Search results for "Fish"
showing 10 items of 3164 documents
Meiofauna as indicator for assessing the impact of fish farming at exposed marine site
2012
This study aimed to detect the impact of organic loads due to biodeposition from a fish farm in an exposed area of the Strait of Sicily, Mediterranean Sea. Sediment chemistry and meiofaunal assemblages were investigated on a seasonal basis at four stations: two from the impacted area and two control stations. The presence of the cages induced a significant accumulation of proteins, lipids and biopolymeric carbon, resulting in a reduction in meiofaunal density at the impacted stations. Changes in community structure were also evident, as meiofauna under the cages were characterized by increased importance of polychaetes and copepods in comparison with a much lower importance of gastrotrichs …
Benthic microbial indicators of fish farm impact in a coastal area of the Tyrrhenian Sea
2004
Abstract We studied the impact of organic loads due to the biodeposition of a fish farm in a non-impacted coastal area of the Tyrrhenian Sea (Western Mediterranean). Sediment chemistry and benthic microbial community were investigated from July 1997 to February 1998 on monthly basis at two stations: one was located under the fish farm, while the second was about 1 km away, and served as a reference site. The presence of the cage induced rapid changes in the benthic conditions: the sediments were rapidly (after 6 weeks) reduced. A significant accumulation of biopolymeric carbon was observed beneath the cage both 2 weeks after the initial cage deployment, on non-impacted sediments, and 5-7 mo…
Effects of parent material on soil erosion within Mediterranean new vineyard plantations
2018
[EN] Parent material can determine specific physical and chemical soil properties and, therefore, soil erosion rates. However, for new vine plantations, there is not enough research on soil erosion assessment on different parent materials which could be helpful for agricultural management plans. The main aim of this research was to quantify soil erosion rates of two recent vineyard plantations under similar climate and land use management conditions, but on different parent materials, namely colluvium (2 years old) and marls (8 years old), located within the Les Alcusses valley vineyards in Eastern Spain. To achieve this goal, the ISUM (improved stock unearthing method) was applied. ISUM in…
The Contrasted Impact of Land Abandonment on Soil Erosion in Mediterranean Agriculture Fields
2018
Abstract Abandonment of agricultural land results in on- and off-site consequences for the ecosystem. In this study, 105 rainfall simulations were carried out in agriculture lands of the Mediterranean belt in Spain (vineyards in Malaga, almond orchards in Murcia, and orange and olive orchards in Valencia) and in paired abandoned lands to assess the impact of land abandonment on soil and water losses. After abandonment, soil detachment decreased drastically in the olive and orange orchards, while vineyards did not show any difference and almond orchards registered higher erosion rates after the abandonment. Terraced orchards of oranges and olives recovered a dense vegetation cover after the …
Diet of Phycis blennoides (Gadidae) in Relation to Fish Size and Season in the Western Mediterranean (Spain)
2002
. Despite its commercial value, little is known about the feeding ecology of the greater forkbeard, Phycis blennoides (Brunnich 1768). The stomach contents of 2631 greater forkbeard were taken at monthly intervals off the coast of the Gulf of Valencia (western Mediterranean). They were examined in order to assess the diet and to determine the fish size- and season-related dietary variation of the species. Prey items were identified to the lowest taxonomic level possible. The basic food consisted of epibenthic species, mostly Decapoda, Mysidacea and Teleostei. A change in food composition based on fish size was observed and seasonal variation in diet was also recorded. The food overlap analy…
DESCRIPTION AND MORPHOMETRICAL VARIABILITY OF A NEW SPECIES OF LIGOPHORUS AND OF LIGOPHORUS CHABAUDI (MONOGENEA: DACTYLOGYRIDAE) ON MUGIL CEPHALUS (T…
2006
A comparative morphological study of specimens of Ligophorus spp. from Mugil cephalus in western Mediterranean and the Black Sea localities has been carried out, indicating the presence of 2 distinct forms, i.e., Ligophorus chabaudi and Ligophorus cephali n. sp. A detailed description of the latter and an up-to-date redescription of L. chabaudi are provided. The existence of these 2 morphological species was additionally supported by principal component analysis based on 19 metric characters of 87 specimens arranged in samples defined by parasite species and geographical locality. The analysis indicated consistent differences between species but not between localities; this pattern was well…
Understanding myxozoan infection dynamics in the sea: Seasonality and transmission of Ceratomyxa puntazzi
2013
Abstract Ceratomyxa puntazzi affects the sharpsnout seabream, Diplodus puntazzo , a recently explored aquaculture species in the Mediterranean. Little is known about the transmission and seasonality of marine myxozoans, although this knowledge is of considerable importance for the design of management strategies for aquaculture. In the present study on C. puntazzi we investigated the potential pathways of transmission as well as the parasite abundance in fish and its density in environmental water samples, throughout a full year. We performed monthly sentinel fish exposures in a C. puntazzi enzootic environment and quantified waterborne stages in seawater. Two novel C. puntazzi -specific PC…
Stable C and N isotope concentration in several tissues of the loggerhead sea turtle Caretta caretta from the western Mediterranean and dietary impli…
2007
CONCENTRACIÓN DE ISÓTOPOS ESTABLES DE C Y N EN VARIOS TEJIDOS DE LA TORTUGA BOBA CARETTA CARETTA DEL MEDITERRÁNEO OCCIDENTAL E IMPLICACIONES SOBRE LA DIETA. – La concentración isotópica de escudos del caparazón, piel, músculo y sangre de tortuga boba (Caretta caretta) fueron analizados para investigar el patrón de variación entre tejidos y para evaluar la posición de esta especie en las redes tróficas de la cuenca Argelina. La piel presentaba valores más altos de δ13C que el músculo o los escudos del caparazón y éstos presentaban valores más altos que la sangre. En cambio, el músculo presentaba valores más altos de δ15N que la piel, ésta valores más altos que la sangre y ésta valores más al…
Soil Erosion as an Environmental Concern in Vineyards. The Case Study of Celler del Roure, Eastern Spain, by Means of Rainfall Simulation Experiments
2018
Soil erosion in vineyards is considered as an environmental concern as it depletes soil fertility and causes damage in the fields and downstream. High soil and water losses decrease soil quality, and subsequently, this can reduce the quality of the grapes and wine. However, in specialized journals of viticulture and enology, soil erosion studies are not present. This paper surveys the soil erosion losses in the vineyards of Celler del Roure, Eastern Spain, as an example of Mediterranean vineyards. We applied rainfall simulation experiments (10 plots) using a small portable rainfall simulator and 55 mm h−1 in one hour to characterize soil erodibility, runoff discharge, and soil erosion…
Notes on the Biology and Ecology of Opeatogenys gracilis (Canestrini 1864) (Pisces: Gobiesocidae) from Coastal Environments in Sicily (Mediterranean)
2001
A particularly large number of specimens of the Mediterranean coastal fish Opeatogenys gracilis (Canestrini 1864) (Pisces: Gobiesocidae) were collected from Posidonia oceanica mats of the “Stagnone di Marsala” sound (western Sicily) and in the Gulf of Carini (northern Sicily). A study was made of biometric and meristic characters and, for the first time for this species, diet composition. The biometric and meristic data did not distinguish between specimens from the two study sites. In accordance with its benthic habit, O. gracilis feeds on small phytal prey living on Posidonia oceanica leaves. The preferential food items throughout the year were Copepoda Harpacticoida.