Role of heterotrophic dinoflagellates in the fate of diatoms released from fast ice in coastal water of Lützow-Holm Bay, East Antarctica

Ichinomiya, Mutsuo; Nakamachi, Miwa; Honda, Masaki; Fukuchi, Mitsuo; Taniguchi, Atsushi

doi:10.3354/meps07966

Cited by 3 publications

(2 citation statements)

References 50 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Since thecate dinoflagellates, potential predators of diatoms (Sherr and Sherr 2007) did not substantially increase in the control bottles, it is likely that the naked ciliates grazed those diatoms in the control bottle. Active ingestion of diatoms by naked ciliates was often observed when diatoms are abundant (Montagnes 1996; Aberle et al 2007; Ichinomiya et al 2009), although ciliates were traditionally considered as major grazers of microalgae, preying mainly upon nanoplankton‐size fractions. We are not certain why Thalassiosira spp.…”

Section: Discussionmentioning

confidence: 99%

Higher ingestion rates and importance of ciliates in the diet of a large, subarctic copepod revealed by larger volume incubations

Takahashi

Ichinomiya

Okazaki

et al. 2023

Limnology & Oceanography

View full text Add to dashboard Cite

Despite ecological importance, the feeding ecology of the large calanoid copepod, Neocalanus cristatus is little known, as its ingestion rate under experimental conditions consistently falls short of its metabolic demand. The conventional incubation bottle size (~ 2 liters) used in previous studies may have affected its feeding behavior. Here, we examined the effect of bottle size (2.4 vs. 13liters) and copepod density on the feeding of N. cristatus Stage C5. Under similar copepod density (0.4 ind. L−1) ingestion rates decreased significantly for tests conducted in small bottles and thus, small bottles inhibited copepod feeding. In experiments with large bottles, ingestion rates were highest in the single‐individual treatments (1 ind. 13 L−1), decreasing exponentially to < 1% of the maximum ingestion rate with increasing copepod densities (up to 20 ind. 13 L−1). Considerable food limitation occurred in the higher copepod density treatments with lower initial prey allocation per individual. Moreover, in the single‐individual treatments, clearance rates on naked ciliates (11–20 L ind.−1 d−1) were remarkably higher than in multiple‐individual treatments. Grazer–grazer interaction, thus, interfered with copepod feeding on microzooplankton in multiple‐individual treatments. The ingestion rate in the single‐individual treatments (62–102 μgC ind.−1 d−1) exceeded the daily metabolic requirement; feeding rates noted in previous studies were, thus, underestimations, affected by bottle size and copepod mutual interference. Efficient feeding by N. cristatus on naked ciliates emphasizes the importance of the ciliate‐copepod link in the grazing food chain in the subarctic Pacific.

show abstract

Section: Discussionmentioning

confidence: 99%

Higher ingestion rates and importance of ciliates in the diet of a large, subarctic copepod revealed by larger volume incubations

Takahashi

Ichinomiya

Okazaki

et al. 2023

Limnology & Oceanography

View full text Add to dashboard Cite

show abstract

“…However, filamentous algae and chain-forming diatoms observed beneath ice cover on the late-winter cruise in 2007 suggest that, in years with ice, diatoms may contribute organic matter to secondary producers. Ichinomiya et al (2009) estimated that approximately 50% of diatoms released from ice are exploited by both pelagic and benthic grazers, while only 3% of diatom loss is attributable to sinking. Thus, if there was rapid and selective grazing on diatoms by abundant copepods and microzooplankton, a significant fraction of ice-attached diatoms might be consumed by the pelagic grazers.…”

Section: Role Of Diatomsmentioning

confidence: 99%

Community metabolism and energy transfer in the Chesapeake Bay estuarine turbidity maximum

Lee¹,

Keller²,

Crump³

et al. 2012

Mar. Ecol. Prog. Ser.

View full text Add to dashboard Cite

In an effort to identify the key mechanisms controlling biological productivity and food web structure in the Chesapeake Bay estuarine turbidity maximum (ETM), we measured plankton community metabolism on a series of surveys in the upper Chesapeake Bay during the winter and spring of 2007 and 2008. Measured quantities included primary production, bacterial production, planktonic community respiration, and algal pigment concentrations. These measurements revealed a classic minimum in photosynthesis in the vicinity of the ETM. Temporal variability in plankton community metabolism, primary production, respiration, and bacterial production were highest in the southern oligohaline region down-estuary of the ETM and appeared to be driven by dynamic bio-physical interactions. Elevated primary production and community respiration in this region were often associated with the presence of mixotrophic dinoflagellates. The dinoflagellate contribution to primary production and respiration appeared to be particularly large as a result of their mixotrophic capabilities, which allow them to obtain energy both autotrophically and heterotrophically. The present study suggests that mixotrophic dinoflagellates play a key role in the pelagic food web in the oligohaline region of Chesapeake Bay, supplying most of the labile organic matter during late winter and spring and also providing a vector for transferring microbial production to mesozooplankton. KEY WORDS: Estuarine turbidity maximum · Plankton community metabolism · Mixotrophic dinoflagellate · Estuarine food web · Chesapeake Bay Resale or republication not permitted without written consent of the publisherMar Ecol Prog Ser 449: 65-82, 2012 66 aquatic sources. Estimating the quantity and quality of this organic matter is difficult due to the diverse origins and complex biogeochemical reactions that occur between dissolved and particulate organic matter and living organisms (Simon et al. 2002). In lakes, stable isotope analysis of organic carbon indicates that a greater fraction of heterotrophic metabolism is fueled by terrestrial organic matter than by autochthonous primary producers when environmental conditions limit autotrophic production (Carpenter et al. 2005, Pace et al. 2007). In Chesapeake Bay, primary production and chlorophyll a (chl a) concentrations are lowest in the oligohaline area (Smith & Kemp 1995), presumably due to light limitation (Fisher et al. 1999), suggesting that, as in lakes, terrestrial organic matter plays an important role in heterotrophic production.Understanding the relative importance of auto chthonous algal production compared to allochthonous input in the ETM is particularly important because this region is an area of high larval recruitment for many fish species including striped bass Morone saxatilis and white perch M. americana (North & Houde 2006). Mesozooplankton such as the calanoid copepods Eurytemora affinis and Acartia tonsa and the freshwater cladoceran Bosmina longirostris are also very abundant (Roman et al. 2001). E...

show abstract

References

2012

The Biology and Ecology of Tintinnid Ciliates

View full text Add to dashboard Cite

Role of heterotrophic dinoflagellates in the fate of diatoms released from fast ice in coastal water of Lützow-Holm Bay, East Antarctica

Abstract: , indicating almost positive growth of HD in the water column. This demonstrates that HD are major consumers of the diatoms released from the fast ice, forming a dominant trophic link between diatoms and HD in the Antarctic under-ice ecosystem.

Cited by 3 publications

References 50 publications

Higher ingestion rates and importance of ciliates in the diet of a large, subarctic copepod revealed by larger volume incubations

Higher ingestion rates and importance of ciliates in the diet of a large, subarctic copepod revealed by larger volume incubations

Community metabolism and energy transfer in the Chesapeake Bay estuarine turbidity maximum

References

Contact Info

Product

Resources

About