chiton Acanthopleura hirtosa. Journal of Structural Biology,
167, 55–61.
Sawlowlicz, Z., 1993. Pyrite framboids and their development:
a new conceptual mechanism. Geologische Rundschau, 82,
148–156.
Schieber, J., 2002. Sedimentary pyrite: a window into the microbial
past. Geology, 30, 531–534.
Schippers, A., and Jørgensen, B. B., 2002. Biogeochemistry of
pyrite and iron sulfide oxidation in marine sediments.
Geochimica et Cosmochimica Acta, 66(1), 85–92.
Schneiderhohn, H., 1923. Chalkographische Untersuchung des
Mansfelder Kupferschiefers. Neues Jahrbuch für Geologie und
Paläontologie, 47, 1–38.
Semeniuk, V., 1980. Quaternary stratigraphy of the tidal flats King
Sound, WA. Journal of the Royal Society of Western Australia,
63, 65–78.
Semeniuk, V., 2010. A note on calcite precipitates as encrustations
around sea rush roots and as microlaminae in high tidal zones
of western Leschenault Inlet estuary. Journal of the Royal Society of Western Australia, 93, 195–199.
Semeniuk, V., Semeniuk, T. A., and Unno, J., 2000. The
Leschenault Inlet estuary – an overview. Journal of the Royal
Society of Western Australia Special Issue on the Leschenault
Inlet Estuary, 83, 207–228.
Simkiss, K., and Wilbur, K. M., 1989. Biomineralization: Cell Biology and Deposition. London: Academic Press.
Sumper, M., and Kroger, N., 2004. Silica formation in diatoms: the
function of long-chain polyamines and silaffins. Journal of
Materials Chemistry, 14, 2059–2065.
Sunagawa, I., Endo, Y., and Nakai, N., 1971. Hydrothermal synthesis of framboidal pyrite. Society of Mining Geologists of Japan
(Special Issue), 2, 10–14.
Sweeney, R. E., and Kaplan, I. R., 1973. Pyrite framboid formation;
laboratory synthesis and marine sediments. Economic Geology,
68(5), 618–634.
van Beusekom, J. E. E., and de Jonge, V. N., 1997. Transformation
of phosphorus in the Wadden Sea: Apatite formation. Deutsche
Hydrografische Zeitschrift, 49, 297–305.
von der Borch, C. C., Rubin, M., and Skinner, B. J., 1964. Modern
dolomite from South Australia. American Journal of Science,
262, 1116–1118.
von der Borch, C. C., Lock, D., and Schwebel, D., 1975. Groundwater formation of dolomite in the Coorong region of South
Australia. Geology, 3, 283–285.
Warner, G. F., 1977. The Biology of Crabs. London: Elek Science.
Wilkin, R. T., and Barnes, H. L., 1997a. Pyrite formation in an
anoxic estuarine basin. American Journal of Science, 297(6),
620–650.
Wilkin, R. T., and Barnes, H. L., 1997b. Formation processes of
framboidal pyrite. Geochimica et Cosmochimica Acta, 61(2),
323–339.
Wilkin, R. T., Barnes, H. L., and Brantley, S. L., 1996. The size distribution of framboidal pyrite in modern sediments: an indicator
of redox conditions. Geochimica et Cosmochimica Acta, 60(20),
3897–3912.
Wopenka, B., and Pasteris, J. D., 2005. A mineralogical perspective
on the apatite in bone. Materials Science and Engineering C, 25,
131–143.
Cross-references
Biogenous Sediment
Diagenesis
Microbial Degradation
Nitrification
Nutrient Dynamics
Shell Beds
MIXOTROPHIC PLANKTON
Jason E. Adolf
Department of Marine Science, University of Hawaii at
Hilo, Hilo, HI, USA
Definition
Mixotrophic plankton are those that use a combination of
phototrophic and heterotrophic nutrition.
Mixotrophic plankton and our evolving
view of pelagic foodwebs
Traditionally, oceanographers and limnologists categorize plankton as “phytoplankton” and “zooplankton,”
implying functional roles analogous to plants and animals, respectively, in terrestrial systems. However, particularly among the protistan plankton of the lower
trophic levels, the distinction between “phytoplankton”
and “zooplankton” is not clear-cut. Mixotrophic nutrition
among plankton has been conceptualized as a range of
alternative nutritional strategies that fall somewhere
between pure photoautotrophy and heterotrophy (Jones,
1994), including the auxotrophic requirement of most
phototrophs for organic cofactors (vitamins), the saprophytic uptake of organic molecules by phototrophs,
phagotrophic ingestion of prey by phototrophic species,
and the stealing of chloroplasts from prey species that
is referred to as kleptoplastidy. It has become clear that
such a classification would include nearly all protistan
plankton, so recently the term “mixotrophic plankton”
has been reserved for those species using a combination
of photosynthesis and phagotrophy (Flynn et al., 2012).
Stoecker (1998) delineated three functional types
(model I, II, and III) of phagotrophic mixotrophs based
on functional responses to prey and nutrients and on the
relative roles/predominance of heterotrophy and autotrophy, functional responses of grazing to light and nutrients, and the possible benefits of mixotrophic nutrition
to the organisms. An “ideal” mixotroph (model I) is
equally adept as either an autotroph or a heterotroph.
Phagotrophic “algae” (model II) are primarily photosynthetic, but ingest prey under certain conditions. Photosynthetic “protozoa” (model III) are primarily
phagotrophic, but can photosynthesize under certain
conditions using either their own plastids or those they
sequester as “kleptochloroplasts” (Stoecker, 1998).
Mixotrophic plankton are widespread in estuarine ecosystems, but because of the inherent metabolic and functional diversity within this group (both within and
between species), their impact on pelagic food webs is
challenging to estimate (Stickney et al., 2000; Flynn
et al., 2012), as are the potential effects of climate change
on the role of mixotrophic plankton in pelagic nutrient
and energy cycling (Wilkens et al., 2012).
MIXOTROPHIC PLANKTON
447
167, 55–61.
Sawlowlicz, Z., 1993. Pyrite framboids and their development:
a new conceptual mechanism. Geologische Rundschau, 82,
148–156.
Schieber, J., 2002. Sedimentary pyrite: a window into the microbial
past. Geology, 30, 531–534.
Schippers, A., and Jørgensen, B. B., 2002. Biogeochemistry of
pyrite and iron sulfide oxidation in marine sediments.
Geochimica et Cosmochimica Acta, 66(1), 85–92.
Schneiderhohn, H., 1923. Chalkographische Untersuchung des
Mansfelder Kupferschiefers. Neues Jahrbuch für Geologie und
Paläontologie, 47, 1–38.
Semeniuk, V., 1980. Quaternary stratigraphy of the tidal flats King
Sound, WA. Journal of the Royal Society of Western Australia,
63, 65–78.
Semeniuk, V., 2010. A note on calcite precipitates as encrustations
around sea rush roots and as microlaminae in high tidal zones
of western Leschenault Inlet estuary. Journal of the Royal Society of Western Australia, 93, 195–199.
Semeniuk, V., Semeniuk, T. A., and Unno, J., 2000. The
Leschenault Inlet estuary – an overview. Journal of the Royal
Society of Western Australia Special Issue on the Leschenault
Inlet Estuary, 83, 207–228.
Simkiss, K., and Wilbur, K. M., 1989. Biomineralization: Cell Biology and Deposition. London: Academic Press.
Sumper, M., and Kroger, N., 2004. Silica formation in diatoms: the
function of long-chain polyamines and silaffins. Journal of
Materials Chemistry, 14, 2059–2065.
Sunagawa, I., Endo, Y., and Nakai, N., 1971. Hydrothermal synthesis of framboidal pyrite. Society of Mining Geologists of Japan
(Special Issue), 2, 10–14.
Sweeney, R. E., and Kaplan, I. R., 1973. Pyrite framboid formation;
laboratory synthesis and marine sediments. Economic Geology,
68(5), 618–634.
van Beusekom, J. E. E., and de Jonge, V. N., 1997. Transformation
of phosphorus in the Wadden Sea: Apatite formation. Deutsche
Hydrografische Zeitschrift, 49, 297–305.
von der Borch, C. C., Rubin, M., and Skinner, B. J., 1964. Modern
dolomite from South Australia. American Journal of Science,
262, 1116–1118.
von der Borch, C. C., Lock, D., and Schwebel, D., 1975. Groundwater formation of dolomite in the Coorong region of South
Australia. Geology, 3, 283–285.
Warner, G. F., 1977. The Biology of Crabs. London: Elek Science.
Wilkin, R. T., and Barnes, H. L., 1997a. Pyrite formation in an
anoxic estuarine basin. American Journal of Science, 297(6),
620–650.
Wilkin, R. T., and Barnes, H. L., 1997b. Formation processes of
framboidal pyrite. Geochimica et Cosmochimica Acta, 61(2),
323–339.
Wilkin, R. T., Barnes, H. L., and Brantley, S. L., 1996. The size distribution of framboidal pyrite in modern sediments: an indicator
of redox conditions. Geochimica et Cosmochimica Acta, 60(20),
3897–3912.
Wopenka, B., and Pasteris, J. D., 2005. A mineralogical perspective
on the apatite in bone. Materials Science and Engineering C, 25,
131–143.
Cross-references
Biogenous Sediment
Diagenesis
Microbial Degradation
Nitrification
Nutrient Dynamics
Shell Beds
MIXOTROPHIC PLANKTON
Jason E. Adolf
Department of Marine Science, University of Hawaii at
Hilo, Hilo, HI, USA
Definition
Mixotrophic plankton are those that use a combination of
phototrophic and heterotrophic nutrition.
Mixotrophic plankton and our evolving
view of pelagic foodwebs
Traditionally, oceanographers and limnologists categorize plankton as “phytoplankton” and “zooplankton,”
implying functional roles analogous to plants and animals, respectively, in terrestrial systems. However, particularly among the protistan plankton of the lower
trophic levels, the distinction between “phytoplankton”
and “zooplankton” is not clear-cut. Mixotrophic nutrition
among plankton has been conceptualized as a range of
alternative nutritional strategies that fall somewhere
between pure photoautotrophy and heterotrophy (Jones,
1994), including the auxotrophic requirement of most
phototrophs for organic cofactors (vitamins), the saprophytic uptake of organic molecules by phototrophs,
phagotrophic ingestion of prey by phototrophic species,
and the stealing of chloroplasts from prey species that
is referred to as kleptoplastidy. It has become clear that
such a classification would include nearly all protistan
plankton, so recently the term “mixotrophic plankton”
has been reserved for those species using a combination
of photosynthesis and phagotrophy (Flynn et al., 2012).
Stoecker (1998) delineated three functional types
(model I, II, and III) of phagotrophic mixotrophs based
on functional responses to prey and nutrients and on the
relative roles/predominance of heterotrophy and autotrophy, functional responses of grazing to light and nutrients, and the possible benefits of mixotrophic nutrition
to the organisms. An “ideal” mixotroph (model I) is
equally adept as either an autotroph or a heterotroph.
Phagotrophic “algae” (model II) are primarily photosynthetic, but ingest prey under certain conditions. Photosynthetic “protozoa” (model III) are primarily
phagotrophic, but can photosynthesize under certain
conditions using either their own plastids or those they
sequester as “kleptochloroplasts” (Stoecker, 1998).
Mixotrophic plankton are widespread in estuarine ecosystems, but because of the inherent metabolic and functional diversity within this group (both within and
between species), their impact on pelagic food webs is
challenging to estimate (Stickney et al., 2000; Flynn
et al., 2012), as are the potential effects of climate change
on the role of mixotrophic plankton in pelagic nutrient
and energy cycling (Wilkens et al., 2012).
MIXOTROPHIC PLANKTON
447