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The results of [O/Na] abundance modelling in globular clusters NGC 2808 and NGC 6752 are presented. The evolutionary scenario allowing to reproduce characteristic observed features of [O/Na] distribution function has been suggested. Slow winds from massive rotating stars are assumed as a producer of chemical anomalies. It is shown, that the abundance pattern in globular clusters can be explained within a model with a limited mixing of stellar wind and surrounding interstellar gas. This means in other words that the second generation stars are born in a vicinity of individual massive stars of the first generation from the heterogeneously distributed material ejected by these stars.

Numerical model of dynamical evolution of globular clusters(GCs) is described, with an emphasis of the mass loss rate in tidal interactions with the Galaxy. On a set of models dependence of the tidal destruction on cluster parameter sand initial conditions, such as: the initial cluster mass, its initial position in the Galaxy, the eccentricity of the orbit–are studied. An analytical description of tidal destruction of GCs and simple estimate of their life times is proposed.

We consider the evolution of metal- enriched gas exposed to a superposition of time- dependent radiation field of a nearby starburt galaxy and nearly invariant (on timescales 100 Myr) ex- tragalactic ionization background. We study the evolution of ionic species (particularly those com­monly observed in galactic circumference) depending on the galactic mass and star formation rate, and derive conditions for the highly ionized oxygen, OVI, to appear in extended galactic haloes in absorption or emission spectra. We have found that the max­imum OVI fraction can reach ~ 0.4 — 0.6 under the action of both ionizing radiation field, which is typical in haloes of starforming galaxies, and the extragalactic background, the fraction remains high in a wide temperature range. We have shown that the OVI fraction is high enough that even for ~ 0.1Zʘ metallicity we can explain large OVI column densities (log[N(OVI), cm-2] ~ 14.5 — 15.3) observed in the haloes of starforming galaxies by Tumlinson et al. (2011). Thus, the requirements to the sources of oxygen supply into the extended haloes become reasonably conservative.

We present results of modelling of the mass-metallicity relation for the Local Group dwarf spheroidal (dSph) galaxies. In this work, we use a single-zone chemo-dynamical model. Our model is based on the scheme suggested by C. Firmani and A. Tutukov (1992). The behaviour of the dark-to-visible mass ratio has been taken from M.-M. Mac Low & A. Ferrara (1998). We have considered two classes of models: open and closed. The obtained mass- metallicity relation for the open model shows that the galaxies can be divided into two distinct classes: low-mass (Mtot < 108Msun) and high-mass (Mtot > 108Msun) groups which agrees with observation data.