Toilet training shows differences among cultures. The age of initiation may be increased as the parents are educated better and a child-orientated approach becomes more popular than the parent-orientated approach.
Abstract:The Black Sea receives large quantities of unregulated and uncontrolled fresh water with drawl for irrigation purposes, hydro and thermal power generation and the use of coastal areas for permanent human settlements; shipping; and untreated domestic, industrial and agricultural wastes drain into the sea via the rivers or directly. In spite of this, research on the heavy metal pollution in marine biota of the Black Sea is limited.This review prepared to be informed of the urban sewage pollution loads and heavy metal concentrations of Turkish coasts of Black Sea. The urban sewages and heavy metals currently effective in Turkey coasts of the Black Sea so as to bring up the levels of land based sources of pollution with rivers and streams in the sea. The Black Sea has a special importance because of its being a sea that receives two large rivers, Kizilirmak and Yesilirmak and in this investigation we can show that Yesilirmak has higher amount of discharge then other rivers. This investigation was carried out with indicate to determine the aid of land-based sources and marine activities to the Black Sea, bringing up its present state.Total chrome and cadmium concentrations are higher then other heavy metals streams and rivers because of high amount of industrial discharges. The data presented in investigation on the heavy metal contamination of marine organisms were different depending on pollution sources, element and species. According to the evaluation of inventories, the results are rising year by year.
In the present study, the heavy metal concentrations (zinc, copper, cadmium and lead) have been measured in dorsal muscle tissue of ten species (Trachurus mediterraneus, Sprattus sprattus sprattus, Mullus surmelatus, Sarda sarda, Mugil cephalus, Scorpaena porcus, Sparus aurata, Umbrina cirrosa, Spicara maena and Solea solea) from Sinop coast of the Black Sea, Turkey during fish season in 2010. Significant differences in metal concentrations were found between the species (P<0.05). In general, it was found that the levels of heavy metals studied were lower than the maximum permissible limit of the food regulations of the Ministry of Agriculture, Fisheries and Food (MAFF), the Turkish Food Codex and Commission Regulation (EC). Cd showed the lowest concentrations in all fish samples followed by Pb. The results of the present study were compared with the other studies and discussed.Keywords: Black Sea, fishes, zinc, copper, cadmium, lead. Anahtar Kelimeler: Karadeniz, balık, çinko, bakır, kurşun, kadmiyum.
In copepodites and adults of Calanus euxinus abundance, body length and weight, chemical composition and respiration rate in relation to age were studied during the cruise of R/V 'Knorr' in April 2003 in the southwestern Black Sea and in laboratory experiments. Data on morphology and physiology of C. euxinus collected during other seasons were also used in comparative analyses. At high concentrations of the diatom Proboscia alata during spring homothermy (6.8 to 8.5°C) C. euxinus did not undertake diel vertical migrations to the oxygen minimum zone (OMZ). The majority of the population was located above the OMZ, feeding on phytoplankton during nighttime and daytime whilst nearly 10% of copepodite stages IV and V (CIV and CV) and adults remained constantly in the OMZ. Although a diapausing stock of the population began to form in the OMZ, the majority of CV developed without diapause. The development times of copepodite stages at 8°C were determined on the basis of field observations of ontogenetic changes in carbon content and calculated absolute growth rates. Development time from CI to CV amounted to 22 d. In CV the time for lipid deposition from 0.008 ± 0.007 mm 3 in postmolts up to a maximum volume of 0.165 ± 0.054 mm 3 in intermolts constituted 26 d. The total generation time from eggs to adults is not less than about 66 d. KEY WORDS: Calanus euxinus · Lipid storage · Respiration · Growth · Black Sea · Spring cold · HomothermyResale or republication not permitted without written consent of the publisher Mar Ecol Prog Ser 374: 199-213, 2009 other hypothesis, Calanus, like other 'boreal relicts', entered the Black Sea when it was connected with the North Sea across Europe during the period of retreating glaciers (Zaitsev 2006). This is in agreement with the results of Papadopoulos et al. (2005) suggesting that the divergences between the northeastern Atlantic, Mediterranean and Black Sea C. helgolandicus populations are much older than the estimated dates of colonization of the Mediterranean and Black Seas. However, according to Polischuk (1984) the last connection between the North and Black Seas could have been in the Late Holocene (2800 to 2700 BP).Calanus euxinus is a dominant component of the zooplankton biomass in the Rim Current system of the Black Sea. The ecology of this species differs significantly from that of C. helgolandicus in other European seas due to the characteristics of the basin.Calanus helgolandicus typically inhabits saline waters (32 to 39 ‰) with temperatures of 9 to 20°C. This wide range is mainly due to seasonal variation; the temperature does not range widely between populations. Seasonal changes in abundance of C. helgolandicus are positively correlated with temperature (Bonnet et al. 2005) and food availability (Rey-Rassat et al. 2004). Overwintering C. helgolandicus descend to deep water and are separated spatially from the part of the population that develops in surface layers.In contrast, Calanus euxinus has adapted to the low salinity of the Black Sea waters (18...
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