Search results for "coral"
showing 10 items of 239 documents
Many More Consumers Not Always Induce Stronger Competition: Weaker Interspecific Competition Despite Higher Species Richness in Secondary Feeding Gui…
2021
The species functional structuration (specifically in terms of species richness and average intensity of interspecific competition) is widely varying among species communities and this point is now very well documented in literature. But, what about the species functional structuration within the different feeding guilds that coexist in a same local community – in particular the primary and the secondary feeding guilds? Are there significant differences – or not – between them in this respect? This rather fundamental issue does not seem having been addressed yet, at least using appropriate investigative tools. However, a series of recently published case studies, precisely implementing such…
South China Sea or West Philippine Sea?
2017
The South China Sea (“West Philippine Sea”) has been for several years a space of potential conflict between several countries due to overlapping of their EEZs and China’s claim of a large part of this oceanic space, well beyond its UN-endorsed EEZ. The Spratly islets and Scarborough shoal are mere coral reefs, uninhabited for the most part, but they lie in the middle of rich fishing grounds and atop large reserves of petroleum and natural gas. Furthermore, the area is one of the world’s busiest sea lanes for commercial navigation. This chapter presents the general rules of UNCLOS (international laws pertaining to oceanic space), and then examines the competing claims, focusing on the China…
Growth impacts in a changing ocean: insights from two coral reef fishes in an extreme environment
2020
AbstractDetermining the life history consequences for fishes living in extreme and variable environments will be vital in predicting the likely impacts of ongoing climate change on reef fish demography. Here, we compare size-at-age and maximum body size of two common reef fish species (Lutjanus ehrenbergiiandPomacanthus maculosus) between the environmentally extreme Arabian/Persian Gulf (‘Arabian Gulf’) and adjacent comparably benign Oman Sea. Additionally, we use otolith increment width profiles to investigate the influence of temperature, salinity and productivity on the individual growth rates. Individuals of both species showed smaller size-at-age and lower maximum size in the Arabian G…
The influence of thermal extremes on coral reef fish behaviour in the Persian Gulf
2019
AbstractDespite increasing environmental variability within marine ecosystems, little is known about how coral reef fish species will cope with future climate scenarios. The Arabian/Persian Gulf is an extreme environment, providing an opportunity to study fish behaviour on reefs with seasonal temperature ranges which include both values above the mortality threshold of Indo-Pacific reef fish, and values below the optimum temperature for growth. Summer temperatures in the Gulf are comparable to those predicted for the tropical ocean by 2090-2099. Using field observations in winter, spring and summer, and laboratory experiments, we examined the foraging activity, distance from refugia and res…
Nutrients attenuate the negative effect of ocean acidification on reef coral calcification in the Arabian Sea upwelling zone (Masirah Island, Oman)
2021
Tropical shallow-water reefs are the most diverse ecosystem in the ocean. Its persistence rests upon adequate calcification rates of the reef building biota, such as reef corals. Optimum calcification rates of reef corals occur in oligotrophic environments with high seawater saturation states of aragonite (Ωsw), which leads to increased vulnerability to anthropogenic ocean acidification and eutrophication. The calcification response of reef corals to this changing environment is largely unknown, however. Here, we present annually and sub-annually resolved records of calcification rates (n = 3) of the coral Porites from the nutrient rich and low Ωsw Arabian Sea upwe…
Persentase Tutupan Terumbu Karang di Perairan Pasir Putih Kabupaten Manokwari
2017
Penelitian ini dilakukan pada bulan Oktober sampai November 2014 di perairan Pasir Putih Kabupaten Manokwari, berlokasi di Pantai Air Salobar. Tujuan penelitian adalah untuk mengetahui persentase tutupan terumbu karang, kualitas fisik-kimia air dan korelasi kualitas fisik-kimia air terhadap persentase tutupan terumbu karang di bagian barat daya perairan Pasir Putih, Manokwari. Metode yang digunakan untuk memperoleh data persentase tutupan karang adalah Point Intercept Transect (PIT) pada kedalaman 3 m (Transek I), 7 m (Transek II) dan 10 m (Transek III). Hasil pengamatan diperoleh persentase tutupan karang pada Transek I adalah 91%, Transek II adalah 78% dan Transek III adalah 54%. Kondisi …
New species of the rugose coral genus Lithostrotion Fleming in the upper Viséan from the Azrou-Khenifra Basin (Morocco)
2020
The new species Lithostrotion termieri Rodríguez & Somerville is described. It shows very large corallites of the rugose genus Lithostrotion Fleming. It has been recorded up to now only in upper Viséan rocks from the type locality, the Akrab ridge, Morocco also called Tizi Ben Zizouit by Termier & Termier (1950), who identified it as Lonsdaleia floriformis, and south-east from Tabainout, also from the Azrou-Khenifra Basin.
Coral growth bands: A new and easy to use paleothermometer in paleoenvironment analysis and paleoceanography (late Miocene, Greece)
2006
[1] Modern scleractinian corals are classical components of marine shallow warm water ecosystems. Their occurrence and diversity patterns in the geological record have been widely used to infer past climates and environmental conditions. Coral skeletal composition data reflecting the nature of the coral environment are often affected by diagenetic alteration. Ghost structures of annual growth rhythms are, however, often well preserved in the transformed skeleton. We show that these relicts represent a valuable source of information on growth conditions of fossil corals. Annual growth bands were measured in massive hemispherical Porites of late Miocene age from the island of Crete (Greece) t…
Freshwater discharge and sediment dispersal — Control on growth, ecological structure and geometry of Late Miocene shallow-water coral ecosystems (ea…
2007
Abstract Insolation-driven oceanographic changes are well documented in the Mediterranean deep-sea record and reflect episodes of high precipitation and/or freshwater discharge. In the shallow-water record, however, changes in relative sea-level and sea surface temperature are usually regarded as prime controls on Miocene coral reefs, whereas pulses of freshwater influx represent a hitherto unrecognized factor influencing their growth, ecological structure and geometry. On the island of Crete (NW Messara Basin, Greece) early Tortonian coral biostromes occur associated with deltas along the basin margin and rimming islands formed by large uplifted tectonic blocks. In turbid delta environment…
Interspecific-Competition Strongly Constrains Species-Richness and Species-Abundance Evenness in a Tropical Marine Molluscan Community Inhabiting Cau…
2021
Increasing species-richness at the local scale (within species communities) is accommodated, first, by the diversification of the niches respectively associated to species. Yet, in case of excessive supply in colonizing species issued from the regional pool, the corresponding increase in the number of solicited niches may lead to some “niche-overcrowding” resulting in significant niche-overlaps. Then, second, strong interspecific competition for shared resource can arise, triggered by the density in individuals among those species co-occurring at niche-overlaps. Accordingly, the accommodation of species-richness within a local community involves a balance between (i) the positive contributi…