithophore <i>Emiliania huxleyi</i> (Haptophyta) isolated from the Bering and Chukchi seas Biogeosciences |
author_facet |
K. Saruwatari M. Satoh N. Harada I. Suzuki Y. Shiraiwa |
author_sort |
K. Saruwatari |
title |
Change in coccolith size and morphology due to response to temperature and salinity in coccolithophore <i>Emiliania huxleyi</i> (Haptophyta) isolated from the Bering and Chukchi seas |
title_short |
Change in coccolith size and morphology due to response to temperature and salinity in coccolithophore <i>Emiliania huxleyi</i> (Haptophyta) isolated from the Bering and Chukchi seas |
title_full |
Change in coccolith size and morphology due to response to temperature and salinity in coccolithophore <i>Emiliania huxleyi</i> (Haptophyta) isolated from the Bering and Chukchi seas |
title_fullStr |
Change in coccolith size and morphology due to response to temperature and salinity in coccolithophore <i>Emiliania huxleyi</i> (Haptophyta) isolated from the Bering and Chukchi seas |
title_full_unstemmed |
Change in coccolith size and morphology due to response to temperature and salinity in coccolithophore <i>Emiliania huxleyi</i> (Haptophyta) isolated from the Bering and Chukchi seas |
title_sort |
change in coccolith size and morphology due to response to temperature and salinity in coccolithophore <i>emiliania huxleyi</i> (haptophyta) isolated from the bering and chukchi seas |
publisher |
Copernicus Publications |
series |
Biogeosciences |
issn |
1726-4170 1726-4189 |
publishDate |
2016-05-01 |
description |
Strains of the coccolithophore <i>Emiliania huxleyi</i> (Haptophyta) collected from the subarctic
North Pacific and Arctic oceans in 2010 were established as clone cultures
and have been maintained in the laboratory at 15 °C and
32 ‰ salinity. To study the physiological responses of
coccolith formation to changes in temperature and salinity, growth
experiments and morphometric investigations were performed on two strains,
namely MR57N isolated from the northern Bering Sea and MR70N at the Chukchi
Sea. This is the first report of a detailed morphometric and morphological
investigation of Arctic Ocean coccolithophore strains. The specific growth
rates at the logarithmic growth phases in both strains markedly increased as
temperature was elevated from 5 to 20 °C, although
coccolith productivity (estimated as the percentage of calcified cells) was
similar at 10–20 % at all temperatures. On the other hand, the specific
growth rate of MR70N was affected less by changes in salinity in the range
26–35 ‰, but the proportion of calcified cells
decreased at high and low salinities. According to scanning electron
microscopy (SEM) observations, coccolith morphotypes can be categorized into
Type B/C on the basis of their biometrical parameters. The central area
elements of coccoliths varied from thin lath type to well-calcified lath
type when temperature was increased or salinity was decreased, and coccolith
size decreased simultaneously. Coccolithophore cell size also decreased with
increasing temperature, although the variation in cell size was slightly
greater at the lower salinity level. This indicates that subarctic and
arctic coccolithophore strains can survive in a wide range of seawater
temperatures and at lower salinities with change in their morphology.
Because all coccolith biometric parameters followed the scaling law, the
decrease in coccolith size was caused simply by the reduced calcification.
Taken together, our results suggest that calcification productivity may be
used to predict future oceanic environmental conditions in the polar
regions. |
url |
http://www.biogeosciences.net/13/2743/2016/bg-13-2743-2016.pdf |
work_keys_str_mv |
AT ksaruwatari changeincoccolithsizeandmorphologyduetoresponsetotemperatureandsalinityincoccolithophoreiemilianiahuxleyiihaptophytaisolatedfromtheberingandchukchiseas AT msatoh changeincoccolithsizeandmorphologyduetoresponsetotemperatureandsalinityincoccolithophoreiemilianiahuxleyiihaptophytaisolatedfromtheberingandchukchiseas AT nharada changeincoccolithsizeandmorphologyduetoresponsetotemperatureandsalinityincoccolithophoreiemilianiahuxleyiihaptophytaisolatedfromtheberingandchukchiseas AT isuzuki changeincoccolithsizeandmorphologyduetoresponsetotemperatureandsalinityincoccolithophoreiemilianiahuxleyiihaptophytaisolatedfromtheberingandchukchiseas AT yshiraiwa changeincoccolithsizeandmorphologyduetoresponsetotemperatureandsalinityincoccolithophoreiemilianiahuxleyiihaptophytaisolatedfromtheberingandchukchiseas |
_version_ |
1724976015117123584 |