9
amino acid
ALK ~age-Iength key.
alkalinity total (or titration) alkalinity, (AT)' was defined by N.W. Rakestraw as
the excess of bases (proton acceptors) over acids (proton donors) in seawater. The expression for total alkalinity is commonly presented as
AT = [HCOd+2[C032-)+[B(OH)4-)+[OH-)-[W). This expression defines
the equivalence point for an alkalinity determination as the point (pH 4.5) at
which [WI = [HC0 3 -)+2[C0 3 2-)+[B(OHk)+ [OH-) . Total inorganic carbon
(C T ), is expressed as C T = [H 2 C0 3 )+[HCOd+[C0 3 2-). Both quantities AT and
C T can be precisely determined from a single, potentiometric titration. They
playa fundamental role in the study of the oceanic inorganic carbonate system.
allochthonous from elsewhere, as opposed to autochthonous: produced in situ. Used,
e.g., for organic matter that may be imported from elsewhere, or for organisms.
allometric growth ~growth.
allopatric speciation ~speciation (bioi .).
aluminum (AI) is after oxygen and silicon the most abundant in the earth's crust
element (about 8.3 % Al by weight). Terrigenous marine sediments consist
largely of aluminosilicates, among which the various clay minerals produced
through chemical weathering. In seawater dissolved Al exists mostly as the
hydrolyzed AI(OHh and Al(OHk, whereas speculation exists on finely dispersed colloidal forms. Dissolved concentrations range from 0.5 nmoll- 1 or
less in deep waters of the central North Pacific to about 150 nmoll- 1 in deep
Mediterranean waters. The latter waters exhibit a direct relationship
between dissolved Al and dissolved Si, whereas in the Atlantic and Pacific
Oceans there appears to be an inverse relation between dissolved Al and Si.
Dissolved Al in seawater appears to be controlled by a combination of biological and nonbiological processes.
ambergris ~whale fishery.
ambulacra radial bands at the surface of Echinodermata from which tube feet are
projecting.
ambulacral groove groove in Echinodermata in which rows of tube feet are situated.
amino acid white, crystalline organic compound containing a basic amino
(NH 2 ) group attached to the same carbon atom that holds the acidic carboxyl (COOH) group, to be isolated from protein hydrolyzates. Amino acids
may be classified according to the number of their amino and carboxyl
groups: (1) acidic amino acids, containing an excess of carboxyl groups
amino acid
ALK ~age-Iength key.
alkalinity total (or titration) alkalinity, (AT)' was defined by N.W. Rakestraw as
the excess of bases (proton acceptors) over acids (proton donors) in seawater. The expression for total alkalinity is commonly presented as
AT = [HCOd+2[C032-)+[B(OH)4-)+[OH-)-[W). This expression defines
the equivalence point for an alkalinity determination as the point (pH 4.5) at
which [WI = [HC0 3 -)+2[C0 3 2-)+[B(OHk)+ [OH-) . Total inorganic carbon
(C T ), is expressed as C T = [H 2 C0 3 )+[HCOd+[C0 3 2-). Both quantities AT and
C T can be precisely determined from a single, potentiometric titration. They
playa fundamental role in the study of the oceanic inorganic carbonate system.
allochthonous from elsewhere, as opposed to autochthonous: produced in situ. Used,
e.g., for organic matter that may be imported from elsewhere, or for organisms.
allometric growth ~growth.
allopatric speciation ~speciation (bioi .).
aluminum (AI) is after oxygen and silicon the most abundant in the earth's crust
element (about 8.3 % Al by weight). Terrigenous marine sediments consist
largely of aluminosilicates, among which the various clay minerals produced
through chemical weathering. In seawater dissolved Al exists mostly as the
hydrolyzed AI(OHh and Al(OHk, whereas speculation exists on finely dispersed colloidal forms. Dissolved concentrations range from 0.5 nmoll- 1 or
less in deep waters of the central North Pacific to about 150 nmoll- 1 in deep
Mediterranean waters. The latter waters exhibit a direct relationship
between dissolved Al and dissolved Si, whereas in the Atlantic and Pacific
Oceans there appears to be an inverse relation between dissolved Al and Si.
Dissolved Al in seawater appears to be controlled by a combination of biological and nonbiological processes.
ambergris ~whale fishery.
ambulacra radial bands at the surface of Echinodermata from which tube feet are
projecting.
ambulacral groove groove in Echinodermata in which rows of tube feet are situated.
amino acid white, crystalline organic compound containing a basic amino
(NH 2 ) group attached to the same carbon atom that holds the acidic carboxyl (COOH) group, to be isolated from protein hydrolyzates. Amino acids
may be classified according to the number of their amino and carboxyl
groups: (1) acidic amino acids, containing an excess of carboxyl groups