| dc.description.abstract | Coral reefs integrate the major productivity and species richness
ecosystems in the planet, provide ecosystem services that thousants of people
depend on. Macroalgae are important in these enviroments and may be utilized
as bioindicators. The presente study caracterized the seaweed community of
Maracajau reef (5°24'40" S - 35°18'40" W). Four stations were defined to data
collect (E1: Inside border; E2: Reef center; E3: Tourism utilization area; E4:
Outside border). The photoquadrat method was applied to register images of
marine flora along transects (45 images on each station). The present
macroalgae in each image was identified at taxonomic level of gender. A similarity
analyisis was performed (Jaccard Index) and the CPCe 4.1 software was utilized
to obtain cover of macroalgae functional groups in each station. A total of 13
genders of macroalgae were identified, Dictyopteris, Dictyota, Padina,
Sargassum, Lobophora, Udotea, Caulerpa, Gelidium, Octhodes, Gracilaria,
Laurencia, Jania and Lithothamium. The detected functional groups were foliose,
leathery, corticated, articulated calcareous and crustose algae. A seagrass
species (Halodule wrightii) and other organisms were identified. The E1 is
covered mainly by foliose macroalgae (20,18%) and seagrass (34,3%). The E2
presented the major foliose macroalgae coverage (49,35%), crustose calcareous
algae (17,78%) and Turf (13,78%) were also representatives groups. The tourism
area (E3) showed Turf (26,62%) and foliose macroagae (24,51%) coverage,
however soft coral Palythoa caribaeroum had the major percentage (40,98%).
The composition of outside border (E4) presented calcareous crustose algae
(53,30%), foliose algae (11,02%) and leathery algae (9,43%). The Jaccard Index
showed that E2 and E3 presented major similarity (0,714). The outside border is
more similar with E3 (0,625) and E2 (0,5) than inside border, E1 (0,214). The E1
showed lowest similarity with the others. The morfofunctional groups as leathery
and crustose calcareous algae occurred mainly in the outside border, revealing
more tolerance from waves and currents disturbance. The foliose algae occurred
along the entire reef, however the central area without tourism showed major flora
from this group. The outside border presented major abundance of corticated
algae. The flora showed differents compositions along the Maracajau reef, that
changed according to substrate and hydrodynamics. | |
