Latitudinal environmental gradients and diel variability influence abundance and community structure of Chaetognatha in Red Sea coral reefs

Al-Aidaroos, Ali M.; Karati, Kusum Komal; El‐Sherbiny, Mohsen M.; Devassy, Reny P.; Kürten, Benjamin

doi:10.1080/14772000.2016.1211200

Cited by 12 publications

(14 citation statements)

References 48 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Consistent with these findings, our data revealed that the GPP threshold that separated autotrophic from heterotrophic communities in the Red Sea (1.7 mmol O 2 m −3 d −1 ) is similar to that reported across oceanic communities elsewhere (Duarte and Agustí, 1998;Duarte and Regaudie-de-Gioux, 2009), agreeing with the oligotrophic characteristics that govern the basin at certain periods or locations. The latitudinal differences depicted in our results mirror the increasing north-south pattern in Chl a concentration and photosynthetic carbon fixation rates previously reported for the Red Sea (Acker et al, 2008;Raitsos et al, 2013;Qurban et al, 2014;Kheireddine et al, 2017), which are supported by the presence of different planktonic communities (Al-aidaroos et al, 2016;Pearman et al, 2016;Robitzch et al, 2016;Kheireddine et al, 2017;Kottuparambil and Agusti, 2018).…”

Section: Variability Of Plankton Community Metabolic Rates Along the supporting

confidence: 90%

Rates and drivers of Red Sea plankton community metabolism

et al. 2019

View full text Add to dashboard Cite

Abstract. Resolving the environmental drivers shaping planktonic communities is fundamental for understanding their variability, in the present and the future, across the ocean. More specifically, addressing the temperature-dependence response of planktonic communities is essential as temperature plays a key role in regulating metabolic rates and thus potentially defining the ecosystem functioning. Here we quantified plankton metabolic rates along the Red Sea, a uniquely oligotrophic and warm environment, and analysed the drivers that regulate gross primary production (GPP), community respiration (CR), and net community production (NCP). The study was conducted on six oceanographic surveys following a north–south transect along the Saudi Arabian coast. Our findings revealed that GPP and CR rates increased with increasing temperature (R2=0.41 and 0.19, respectively; p<0.001 in both cases), with a higher activation energy (Ea) for GPP (1.20±0.17 eV) than for CR (0.73±0.17 eV). The higher Ea for GPP than for CR resulted in a positive relationship between NCP and temperature. This unusual relationship is likely driven by the relatively higher nutrient availability found towards the warmer region (i.e. southern Red Sea), which favours GPP rates above the threshold that separates autotrophic from heterotrophic communities (1.7 mmol O2 m−3 d−1) in this region. Due to the arid nature, the basin lacks riverine and terrestrial inputs of organic carbon to subsidise a higher metabolic response of heterotrophic communities, thus constraining CR rates. Our study suggests that GPP increases steeply with increasing temperature in the warm ocean when relatively high nutrient inputs are present.

show abstract

Section: Variability Of Plankton Community Metabolic Rates Along the supporting

confidence: 90%

Rates and drivers of Red Sea plankton community metabolism

et al. 2019

View full text Add to dashboard Cite

show abstract

“…On the other hand, the lack of a latitudinal pattern described here for seagrasses and macroalgae aligns with the results for productivity of phytoplankton obtained in several research cruises in the Red Sea (Qurban et al, 2017), which showed no clear latitudinal patterns. Hence, whereas the South to North oligotrophication of the Red Sea affects some species of benthic invertebrates on corals reefs (Sawall et al, 2015;Al-Aidaroos et al, 2016) and to a certain extent pelagic phytoplankton Chl a concentrations (Raitsos et al, 2013;Kürten et al, 2015), it is not reflected in iron concentration, Chl a concentration or physiological performance of Red Sea macrophytes.…”

Section: Discussionmentioning

confidence: 99%

“…Similar to our results, the seagrasses Syringodium filiforme and Thalassia testudinum were described to be ironlimited in a karstic region in the Mexican Caribbean also lacking riverine inputs . In the Red Sea Basin inputs of iron are likely coming from three sources: The Indian Ocean via the Strait of Bab al Mandab, wind-induced upwelling of deep water (Triantafyllou et al, 2014;Al-Aidaroos et al, 2016), and dust deposition from the Sahara and Arabian Deserts (Jish Prakash et al, 2015). Although the quantitative sources and inputs of Fe in the Red Sea are barely known (Jish Prakash et al, 2015), our results on Fe concentration in the tissue of 17 species of macrophytes suggest that Fe is scarce and limiting in most benthic shallow ecosystems in the Arabian Red Sea, regardless of their latitudinal location.…”

Section: Discussionmentioning

confidence: 99%

Iron Deficiency in Seagrasses and Macroalgae in the Red Sea Is Unrelated to Latitude and Physiological Performance

et al. 2018

View full text Add to dashboard Cite

Iron can limit primary production in shallow marine systems, especially in tropical waters characterized by carbonated sediments, where iron is largely trapped in a non-available form. The Red Sea, an oligotrophic ecosystem characterized by a strong N-S latitudinal nutrient gradient, is a suitable setting to explore patterns in situ of iron limitation in macrophytes and their physiological performance under different iron regimes. We assessed the interactions between environmental gradients and physiological parameters of poorly-studied Red Sea macrophytes. Iron concentration, chlorophyll a concentration, blade thickness, and productivity of 17 species of macrophytes, including seven species of seagrasses and 10 species of macroalgae, were measured at 21 locations, spanning 10 latitude degrees, along the Saudi Arabian coast. Almost 90% of macrophyte species had iron concentrations below the levels indicative of iron sufficiency and more than 40% had critically low iron concentrations, suggesting that iron is a limiting factor of primary production throughout the Red Sea. We did not identify relationships between tissue iron concentration, chlorophyll a concentration and physiological performance of the 17 species of seagrass and macroalgae. There was also no latitudinal pattern in any of the parameters studied, indicating that the South to North oligotrophication of the Red Sea is not reflected in iron concentration, chlorophyll a concentration or productivity of Red Sea macrophytes.

show abstract

“…GAIW is further distinguished from GASW by higher nutrient and chlorophyll concentrations (Bethoux, ; Churchill et al, ; Ganssen & Kroon, ; Maillard & Soliman, ; Sofianos & Johns, ) and has been identified as the principal source of water‐borne nutrients to the Red Sea (Naqvi et al, ; Souvermezoglou et al, ). The subsequent northward transport and mixing of GAIW create a latitudinal gradient of productivity and biogeography in the Red Sea (Al‐Aidaroos et al, ; Halim, ; Kürten et al, ; Sofianos & Johns, ).…”

Section: Introductionmentioning

confidence: 99%

Physical Mechanisms Routing Nutrients in the Central Red Sea

et al. 2017

Self Cite

View full text Add to dashboard Cite

Mesoscale eddies and boundary currents play a key role in the upper layer circulation of the Red Sea. This study assesses the physical and biochemical characteristics of an eastern boundary current (EBC) and recurrent eddies in the central Red Sea (CRS) using a combination of in situ and satellite observations. Hydrographic surveys in November 2013 (autumn) and in April 2014 (spring) in the CRS (22.15°N–24.1°N) included a total of 39 and 27 CTD stations, respectively. In addition, high‐resolution hydrographic data were acquired in spring 2014 with a towed undulating vehicle (ScanFish). In situ measurements of salinity, temperature, chlorophyll fluorescence, colored dissolved organic matter (CDOM), and dissolved nitrate: phosphorous ratios reveal distinct water mass characteristics for the two periods. An EBC, observed in the upper 150 m of the water column during autumn, transported low‐salinity and warm water from the south toward the CRS. Patches of the low‐salinity water of southern origin tended to contain relatively high concentrations of chlorophyll and CDOM. The prominent dynamic feature observed in spring was a cyclonic/anticyclonic eddy pair. The cyclonic eddy was responsible for an upward nutrient flux into the euphotic zone. Higher chlorophyll and CDOM concentrations, and concomitant lower nitrate:phosphorous ratios indicate the influence of the EBC in the CRS at the end of the stratified summer period.

show abstract

Latitudinal environmental gradients and diel variability influence abundance and community structure of Chaetognatha in Red Sea coral reefs

Cited by 12 publications

References 48 publications

Rates and drivers of Red Sea plankton community metabolism

Rates and drivers of Red Sea plankton community metabolism

Iron Deficiency in Seagrasses and Macroalgae in the Red Sea Is Unrelated to Latitude and Physiological Performance

Physical Mechanisms Routing Nutrients in the Central Red Sea

Contact Info

Product

Resources

About