The God Species_ How the Planet Can Survive the Age of Humans - Mark Lynas [73]
SEX AND THE CITY
As a general rule—and making an exception for indigenous people and other communities who have demonstrated a long-term commitment to the sustainable use of their local environments—the fewer people who live in or close to rain forests and other important ecological biomes the better. Rural depopulation and urbanization in developing countries are often decried by those who are concerned about the relentless expansion of megacities, which seem terribly unsustainable because of their noise, sprawling slums, congestion, and pollution. But from the perspective of sustainable land use and habitat protection, the more that growing numbers of people can be persuaded to herd themselves into relatively small areas of urban land, the better for the environment.
Village life, particularly in extremely poor developing countries, should not be romanticized by outsiders. Whenever they are given the chance, younger generations tend to flee to the cities, where they have many more livelihood options and can escape the cultural oppression that is often a hallmark of traditional societies. In many parts of the world, if you want to marry the person you choose, be openly gay, be female and have a career, or avoid daily backbreaking labor carrying water or fetching firewood, then you probably need to move to the city. In 1975 there were just three megacities of over 10 million people. Today there are 21. It sounds scary, but this unstoppable shift toward urbanization actually ranks as one of the most environmentally beneficial trends of the last few decades. As the UN Population Fund wrote in a recent report: “Density is potentially useful. With world population at 6.7 billion people in 2007 and growing at over 75 million a year, demographic concentration gives sustainability a better chance. The protection of rural ecosystems ultimately requires that population be concentrated in non-primary sector activities and densely populated areas.”60
By the end of 2011 the world’s population will stand at 7 billion. Seven billion people is an incredible number, but standing shoulder to shoulder we would all comfortably fit within the city of Los Angeles.61 City living is seldom lauded by environmentalists, but it may be our most environmentally friendly trait as a species, because urban dwelling is vastly more efficient than living in the countryside. Shops and other services are more concentrated in town and city neighborhoods, and urban residents are much more likely to use public transportation, share heating and housing, and have lower carbon footprints than their rural brethren. But given the scale of global population growth, the challenge still seems daunting: the world will need to accommodate 2 billion more urban dwellers by 2030, a rate of expansion equivalent to building about 13 great cities (each with over 5 million inhabitants) per year, almost all in developing countries.62
But consider against this two pieces of good news. First the rate of population growth is declining, having fallen from 2.2 percent at its highest in the early 1960s to 1.2 percent today.63 UN projections for peak absolute population numbers keep being revised downward, and its “low variant” projection has now come down to just eight billion people by 2050.64 In some countries the population is already falling in absolute terms: In Russia the overall population has fallen from 148 million to 142 million since the 1990s. Second, the amount of land space taken up by cities is actually relatively small compared with the number of people they shelter: Satellite image composites show that urban sites cover only