Mytilus Galloprovincialis Lamarck Research Articles

Total and methyl-mercury content in bivalves, Mytilus galloprovincialis Lamarck and Ostrea edulis Linnaeus: relationship of biochemical composition and body size.

Mussels and oysters are of interest to pollution ecologists because they are widely distributed, suspension feeding invertebrates and are likely to accumulate pollutants from their environment (Goldberg 1975). Many authors have estimated the relation between the concentration of metals in the flesh and various biotic and abiotic parameters. Body mass (estimated in dry weight) is evidently an important factor governing the uptake of metals by these organisms (Boyden 1974, 1977). Cossa et al. (1980) showed, furthermore, that the highest concentrations of certain metals were often found in the smallest individuals. The relation between metal content and body size can best be described using Boyden's model (Walne 1972; Boyden 1974) which is useful for quantifying any physiological activities in relation to the dry weight of the specimens. The regression coefficient b in Boyden's model is a measure of an organism's control over metal accumulation in its tissues. In practice, widely different values can be obtained for regression coefficient b when investigating the same metal. Cossa et al. (1979) suggested that this variability is primarily correlated with differing amount of gonad development. Gonad growth and maturation are accompanied by numerous biochemical changes in the flesh, especially in relation to glycogen content. Moreover, rapid changes in both wet and dry weights occur during the spawning period (Zandee et al. 1980). These changes are more profound in the largest individuals. Fortunately, the reproductive cycle of the mussel Mytilus galloprovincialis Lam. and Ostrea edulis L. have been thoroughly studied in Limski kanal by Hrs-Brenko (1971). In the present paper we describe our investigation into the relationship between total and methyl-mercury content and body mass in mussels and oysters collected in Send reprint requests to M. Najdek at the above address

Principal component analysis for the identification of pollution sources in mussel survey by trace metals.

Principal component analysis has been applied to analyze the correlation matrix obtained from a 8 X 43 data matrix. The 8 trace metals are Mn, Co, Ni, Cu, Zn, Cd, Hg, Pb, which are contained in the soft part of mussels (Mytilus galloprovincialis Lamarck). Mussels were sampled from two sites in the Gulf of Trieste. In both samples, 76-78% of the total variance is explained by the four principal components. The orthogonally rotated factor matrix indicates that Co and Ni are bonded to the first principal component and Cd and Pb to the first (site 2) or second principal component (site 1). The origin of trace metals in the soft part of mussels from the Gulf of Trieste is discussed.

Total and methyl-mercury content in bivalves, Mytilus galloprovincialis Lamarck and Ostrea edulis Linnaeus : Najdek, Mirjana and Jasenka Sapunar, 1987. Relationship of biochemical composition and body size. Bull. environ. Contamin. Toxicol., 39(1):56–62

Total and methyl-mercury content in bivalves, Mytilus galloprovincialis Lamarck and Ostrea edulis Linnaeus : Najdek, Mirjana and Jasenka Sapunar, 1987. Relationship of biochemical composition and body size. Bull. environ. Contamin. Toxicol., 39(1):56–62

Settlement of mussels ( Mytilus galloprovincialis Lamarck) on rope collectors in the estuary of the River Krka, Yugoslavia

The 25-km 2 estuary of the River Krka, Yugoslavia, supports a large natural population of mussels. Artificial culture on hanging ropes is now beginning, and for this it is necessary to know the best areas, depths and times for settlement and collection of seed. In this experiment, plastic rope test collectors were set each month from May 1981 to April 1982 at three sites. After 2 months, settled mussels were removed from collectors. Water temperature and salinity measurements were made weekly at each site. Maximal settlement at the two upstream sites was found in September, when 350 and 485 mussels were recovered from 125 cm 2 of rope at 2 m depth. However, at the site further downstream, good settlement occurred throughout the year, peaking at 5250 mussels per 125 cm 2 of rope at 3 m depth during April. Such productive sites will be extremely useful in supplying seed for mussel farms in this area.

Principal component analysis as a tool for studying interdependences among trace metals in edible mussels from the Gulf of Trieste.

Principal component analysis has been applied to analyze the correlation matrix obtained from a (6 X 44) data matrix. The 6 trace metals are Co, Ni, Cu, Cd, Hg, and Pb, which are contained in the soft part of edible mussels (Mytilus galloprovincialis Lamarck) from a hatchery on the gulf of Trieste. In the space of "eigenvectors", the dimensions are reduced to 3 principal axes, which account for about 77% of the total variance. The unrotated factor matrix obtained by the principal components shows that Co, Ni and Cu are bonded to the first principal component, Cd and Pb to the second, Hg to the third. This picture is also assessed by the Varimax-rotated matrix and it is tentatively explained, at least in part, by considering the associations of the trace metals from various geographical sources.

Heavy metals at trace level in edible mussels (Mytilus galloprovincialis Lamarck) from the gulf of Trieste.

The concentration of heavy metals (cobalt, nickel, copper, cadmium, mercury and lead), which are present at trace levels in the edible part of mussels (Mytilus galloprovincialis Lamarck) from hatcheries in the gulf of Trieste, is normally or log-normally distributed, according to a statistical test sensitive to asymmetry of the distribution. A log-normal distribution appears valid for describing nearly all trace metals, in particular toxic heavy metals like cadmium, mercury and lead. The frequency distribution of these metals has nearly the same asymmetry, although the one-way analysis of the variance shows that sample means come from different population means characterising the particular hatchery.