The present work was designed to assess the contamination level in the coastal of Annaba, following the spectrophotometric determination of the level of some metallic elements (Fe, Cu, Pb, Zn, Ni and ...Cd) in the sediments along an increasing bathymetric gradient (10 m and 20 m), as well as in the biological indicator grey mullet (
) muscle. During the winter period (2014), 12 surface sediment samples, and a total of 24 fish were collected. Once the samples are dried, crushed and sieved, 0.5 g dry weight of each sample was added to concentrated acids. The results showed that the levels of some metals are superior to the recommended guideline values, and consequently the sediment of this bay is contaminated by iron, lead and copper. The contamination index (
) showed a general tendency in the concentration of the studied metals as follows: Fe > Pb > Cu > Zn > Ni > Cd, since the most studied metals occurred at higher concentration in depth (20 m).
However, the average concentrations of metals in fishes were found to be as the following order: Fe > Zn > Pb > Cu > Ni > Cd. The consumption of fish from some contaminated sites can be dangerous because concentrations of lead, cadmium and zinc exceed the international standards. Moreover, the strong positive correlation observed between the metallic elements of sediments and fishes confirm that these metals resulted from the similar sources of the anthropic activities, such as domestic, port, industrial and agricultural waste discharges. This is confirmed by the determined of pollution load index (
) parameter. Conclusively, a regular monitoring program of heavy metal is recommended for protecting these organisms, and to reduce the environmental risks.
The diet of the greater forkbeard
(Brünnich, 1768) of the Algerian coast was studied between December 2013 and June 2015, providing information on its ecology for a better understanding of the ...feeding strategy. A total of 956 individuals, whose total length (TL) varied between 9.7 and 54.5 cm and weight (W) between 2.80 and 1334.11 g, were examined. The index of relative importance (%IRI), combining the three main descriptors of the presence of different ingested prey (%F, %N, %W), was used to characterize the relative importance of different food taxa. Qualitative and quantitative variations in diet were studied according to sex, size and seasons. The average annual digestive vacuity index (%V) was 5.51. It did not vary between seasons (x
= 5.43, x
= 7.82, α = 5%) and size (x
= 2.08, x
= 5.99, α = 5%), but was different between male (%V = 4.94) and female (%V= 12.78). Qualitative analysis of stomach contents reveals a fairly diverse range of predation with 1342 preys counted for a total weight of 462.84 g, which corresponds to an average number (AN) and weight (AW) of 3.03 and 1.04 g, respectively. This species feeds on benthic preys, composed mainly of natantia crustaceans (%IRI = 44.84) and teleost fish (%IRI = 2.61) with intraspecific preys (%IRI = 6.15). This cannibalism was frequent in specimens with a TL that exceeds 20 cm; it was even more frequent in females as well as in winter. Significant differences in feeding habits of
occurred according to sex, fish size and between seasons. The trophic level (TROPH) was high (3.66 < TROPH < 3.97), corresponding to carnivorous character.
The Gulf of Skikda is subject to a large influx of effluent discharges from the industrial zone "Sonatrach" and wastewater from the city, resulting in heavy pollution of the sea by metallic trace ...elements (MTE).This study aims to determine the bioaccumulation of heavy metals in the muscle of salema Sarpa salpa from gulf of Skikda in the eastern part of the Algerian coast. Elements such as Cd, Pb, Cu, and Zn were assayed using Atomic Absorption Spectrophotometry. The distribution of TME in sediments and fish shows a significant spatiotemporal fluctuation. In muscle, the seasonal variation is related to the physiological state of the fish. Cd and Pb concentrations were above the prescribed levels. The analyzes carried out made it possible to identify the samples of the Mollo station as the most contaminated ones. Indeed, the contamination of S. salpa tissues reflects the contamination of the site. Mean concentrations in sediments followed the sequence Zn > Pb > Cu > Cd and in muscles Pb > Zn > Cu> Cd, respectively and this, whatever the season. A significant difference was noticed in the level of TME in the two compartments (ANOVA, p<0.001).
This study was conducted in Hammam Debagh Reservoir located in northeastern Algeria, which was first the subject of fish farming tests in 2001. The species tested included Chinese carp, royal carp, ...common carp, pikeperch, and common bream. The present work aimed to determine the age and growth of one of the most frequently caught species in the reservoir, common bream,
. This information is essential to the knowledge of fish biology, and thereby to solving many of the problems of fish research and development. A sample of 100 common bream,
, was caught with gillnets over a period of six months from December 2017 to May 2018. The results obtained fit well with the growth model and were similar to those published regarding other environments. Scales from a sample of 50 fish were read under an optical microscope, which permitted identifying five age groups. The value of the overall sex ratio (4.88) revealed a strong imbalance in favor of males throughout the study period. The relationship linking length-weight is of the minor allometry type with b < 3.
U razdoblju od prosinca 2013. do lipnja 2015. istraživan je sastav ishrane tabinje bjelice Phycis blennoides (Brünnich, 1768) na obali Alžira pružajući informaciju o ekologiji vrste te pridonoseći ...boljem razumijevanju strategije njenog hranjenja. Analizirano je ukupno 956 primjeraka čija je totalna dužina (TL) varirala između 9,7 i 54,5 cm i mase (W) između 2,80 i 1334,11 g. Za obilježavanje relativne važnosti različitih taksona u progutanoj hrani, korišten je indeks relativne važnosti (%IRI) kombinirajući tri glavna deskriptora prisustva različitog progutanog plijena. Kvalitativne i kvantitativne varijacije u ishrani proučavane su prema spolu, veličini i godišnjim dobima. Prosječni godišnji indeks praznine crijeva (% V) je bio 5,51. Nije varirao između sezona (χ²cal = 5,43, χ²th = 7,82, α = 5%) i veličine (χ²cal = 2.08, χ²th = 5,99, α = 5%), ali je bio različit između mužjaka (%V = 4,94) i ženki (%V= 12,78). Kvalitativna analiza sadržaja želudca otkriva prilično raznolik raspon predacije s izbrojana 1342 plijena ukupne mase 462,84 g što odgovara prosječnom broju (AN) i masi (AW) od 3,03 odnosno 1,04 g. Ova vrsta se hrani bentoskim plijenom, uglavnom sastavljenim od rakova plivača (natantia) (% IRI = 44,84) i riba košunjača (% IRI = 2,61) te s intraspecifičnim plijenom (% IRI = 6,15). Ova pojava kanibalizma je česta kod primjeraka s TL koja premašuje 20 cm a još je češća kod ženki u zimskom periodu. Značajne razlike u prehrambenim navikama P. blennoides javljaju se prema spolu, veličini ribe i godišnjim dobima. Trofička razina (TROPH) bila je visoka (3.66 <TROPH <3.97), što odgovara karnivornom karakteru vrste.
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