This study reports the first well‐replicated analysis of continuous coral growth records from war... more This study reports the first well‐replicated analysis of continuous coral growth records from warmer water reefs (mean annual sea surface temperatures (SST) >28.5 °C) around the Thai–Malay Peninsula in Southeast Asia. Based on analyses of 70 colonies sampled from 15 reefs within six locations, region‐wide declines in coral calcification rate (ca. 18.6%), linear extension rate (ca. 15.4%) and skeletal bulk density (ca. 3.9%) were observed over a 31‐year period from 1980 to 2010. Decreases in calcification and linear extension rates were observed at five of the six locations and ranged from ca. 17.2–21.6% and ca. 11.4–19.6%, respectively, whereas decline in skeletal bulk density was a consequence of significant reductions at only two locations (ca. 6.9% and 10.7%). A significant link between region‐wide growth rates and average annual SST was found, and Porites spp. demonstrated a high thermal threshold of ca. 29.4 °C before calcification rates declined. Responses at individual loc...
In stony corals it is often observed that specimens collected from a sheltered growth site have m... more In stony corals it is often observed that specimens collected from a sheltered growth site have more open and more thinly branched growth forms than specimens of the same species from more exposed growth sites, where stronger water currents are found. This effect was explained using a computational model of heterotrophic coral growth (Kaandorp & Sloot, 2001). In this model, growth occurs by the stepwise addition of growth layers. The local thickness of these layers depends on the availability of nutrients that are transported ...
KNAW Narcis. Back to search results. Publication Modelling and simulation of reactivity, diffusio... more KNAW Narcis. Back to search results. Publication Modelling and simulation of reactivity, diffusion, and flow in... (1996). Pagina-navigatie: Main. ...
Abstract A hybrid method is presented for simulating diffusion limited growth in three dimensions... more Abstract A hybrid method is presented for simulating diffusion limited growth in three dimensions. The computional bottleneck in sequential simulations of this type of growth process is to solve the Laplace equation in three dimensions, which descibes the diffusion process in a steady state. In the hybrid method the computational bottleneck is removed by solving the Laplace equation on a parallel platform. The results of the parallel solver are passed to a sequential program and are used in determining the growth velocities in the ...
B iologists traditionally use back-of-the- envelope, arrow-and-box-type concep- tual models of bi... more B iologists traditionally use back-of-the- envelope, arrow-and-box-type concep- tual models of biological growth and form mechanisms to develop hypothe- ses and design experiments. Following the intro- duction of experimental, high- ...
The coral‐algal symbiosis is the biological engine that drives one of the most spectacular struct... more The coral‐algal symbiosis is the biological engine that drives one of the most spectacular structures on Earth: the coral reef. Here, living coral microhabitats are engineered using 3D bioprinting, as biomimetic model system of the coral‐algal symbiosis. Various bioinks for the encapsulation of coral photosymbiotic microalgae (Breviolum psygmophilum) are developed and coral mass transfer phenomena are mimicked by 3D bioprinting coral tissue and skeleton microscale features. At the tissue–seawater interface, the biomimetic coral polyp and connective tissue structures successfully replicate the natural build‐up of the O2 diffusive boundary layer. Inside the bioprinted construct, coral‐like microscale gastric cavities are engineered using a multi‐material bioprinting process. Underneath the tissue, the constructs mimic the porous architecture of the coral aragonite skeleton at the micrometer scale, which can be manipulated to assess the effects of skeletal architecture on stress‐relate...
Additional file 1: Table SI1. The origin of thalloid liverworts Riccardia collections. Table SI2.... more Additional file 1: Table SI1. The origin of thalloid liverworts Riccardia collections. Table SI2. The number of Riccardia samples from different locations. Table SI3. P-value of Shapiro-Wilks normality test of each morphological variable among the four groups. Table SI4. Summary of ANOVA result of each morphological variable among all samples.
Observed expression domains of genes with in situ hybridizations stored for multiple stages of em... more Observed expression domains of genes with in situ hybridizations stored for multiple stages of embryonic development. The pattern descriptions are ordered in a Microsoft Access database spreadsheet. Shorthand notations: base = base of tentacle; cells = individual cells; syphonoglyph = syphonoglyph side; tuft = apical tuft; wall = body wall. "N/A" means no hybridization image and description are currently provided for this developmental stage. "?" means an entry in the expression summary is provided without a corresponding hybridization image. "none" means no gene expression is observed. "band" means expression is observed in a ring between the oral and aboral ends. "full" means expression is observed in the complete tissue layer. "biradial" means two disconnected expression domains are observed on opposite sides (suggesting a biradially symmetric pattern). "octoradial?" means expression is observed in eight separa...
ncreasing research effort on marine calcifying organisms is important and urgent, given the proje... more ncreasing research effort on marine calcifying organisms is important and urgent, given the projected CO2-driven ocean acidification for the coming century. Here we assess the growth and population dynamics of the Mediterranean endemic zooxanthellate solitary coral Balanophyllia europaea at three sites along a natural pCO2 gradient of the volcanic vents off Panarea Island (Italy). B. europaea was the only scleractinian found along the gradient. The age-length relationships obtained for each site by dating corals by means of computerized tomography resulted homogeneous, then a general age-length relationship was calculated. Growth parameters (linear extension rate, bulk skeletal density, and net calcification rate) were obtained for each site. While linear extension rate did not vary with pCO2, bulk skeletal density and net calcification rate decreased with increasing pCO2. At each site, the age structure was obtained, and several observed and theoretical demographic parameters were derived (age structure stability, istantaneous rate of mortality, average age, % of immature individuals, age at maximum biomass, average age of biomass) and compared among sites. The results are discussed in relation to the envisaged ocean acidification scenario
Atmospheric carbon dioxide enrichment alters seawater carbonate chemistry, thus threatening calci... more Atmospheric carbon dioxide enrichment alters seawater carbonate chemistry, thus threatening calcifying organisms such as corals. Coral populations at carbon dioxide vents are natural acidification experiments that mimic organism responses to seawater pH values projected for 2100. Even if demographic traits are paramount information to assess ecological relationships and habitat suitability, population dynamics studies on corals thriving under acidified conditions are lacking. Here, we investigate the demography and reproduction of populations of the solitary, symbiotic, temperate coral Balanophyllia europaea naturally living along a pH gradient at a Mediterranean CO2 vent. Gametogenesis and larval production were unaffected while recruitment efficiency collapsed at low and variable pH, contributing to coral abundance decline and suggesting that life stages between larval release and early polyp growth are hindered by acidification. Exploring these processes is crucial to assess cora...
This study reports the first well‐replicated analysis of continuous coral growth records from war... more This study reports the first well‐replicated analysis of continuous coral growth records from warmer water reefs (mean annual sea surface temperatures (SST) >28.5 °C) around the Thai–Malay Peninsula in Southeast Asia. Based on analyses of 70 colonies sampled from 15 reefs within six locations, region‐wide declines in coral calcification rate (ca. 18.6%), linear extension rate (ca. 15.4%) and skeletal bulk density (ca. 3.9%) were observed over a 31‐year period from 1980 to 2010. Decreases in calcification and linear extension rates were observed at five of the six locations and ranged from ca. 17.2–21.6% and ca. 11.4–19.6%, respectively, whereas decline in skeletal bulk density was a consequence of significant reductions at only two locations (ca. 6.9% and 10.7%). A significant link between region‐wide growth rates and average annual SST was found, and Porites spp. demonstrated a high thermal threshold of ca. 29.4 °C before calcification rates declined. Responses at individual loc...
In stony corals it is often observed that specimens collected from a sheltered growth site have m... more In stony corals it is often observed that specimens collected from a sheltered growth site have more open and more thinly branched growth forms than specimens of the same species from more exposed growth sites, where stronger water currents are found. This effect was explained using a computational model of heterotrophic coral growth (Kaandorp & Sloot, 2001). In this model, growth occurs by the stepwise addition of growth layers. The local thickness of these layers depends on the availability of nutrients that are transported ...
KNAW Narcis. Back to search results. Publication Modelling and simulation of reactivity, diffusio... more KNAW Narcis. Back to search results. Publication Modelling and simulation of reactivity, diffusion, and flow in... (1996). Pagina-navigatie: Main. ...
Abstract A hybrid method is presented for simulating diffusion limited growth in three dimensions... more Abstract A hybrid method is presented for simulating diffusion limited growth in three dimensions. The computional bottleneck in sequential simulations of this type of growth process is to solve the Laplace equation in three dimensions, which descibes the diffusion process in a steady state. In the hybrid method the computational bottleneck is removed by solving the Laplace equation on a parallel platform. The results of the parallel solver are passed to a sequential program and are used in determining the growth velocities in the ...
B iologists traditionally use back-of-the- envelope, arrow-and-box-type concep- tual models of bi... more B iologists traditionally use back-of-the- envelope, arrow-and-box-type concep- tual models of biological growth and form mechanisms to develop hypothe- ses and design experiments. Following the intro- duction of experimental, high- ...
The coral‐algal symbiosis is the biological engine that drives one of the most spectacular struct... more The coral‐algal symbiosis is the biological engine that drives one of the most spectacular structures on Earth: the coral reef. Here, living coral microhabitats are engineered using 3D bioprinting, as biomimetic model system of the coral‐algal symbiosis. Various bioinks for the encapsulation of coral photosymbiotic microalgae (Breviolum psygmophilum) are developed and coral mass transfer phenomena are mimicked by 3D bioprinting coral tissue and skeleton microscale features. At the tissue–seawater interface, the biomimetic coral polyp and connective tissue structures successfully replicate the natural build‐up of the O2 diffusive boundary layer. Inside the bioprinted construct, coral‐like microscale gastric cavities are engineered using a multi‐material bioprinting process. Underneath the tissue, the constructs mimic the porous architecture of the coral aragonite skeleton at the micrometer scale, which can be manipulated to assess the effects of skeletal architecture on stress‐relate...
Additional file 1: Table SI1. The origin of thalloid liverworts Riccardia collections. Table SI2.... more Additional file 1: Table SI1. The origin of thalloid liverworts Riccardia collections. Table SI2. The number of Riccardia samples from different locations. Table SI3. P-value of Shapiro-Wilks normality test of each morphological variable among the four groups. Table SI4. Summary of ANOVA result of each morphological variable among all samples.
Observed expression domains of genes with in situ hybridizations stored for multiple stages of em... more Observed expression domains of genes with in situ hybridizations stored for multiple stages of embryonic development. The pattern descriptions are ordered in a Microsoft Access database spreadsheet. Shorthand notations: base = base of tentacle; cells = individual cells; syphonoglyph = syphonoglyph side; tuft = apical tuft; wall = body wall. "N/A" means no hybridization image and description are currently provided for this developmental stage. "?" means an entry in the expression summary is provided without a corresponding hybridization image. "none" means no gene expression is observed. "band" means expression is observed in a ring between the oral and aboral ends. "full" means expression is observed in the complete tissue layer. "biradial" means two disconnected expression domains are observed on opposite sides (suggesting a biradially symmetric pattern). "octoradial?" means expression is observed in eight separa...
ncreasing research effort on marine calcifying organisms is important and urgent, given the proje... more ncreasing research effort on marine calcifying organisms is important and urgent, given the projected CO2-driven ocean acidification for the coming century. Here we assess the growth and population dynamics of the Mediterranean endemic zooxanthellate solitary coral Balanophyllia europaea at three sites along a natural pCO2 gradient of the volcanic vents off Panarea Island (Italy). B. europaea was the only scleractinian found along the gradient. The age-length relationships obtained for each site by dating corals by means of computerized tomography resulted homogeneous, then a general age-length relationship was calculated. Growth parameters (linear extension rate, bulk skeletal density, and net calcification rate) were obtained for each site. While linear extension rate did not vary with pCO2, bulk skeletal density and net calcification rate decreased with increasing pCO2. At each site, the age structure was obtained, and several observed and theoretical demographic parameters were derived (age structure stability, istantaneous rate of mortality, average age, % of immature individuals, age at maximum biomass, average age of biomass) and compared among sites. The results are discussed in relation to the envisaged ocean acidification scenario
Atmospheric carbon dioxide enrichment alters seawater carbonate chemistry, thus threatening calci... more Atmospheric carbon dioxide enrichment alters seawater carbonate chemistry, thus threatening calcifying organisms such as corals. Coral populations at carbon dioxide vents are natural acidification experiments that mimic organism responses to seawater pH values projected for 2100. Even if demographic traits are paramount information to assess ecological relationships and habitat suitability, population dynamics studies on corals thriving under acidified conditions are lacking. Here, we investigate the demography and reproduction of populations of the solitary, symbiotic, temperate coral Balanophyllia europaea naturally living along a pH gradient at a Mediterranean CO2 vent. Gametogenesis and larval production were unaffected while recruitment efficiency collapsed at low and variable pH, contributing to coral abundance decline and suggesting that life stages between larval release and early polyp growth are hindered by acidification. Exploring these processes is crucial to assess cora...
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