Search results for " REE"

On the generation and degradation of emerged coral reef terrace sequences: First cosmogenic 36Cl analysis at Cape Laundi, Sumba Island (Indonesia)

2021

(IF 4.45: Q1); International audience; The emerged coral reef terrace sequence at Cape Laundi, on the north coast of Sumba Island (Indonesia), with at least 18 successive strandlines, remains poorly dated in spite of numerous previous data. The age discrepancies within these coral reef terraces (CRTs) were previously explained by their polycyclic nature, triggered by marine erosion and reoccupation of old coral colonies by new ones. This study aims at highlighting these processes, as well as the continental denudation that participates in the partial stripping of the thin superficial coral reef layer overlying the pre-existing surface, exhuming older coral colonies. For this purpose, we use…

Effects of fish feeding by snorkellers on the density and size distribution of fishes in a Mediterranean marine protected area

2005

Although there is a great deal of evidence to show that supplementary feeding by humans in terrestrial environments causes pronounced changes in the distribution and behaviour of wild animals, at present very little is known about the potential for such effects on marine fish. This study evaluated the consequences of feeding by snorkellers on fish assemblages in the no-take area of the Ustica Island marine protected area (MPA; western Mediterranean) by (1) determining if reef fish assemblage structure is affected in space and time by tourists feeding the fish; (2) assessing the effects of feeding on the abundance of the most common fish species; and (3) assessing the effects of feeding on t…

Sidney Armor Reeve: Engineer, Inventor, Progressive, and Underappreciated Utopian

2022

Sidney Armor Reeve, professional engineer and amateur historian, economist, and sociologist, writing during what has been described as the Progressive Era, at-tacked the very foundations of the existing economic and social orders. He explic-itly criticized the dominant commercialism of the capitalist society as being a can-cer, a major cause of inequality and unemployment, offering instead a program of reform that, while some reviewers characterized it as consistent with the program of the socialists, presented something of an alternative vision, one recognizing the primacy of the Ultimate Consumer. His remedy, favoring as it did the central con-trol of the economy, shared at least commonal…

Género, raza y trabajo en los almacenes de Amazon en Estados Unidos

2021

Trace element fractionation through halite crystallisation: Geochemical mechanisms and environmental implications

2019

Halite is an important mineral for industry, agriculture and food production. It crystallises after water evaporation, while the progressive growth of dissolved metal ions in brines is occurring. Then, halite exploitation may provide the delivery of metal ions in the environment and the mechanism of this trace element accumulation should be studied. In this work we investigate the distribution of lanthanides and Y (hereafter named Rare Earth Elements, REE), Zr and Hf between crystallising halite and brines in the Dead Sea as geochemical tools for recognising the mechanism of metal ion removal from brines and accumulation in halite. Halite forms cubic crystals where octahedral planes sometim…

Changes in fish communities due to benthic habitat shifts under ocean acidification conditions

2020

Ocean acidification will likely change the structure and function of coastal marine ecosystems over coming decades. Volcanic carbon dioxide seeps generate dissolved CO2 and pH gradients that provide realistic insights into the direction and magnitude of these changes. Here, we used fish and benthic community surveys to assess the spatio-temporal dynamics of fish community properties off CO2 seeps in Japan. Adding to previous evidence from ocean acidification ecosystem studies conducted elsewhere, our findings documented shifts from calcified to non-calcified habitats with reduced benthic complexity. In addition, we found that such habitat transition led to decreased diversity of associated …

Artificial Reefs in the Gulf of Castellammare (North-West Sicily): A Case Study

2000

Most of the plans for fish stock replenishment recently undertaken in Sicily have focused on the Gulf of Castellammare. Reasons for choosing this biotope for a restocking plan include the size of the Gulf (300 km2), the importance and traditional role of its fisheries and the existence of information describing the local marine environment. The Gulf of Castellammare is the widest bay in Sicily and fishing has always played a major role in the local economy. Today income from fishing complements that from tourism.

Jenis-Jenis Kima dan Kelimpahannya di Perairan Amdui Distrik Batanta Selatan Kabupaten Raja Ampat

2017

Kima merupakan salah satu jenis molusca laut yang banyak ditemukan di perairan Raja Ampat. Hewan ini dilindungi di seluruh dunia termasuk di Indonesia. Penelitian ini dilakukan pada bulan Maret-April 2014, di perairan Amdui yang memiliki ekosistem terumbu karang, dan ditetapkan 3 lokasi pengamatan yaitu: Pulau Ayem, Teluk Sawawris dan Teluk Sawros. Metode yang digunakan pada penelitian ini adalah metode observasi dengan teknik belt transek, dan bertujuan untuk mengetahui jenis dan kelimpahan kima di perairan Amdui. Kima yang ditemukan di perairan laut Kampung Amdui Kabupaten Raja Ampat yaitu 8 jenis terdiri dari T. crocea, T. maxima, T. squamosa, T .gigas, H. porcellanus, H. hippopus, T. te…

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…