Besides areas with primeval Nature, it is also necessary to protect man-made ecosystems. Under European conditions it is particularly important to turn into protected areas some near-natural landscapes which have never undergone great changes in land-use. One of these territories in the eastern Baltic region is the area of Matsalu Bay, which since 1957 has been the site of the largest Baltic nature reserve, possessing highly specific and valuable ecosystems. The Matsalu landscape is characterized by pasture lands, moist meadows, vast reed-beds, wooded meadows, and juniper groves, which have all been subjected to extensive human influence in the course of several centuries. Under contemporary conditions of management the preservation of these landscape types is somewhat difficult, but it is necessary to find suitable measures to effect it.

Representatives of national academies of science from throughout the world met in New Delhi, India, from 24 to 27 October 1993, in a ‘Science Summit’ on World Population. The conference grew out of two earlier meetings—one of the Royal Society of London and the United States National Academy of Sciences, and the other being an international conference organized by the Royal Swedish Academy of Sciences. Statements published by both groups expressed a sense of urgent concern about the expansion of the world's population and concluded that if current predictions of population growth prove accurate and patterns of human activity on the planet remain unchanged, science and technology may not be able to prevent irreversible degradation of the natural environment and continued poverty for much of the world.

This article examines, through a molecular perspective, the ‘ozone-friendly’ refrigerants R-134a and R-123 vis-à-vis R-12 and R-11, which are targeted to be phased out under the Montreal Protocol on Substances that Deplete the Ozone Layer, Final Act (1987). It appears that the molecular weight, size parameter, and dipole moment, of R-134a and R-123, may induce a pronounced effect on the chemical equilibrium of ice particles in the polar stratospheric clouds and subsequently influence the photochemical reactions therein.

Non-polar, high-molecular-weight perfluoropropane (R-218), could be a better substitute for R-12, while R-134, which is a non-polar HFC of the ethane family, could also be a candidate although its molecular weight is lower than that of R-12. The search for a good substitute for R-11, however, must continue.

Increasing public awareness of the need to protect Environmentally Sensitive Areas (ESAs), as well as the establishment of regional municipalities, provided the impetus for local governments to initiate ESA planning in Ontario. As of 1981, twenty municipalities—primarily regional municipalities and counties—had adopted ESA programmes.

This paper examines the current status of ESA-protection planning in Ontario and the problems encountered by municipalities in adopting and implementing ESA programmes. Using a questionnaire survey, data were collected concerning 66 municipalities, and a review was carried out of the ESA policies in 36 Official Plans. The results show that an additional 11 municipalities have adopted ESA programmes since 1981, and that most of these have been designated cities. The primary problems encountered by municipalities in implementing ESA-protection programmes have been a lack of landowner support, weakness of any provincial policy-directive, and shortness of funding. These problems are also faced by uninvolved municipalities, and play an important role in preventing them from adopting ESA programmes.

If a wider municipal adoption of ESA programmes is to be achieved, a stronger commitment will be needed from the Provincial Government in the form of guiding policies, financial assistance, and incentives to landowners who wish to protect their sensitive lands. A greater emphasis on landowner contact and public education programmes will also be required. Municipalities should cooperate with other conservation agencies and organizations in working towards this end.

At the 12th General Assembly of the International Union for Conservation of Nature and Natural Resources, held at Kinshasa, Zaire, in September 1975 (see the report in press for our next issue), a new programme was agreed upon for the Union.