There are three trends most widely blamed for causing environmental problems—population growth, ization and industrialization. The world’s population is increasing by around 85 million every year—the equivalent of, say, another Mexico. The pace of growth has come down a little since the 1960s, but according to United Nations projections it remains fast enough to push the world’s population above 9 billion, from around 6 billion today. Most of that growth will be in developing countries. The population explosion of the past few decades has been due to a happy trend: a dramatic rise in life expectancy (平均寿命), thanks in part to the spread of modern medicines and better sanitation. But, say environmentalists, the world’s Supply of natural resources is finite, and in some regions particular resources are already scarce (water in the Middle East, certain species of fish in the North Atlantic). How can these resources be made to go round an extra 3 billion people Increasing ization is another environmental worry. The historic movement from country to town in rich countries is now being echoed in poor countries, but on a much bigger scale. The UN expects that between 1990 and 2025 the number of people living in areas will double to more than 5 billion, and that 90% of that growth will be in developing countries. In Africa and Asia more than half the population still lives in the countryside, compared with only a fifth in Europe and North America. Country-dwellers in developing countries are moving to cities for the same sort of reasons as in the rich countries in the 19th century: they are pushed by a scarcity of farm jobs, and they are pulled by the hope of better jobs and a better life. Governments in many developing countries have accelerated this progress by pursuing economic policies that discriminate against agriculture: until recently, for example, many governments kept food prices artificially low. The reason why ization is likely to harm the local environment is simply that people are much more densely crowded together. Burn a tyre in the countryside, and no one may worry about it; but in the city it will cause a great many coughs and splutters (杂乱的声音). Industrialization, too, is an obvious cause of environmental problems. Today’s rich countries moved first from agriculture to manufacturing industries which use resources intensively, and later to services and less polluting types of manufacturing. Many developing countries are now undergoing that first transition at the same time succumbing to (屈从于) a temptation not available in the 19th century: motor vehicles. |