The local aspect of aging is often ignored. However, municipalities, in particular cities will be affected by the consequences of population aging, in particular a decrease in tax revenues and an increase of expenditures on public goods demanded by the elderly. In this paper we use a static general equilibrium model to analyse the impact of aging on city’s finances. We show that an increase in the number of pensioners will raise the cost of public goods. However, an increase in the number of working elderly can alleviate the situation.

The observations on Myzus persicae and Macrosiphum euphorbiae development were carried out on boxthorn (Lycium halimifolium) growing in various places of the city ofWroclaw in 1999-2001. They concerned the following issues: aphid population dynamics and aphid age and morph diversity in population structure. Aphids infested only certain boxthorn bushes and other bushes were free of these insects. M. persicae infested more bushes than M. euphorbiae did. The first species appeared 7-10 days earlier on boxthorn than the second one. Time of the maximum population density of both aphid species was similar. Age structure of M. persicae and M. euphorbiae populations was similar. The youngest larvae (L,-L,) predominated and the least numerous were alatae females. Coccinellids were the most numerous aphid predators on boxthorn.