Analysis of the magnetic anomaly field of the volcanic district of the Bay of Naples, Italy

We here present and discuss the results of the analysis and qualitative interpretation of two magnetic surveys performed in the Bay of Naples in 1998 and 2000. A map of the Bay of Naples based on the data acquired during these surveys has already been published by the Italian CNR-IAMC Research Institute. We re-processed the same data to produce maps of the pole reduced, analytic signal and horizontal derivative data and correlated them with the bathymetry and the gravimetric data of the area. The analysis shows strong anomalies in the NW and NE volcanic areas of the Bay of Naples, while the central area seems magnetically quiet. In the Phlegrean area the maps clearly show the southern rim of the Phlegrean caldera and demonstrate that while the Magnaghi Canyon is correlated to gravimetric highs and magnetic structures, and can therefore be interpreted as an active lineament, most of Dohrn Canyon is not characterized by volcanic activity and does not correlate to any gravimetric or magnetic structures. An important round-shaped magnetic anomaly is for the first time identified in the central slope of the gulf between the two canyons, probably correlated to a large buried volcanic edifice. In the Vesuvian area some intense circular anomalies, aligned in the NNW–SSE direction, are localized in the Torre del Greco and Torre Annunziata offshore, related to the submerged part of Vesuvius and possibly connected to buried vents.     

The state of the aquatic environment and biota during operation of trout-breeding pond farms

The paper presents the results of studying chemical and biological quality characteristics of the aquatic environment in the area of operation of trout farms in Kondopoga Bay, Onega Lake. The concentrations of biochemically labile substances and phosphorus were found to increase near the ponds. The development dynamics of phytoplankton, zooplankton, and benthic organisms in the zone of pond farms. When the procedure of fish production is strictly followed, the effect of ponds on the aquatic environment and biota is minimal.     

Heritability and genetic correlation of survival in turbot (Scophthalmus maximus)

We analyzed the survival data of the offspring from 21 sires and 42 dams of turbot. The results show that the cumulative survival rates for turbot from 2 to 18 months range from 17.5% to 28.5%; main mortality occurred during months 2–5; and the highest survival rates of families were 97.9%, 98.8%, 99.4%, 99.7% during months 2–5, 5–6, 6–8, 8–11, and 11–18, respectively, and 99.5%, being 53.5%, 23.8%, 19.5%, 14.9%, and 13.2% higher, respectively, than the mean values in each period. In all periods, the estimated heritabilities for survival were very low without significant difference from zero (P≫0.05) (values ranged from 0.06 to 0.12), indicating low additive genetic effects. The genetic correlations of survival among families in different periods were all positive, but low in magnitude (values range from 0.03 to 0.31). Genetic correlations between long-term survival and other periods’ survival had negative values (−0.06 and −0.15) and three positive values (0.16, 0.12 and 0.14). Genetic correlations between survival and weight were all positive, except for survival at months 2–5 and weight at 18 months, which was not significantly negative (−0.18).     

Orbital evolution of Jupiter’s new outer satellites

Data on recently discovered outer satellites of Jupiter are used to analyze their long-period orbital evolution. We determine the extreme eccentricities and inclinations, as well as the circulation periods of the pericenter arguments and of the longitudes of the ascending nodes. The satellite orbital elements are plotted against time. The methods of analysis are identical to those that we used to analyze the orbital evolution of Uranus’s and Saturn’s new outer satellites.     

Analysis of the upper limit of the Southworth-Hawkins <Emphasis Type="Italic">D</Emphasis> criterion for the Pons-Winneckid and Perseid meteoroid streams

The value of the upper limit of the Southworth-Hawkins D criterion for the Pons-Winneckids (June Bootid) and Perseids meteor streams is analyzed on the basis of the comparison of the parent comet orbit with the model orbits of meteoroids ejected at different points of the comet orbit with the most likely ejection velocities. The change of the D values is investigated depending on the dynamic evolution of the streams by integrating forward the orbital elements of the model particles using the Cowell method taking into account the perturbations from all planets. It is shown that after ten rotations, for Pons-Winneckids the upper limit of the D criterion is higher than 0.5 and for Perseids the D criterion does not exceed 0.2.     

Currents and intensity of turbulent processes in the Gavan’ Gaidamak Inlet (Vostok Bay, Peter the Great Bay, Sea of Japan)

Presented are the data of observations carried out in the fall of 2000 in the Gavan?? Gaidamak Inlet (Vostok Bay, Peter the Great Bay, Sea of Japan). It is revealed that the main transport of water takes place in the surface horizons from 0 to 1?C2 m predominantly in the meridional direction (north-south). It is demonstrated that in spite of not being under wind influence, the inlet area has a high degree of water flow turbulization. It was also registered that the wind-induced phenomena promote the development of turbulent processes and serve as the main self-cleaning mechanism of the inlet.