Search results for "Water current"

Über das Wesen der optomotorischen Reaktionen

1953

Flying and swimming animals need to be able to avoid passive displacement by air and water currents. Optomotor reactions essentially serve this purpose. The animals must be able to distinguish precisely between sensory stimulation caused by passive displacement and by active locomotion. Stimulation due to active movements does not release optomotor reactions. Apparent exceptions to this rule, occurring only under artificial circumstances, are caused by a derangement of either normal sensory stimulation or normal movement and, consequently, of their normal correlation. Examples of both cases are discussed.

Analysis and Prevention of Microplastics Pollution in Water: Current Perspectives and Future Directions

2019

The analysis, prevention, and removal of microplastics (MPs) pollution in water is identified as one major problem the world is currently facing. MPs can be directly released to water or formed by the degradation of bigger plastics. Nowadays, it is estimated that annually between 4 and 12 million tonnes of plastic go into the seas and oceans-with a forecast for them to outweigh the amount of fish in 2050. Based on the existing studies, the characterization of MPs in waters is still one of the remaining challenges because they can be easily confused with organic or other types of matter. Consequently, there is an urgent necessity to establish pathways for the chemical identification of the M…

Sicilian transitional waters: Current status and future development

2010

To appraise the current knowledge of Sicilian transitional waters (TWs), a review was undertaken of the information available on these ecosystems. In detail, a synthesis of the current status is reported, highlighting for each area the ecological features and status, historical data, conservation regime, environmental emergencies and anthropic pressures to which they are subject. The Sicilian TWs reviewed include coastal ponds and lakes, mires and areas with active and nonactive saltworks. Almost all of these ecosystems are affected by several protection regimes because of their high naturalistic value, although current knowledge is limited and fragmented. A few areas have received more att…

Do cilia drive water through the buccopharyngeal and opercular cavities in the fossorial Otophryne robusta tadpole?

1993

Asociaciones de Ostrácodos del Mioceno Temprano—Medio de Loma Negra (Bardenas Reales de Navarra, Cuenca del Ebro): Evolución Paleoambiental de un Med…

2014

LOWER-MIDDLE MIOCENE OSTRACOD ASSEMBLAGES OF LOMA NEGRA (BARDENAS REALES DE NAVARRA, EBRO BASIN): PALAEOENVIRONMENTAL EVOLUTION OF A LACUSTRINE SYSTEM. The palaeoenvironmental evolution of the Loma Negra section (Bardenas Reales de Navarra, Ebro Basin) during the lower-middle Miocene, is studied for the first time. The paleoen- vironmental interpretation is based on the recovered ostracod assemblages and the sedimentology. The lower part of this section is composed by red, yellow and grey mudstones, and with Paralimnocythere sp. as the most abundant ostracod taxon. The lithological features and the fau- nistic assemblage allows the interpretation of a paleoenvironment with the development o…