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 (Mugil cephalus) 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 (CI) 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 (PLI) parameter. Conclusively, a regular monitoring program of heavy metal is recommended for protecting these organisms, and to reduce the environmental risks.
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Serranus cabrillaGrowth parameters Mortality Exploitation rate Mediterranean Some population parameters of the comber, Serranus cabrilla, were presented in this study. From January to December 2018, a total of 1250 samples of Serranus cabrilla (11 ≤ TL ≤ 23.9 cm, 14.34 ≤ TW ≤ 157.7 g), have been studied in the Gulf of Annaba (Eastern coasts of Algeria), based on length-frequency data. FiSAT II software was used for different analyses. The growth parameters of Von Bertalanffy are L ∞ = 24.94 cm, k = 0.38 year -1 and to = -0.45 year, with a performance of growth (φʹ) of 2.37. The total (Z) and natural (M) mortality of comber in the Annaba gulf were equal to 1.41 and 0.81 year -1 respectively, while the fishing mortality was estimated to 0.60. The exploitation rate is around 0.45 and indicates that the population of comber is lightly under exploited in the study area. The length at first capture (L c50 ) is equal to 12.04 cm.
Yield per recruit MSY Algeria This study is the first that deals with the stock status of the bogue Boops boops (Linnaeus, 1758) in the Eastern Algerian coast (Western Mediterranean). It aims is to estimate the important parameters needed to evaluate the dynamics of the stock of this species which is economically important resource in Algeria. The FiSAT II software has been used for data analysis. The total length and weight of the fishes sampled ranged from 10.1 to 30.9 cm and from 13.47 to 268.15 g, respectively. The longevity has been estimated at 5 years. The parameters of von Bertalanffy growth curve were L∞ = 32.03 cm, K = 0.28 yr-1 , t o =-1.13 years and ɸ' = 2.45. The lengthweight relationships was described by parameters a = 0.016 and b = 2.815, reflecting a trend towards negative allometric growth. The total mortality (Z), natural (M) and fishing (F) mortalities were 1.03, 0.37 and 0.66 yr-1 , respectively. The current exploitation rate (E) of the species was 0.64. The relative yield per recruit analysis (Y'/R) from the Beverton-Holt showed that the current level of exploitation is significantly higher than E max and E 0.5 (0.54 and 0.32 respectively), indicating that the population is overexploited and suffers from fishing pressure. For sustainable management of this resource, the current exploitation rate should be reduced by 50%.
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, Abramis brama. 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, A. brama, 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.
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