Kavala Gulf Research Articles

Age and growth of round sardinella (<i>Sardinella aurita</i>) in the northeastern Mediterranean

The round sardinella, Sardinella aurita Valenciennes, 1847, was sampled monthly from commercial purse-seine vessels in Kavala Gulf (northern Aegean Sea, Greece) for two complete year cycles (September 2000-August 2002). Its maximum total length and age were 248 mm and 5 years respectively. The length-weight relationship was W=0.0062TL 3.064 for males and W=0.0059TL 3.084 for females. The marginal increment analysis on scales (n=1352) confirmed annulus formation during February-March, which coincided with the lowest sea surface temperature prevailing in the study area. The marginal increment ratio for ages 1, 2 and 3 was positively correlated with sea surface temperature (all r >0.4, P ? =248.678 mm, K=0.509 yr -1 and t 0 =-0.881 yr. The comparison of growth parameters for round sardinella, using the auximetric plot, from Mediterranean and northwest African waters indicated different growth patterns between the two areas.

Biodiversity of zoobenthic hard-substrate sublittoral communities in the Eastern Mediterranean (North Aegean Sea)

The spatial dispersion of zoobenthos from sublittoral hard substrate communities in the northern part of the Aegean Sea has been studied during summer 1997 and 1998. Material was collected by SCUBA diving, by totally scraping off five replicate quadrates (400 cm 2 each) at three depth levels (15, 30, 40 m) from six sites located in Chalkidiki peninsula, plus one in Kavala Gulf. The examination of the 19,343 living specimens collected revealed the presence of 314 species. Though the multivariate analyses showed high similarity between stations, the structure of this sciaphilic algal community seems to have an increased spatial heterogeneity. Four distinct facies were recorded in accordance with the occurrence of different algal forms, the degree of hard substrate inclination and the water clarity. A short review on the biodiversity of sublittoral communities in the Mediterranean revealed the affinity between the western and the eastern basin and also among the photophilic and the sciaphilic algal communities.

Infra‐ and Circalittoral Soft Substratum Macrofaunal Assemblages of Kavala Gulf (Aegean Sea)

AbstractFive macrobenthic assemblages of the infralittoral and circalittoral zones located in the Gulf of Kavala, North Aegean, are described: (i) the assemblage of gravely sand with Parvicardium roseum and Clausinella brogniartii, (ii) the assemblage of sandy silt with Loripes lacteus and Nephthys hombergii. (iii) the clayey silt assemblage with Terebellides stroemi and Sternaspis scutata, (iv) the sandy silt assemblage with Amphiura chiajei and (v) the assemblage of silt with Labioleanira yhleni, the latter being described for the first time. Their composition is statistically tested, discussed in relation to abiotic factors, and compared with that of the corresponding assemblages from the Aegean and other Mediterranean and Atlantic areas.

Cd and Zn uptake in macrophyceae from Greek coasts

In the frame of a project financed by the General Secretariat of Research and Technology, the Institute of Botany has undertaken to measure the degree of pollution in the marine area by means of physicochemical and biotic parameters. Bioaccumulation of heavy metals in the macrophyceae has also been examined. Since the latter are immobile, they form strong indicators of pollution for the respective biotopes. Comparing the measurements carried out in marine macrophyceae obtained from the Gulf of Kavala and Pylos, we have made the following conclusions. Seasonal variations were detected in the Cd and Zn content of nine marine macrophyceae species which had already been investigated. Cadmium, one of the toxic metals, was, in certain cases, present in a large number of species. Fluctuations in the quantities were seasonally detected, but more obvious differences were those between species from different classes of macrophyceae. In contrast, the amount of Zn was generally lower. When we compared the values of Zn to those of Cd in the same algal species, we detected an antagonism between them (i.e. higher values for Cd were accompanied by lower values for Zn). Finally, on comparing the biotopes, we found there was slightly more Cd in Pylos than in Kavala. In the harbour of Kavala, in particular, where there is strong evidence of domestic sewage, the amount of Cd is very low. It is well known that Cd is derived mostly from industrial waste waters; in the city of Kavala, the domestic waste does not include high quantities of heavy toxic metals.

Preliminary environmental study of New Karvali Bay (Kavala Gulf, North Greece)

Abstract In this presentation the results of an environmental study of New Karvali bay, in Kavala Gulf, North Greece, are announced. In the studied bay the main industrial activity is a Factory of Chemical Fertilizers (FCF) and its wastes have been discharged, practically without any treatment, to the sea. The study has shown that the concentrations of phosphates and nitrates in the area around the place of the waste ejection from the factory are relatively high. Other remarkable points of the study are the presence of fluoride anions in higher level than normal and the low concentration of heavy metals (Cu, Pb and Zn).

Pb accumulation in macrophyceae off the coasts of Kavala (Aegean Sea) and of pylos (Ionian Sea), Greece

Abstract Marine environmental pollution has been considered by all human social classes to be a problem of major importance. Comparing measurements carried out in marine macrophyceae derived from the Gulf of Kavala and Pylos we have concluded the following, the element Pb having been taken into account. Seasonal variations are detected in the Pb content of the macrophyceae species examined. Pb, which is regarded as one of the most toxic metals, is not encountered in great quantities in these biotopes. The Pb content in the algae of the harbour of Kavala is higher than in the other two stations (Palio, Kavala and Pylos).