Curitiba - Brazil

Curitiba, Brazil has become known as the world's greenest city. Although its population has more than doubled in the past generation, the city's environment has been greatly enhanced, increasing the wealth and the welfare of its citizens. Among other things, the city government planned housing and work locations to provide high quality living and working space, with efficient rapid transit systems connecting them. It has also developed a distinctive garbage collection system for the slum areas, where the government exchanges bags of food for garbage that people collect from their own neighbourhoods. Good urban planning promoted the well being of both people and their environment.

Rural Japan and Alpine Europe

The exodus of people from rural Japan and alpine Europe may be reducing biodiversity. Many rural populations in the more developed regions are ageing and not replacing themselves as young people move to the towns and larger urban areas. While conclusive evidence is lacking, it is possible that this exodus reduces biodiversity. In Europe, farms that once grew a variety of crops and supported a large number of wild bird and animal species have been abandoned, leaving the land to return to more uniform habitats with fewer species. In Japan, abandoned rice fields destroy wetlands that once supported a wide range of wild species and did much to purify water.

Thailand Gibbon Sanctuary

Development programmes in Thailand have extended primary health care, education and good family planning services to the rural areas. Together with the fast pace of economic development, this has produced one of the most rapid declines in fertility known in the modern era. One result is that the population surrounding a protected area - the habitat of an endangered gibbon - has stabilised and begun to decline, reducing the pressure on the gibbon habitat and enhancing the local environment.

Himalayan Deforestation and Ganges Siltation

The deforestation of the Himalayas which causes siltation in the Ganges River represents one of the most commonly perceived effects of rapid population growth. Under conditions of subsistence agriculture, and using wood for fuel, rapid population growth has had a devastating effect on the foothills of the Himalayas. Marginal land is cleared for farming and trees are cut for fuelwood. The resulting deforestation produces soil erosion, reduced farmer income, and downstream siltation of the Ganges River. This region has received little or no government investments to help improve farming practices or to increase the welfare of the people through education, health, and family planning services.