Cross-references
Algae, Coralline
Aragonite
Bindstone
Bioherms and Biostromes
Bryozoa
Calcite
Coral Reef, Definition
Devonian Reef Complexes of the Canning Basin
Foraminifera
Fossil Coralline Algae
Molluscs
Permian Capitan Reef System
Reefal Microbial Crusts
Rhodoliths
Seagrasses
Sponges
Stromatolites
Submarine Lithification
BINDSTONE
Peter Flood
University of New England, Armidale, NSW, Australia
Bindstone is a modification proposed by Embry and
Klovan (1971) to the Dunham (1962) Boundstone type
of limestone where the framework organisms were
encrusting and binding the sediment.
Bibliography
Dunham, R. J., 1962. Classification of carbonate rocks according to
depositional texture. In Ham, W. E. (ed.), Classification of Carbonate Rocks: American Association of Petroleum Geologists
Memoir, pp. 108–121.
Embry, A. F., and Klovan, J. E., 1971. A Late Devonian reef tract on
Northeastern Banks Island. NWT: Canadian Petroleum Geology
Bulletin, Vol. 19, pp. 730–781.
Cross-references
Classification of Carbonates
BIOEROSION
Pat Hutchings
Australian Museum, NSW, Sydney, Australia
Definition
Bioerosion can be defined as the destruction and removal
of consolidated mineral or lithic substrate by the direct
action of organisms (Neumann, 1966) and is complemented by physical and chemical processes of erosion. This
review deals only with the removal of substrate from coral
reefs and concentrates on modern day reefs. However, there
is an extensive literature on boring organisms on fossil
reefs, for a review see Tapanila (2008) and the agents and
mechanisms of boring seem similar on these reefs to those
occurring on modern day reefs (Wood, 1999).
Introduction
Bioerosion is a natural process occurring on all reefs
although rates and agents may vary across the reef and
together with reef growth which also varies, results in
them being dynamic systems. It is the balance between
these two processes which determines the overall shape
of the reef together with physical and chemical erosion
of the coral substrate. Bioerosion includes the removal of
surface substrate by grazing organism (Acanthaster
planci; Sponges) and the loss of substrate by boring organisms which produces a continual supply of lagoonal and
inter-reefal sediments. While reef growth has been well
studied (Barnes and Chalker, 1990), bioerosion has been
relatively poorly studied. Although this situation is likely
to be rectified, as reefs are increasingly being impacted
by anthropogenic effects, which often results in changes
in the balance between rates of reef growth and reef
destruction, with the latter far exceeding reef growth in
many parts of the world (Pari et al., 2002; Sheppard
et al., 2002). This loss of substrate may have severe biological, economic, and social consequences each of which
will be discussed later.
A wide range of organisms are capable of boring
into coral substrate and this includes both macro and
microborers with recruitment via pelagic larvae or propagules (McCloskey, 1970). Reef building corals have
a thin veneer of living coral polyps over the coral skeleton,
and these are active carnivores and can capture any larvae
of borers which settle on them using their nematocysts.
Larvae can also become trapped in the ciliary feeding currents generated by the polyps and carried to the mouth and
eaten. This ensures that few larvae settle on live polyps,
instead they settle on damaged polyps or any dead areas
of the colony or at the base of the colony where typically
there is no veneer of living coral. However, once the colony dies, for example, as a result of disease (Sussman
et al., 2008), bleaching (Pratchett et al., 2008), predation by Crown of Thorns starfish (Acanthaster planci)
(DeVantier and Done, 2007), the gastropod mollusc
Drupella spp., (Morton and Blackmore, 2009), or by other
coral predators (Rotjan, and Lewis, 2008), or from the
effects of storms (López-Victoria and Zea, 2004), the substrate is rapidly colonized by microborers which conditions the surface and facilitates recruitment of a suite of
macroborers.
Microborers
Components and processes
A diverse array of micro-organisms colonize coral substrates including cyanobacteria, algae, and fungi; for a
review of their taxonomy, see Kobluk and Kahle (1977)
and for a review of their boring activity, see Tribollet
BIOEROSION
139
Algae, Coralline
Aragonite
Bindstone
Bioherms and Biostromes
Bryozoa
Calcite
Coral Reef, Definition
Devonian Reef Complexes of the Canning Basin
Foraminifera
Fossil Coralline Algae
Molluscs
Permian Capitan Reef System
Reefal Microbial Crusts
Rhodoliths
Seagrasses
Sponges
Stromatolites
Submarine Lithification
BINDSTONE
Peter Flood
University of New England, Armidale, NSW, Australia
Bindstone is a modification proposed by Embry and
Klovan (1971) to the Dunham (1962) Boundstone type
of limestone where the framework organisms were
encrusting and binding the sediment.
Bibliography
Dunham, R. J., 1962. Classification of carbonate rocks according to
depositional texture. In Ham, W. E. (ed.), Classification of Carbonate Rocks: American Association of Petroleum Geologists
Memoir, pp. 108–121.
Embry, A. F., and Klovan, J. E., 1971. A Late Devonian reef tract on
Northeastern Banks Island. NWT: Canadian Petroleum Geology
Bulletin, Vol. 19, pp. 730–781.
Cross-references
Classification of Carbonates
BIOEROSION
Pat Hutchings
Australian Museum, NSW, Sydney, Australia
Definition
Bioerosion can be defined as the destruction and removal
of consolidated mineral or lithic substrate by the direct
action of organisms (Neumann, 1966) and is complemented by physical and chemical processes of erosion. This
review deals only with the removal of substrate from coral
reefs and concentrates on modern day reefs. However, there
is an extensive literature on boring organisms on fossil
reefs, for a review see Tapanila (2008) and the agents and
mechanisms of boring seem similar on these reefs to those
occurring on modern day reefs (Wood, 1999).
Introduction
Bioerosion is a natural process occurring on all reefs
although rates and agents may vary across the reef and
together with reef growth which also varies, results in
them being dynamic systems. It is the balance between
these two processes which determines the overall shape
of the reef together with physical and chemical erosion
of the coral substrate. Bioerosion includes the removal of
surface substrate by grazing organism (Acanthaster
planci; Sponges) and the loss of substrate by boring organisms which produces a continual supply of lagoonal and
inter-reefal sediments. While reef growth has been well
studied (Barnes and Chalker, 1990), bioerosion has been
relatively poorly studied. Although this situation is likely
to be rectified, as reefs are increasingly being impacted
by anthropogenic effects, which often results in changes
in the balance between rates of reef growth and reef
destruction, with the latter far exceeding reef growth in
many parts of the world (Pari et al., 2002; Sheppard
et al., 2002). This loss of substrate may have severe biological, economic, and social consequences each of which
will be discussed later.
A wide range of organisms are capable of boring
into coral substrate and this includes both macro and
microborers with recruitment via pelagic larvae or propagules (McCloskey, 1970). Reef building corals have
a thin veneer of living coral polyps over the coral skeleton,
and these are active carnivores and can capture any larvae
of borers which settle on them using their nematocysts.
Larvae can also become trapped in the ciliary feeding currents generated by the polyps and carried to the mouth and
eaten. This ensures that few larvae settle on live polyps,
instead they settle on damaged polyps or any dead areas
of the colony or at the base of the colony where typically
there is no veneer of living coral. However, once the colony dies, for example, as a result of disease (Sussman
et al., 2008), bleaching (Pratchett et al., 2008), predation by Crown of Thorns starfish (Acanthaster planci)
(DeVantier and Done, 2007), the gastropod mollusc
Drupella spp., (Morton and Blackmore, 2009), or by other
coral predators (Rotjan, and Lewis, 2008), or from the
effects of storms (López-Victoria and Zea, 2004), the substrate is rapidly colonized by microborers which conditions the surface and facilitates recruitment of a suite of
macroborers.
Microborers
Components and processes
A diverse array of micro-organisms colonize coral substrates including cyanobacteria, algae, and fungi; for a
review of their taxonomy, see Kobluk and Kahle (1977)
and for a review of their boring activity, see Tribollet
BIOEROSION
139