Bottom Plant Associations
149
lithothamnion dinotus, Lithothamnion ruptile, and Tanarea prototypa (Van
den Hoeck et al. 1978). These opportunistic crustose calcareous algae not
only form basic carbonate constructions in turbulent reef zones at the windward reef edge and on their windward slopes, but also compose a main
portion of the total algal biomass in these zones, especially on reefs with
algal ridges along their windward edge (Womersly and Bailey 1969; Littler
1972; Adey and Macintyre 1973). Thus they accomplish an important function of reef builders, which mount and cement the reef constructions in the
physically most stressed zones. The bbnching corallines are also widespread
on reefs, inhabiting the trenches, the caverns, and places between the coral
colonies. They participate also in the ~ormation of periphytonic communities
and in the consolidation of reef lime constructions, producing a bulk of
crumbly calcareous material (Adey and Vassar 1975; Wanders 1976b).
The seagrasses inhabit mostly the soft bottom biotopes in lagoons or in
reef-flat zones. They form often dense thickets, thus dominating there by
biomass (Table 4.14). The parimary production in bottom biotopes with the
domination of seagrasses largely exceeds that of the thickets of seaweeds or
corals. Their leaves and litter, formed after their decay are a significant
source of feeding for reef fauna (Zieman et al. 1979). The reef seagrasses
include the genera. thalassia (T. testudinium, T. hemprichii) , Thalassiodendron (T. ciliattlm) , Zostera (Z. marina, Z. capricorni) , Halophila (H.
ballonis, H. ovalis, H. minor, H. stipulacea) , Halodule (H. wrightii, H.
universus) , Cymodocea (c. serrulata C. rotundata) , Syringodium (S. filiformis, S. isoetifolium), and Enhalus (E. ciliatum), Posydonia (P. australis).
On the Pacific reefs the dominating seagrasses are Thalassiodendron ciliatum,
T. hemprichii and Halophila stipulacea, while at the reef of the Western
Atlantic the turtle grass Thalassia testudinum is most widespread (Quasim
and Bhattathiri 1971; Zieman 1975; Tsuda 1977b, 1979; Norris and Bucher
1982). The seagrasses appear usually at a late stage of succession of benthic
plant communities in the soft bottom biotopes (Williams 1981).
At many reefs the plant associations include also the mangroves (Clough
1982; Lugo and Snedeaker 1974; Teas 1983). Their leaves and roots are an
important source of organic detritus (Colley et al. 1962; Lugo et al. 1975).
Mangroves are trees and shrubs 3-15 m high. Their base parts are formed
by branching supporting roots and by air roots. They form dense forests and
thickets at reef shallows and in the intertidal stripes and keys, especially in
coastal lagoons of barrier reefs (Forsberg 1976) and on low intertidal
plateaus of the Indo-Pacific reefs (Stoddart 1980). Different mangrove
species taxonomically belong to different familes of angiosperms. Within a
separate reef system 10-20 species of mangroves could be found (Bunt et al.
1979; Stoddart 1980; Buckley 1982; Boto et al. 1984). But their local forests
are formed, as a rule, by some single species of one of the following genera:
Rhizophora, Avicennia, Bruguiera, Ceriops, Laguncularia, Sonneratia,
Luminitzera, and Conycarpus. Their different species are adapted to specific
environemental conditions and to definite types of bottom sediments.
149
lithothamnion dinotus, Lithothamnion ruptile, and Tanarea prototypa (Van
den Hoeck et al. 1978). These opportunistic crustose calcareous algae not
only form basic carbonate constructions in turbulent reef zones at the windward reef edge and on their windward slopes, but also compose a main
portion of the total algal biomass in these zones, especially on reefs with
algal ridges along their windward edge (Womersly and Bailey 1969; Littler
1972; Adey and Macintyre 1973). Thus they accomplish an important function of reef builders, which mount and cement the reef constructions in the
physically most stressed zones. The bbnching corallines are also widespread
on reefs, inhabiting the trenches, the caverns, and places between the coral
colonies. They participate also in the ~ormation of periphytonic communities
and in the consolidation of reef lime constructions, producing a bulk of
crumbly calcareous material (Adey and Vassar 1975; Wanders 1976b).
The seagrasses inhabit mostly the soft bottom biotopes in lagoons or in
reef-flat zones. They form often dense thickets, thus dominating there by
biomass (Table 4.14). The parimary production in bottom biotopes with the
domination of seagrasses largely exceeds that of the thickets of seaweeds or
corals. Their leaves and litter, formed after their decay are a significant
source of feeding for reef fauna (Zieman et al. 1979). The reef seagrasses
include the genera. thalassia (T. testudinium, T. hemprichii) , Thalassiodendron (T. ciliattlm) , Zostera (Z. marina, Z. capricorni) , Halophila (H.
ballonis, H. ovalis, H. minor, H. stipulacea) , Halodule (H. wrightii, H.
universus) , Cymodocea (c. serrulata C. rotundata) , Syringodium (S. filiformis, S. isoetifolium), and Enhalus (E. ciliatum), Posydonia (P. australis).
On the Pacific reefs the dominating seagrasses are Thalassiodendron ciliatum,
T. hemprichii and Halophila stipulacea, while at the reef of the Western
Atlantic the turtle grass Thalassia testudinum is most widespread (Quasim
and Bhattathiri 1971; Zieman 1975; Tsuda 1977b, 1979; Norris and Bucher
1982). The seagrasses appear usually at a late stage of succession of benthic
plant communities in the soft bottom biotopes (Williams 1981).
At many reefs the plant associations include also the mangroves (Clough
1982; Lugo and Snedeaker 1974; Teas 1983). Their leaves and roots are an
important source of organic detritus (Colley et al. 1962; Lugo et al. 1975).
Mangroves are trees and shrubs 3-15 m high. Their base parts are formed
by branching supporting roots and by air roots. They form dense forests and
thickets at reef shallows and in the intertidal stripes and keys, especially in
coastal lagoons of barrier reefs (Forsberg 1976) and on low intertidal
plateaus of the Indo-Pacific reefs (Stoddart 1980). Different mangrove
species taxonomically belong to different familes of angiosperms. Within a
separate reef system 10-20 species of mangroves could be found (Bunt et al.
1979; Stoddart 1980; Buckley 1982; Boto et al. 1984). But their local forests
are formed, as a rule, by some single species of one of the following genera:
Rhizophora, Avicennia, Bruguiera, Ceriops, Laguncularia, Sonneratia,
Luminitzera, and Conycarpus. Their different species are adapted to specific
environemental conditions and to definite types of bottom sediments.