Coral community composition and carbonate production in an urbanized seascape

Functional integrity on coral reefs is strongly dependent upon coral cover and coral carbonate production rate being sufficient to maintain three-dimensional reef structures. Increasing environmental and anthropogenic pressures in recent decades have reduced the cover of key reef-building species, producing a shift towards the relative dominance of more stress-tolerant taxa and leading to a reduction in the physical functional integrity. Understanding how changes in coral community composition influence the potential of reefs to maintain their physical reef functioning is a priority for their conservation and management. Here, we evaluate how coral communities have changed in the northern sector of the Mexican Caribbean between 1985 and 2016, and the implications for the maintenance of physical reef functions in the back- and fore-reef zones. We used the cover of coral species to explore changes in four morpho-functional groups, coral community composition, coral community calcification, the reef functional index and the reef carbonate budget. Over a period of 31 years, ecological homogenization occurred between the two reef zones mostly due to a reduction in the cover of framework-building branching ( Acropora spp.) and foliose-digitiform ( Porites porites and Agaricia tenuifolia ) coral species in the back-reef, and a relative increase in non-framework species in the fore-reef ( Agaricia agaricites and Porites astreoides ). This resulted in a significant decrease in the physical functionality of the back-reef zone. At present, both reef zones have negative carbonate budgets, and thus limited capacity to sustain reef accretion, compromising the existing reef structure and its future capacity to provide habitat and environmental services.

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Changing dynamics of Caribbean reef carbonate budgets: emergence of reef bioeroders as critical controls on present and future reef growth potential

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2014.2018 ◽

2014 ◽

Vol 281 (1796) ◽

pp. 20142018 ◽

Cited By ~ 54

Author(s):

Chris T. Perry ◽

Gary N. Murphy ◽

Paul S. Kench ◽

Evan N. Edinger ◽

Scott G. Smithers ◽

...

Keyword(s):

Coral Cover ◽

Coral Community ◽

Growth Potential ◽

Reef Growth ◽

Carbonate Production ◽

Erosion Rates ◽

Caribbean Reef ◽

Carbonate Budget ◽

Coral Recovery ◽

Fundamental Shift

Coral cover has declined rapidly on Caribbean reefs since the early 1980s, reducing carbonate production and reef growth. Using a cross-regional dataset, we show that widespread reductions in bioerosion rates—a key carbonate cycling process—have accompanied carbonate production declines. Bioerosion by parrotfish, urchins, endolithic sponges and microendoliths collectively averages 2 G (where G = kg CaCO 3 m −2 yr −1 ) (range 0.96–3.67 G). This rate is at least 75% lower than that reported from Caribbean reefs prior to their shift towards their present degraded state. Despite chronic overfishing, parrotfish are the dominant bioeroders, but erosion rates are reduced from averages of approximately 4 to 1.6 G. Urchin erosion rates have declined further and are functionally irrelevant to bioerosion on most reefs. These changes demonstrate a fundamental shift in Caribbean reef carbonate budget dynamics. To-date, reduced bioerosion rates have partially offset carbonate production declines, limiting the extent to which more widespread transitions to negative budget states have occurred. However, given the poor prognosis for coral recovery in the Caribbean and reported shifts to coral community states dominated by slower calcifying taxa, a continued transition from production to bioerosion-controlled budget states, which will increasingly threaten reef growth, is predicted.

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Citizen scientists highlight conservation value of a small subtropical reef, Flinders Reef, southeast Queensland, Australia

10.1101/602631 ◽

2019 ◽

Author(s):

Monique G.G. Grol ◽

Julie Vercelloni ◽

Tania M. Kenyon ◽

Elisa Bayraktarov ◽

Cedric P. van den Berg ◽

...

Keyword(s):

Citizen Science ◽

Community Composition ◽

Environmental Changes ◽

Coral Cover ◽

Ecological Status ◽

Coral Community ◽

Benthic Habitat ◽

Ecological Data ◽

Moreton Bay ◽

Marine Park

AbstractSubtropical reefs are unique ecosystems that require effective management – informed by regular ecological monitoring – to foster resilience to environmental changes. Resources to conduct monitoring are limited, and citizen science can complement data from local management agencies. Here, citizen science efforts document the ecological status of a subtropical reef, Flinders Reef, Moreton Bay Marine Park, Australia. Ecological surveys, following Reef Check Australia and CoralWatch protocols, were conducted by 44 trained volunteers. Ten sites at Flinders Reef were surveyed at 5-10 m depth in autumn and spring. Additionally, underwater photos and depth surveys were integrated with satellite imagery to create a detailed habitat map. Coral cover across sites ranged between 14% and 67%. Branching corals dominated the site with 67% cover and showed 89% dissimilarity in coral community composition compared to other sites. Coral community composition was mostly explained by spatial variation, of which 16% was influenced by wave exposure. Observed reef impacts including physical damage, unknown scars and coral disease were three times lower than studies on more accessible reefs in Moreton Bay Marine Park. Invertebrate abundance was relatively low (6.65 individuals per 100 m2), with the most abundant groups observed being sea urchins (Diademaspp.), gastropods (Drupellaspp.) and anemones. Butterflyfish were recorded at every site and were the most abundant fish group surveyed. Findings highlight the healthy condition of Flinders Reef, likely influenced by its offshore location and protection status as a ‘no-take’ zone. This study demonstrates that increasing the current 500m radius protection zone by a further 500m could double the protected area of coral, offering potential further conservation benefits. The findings resulting from the ecological data analysis and created benthic habitat map, provide an example of how citizen science based projects can assist marine park authorities and the public in ongoing conservation efforts.

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Coral community composition and reef development at the Similan Islands, Andaman Sea, in response to strong environmental variations

Marine Ecology Progress Series ◽

10.3354/meps09682 ◽

2012 ◽

Vol 456 ◽

pp. 113-126 ◽

Cited By ~ 27

Author(s):

GM Schmidt ◽

N Phongsuwan ◽

C Jantzen ◽

C Roder ◽

S Khokiattiwong ◽

...

Keyword(s):

Community Composition ◽

Coral Community ◽

Andaman Sea ◽

Reef Development ◽

Environmental Variations

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Assessment Assessment of benthic and coral community structure in an inshore reef in Balok, Pahang, Malaysia

Biodiversitas Journal of Biological Diversity ◽

10.13057/biodiv/d200335 ◽

2019 ◽

Vol 20 (3) ◽

pp. 872-877 ◽

Cited By ~ 1

Author(s):

MUHAMMAD FAIZ MOHD HANAPIAH ◽

SHAHBUDIN SAAD ◽

ZUHAIRI AHMAD ◽

MUHAMMAD HAMIZAN YUSOF ◽

MOHD FIKRI AKMAL KHODZORI

Keyword(s):

Community Structure ◽

Community Composition ◽

Benthic Community ◽

Coral Cover ◽

Water Environment ◽

Coral Community ◽

Marine Park ◽

Inshore Reef ◽

Class 1 ◽

Challenging Environment

Abstract. Hanapiah MFM, Saad S, Ahmad Z, Yusof MH, Khodzori MFA. Assessment of benthic and coral community structure in an inshore reef in Balok, Pahang, Malaysia. Biodiversitas 20: 872-877. Inshore water reef closer to human activities are often neglected since they are not protected by marine park management. Little is known on how this reef responses to challenging environment in terms of abundance, diversity and benthic community composition. This study provides a quantitative assessment on the benthic community composition at 5 reef sites in Balok, Pahang, Malaysia and observed the ecological adaptation in the reef community towards turbid water environment. Balok reef has 39% overall coral cover with very low macroalgae abundance (4%). A total of 28 coral genera from 12 families have been recorded with Porites the most dominant genus in the coral assemblages. Most reef sites in Balok are categorized under conservation class 1 (CC1), which indicated that resilient and survival of the reef rely on stress-tolerators taxa. The data presented here showed that Balok reef is highly resilient towards constant exposure to high sedimentation and wave action.

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The influence of micro-topography and external bioerosion on coral-reef-building organisms: recruitment, community composition and carbonate production over time

Coral Reefs ◽

10.1007/s00338-017-1650-1 ◽

2018 ◽

Vol 37 (1) ◽

pp. 227-237 ◽

Cited By ~ 7

Author(s):

Jennie Mallela

Keyword(s):

Coral Reef ◽

Community Composition ◽

Carbonate Production ◽

Micro Topography ◽

Over Time

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Cross-Shelf Variation in Coral Community Response to Disturbance on the Great Barrier Reef

Diversity ◽

10.3390/d11030038 ◽

2019 ◽

Vol 11 (3) ◽

pp. 38 ◽

Cited By ~ 7

Author(s):

Camille Mellin ◽

Angus Thompson ◽

Michelle J. Jonker ◽

Michael J. Emslie

Keyword(s):

Great Barrier Reef ◽

Community Composition ◽

Community Dynamics ◽

Coral Cover ◽

Light Attenuation ◽

Coral Community ◽

Community Response ◽

Outer Shelf ◽

Barrier Reef ◽

Chronic Stressors

Changes in coral reef health and status are commonly reported using hard coral cover, however such changes may also lead to substantial shifts in coral community composition. Here we assess the extent to which coral communities departed from their pre-disturbance composition following disturbance (disassembly), and reassembled during recovery (reassembly) along an environmental gradient across the continental shelf on Australia’s Great Barrier Reef. We show that for similar differences in coral cover, both disassembly and reassembly were greater on inshore reefs than mid- or outer-shelf reefs. This pattern was mostly explained by spatial variation in the pre-disturbance community composition, of which 28% was associated with chronic stressors related to water quality (e.g., light attenuation, concentrations of suspended sediments and chlorophyll). Tropical cyclones exacerbated the magnitude of community disassembly, but did not vary significantly among shelf positions. On the outer shelf, the main indicator taxa (tabulate Acropora) were mostly responsible for community dissimilarity, whereas contribution to dissimilarity was distributed across many taxa on the inner shelf. Our results highlight that community dynamics are not well captured by aggregated indices such as coral cover alone, and that the response of ecological communities to disturbance depends on their composition and exposure to chronic stressors.

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Community composition and size structure of murid rodents in relation to the biogeography of the Japanese archipelago

Ecography ◽

10.1034/j.1600-0587.2000.230404.x ◽

2000 ◽

Vol 23 (4) ◽

pp. 413-423 ◽

Cited By ~ 6

Author(s):

Virginie Millien-Parra ◽

Michel Loreau

Keyword(s):

Community Composition ◽

Size Structure ◽

Japanese Archipelago ◽

Murid Rodents ◽

The Japanese Archipelago

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Temporal dynamics of mycorrhizal fungal communities and co-associations with grassland plant communities following experimental manipulation of rainfall

10.32942/osf.io/t82ug ◽

2019 ◽

Cited By ~ 1

Author(s):

Coline Deveautour ◽

Sally Power ◽

Kirk Barnett ◽

Raul Ochoa-Hueso ◽

Suzanne Donn ◽

...

Keyword(s):

Community Composition ◽

Plant Community ◽

Plant Communities ◽

Fungal Community ◽

Mycorrhizal Fungi ◽

Temporal Dynamics ◽

Arbuscular Mycorrhizal ◽

Fungal Communities ◽

Plant Responses ◽

Rainfall Regimes

Climate models project overall a reduction in rainfall amounts and shifts in the timing of rainfall events in mid-latitudes and sub-tropical dry regions, which threatens the productivity and diversity of grasslands. Arbuscular mycorrhizal fungi may help plants to cope with expected changes but may also be impacted by changing rainfall, either via the direct effects of low soil moisture on survival and function or indirectly via changes in the plant community. In an Australian mesic grassland (former pasture) system, we characterised plant and arbuscular mycorrhizal (AM) fungal communities every six months for nearly four years to two altered rainfall regimes: i) ambient, ii) rainfall reduced by 50% relative to ambient over the entire year and iii) total summer rainfall exclusion. Using Illumina sequencing, we assessed the response of AM fungal communities sampled from contrasting rainfall treatments and evaluated whether variation in AM fungal communities was associated with variation in plant community richness and composition. We found that rainfall reduction influenced the fungal communities, with the nature of the response depending on the type of manipulation, but that consistent results were only observed after more than two years of rainfall manipulation. We observed significant co-associations between plant and AM fungal communities on multiple dates. Predictive co-correspondence analyses indicated more support for the hypothesis that fungal community composition influenced plant community composition than vice versa. However, we found no evidence that altered rainfall regimes were leading to distinct co-associations between plants and AM fungi. Overall, our results provide evidence that grassland plant communities are intricately tied to variation in AM fungal communities. However, in this system, plant responses to climate change may not be directly related to impacts of altered rainfall regimes on AM fungal communities. Our study shows that AM fungal communities respond to changes in rainfall but that this effect was not immediate. The AM fungal community may influence the composition of the plant community. However, our results suggest that plant responses to altered rainfall regimes at our site may not be resulting via changes in the AM fungal communities.

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