The Ecology of the Seagrasses of South Florida - USGS National ...

of *- Udotea, and Acetabuf aria emerge, the study of cpiph tes has suf-
Pr t as much mud as Penicil- fered from what Harlin (19803 described as
lus in the same locations.
the "bits and pieces" approach.
Xn tine Bight of Abaco, PIeumann and An annotated list of 113 s~ecies of
land (19%) calculated that the growth of algae found epiphytic on turtle grass in
-, and Hali~eda south Florida was compiled by Hum (1964).
produced 1,s e amou Of these only a few were specific to seaand
Walimeda sand now in the basin and grasses; most were also found on other
ttlat T3-typical Bahamian Bank lagoon, plants or sol id substrate, later, Ball ancalcareous
green algae alone produced more tlne and Hum (1975) reported 66 species
sediment than could be accommodatedr Bash of benthic algae which were epiphytic on
(1979) measured the rates of organfc and the seagrasses of the west coast of Florinorganic
production af cal careous siphon- ida. Rhodophyta comprised 45% of the
ntes 4n Card Sound, Florida, using several total, Phaeophytas were only 12% and
techniques, &ganic production was 1 ow in Chl oroptrytas and Cyanophytas each reprethds
lagoon, rangfng from &,6 to 38.4 g sented 21% of the species. Warlin (1980)
ash free dry weight /mi/yr, and 4.2 to compfled from 27 published works a species
16,8 g CaCO,/mi/yr Pcrr all the specles list of the! nlicroalgae, macroalqae, and
conbf nad,
animals that have been recorded as epiphytic
on seaprasses. The algal lists are
In addftian to the calcareous algae, comprehensive, but none of the reports
several algae arc present In grass beds as surveyed by kHuw list the epiphytic inverlarge
clumps of detached drift algae; the tebrates frnn south Florida.
lirrnst abundant belongs to the genus Laur3n2
cf&, Iha areal praductfon of ehesmgae llarlin (1975) If sted the factors
?%*mlow coinpar& with .the Seagrasses. Jas- i nfluencing distribution and abundance of
sclyn (1975) est Jmiltsd the production of epiphytes as:
Lauren$i&- fn Card Sound to average about
WUB %I*
8,1 q Z$r wcfght /tn2/yr which was less (1) Physical substrate
than 1% of the J,lOO g/mJJyr estir?al& by (2) Access to photic zone
Pherrharrrl et 91. (1W3) for ttirtle grass (3) F free ride tt.\rough ~ovinq
fre)~:i the $d!ile area. waters
(4) Nutrient exchange with host
The least studied cmnponents OF the (5) Ornanic carbon source
algal flora! are the benthSc nicroalpae.
In stulffer of" benthic production through- The availability of a relatively stable
out %he CarSbbean, Runt et nl. (1971) gal- (albej t somewhat swaying) substrate seens
c:ulatatd the productSon in Caribbean r,@di- d0 be the most fundamental sole played by
flarpfll~ f;O average 8.1 rrg C/mt/hr (range = the seagrasses. Thc majority of the epi-
2,5 to 13*8 mg) igsivlg uptake. Py cop\- phytic species js sessile and needs a surjrdrfson,
sedlrnentr; frorn the Ff ar-ida Keys face far attachnent. The turnover of the
yff?lde?d 0*3 t0 7,4 rng C/mZ'/hr Fixation, cpiphyejc cmunity is relatively rapid
These vl;xlucs were ~q~iv~lent to the pro- since the lifetit~c of a sinqle leaf is
L~1~tSt~lvl 4n the vcStter colug;;rn, ferguson lialited. A typical turtle Grass leaf has a
@t $1. (19C05 hricnfly reviet~cd rsicroatgal lifetime of 30 to 60 days (Xienan 197%).
produckfon valucs and fndjcatcd that light After a leaf cmcrqes there is a period heand
themal Snhibf tion occur, particu- fore epiphytic organisms appear. This nay
7 arfy in stimfiicr. be due to the relatively svoot6 surface or
the producticn of sane antihistic colnpound
by the leaf. On tropical seagrasses the
&9J2!y>J~&a2
heaviest coatings af epiphytes only occur
after the leaf has heen colonized by the
One of the main functions far &i@h coral l fne red algae, Fos1 fe11ii or -- !?elah@-
%ca$grW3SS@s have been recognir~d has he@~ G. The caral'line sk~Teton of thcse algae
the ahil ity to provlde a substrate for the may fom a protective barrier as well as a
attachment of epiphytic organisms, Al- sui tahly roughened and adherent sttrface
thnuqh unffyirtg patterns arc beginning to for epiphytes (Figure 15).
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