Galaxea, Journal of Coral Reef Studies
Online ISSN : 1883-3969
Print ISSN : 1883-0838
ISSN-L : 1883-0838
Volume 16 , Issue 1
Showing 1-8 articles out of 8 articles from the selected issue
Original paper
  • Yvonne SAWALL, Somkiat KHOKIATTIWONG, Jamaluddin JOMPA, Claudio RICHTE ...
    2014 Volume 16 Issue 1 Pages 1-10
    Published: 2014
    Released: October 10, 2014
    In situ incubation experiments, complemented by tissue analyses, were conducted with the coral Porites lutea at four sites featuring contrasting environmental conditions: two shallow (3m) reefs in Spermonde Archi-pelago (Indonesia) subjected to coastal pollution (Lae Lae, LL) and oligotrophic waters (Bonebatang, BBA), respectively; a deep (20m, KR-D) and a shallow (7m, KR-S) reef at off-shore Ko Racha (KR) in the Andaman Sea (Thailand) subjected to pulsed upwelling. Mean tem-perature varied only little (29-30°C). While most tis-sue parameters responded to light and nutrient changes as ex-pected, metabolic rates revealed surprising patterns: 3-fold elevated calcification occurred at KR-S compared to all other sites despite reduced gross photosynthesis. Fur-ther-more, equal photosynthesis occurred in 7 and 20m depth at KR, despite a 5-fold reduction in light intensity, which could not be solely ascribed to photo-acclimation processes, such as increased cell-specific chlorophyll a in 20m depth. These findings support the notion of a highly flexible species and indicate that this might partly be ascribed to a strong variation in the internal turnover of oxygen and nutrients between coral host and zooxanthellae, meaning a strong variation in the rates of energy ac-quisition. Those differences are particularly difficult to determine in situ, but require greater attention in the future in order to enhance our understanding of metabolic pro-cesses and acclimatization abilities.
    Download PDF (813K)
Original paper
  • Frederico Tapajós de Souza TÂMEGA, Davide BASSI, Marcia Abreu de Olive ...
    2014 Volume 16 Issue 1 Pages 21-31
    Published: 2014
    Released: December 27, 2014
    Rhodolith beds are distributed from the north-eastern to the southeastern Brazilian continental shelf, constituting the largest extension of coralline algal de-posits in the world. Little is known about the deep rho-dolith beds within the Campos Basin: the largest oil pro-duction area in the country and a priority area for marine life conservation. This study illustrates a deep rhodolith bed covering about 15km2 of a 40km2-area in the Peregrino oil field sampled at 100-106m water depth. Coralline algae are the dominant components on the living rhodolith surfaces associated with subordinate bryozoans, cnidarids, brachiopods and porifers. In some inner parts of the coralline algal nodules, encrusting acervulinid fora-minifera are the main nodule contributors. Through accel-erator mass spectrometric analysis, radiocarbon age esti-mates show that the range in ages between the living outer rhodolith parts and within 3mm from it the rhodoliths is ca. 4,700 years. This suggests that a proportion of fossil rhodoliths had been recolonized after periods of burial and/or erosion. The present-day Peregrino rhodolith bed played a fundamental ecological role in the Brazilian con-tinental shelf’s benthic habitats for thousands of years.
    Download PDF (950K)