Human errors in lifestyles and production models

Population trends are crucial determinants of economic, social and environmental change. The 1999 medium fertility scenario predicts 9.5 billion in 2050, peaking at 11 billion in 2200. You can still get scary figures by projecting 1995 fertility rates, ignoring the declines in fertility. There have been large declines in fertility in many Third World countries.
In June 1999 it was reported that the average Mexican woman had 7 children in the 1970 but has 3 children today. Bangladesh and India have also had large declines in fertility. The world’s most populous country is China. Its rate of increase has declined recently. The earth and accessible and usable planets place a limit on the possible human population. Population may eventually approach this limit, thus necessitating actions by sovereign countries or other entities to limit their population.
World population would not be a problem if there were unlimited land, unlimited water, unlimited resources. Unfortunately, with overpopulation, there is the problem of sharing the same sized pie with smaller and smaller portions. People in developed countries who have been accustomed to a better quality of life are reluctant to give it up. In many cases, more efficient use of resources has come along hand-in-hand with improved quality of life. But there are still problems of overconsumption, exploitation, the short-sighted search for an ever-higher quality of life, and the greed of companies and individuals in cutting corners resulting in pollution and reckless use of raw materials. Less-developed countries that, in the past, had smaller populations such that slash-and-burn agriculture had less impact, cities had fewer vehicles to send pollution into the air, and industries were not as attracted by cheap labor and thus polluted rivers and the air less.

Sustainability is the practice of conservation that will allow people to have enough resources through their life and the lives of future generations.

Sustainability and Population
Population is not of concern if there are enough resources to go around. Important resources like water of suitable quality for growing crops, drinking, cooking, and cleanliness, fertile soil for growing food and trees, and fuel for warmth and cooking.
Depletion of important resources leads to poverty, disease, malnutrion and often death. Impoverished people are usually forced to destroy their environment in order to survive. Sustainability is the practice of conservation that will allow people to have enough resources through their life and the lives of future generations. Sustainability is possible by conserving energy, materials, resources, by new technologies, and by ensuring that the number of births is low enough so that there is enough to go around.