The study was undergone on the distribution of abundance of Patella rustica Linnaeus, 1758, with the objective of evaluating of its abundance along the rocky shores of the coast and located sites with high density. A ...The study was undergone on the distribution of abundance of Patella rustica Linnaeus, 1758, with the objective of evaluating of its abundance along the rocky shores of the coast and located sites with high density. A total of twelve sampling sites were selected along the gulf of Skikda. Each station was sampled using quadrats of 25 cm^2. In the present study, two environmental parameters were measured "in situ" in the water column at each sampling station (water surface temperature, pH). Biotic communities of the rocky shores are considered to be generally controlled by physical factors such as temperature and desiccation. Therefore, three measurements were made for each abiotic parameter during this survey and mean values were used for statistical analysis. Consequently, the data of abundance (expressed in frequency) of species were calculated based on the distributed individuals along the quadrat. P. rustica is distributed mainly in the East more than in the West particularly from SI to S5. The condition index calculated at 12 stations revealed important seasonal variations, with the maximum during summer season highlighting three stations (S2, S11 and S 12). This index is also very important in S3 and S4. The factors of pollution at these points had not affected the abundance and index condition.展开更多
文摘The study was undergone on the distribution of abundance of Patella rustica Linnaeus, 1758, with the objective of evaluating of its abundance along the rocky shores of the coast and located sites with high density. A total of twelve sampling sites were selected along the gulf of Skikda. Each station was sampled using quadrats of 25 cm^2. In the present study, two environmental parameters were measured "in situ" in the water column at each sampling station (water surface temperature, pH). Biotic communities of the rocky shores are considered to be generally controlled by physical factors such as temperature and desiccation. Therefore, three measurements were made for each abiotic parameter during this survey and mean values were used for statistical analysis. Consequently, the data of abundance (expressed in frequency) of species were calculated based on the distributed individuals along the quadrat. P. rustica is distributed mainly in the East more than in the West particularly from SI to S5. The condition index calculated at 12 stations revealed important seasonal variations, with the maximum during summer season highlighting three stations (S2, S11 and S 12). This index is also very important in S3 and S4. The factors of pollution at these points had not affected the abundance and index condition.