Limits...
Self-generated morphology in lagoon reefs.

Blakeway D, Hamblin MG - PeerJ (2015)

Bottom Line: In these situations reef morphology can be considered a phenotype of the predominant reef building organism.The capacity to infer coral type from reef morphology can potentially be used to identify and map specific coral habitat in remotely sensed images.More generally, identifying ecological mechanisms underlying other examples of self-generated reef morphology can potentially improve our understanding of present-day reef ecology, because any ecological process capable of shaping a reef will almost invariably be an important process in real time on the living reef.

View Article: PubMed Central - HTML - PubMed

Affiliation: School of Earth and Environment, University of Western Australia , Crawley , Western Australia, Australia.

ABSTRACT
The three-dimensional form of a coral reef develops through interactions and feedbacks between its constituent organisms and their environment. Reef morphology therefore contains a potential wealth of ecological information, accessible if the relationships between morphology and ecology can be decoded. Traditionally, reef morphology has been attributed to external controls such as substrate topography or hydrodynamic influences. Little is known about inherent reef morphology in the absence of external control. Here we use reef growth simulations, based on observations in the cellular reefs of Western Australia's Houtman Abrolhos Islands, to show that reef morphology is fundamentally determined by the mechanical behaviour of the reef-building organisms themselves-specifically their tendency to either remain in place or to collapse. Reef-building organisms that tend to remain in place, such as massive and encrusting corals or coralline algae, produce nodular reefs, whereas those that tend to collapse, such as branching Acropora, produce cellular reefs. The purest reef growth forms arise in sheltered lagoons dominated by a single type of reef builder, as in the branching Acropora-dominated lagoons of the Abrolhos. In these situations reef morphology can be considered a phenotype of the predominant reef building organism. The capacity to infer coral type from reef morphology can potentially be used to identify and map specific coral habitat in remotely sensed images. More generally, identifying ecological mechanisms underlying other examples of self-generated reef morphology can potentially improve our understanding of present-day reef ecology, because any ecological process capable of shaping a reef will almost invariably be an important process in real time on the living reef.

No MeSH data available.


Related in: MedlinePlus

Influence of colonisation density and timing on model reef morphology.These plan view images show the effects of decreasing the recruitment rate from the default 0.25% to 0.125% (A: branching Acropora reef, 100 iterations), (B: basic reef, 80 iterations), increasing the recruitment rateto 1% (C: branching Acropora reef, 90 iterations, D: basic reef, 60 iterations), and periodically adding new recruits during reef growth (E: branching Acropora reef, 100 iterations, F: basic reef, 70 iterations).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4499466&req=5

fig-14: Influence of colonisation density and timing on model reef morphology.These plan view images show the effects of decreasing the recruitment rate from the default 0.25% to 0.125% (A: branching Acropora reef, 100 iterations), (B: basic reef, 80 iterations), increasing the recruitment rateto 1% (C: branching Acropora reef, 90 iterations, D: basic reef, 60 iterations), and periodically adding new recruits during reef growth (E: branching Acropora reef, 100 iterations, F: basic reef, 70 iterations).

Mentions: Varying water depth also significantly influences reef morphology. Reducing depth reduces reef thickness, which constrains the morphological expression of the collapse limit such that the appearance of the branching Acropora reefs transforms from cellular to nodular as depth decreases (Figs. 13A and 13B). In the extreme case of reefs growing in only one or two metres water depth, where the collapse limit has no effect, all variants of the model produce identical nodular reefs. Increasing depth, by itself, has little influence on reef morphology (Figs. 13C and 13D). However, more realistic representations incorporating sea level rise and depth-dependent growth cause reef slopes to steepen significantly as depth increases (Figs. 13E and 13F). Variations in colonisation density and timing have relatively little effect on reef morphology, besides the expected crowding of patch reefs at high density (Fig. 14).


Self-generated morphology in lagoon reefs.

Blakeway D, Hamblin MG - PeerJ (2015)

Influence of colonisation density and timing on model reef morphology.These plan view images show the effects of decreasing the recruitment rate from the default 0.25% to 0.125% (A: branching Acropora reef, 100 iterations), (B: basic reef, 80 iterations), increasing the recruitment rateto 1% (C: branching Acropora reef, 90 iterations, D: basic reef, 60 iterations), and periodically adding new recruits during reef growth (E: branching Acropora reef, 100 iterations, F: basic reef, 70 iterations).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4499466&req=5

fig-14: Influence of colonisation density and timing on model reef morphology.These plan view images show the effects of decreasing the recruitment rate from the default 0.25% to 0.125% (A: branching Acropora reef, 100 iterations), (B: basic reef, 80 iterations), increasing the recruitment rateto 1% (C: branching Acropora reef, 90 iterations, D: basic reef, 60 iterations), and periodically adding new recruits during reef growth (E: branching Acropora reef, 100 iterations, F: basic reef, 70 iterations).
Mentions: Varying water depth also significantly influences reef morphology. Reducing depth reduces reef thickness, which constrains the morphological expression of the collapse limit such that the appearance of the branching Acropora reefs transforms from cellular to nodular as depth decreases (Figs. 13A and 13B). In the extreme case of reefs growing in only one or two metres water depth, where the collapse limit has no effect, all variants of the model produce identical nodular reefs. Increasing depth, by itself, has little influence on reef morphology (Figs. 13C and 13D). However, more realistic representations incorporating sea level rise and depth-dependent growth cause reef slopes to steepen significantly as depth increases (Figs. 13E and 13F). Variations in colonisation density and timing have relatively little effect on reef morphology, besides the expected crowding of patch reefs at high density (Fig. 14).

Bottom Line: In these situations reef morphology can be considered a phenotype of the predominant reef building organism.The capacity to infer coral type from reef morphology can potentially be used to identify and map specific coral habitat in remotely sensed images.More generally, identifying ecological mechanisms underlying other examples of self-generated reef morphology can potentially improve our understanding of present-day reef ecology, because any ecological process capable of shaping a reef will almost invariably be an important process in real time on the living reef.

View Article: PubMed Central - HTML - PubMed

Affiliation: School of Earth and Environment, University of Western Australia , Crawley , Western Australia, Australia.

ABSTRACT
The three-dimensional form of a coral reef develops through interactions and feedbacks between its constituent organisms and their environment. Reef morphology therefore contains a potential wealth of ecological information, accessible if the relationships between morphology and ecology can be decoded. Traditionally, reef morphology has been attributed to external controls such as substrate topography or hydrodynamic influences. Little is known about inherent reef morphology in the absence of external control. Here we use reef growth simulations, based on observations in the cellular reefs of Western Australia's Houtman Abrolhos Islands, to show that reef morphology is fundamentally determined by the mechanical behaviour of the reef-building organisms themselves-specifically their tendency to either remain in place or to collapse. Reef-building organisms that tend to remain in place, such as massive and encrusting corals or coralline algae, produce nodular reefs, whereas those that tend to collapse, such as branching Acropora, produce cellular reefs. The purest reef growth forms arise in sheltered lagoons dominated by a single type of reef builder, as in the branching Acropora-dominated lagoons of the Abrolhos. In these situations reef morphology can be considered a phenotype of the predominant reef building organism. The capacity to infer coral type from reef morphology can potentially be used to identify and map specific coral habitat in remotely sensed images. More generally, identifying ecological mechanisms underlying other examples of self-generated reef morphology can potentially improve our understanding of present-day reef ecology, because any ecological process capable of shaping a reef will almost invariably be an important process in real time on the living reef.

No MeSH data available.


Related in: MedlinePlus