Search results for "Reef"

The Use and Abuse of Sea Resources

2017

As a maritime country, the Philippines is a place of high fish consumption. Many coastal villages are populated by fishermen, who are amongst the poorest of working Filipinos. International comparisons show that the Philippine fisheries sector is mostly characterized by small inefficient fishing vessels, while some of the fishing methods are extremely destructive to the resource. Today, fishing moratoriums must be imposed in some areas to allow the reproduction of the fish. Poaching and illegal fisheries, including by foreign vessels, especially from China, plague the most important fisheries areas. Aquaculture has developed to counterbalance the decline of the natural resource, but it has …

Distribution and diversity of fish species exposed to artisanal fishery along the Sudanese Red Sea coast

2019

AbstractThe semi-enclosed Red Sea harbours one of the longest coral-reef ecosystems on the planet. The ≈ 850 km section of the western shore, comprising the coastline of the Red Sea State of the Republic of Sudan, has however been sparsely studied. Sudan’s coral reef fishery provides livelihoods to fishers and business opportunities by means of local and regional trade, however, the knowledge level of the state of the natural resources and the impacts of fisheries are poorly known. Here we report the results from the first three comprehensive fisheries research surveys spanning the entire Sudanese coast in 2012-13, representing a new baseline for the western coast fisheries resources. The s…

The genus Palaeolituonella (Foraminifer) and description of Palaeolituonella angulata nov. sp. from Upper Triassic reef limestones of the Tethys

2009

A new marker for sea surface temperature trend during the last centuries in temperate areas: Vermetid reef

2004

The presence of Vermetid reefs in temperate waters, their diffusion in the Mediterranean Sea, and the possibility of performing 14 C ages allowed the use of Vermetids as an indicator of sea level changes. We present new data on sea climate trend fluctuations that could be interpreted as Sea Surface Temperature (SST) variations, recorded on Vermetid (Dendropoma petraeum) reefs, by means of isotopic analysis. The isotopic records show positive values of the d 18 O relative to present-day values in the period between 1600 and 1850 AD; this deviation occurs in association with the climatic cooling event known as Little Ice Age (LIA). Subsequently, we can observe the warming trend that character…

Relazione tra le densità di Dendropoma petraeum e la microtopografia del reef a vermeti”

2011

Ocean acidification and elevated temperature negatively affect recruitment, oxygen consumption and calcification of the reef-building Dendropoma cris…

2019

Expected temperature rise and seawater pH decrease may affect marine organism fitness. By a transplant experiment involving air-temperature manipulation along a natural CO2 gradient, we investigated the effects of high pCO(2) (similar to 1100 mu atm) and elevated temperature (up to +2 degrees C than ambient conditions) on the reproductive success, recruitment, growth, shell chemical composition and oxygen consumption of the early life stages of the intertidal reef-building vermetid Dendropoma cristatum. Reproductive success was predominantly affected by temperature increase, with encapsulated embryos exhibiting higher survival in control than elevated temperature conditions, which were in t…

Can Sex Inversion Be Environmentally Induced?

1980

Among teleosts simultaneous hermaphroditism and spontaneous sex inversion (either protogyny or protandry) occur in many families that inhabit tropical and subtropical marine waters. The tooth-carp Rivulus marmoratus is unique among these in being self-fertilizing. Most studies are descriptive work on gonad histology and reproductive behavior. Experimental investigations are scanty and do not yet provide fruitful ideas that might help to understand what is occurring in a fish when it changes sex. Behavioral observations and experiments led to the hypothesis that in certain coral reef fish sex inversion may be under social control. The term sex inversion requires closer examination in order t…

Shelled-Molluscs Fauna at Abrolhos Bank (Brazil): Assessment of Both Total Species Richness and the Completed Distribution of Species Frequencies by …

2020

Numerous anthropogenic threats to the exceptionally rich coral-reef ecosystem at Abrolhos Bank (Brazil) arguably require implementing drastic conservation policy and meanwhile, urge for the prior detailed assessment of species richness and the species distribution across the Bank. Due to their unavoidable incompleteness, the already implemented “Rapid Assessment Surveys” at Abrolhos Bank deserve being completed, at least numerically, by implementing an appropriate extrapolation procedure, to avoid serious bias precisely due to ignoring both the number and the frequency distribution of those species still remaining undetected after Rapid Assessment Surveys. Complying with this concern, I rep…

Paleoclimatic control of biogeographic and sedimentary events in Tethyan and peri-Tethyan areas during the Oxfordian (Late Jurassic)

2005

International audience; The paleobiogeographical distribution of Oxfordian ammonites and coral reefs in northern and Central Europe, the Mediterranean area, North and East Africa, and the Middle East and Central Asia is compared with the distribution in time and space of the most important lithofacies. Interest in the Oxfordian is focused on changes in facies and in biogeographical patterns that can be interpreted as the results of climatic events. Paleotemperature trends inferred from oxygen isotopes and paleoclimatic simulations are tested against fossil and facies data. A Late Callovian–Early Oxfordian crisis in carbonate production is indicated by the widespread absence of Lower Oxfordi…

Late Messinian to Early Pliocene paleoenvironmental changes in the Melilla Basin (NE Morocco) and their relation to Mediterranean evolution

2003

Abstract Three major paleoenvironmental changes have been recognized during the late Miocene to Early Pliocene in the Melilla Basin (Northeastern Morocco) and compared with the regional events that affected the Mediterranean hydrology during this crucial period. The first change was the definitive conversion of the restricted marine conditions that prevailed since the end of the reef carbonate complex into lacustrine environments; this occurred around 5.8 Ma which is earlier than in the rest of the Mediterranean where the Lower Evaporites were still forming. These lacustrine settings display great similarities with the Lago-Mare environments that started in the Mediterranean during the depo…