A review of bottom-up vs. top-down control of sponges on Caribbean fore-reefs: what’s old, what’s new, and future directions

PeerJ, Journal Year: 2018, Volume and Issue: 6, P. e4343 - e4343

Published: Jan. 31, 2018

Interest in the ecology of sponges on coral reefs has grown recent years with mounting evidence that are becoming dominant members reef communities, particularly Caribbean. New estimates water column processing by sponge pumping activities combined discoveries related to carbon and nutrient cycling have led novel hypotheses about role ecosystem function. Among these developments, a debate emerged relative effects bottom-up (food availability) top-down (predation) control community Caribbean fore-reefs. In this review, we evaluate impact latest findings debate, as well provide new insights based older citations. Recent studies employed different research methods demonstrated dissolved organic (DOC) detritus principal sources food for growing list species, challenging idea availability living picoplankton is sole proxy growth or abundance. reports confirmed earlier macroalgae release labile DOC available nutrition. Evidence structure fish predation further supported gut content historical population hawksbill turtles, which likely had much greater abundances past. Implicit investigations designed address vs. appropriate fore-reef environments, where benthic communities relatively homogeneous terrestrial influences abiotic minimized. One study test both aspects did so using experiments conducted entirely shallow lagoonal habitats dominated mangroves seagrass beds. The results from reinterpreted supporting past demonstrating predator preferences species abundant habitats, but grazed away habitats. We conclude fore-reefs present largely structured predation, offer directions research, such determining environmental conditions under may be food-limited (e.g., deep sea, habitats) monitoring changes populations turtles rebound.

Language: Английский

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Influence of Water Masses on the Biodiversity and Biogeography of Deep-Sea Benthic Ecosystems in the North Atlantic

Frontiers in Marine Science, Journal Year: 2020, Volume and Issue: 7

Published: April 21, 2020

Circulation patterns in the North Atlantic Ocean have changed and re-organized multiple times over millions of years, influencing biodiversity, distribution connectivity deep-sea species ecosystems. In this study, we review effects water mass properties (temperature, salinity, food supply, carbonate chemistry oxygen) on benthic megafauna (from to community level) discussed future scenarios climate change. We focus key oceanic controls biodiversity biogeography patterns. place particular attention cold-water corals sponges, as these are ecosystem-engineering organisms that constitute vulnerable marine ecosystems with high associated biodiversity. Besides documenting current state knowledge topic, a scenario for deep basin was predicted. The pace severity change will vary across regions. However, predicted showed all regions be exposed stressors by 2100, experiencing at least one critical temperature (+2°C), organic carbon fluxes (reduced up 50 %), ocean acidification (pH reduced 0.3), aragonite saturation horizon (shoaling above 1000 m) and/or reduction dissolved oxygen (5%). northernmost suffer greatest impacts. Warmer more acidic oceans drastically reduce suitable habitat ecosystem-engineers, severe consequences such declines population densities, even compromising their long-term survival, loss biogeographic might compromise large scales. These can aggravated reductions fluxes, particularly areas where availability is already limited. Declines biomass diminish ecosystem services provision, nutrient cycling, etc. This study shows affected contemporary anthropogenic impacts ongoing unlikely withstand additional pressures from intrusive human activities. serves also warning protect through regulations tempering socio-political drivers increasing exploitation resources.

Language: Английский

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Microbially mediated nutrient cycles in marine sponges

FEMS Microbiology Ecology, Journal Year: 2019, Volume and Issue: 95(11)

Published: Oct. 4, 2019

Efficient nutrient cycles mediated by symbiotic microorganisms with their hosts are vital to support the high productivity of coral reef ecosystems. In these ecosystems, marine sponges important habitat-forming organisms in benthic community and harbor abundant microbial symbionts. However, few studies have reviewed critical microbially cycling processes sponges. To bridge this gap, review article, we summarize existing knowledge recent advances understanding carbon (C), nitrogen (N), phosphorus (P) sulfur (S) sponges, propose a conceptual model that describes potential interactions constraints major cycles, suggest shifting redox state induced animal behavior like sponge pumping can exert great influence on activities communities. Constraints include lack spatial temporal variations host behavior; more needed areas. Sponge microbiomes may significant impact world's

Language: Английский

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Climate change alterations to ecosystem dominance: how might sponge‐dominated reefs function?

Ecology, Journal Year: 2018, Volume and Issue: 99(9), P. 1920 - 1931

Published: July 10, 2018

Anthropogenic stressors are impacting ecological systems across the world. Of particular concern recent rapid changes occurring in coral reef systems. With ongoing degradation from both local and global stressors, future reefs likely to function differently current coral-dominated ecosystems. Determining key attributes of states is critical reliably predict outcomes for ecosystem service provision. Here we explore impacts changing sponge dominance on reefs. Qualitative modelling futures suggests that due increased abundance will have different other trophic levels compared with as a result declining abundance. By exploring uncertainty model identify need (1) quantify carbon flow through sponges, (2) determine importance food limitation (3) assess ubiquity recently described "sponge loop," (4) competitive relationships between sponges benthic taxa, particularly algae, (5) understand how organisms alters pathways energy flows Addressing these knowledge gaps facilitate development more complex models functional sponge-dominated

Language: Английский

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Differential processing of dissolved and particulate organic matter by deep-sea sponges and their microbial symbionts

Scientific Reports, Journal Year: 2020, Volume and Issue: 10(1)

Published: Oct. 15, 2020

Deep-sea sponges create hotspots of biodiversity and biological activity in the otherwise barren deep-sea. However, it remains elusive how sponge hosts their microbial symbionts acquire process food these food-limited environments. Therefore, we traced processing (i.e. assimilation respiration) 13C- 15N-enriched dissolved organic matter (DOM) bacteria by three dominant North Atlantic deep-sea sponges: high abundance (HMA) demosponge Geodia barretti, low (LMA) Hymedesmia paupertas, LMA hexactinellid Vazella pourtalesii. We also assessed both sources into sponge- bacteria-specific phospholipid-derived fatty acid (PLFA) biomarkers. All were capable assimilating DOM as well bacteria. two differed considerably between tested species: assimilation-to-respiration efficiency was highest for HMA sponge, yet uptake rates 4-5 times lower compared to sponges. In contrast, assimilated most efficiently at rate demosponges. Our results indicate that phylogeny functional traits (e.g., symbionts, morphology) influence preferences diet composition sponges, which further helps understand role key ecosystem engineers habitats.

Language: Английский

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