On the Methods for the Delimitation of Seasons

It is well known that air pollution is one of the major factors affecting human health and the activities in a town. Among the various air pollutants an interesting one, especially for sunny climates, is the reactive O₃. O₃ varies significantly through the year; it is therefore very important to know the onset and the duration of the warm period of the year since at that time O₃ concentrations increase significantly. In this work, an attempt was made to determine the onset of warm season of the year as well as its duration in various sites located in Northeastern Mediterranean. For this purpose, a fuzzy clustering method is used. The method was applied on the isobaric thickness between 1000 and 500 hPa for the period from 1974 to 1997. The results were compared to conventional methods based on synoptic classification and were found to be in good agreement.     

Factors affecting the spawning period of sardine in two highly oligotrophic Seas

Ovarian histology and weight dynamics of reproductive and somatic tissues were used to investigate seasonality of spawning and factors affecting reproductive period in two E Mediterranean sardine, Sardina pilchardus, populations (central Aegean and Ionian Seas), between September 1999 and May 2001. Despite similarities in the general spawning pattern of the two populations, i.e. protracted spawning season during the colder months of the year, reproductive period in the Ionian was shorter and lagged behind the Aegean by 2–3 months. In both Seas, reproductive period was influenced by body size as smaller females tended to have both shorter and delayed spawning season. Whereas hepatosomatic index (HSI) was consistently higher in reproductively active females during the whole spawning period, seasonality of spawning did not match variations of HSI. In both Seas fluctuations of HSI matched the spring burst of primary productivity and were followed by fluctuations in somatic condition and mesenteric fat by a 2 months’ lag. Somatic condition and reproductive activity displayed inverse seasonal patterns, implying that egg production in sardine basically relies on visceral and muscular fat deposits, accumulated during the summer growing season. Reliance of egg production on past energetic reserves suggests that sardine is a capital breeder, which is a rather efficient strategy in such oligotrophic habitats as the E Mediterranean, where winter spawning is accompanied by a particular decline in adult preying fields.     

Toxic Properties of Metals and Organotin Compounds and Their Interactions on Daphnia magna and Vibrio fischeri

In the present study toxicity tests were performed in order to determine the toxic properties of four organotin compounds and three heavy metals and to examine the interactive effects of binary metal mixtures on two different test species: the freshwater crustacean Daphnia magna and the marine bacterium Vibrio fischeri. D. magna proved to be more sensitive to metals than V. fischeri. Tributyltin chloride and copper were found to be the most toxic substances on both test organisms. The interactive effects between trimethyltin chloride/copper and trimethyltin/chromium on both test species were investigated and synergistic, additive and antagonistic actions were observed.     

Marginalised social groups in contemporary weee management within social enterprises investments: A study in Greece

This paper deals with the creation of appropriate conditions aimed at developing social services for reuse and recycling of waste electrical and electronic equipment (WEEE), by the inclusion of handicapped and Roma people in the workforce. Application areas for the project are the Hellenic (Greek) regions of Thessaly and North Aegean, where these groups suffer from professional and social exclusion. The efforts to reduce unemployment in the two aforementioned groups, together with the efforts to implement related Greek and European legislation for sustainable WEEE management, are examined here. Furthermore, networking and cooperation at local, regional and central levels between small enterprises, entrepreneurships and local authorities are examined, so that these social enterprises and their corresponding investments may support the development of the Greek alternative WEEE recycling system.     

Environmental Toxicity Assessment: state of the art and future directions in a world of arising threats

Environmental Science and Pollution Research -     

Preface

Water, Air, &; Soil Pollution: Focus -     

Chemical and ecotoxicological assessment of sludge-based biosolids used for corn field fertilization

Environmental Science and Pollution Research - Sludge-based biosolids can be used for crop fertilization and for soil enrichment with organic matter. The prerequisites for their application are...     

The effect of coagulation on the toxicity and mutagenicity of reclaimed municipal effluents

The objectives of this work were the assessment of the effectiveness of coagulation on the reclamation of secondary effluents and the evaluation of the quality of reclaimed waters by the examination of their ecotoxic and mutagenic properties. Aluminum coagulants resulted in higher removal of organic content, than iron coagulant, reaching up to 40%; the removal of heavy metals, such as zinc and copper was enhanced by the addition of a low strength anionic flocculant. The toxicity of pre-concentrated samples to the bacteria Vibrio fischerii was related to the heavy metal content, especially zinc and copper, indicating the significance of the metals bioavailability and their potential interactive effects. The secondary effluents exhibited mutagenic effects on strain TA 98; these effects were increased during coagulation with ferric chloride (both in absence and presence of flocculant). However, the addition of aluminum coagulants resulted in a decrease of mutagenic potential of secondary effluents, due to the extended removal of organic matter.