Carbonate Dehydratase in Marine Organisms of the Great Barrier Reef

1976 ◽  
Vol 3 (1) ◽  
pp. 113 ◽  
Author(s):  
D Graham ◽  
RM Smillie
Keyword(s):  
Calcium Carbonate ◽  
Great Barrier Reef ◽  
Sea Water ◽  
Carbonic Anhydrase Activity ◽  
Enzymic Activity ◽  
Barrier Reef ◽  
Pocillopora Damicornis ◽  
Blue Green Algae ◽  
Calcium Carbonate Deposition ◽  
Dehydratase Activity

Carbonate dehydratase (EC 4.2.1.1, other name 'carbonic anhydrase') activity was found in 28 of 29 species of marine algae and angiosperms and in a mixed culture of phytoplankton collected in the vicinity of Lizard Island on the Great Barrier Reef of Australia. The species included 13 member- of the Chlorophyta, 4 of the Phaeophyta, 7 of the Rhodophyta, 2 of the Cyanophyta and 3 subs merged marine angiosperms. One of the two blue-green algae showed no detectable enzymic activity. The levels of activity ranged from 100 to 4800 units per milligram chlorophyll and were generally comparable with those of terrestrial angiosperms based on chlorophyll content, but were only a small fraction when compared on the basis of fresh weight. Culture of the green alga Chlorodesmis fastigiata in 'CO2-free' sea water (1.4 mg CO2 per litre) for 4 h did not lead to an induction of carbonate dehydratase activity. Some of the species of algae producing calcium carbonate contained the highest activities recorded but others had low activities. A correlation between high carbonate dehydratase activity and calcium carbonate deposition could not be adduced. Symbiotic zooxanthellae (Gymnodinium microadriaticum) of the hard coral Pocillopora damicornis and the clam Tridacna maxima also contained carbonate dehydratase (940 and 340 units per milligram chlorophyll, respectively). The host tissues contained about five times the activity of their respective zooxanthellae.

Feeding of Holothuria atra and Stichopus chloronotus on bacteria, organic carbon and organic nitrogen in sediments of the Great Barrier Reef

1982 ◽  
Vol 33 (2) ◽  
pp. 255 ◽  
Author(s):  
DJW Moriarty
Keyword(s):  
Organic Matter ◽  
Organic Carbon ◽  
Great Barrier Reef ◽  
Organic Nitrogen ◽  
Bacterial Biomass ◽  
Gut Contents ◽  
Barrier Reef ◽  
Muramic Acid ◽  
Blue Green Algae ◽  
Carbon And Nitrogen

Organic carbon and nitrogen and bacterial biomass were measured in the sediments and gut contents of H. atra and S. chloronotuson the Great Barrier Reef. Organic carbon averaged from 3.4 to 4.7 mg g-1, organic nitrogen from 0.20 to 0.31 mg g-1 and muramic acid from 1.4 to 3.3�g g-1 dry weight of surface sandy sediments. Bacterial biomass, determined by muramic acid measurements, averaged 3-8% of organic carbon in the sediments; blue-green algae accounted for 3-7% of muramic acid. Significantly higher values of organic carbon and nitrogen and muramic acid were found in foregut contents of the holothurians, indicating selective feeding on organically rich components of the sediment. Carbon values were 16-34% higher in the foregut than in the sediment. nitrogen values 35-111% higher and muramic acid values 33-300% higher. These values indicate that bacteria and nitrogenous components of the organic matter were selectively eaten. Values for organic carbon and nitrogen and muramic acid were generally lower in the hindgut than in the foregut, due to digestion and assimilation. Assimilation efficiencies averaged 30% for organic carbon, 40% for organic nitrogen and 30-40% for muramic acid (bacteria). Detritus (non-living matter) probably constituted 60-80% of the organic matter in the sediment and thus the food of the holothurians.

Gnathia grutterae sp. nov. (Crustacea, Isopoda, Gnathiidae) parasitising representatives of the Balistidae, Labridae and Tetraodontidae from Lizard Island, Great Barrier Reef, Australia

Zootaxa ◽  
2019 ◽  
Vol 2718 (1) ◽  
pp. 39 ◽  
Author(s):  
MARYKE L. FERREIRA ◽  
NICO J. SMIT ◽  
ANGELA J. DAVIES
Keyword(s):  
Great Barrier Reef ◽  
Sea Water ◽  
Anterior Part ◽  
Barrier Reef ◽  
Distinctive Features ◽  
Post Feeding ◽  
Lizard Island ◽  
Third Stage ◽  
Dorsal Area ◽  
A New Species

A new species of gnathiid was collected in March 2002 and November 2005 at Lizard Island, Great Barrier Reef, Australia. Third stage pranizae taken from balistid, labrid and tetraodontid fishes were maintained in fresh sea water until their moult into males (4 days post feeding) or females (11 days post feeding). Distinctive features of the adult male cephalosome include conical superior fronto-lateral processes directed anteriorly, with 4 simple setae in a row on each process, while the mediofrontal process is inferior with a shallow conical notch dividing the anterior part of mediofrontal process in two. The male mandible has a prominent internal lobe with small tubercles forming two rows from the internal lobe up to half the length of the mandible. The adult female has a broadly rounded cephalosome, with two pairs of long simple setae laterally on the mid-dorsal area, whereas the third stage praniza has a mandible with 9 teeth, comprising two small teeth at the tip and seven large, triangular, backwardly directed teeth on the mesial margin.

Temporal dynamics in coral bioindicators for water quality on coastal coral reefs of the Great Barrier Reef

2008 ◽  
Vol 59 (8) ◽  
pp. 703 ◽  
Author(s):  
Timothy F. Cooper ◽  
Peter V. Ridd ◽  
Karin E. Ulstrup ◽  
Craig Humphrey ◽  
Matthew Slivkoff ◽  
...  
Keyword(s):  
Water Quality ◽  
Coral Reefs ◽  
Great Barrier Reef ◽  
Temporal Dynamics ◽  
High Specificity ◽  
Barrier Reef ◽  
Pocillopora Damicornis ◽  
Skeletal Density ◽  
Massive Porites

There is a need to identify effective coral bioindicators that provide quantifiable links between changes in water quality and the condition of coastal coral reefs. Temporal variation in a range of coral bioindicators including symbiont density, concentration of chlorophyll a, skeletal density and colony brightness of Pocillopora damicornis, as well as colony brightness and density of macro-bioeroders of massive Porites spp. was examined for 2 years on a coastal coral reef of the Great Barrier Reef. The specificity to changes in water quality varied among bioindicators. For example, a 2.5-fold variation in symbiont density of P. damicornis was related strongly to mean 14-day sea surface temperature and seasonal changes in water quality, suggesting medium specificity to changes in water quality. In contrast, the density of macro-bioeroders in Porites did not vary seasonally but there were consistently more macro-bioeroders at the coastal than mid-shelf reference locations, suggesting high specificity of spatial differences in water quality. In situ measurements of benthic irradiance and turbidity allowed the quantification of potential stress thresholds for coastal corals. Our data suggest long-term turbidity >3 NTU leads to sublethal stress, whereas long-term turbidity >5 NTU corresponds to severe stress effects on corals at shallow depths.

Community structure of the fauna associated with the coral Pocillopora damicornis (L.) on the Great Barrier Reef

1980 ◽  
Vol 31 (2) ◽  
pp. 163 ◽  
Author(s):  
AD Austin ◽  
SA Austin ◽  
PF Sale
Keyword(s):  
Community Structure ◽  
Species Diversity ◽  
Great Barrier Reef ◽  
Physical Environment ◽  
Habitat Heterogeneity ◽  
Common Species ◽  
Barrier Reef ◽  
Pocillopora Damicornis ◽  
Species List ◽  
Number Of Individuals

The structure and composition of the infauna of the coral P. damicornis in the Capricorn Group, Great Barrier Reef, is examined. A total of 40 coral heads were sampled from four localities on two reefs and 951 individuals of 101 species were extracted. This is five times the species collected from P. damicornis in previous studies. A comprehensive species list is provided. Infauna was dominated by only a few species, 20 species accounting for 78% of individuals and 36 species recorded only as single individuals. Crustacea was the dominant taxon present, comprising 72% of species and 86% of individuals. Number of species and number of individuals show significant regressions with size of coral heads. Differences in physical environment at the four sites did not affect species diversity within coral heads. However, several common species only occurred within particular habitats. Species diversity is discussed briefly in relation to the behaviour of resident symbionts, random pelagic settlements of larvae, the size of target corals and habitat heterogeneity in coral heads.

δ13C Values in Marine Organisms from the Great Barrier Reef

1976 ◽  
Vol 3 (1) ◽  
pp. 25 ◽  
Author(s):  
CC Black ◽  
MM Bender
Keyword(s):  
Great Barrier Reef ◽  
Sea Water ◽  
Isotope Composition ◽  
Marine Ecosystem ◽  
Carbon Assimilation ◽  
Marine Organisms ◽  
Barrier Reef ◽  
Terrestrial Plants ◽  
Δ13c Values ◽  
Photosynthetic Organisms

The carbon isotope composition of marine organisms collected on the Great Barrier Reef near Lizard Island, Australia, was determined. Emphasis was placed on photosynthetic organisms including algae, zooxanthellae, angiosperms and symbiotic systems. The photosynthetic organisms had δ13C values ranging from -5.1 to -32.40,. Symbiotic systems and non-photosynthetic organisms had δ13C values within this range. CO2 released by acid treatment from coral, shell and cone carbonates had δ13C values between + 3.9 and - 2.70,. The results with photosynthetic tissue generally are interpreted in comparison to terrestrial plants as showing a major assimilation of CO2 into organic compounds via ribulosebisphosphate carboxylase in the marine ecosystem. However, a few photosynthetic organisms exhibited δ13C values between - 5.10, and - 110, and could be assimilating CO2 via phosphoenolpyruvate carboxylase. A unified scheme is presented for the pathway of carbon assimilation in the reef from the sea water through both autotrophic and heterotrophic metabolism, and finally to calcification.

Nitrogen Fixation by Blue-green Algae of the Lizard Island Area of the Great Barrier Reef

1976 ◽  
Vol 3 (1) ◽  
pp. 41 ◽  
Author(s):  
RH Burris
Keyword(s):  
Great Barrier Reef ◽  
Green Algae ◽  
Rock Surface ◽  
Barrier Reef ◽  
Fixed Nitrogen ◽  
Blue Green Algae ◽  
Average Ratio ◽  
Island Area ◽  
Partial Pressures ◽  
Lizard Island

Reduction of acetylene and 15N2 by blue-green algae and other organisms from the Lizard Island area of the Great Barrier Reef was measured. The effects of storage of the algae, the partial pressures of acetylene and oxygen, and light intensity were studied. The average ratio of acetylene to N2 reduced was 1.9. With this factor, it was calculated that 6.8 - 30.6 kg nitrogen was fixed annually per hectare of rock surface in the intertidal zone. Fixation of nitrogen by blue-green algae can contribute a substantial portion of the fixed nitrogen required for maintaining the flora and fauna of the coral reef community.

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