radiolaria - Marum

Radiolaria 14 Bibliography - 1991
117, Arabian Sea. In: Proceedings of the Ocean Drilling
Program, Scientific Results. (Prell, W.J., Nitsuma, N. et al.,
Eds.), vol. 117. College Station, TX (Ocean Drilling
Program), pp. 127-145.
During the late early Miocene to early middle Miocene, the Owen
Ridge was uplifted to a sufficient height as to be above the realm of
turbidite deposition. Monsoonal-induced upwelling appears to have
been initiated during the Miocene. On the Oman Margin, the effect of
upwelling on the microplankton was established by the middle
Miocene. However, the effects of upwelling on the Owen Ridge region
were not realized until later, in the early late Miocene. A transition in
the upwelling regime took place between the Pliocene and
Pleistocene. While the Miocene and Pliocene sediments are
dominated by the siliceous component, the Pleistocene sediments
seem to be dominated by the calcareous component.
Spero, H.J. & Angel, D.L. 1991. Planktonic
sarcodines: microhabitat for oceanic dinoflagellates. J.
Phyc., 27/2, 187-195.
Two morphologically distinct species of free-swimming
dinoflagellates belonging to the genus Gyrodinium utilize the spine
and rhizopodial environments of planktonic foraminifera and colonial
radiolaria as microhabitats. Up to 84% of the sarcodines examined
in a given population were associated with these dinoflagellates at
densities up to 20,000 cells per sarcodine in some radiolarian
colonies. Both dinofagellate species possess chloroplasts, indicating
they are capable of autotrophy. 14 C-labelling experiments with the
radiolarian-associated dinofagellate demonstrate that it can take up
inorganic carbon under both light and dark conditions.
Ultrastructural evidence suggests the foraminiferal dinoflagellate
may be capable of phagotrophy. Hence, these algae should be
considered mixotrophs. An unusual cytoplasmic extension used for
attachment and possibly feeding occurs in the foraminiferalassociated
Gyrodinium and is documented with electron microscopy.
Ultrastructural examination suggests this organelle may be
hydrostatically controlled and may be an extension of the sac
pusule.
Swanberg, N.R. & Caron, D.A. 1991. Patterns of
sarcodine feeding in epipelagic oceanic plankton. J.
Plankton Res., 13/2, 287-312.
The range of in situ prey composition was determined in marine
planktonic acantharia, foraminifera and radiolaria collected by
divers, and quantitatively compared with the prey available, as
determined by surface plankton hauls on cruises in the Florida
Current, Gulf Stream and Sargasso Sea. A relatively large percentage
of the sarcodines (60% of acantharia, 48% of foraminifera and 46%
of radiolaria) had no detectable prey. Of those which had fed on
identifiable prey, there was considerable overlap between sarcodine
species in the types of prey captured. Nevertheless, some
partitioning of food resources was evident. Foraminifera consumed
greater numbers of diatoms and copepods than other prey types,
radiolaria consumed more tintinnids and mollusc larvae and
acantharia consumed mostly tintinnids. Copepods and their nauplii
dominated the biomass consumed for all three groups, though
mollusc larvae were significant for both acantharia and radiolaria.
The results of parameteric univariate statistical analyses carried
out on each major predator group and multivariate analysis on a
species-by-species basis confirmed that there was evidence for
some partitioning of prey resources among the major sarcodine
predators. The partitioning appeared to follow primarily
morphological rather than taxonomic criteria, however, and may have
been at least partially a mechanical effect.
Takahashi, K. 1991a. Radiolaria: Flux, Ecology, and
Taxonomy in the Pacific and Atlantic. In: Ocean Biocoenosis
Series. (Honjo, S., Eds.), vol. 3. Woods Hole Oceanographic
Institution, Woods Hole, Massachusetts. pp. 303.
Radiolarians settling through the oceanic water column were
recovered from three stations (western tropical Atlantic, Station E;
central tropical Pacific, Station P1 ; and Panama Basin, Station PB)
using PARFLUX sediment traps in moored arrays at several depths.
The taxonomic diversity of the radiolarian assemblages in the
sediment traps was very high. A total of 420 taxa (including 23 new
taxa) were found at the three stations; of these 208 taxa were
found at Station E. The polycystine radiolarians generally reach the
sea floor with little change in abundance or species composition,
although slight skeletal dissolution occurs during their descent
through the water column. The phaeodarian radiolarians, on the other
hand, are largely dissolved within the water column; only a few
species reach the sea-floor and these dissolve rapidly at the
sediment-water interface. Most radiolarian skeletons sink as
individuals through deep water columns without being incorporated
into large biogenic aggregates. Because significant numbers of
nassellarian and phaeodarian species are deep-water dwelling forms,
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the diversity of radiolarians increases with increasing depth in the
mesopelagic zone.
The vertical flow of the total radiolarians arriving at the trap
depths (in x10 3 individuals/m 2 /day) ranged from 16-24 at Station
E, 0.6-17 at Station P1 , and 29-53 at Station PB. On the average
25% and 69% of the total radiolarian flux is transported by
Spumellaria and Nassellaria, respectively, while 5% is carried by
Phaeodaria. The supply of radiolarian silica (mg SiO2 /m 2 /day) to
each trap depth ranged from 2.5-4.0 at Station E, 0.9-3.2 at Station
P l , and 5.7-10.4 at Station PB. The Radiolaria appear to be a
significantly large portion of the SiO2 flux in the > 63 µm size
fraction and thus play an important role in the silica cycle. When the
radiolarian fluxes at the three stations are compared with Holocene
radiolarian accumulation rates in the same areas it became apparent
that several percent or less of the fluxes are preserved in the
sediment in all cases and the rest must be dissolved on the seafloor.
Takahashi, K. 1991b. Mineral flux and biogeochemical
cycles of marine planktonic Protozoa - session summary. In:
Protozoa and their role in marine Processes. (Reid, P.C.,
Turley, C.M. & Burkill, P.H., Eds.), NATO ASI Conference
Series, Series IV Marine Sciences vol. G25. Springer-Verlag,
Berlin/Heidelberg. pp. 347-359.
Since the first NAT0-ASI Workshop on the Ecology of Marine
Planktonic Protozoa was held in Villefranch-sur-mer in 1981, a
marked advance has been made in the study of shell-bearing marine
planktonic protozoa. In particular, vertical flux measurements using
sediment traps (e.g. Deuser et al. 1981, Takahashi and Honjo 1981,
Reid 1982) have contributed to the understanding of marine
ecosystems, and the material balance, and seasonal, interannual,
and spatial distribution of plankton (e.g. Thunell et al. 1983, Be et al.
1985, Smetacek 1985, Pisias et al. 1986, Takahashi 1986, 1987a
b c, Thunell and Honjo 1987, Leventer and Dunbar 1987, Gersonde
and Wefer 1987, Sancetta and Calver 1988.
Fluxes of biogenically precipitated minerals in the oceans,
largely represented by biogenic silica and calcium carbonate, are
important in global ecosystems. Both of the above minerals are
produced in large quantities in marine environments and are partially
entered into the geologic record. It should be noted that oceanic
upper layer biological productivity has changed with time in the past:
for example, significantly different productivity levels from those of
the present day occurred in parts of the world oceans during the
maximum extent of the last glacial age (Sundquist and Broecker
1985). Environmental shifts will likely cause changes not only in
productivity but also in the preservation of sedimenting biogenic
minerals to the sea-floor (Andersen and Malahoff 1977). Between
production and preservation there is some remineralization of
material into the water. The degree of remineralization will cause
changes in productivity in a feed back manner.
Takeuchi, M., Saito, M. & Takizawa, F. 1991.
Radiolarian fossils obtained from conglomerate of the Tetori
Group in the upper reaches of the Kurobegawa River, and its
geologic significance. J. geol. Soc. Japan, 97/5, 345-356.
(in Japanese)
The Tetori Group in the upper reaches of the Kurobegawa River
is divided into three subgroups, the Middle to Late Jurassic Kuzuryu
Subgroup; the late Late Jurassic (?) to early Early Cretaceous
Itoshiro Subgroup, and the late Early Cretaceous Akaiwa Subgroup.
The Tetori Group consists largely of conglomerate and sandstone
with minor mudstone. Late Carboniferous to Middle Permian
radiolarians and late Middle Permian to Late Permian radiolarians
were obtained from the lower conglomerate member. Late Middle
Permian to early Late Permian, late Middle Triassic, and Jurassic
radiolarian fossils were obtained from the uppermost conglomerate
member. The influx of clastic materials from the accretionary
complex suggests that a part of the accretionary complex was
already uplifted and eroded in the late Neocomian.
Thein, M., Ogawa, Y. & Akiyama, T. 1991. Finding
of Cretaceous radiolarians from the block of sheared
olistostrome in the southern part of the Shimanto Belt near
the Ashizumi Cape, Kochi prefecture. J. geol. Soc. Japan,
97/8, 667-669.
The Paleogene succession of the southern part of the Shimanto
Belt in the Hata Peninsula, Kochi Prefecture, is composed of two
formations, namely the Kurusuno Formation (Katto & Mitsui, 1976)
and the Shimizu Formation (Katto, 1960). The two are fault bounded,
whereas the Shimizu Formation is unconformably overlain by the
Lower Miocene Misaki Group (Kimura, 1985). Matsuo (1980)
reported plant fossils having the range from Oligocene to Middle
Miocene in age near Tosashimizu City. Kimura (1985) also found
molluscan fossils on the footpath from Iburi Village leading to