Search results for "Algal assemblage"
showing 2 items of 2 documents
Effects of fish-farm biodeposition on periphyton assemblages on artificial substrates in the southern Tyrrhenian Sea (Gulf of Castellammare, Sicily)
2007
An algal assemblage growing on artificial substrata of fish-farm cages was investigated. Specifically, algal response to the effects of fish-farm facilities was studied, in order to identify a possible future descriptor of biodeposition impact. Some sites were positioned upstream of the farms (at least 750 m; ‘controls’) and other sites were positioned downstream of the farms (‘impacts’). All sites were situated in the Tyrrhenian Sea. Control and impact sites differed significantly with regard to the dissolved nutrient profile. The fouling community (samples were scraped from buoys) displayed a reduction gradient in diversity which increased with the effect of fish farms. A total of 51 taxa…
Larval Development of Arbacia lixula (Linneo, 1758) in two Marine Protected Area: preliminary data.
2010
The sea urchin Arbacia lixula is a crucial species in driving the algal assemblages dynamic of the infralittoral zone. A. lixula is considered a thermophilic species and its increase in abundance in western Mediterranean waters, probably is due to an increase in seawater temperature. The aim of this study was to examine the reproductive success of A. lixula by larval development. The study was conducted within two Sicilian MPA (Capo Gallo-Isola delle Femmine and Ustica), characterized by photophilic algae, the same exposure and seawater temperature. In each area, twenty random specimens was sampled from May to September 2010, and mature gametes were collected from six males and six females …