On October 31, 2011, with the birth of Oishee at 12:01 am in Bangladesh, UNFPA and government of Bangladesh celebrated the arrival of the 7 billionth global citizen on the planet earth. As of June 26, 2012 the world human population is estimated to be 7.022 billion by the United States Census Bureau, and over 7 billion by the United Nations. The population is expected to reach between 8 and 10.5 billion between the year 2040 and 2050. In fact, the world's population grows at a near-record pace, with a population equal to New York City's added every month, and equal to Germany's added every year.

Anton van Leeuwenhook (1673-1723) estimated that the Earth could support a maximum of 13.4 billion people. Gregory King predicted the Earth could support 6 to 12 billion humans. "Liebig's Law of the Minimum" approach estimates human carrying capacity ranges from 1 or 2 billion people living in prosperity, to 33 billion people fed on minimum rations and using all suitable land for high-intensity food production. Scientists now believe that the human carrying capacity of Earth may be approximately 12 billion. Hypothetically, if the human population continues to grow at the present rate, the mass of people would be equal to the mass of the earth within 1,600 years.

Unesco projects that total global water use will rise by 32% between 2000 and 2025, and will continue to rise. Rapid population growth and increased total water consumption are rapidly depleting the availability of water. Between 1960 and 1997, the per capita availability of freshwater worldwide declined by about 60%. Another 50% decrease in per capita water supply is projected by the year 2025. Water availability in Bangladesh is around 90 billion cubic meters (BCM) against the demand of about 147 BCM, a shortage of nearly 40%. Kofi Annan's Millennium Report says that if present trends continue two out of three people on the planet will live in countries considered to be "water stressed."

Another major threat is fresh water pollution. Approximately 95% of the water in developing countries is polluted. Developing countries discharge approximately 95% of their untreated urban sewage and industrial pollutants directly into surface water. New York disposes of 200 million gallons raw sewage into the Hudson River each day. The noisome pollution from chemical waste of mills and factories, home waste, medical waste, sewage, dead animals, plastics, and oil has made Buriganga a dead river. As a result of over exploitation by the population of Dhaka city, the extent of pollution is so extreme that there is no fish or aquatic life in this river. Everyday almost 4,500 tons of solid waste and 20,000 tons of tannery wastes are released in to Buriganga. There is no available technology to avert its dying state. Until we plan our city for human habitation to the limit of its natural capacity, our cry from the heart to salvage Buriganga will always be a cry for the moon to save the day.

In addition to limitations due to population increases, high per capita consumption levels in the United States and other developed nations also put pressure on natural resources. Each American consumes about 50-times more goods and services than the average Chinese citizen. Achieving an average European standard of living ($12,310 per capita/yr) or an average US standard of living ($26,000 per capita/yr) appears unrealistic for most countries because of serious shortages of the basic natural resources.

Oil is the heart of humanity's enormous energy economy as well as at the heart of its food supply. Oil and its companion natural gas together make up about 60% of humanity's primary energy. Fossil fuel contributes more than 90% of global commercial energy production. Approximately 70% of the fossil fuel is burnt by the industrialised nations, who have less than a quarter of world's population. 22% of the world's fossil fuel is consumed by 4% of US population. Currently, only 1.25% of China's population possesses a car. The forecasts are that in 2031 China will have a per capita income close to that of the US in 2004, and would have a billion vehicles. If they all needed to run on gasoline there is simply not enough oil and, of course, the greenhouse gases produced would heat up the whole world distressingly.

In 1798 the Reverend Thomas Malthus hypothesised that population growth would exceed the growth of resources, leading to natural checks by disease, famine, and war. There is a growing trend in strategic circles to view environmental and resource effects -- rather than political orientation and ideology -- as the most potent source of armed conflict in the decades to come. With the world population rising, global consumption rates soaring, energy supplies rapidly dwindling and climate change eradicating valuable farmland, the stage is being set for persistent and worldwide struggles over vital resources.

Lack of water and agricultural land is a significant contributory factor to the tragic conflict unfolding in Darfur. Afghanistan, according to The New York Times, is "the Saudi Arabia of lithium." Soviet specialists discovered huge gas reserves there in the 1960s and drained away 2.5 billion cubic meters of Afghan gas annually. Two-thirds of the oil in the world is in the Middle East, much of it under Iraq and Iran, the axis of oil, the current targets of the US war on terrorism. Control of oil is integral to Washington's official goal of world domination. With regard specifically to the Middle East we have the Carter Doctrine: "An attempt by any outside force to gain control of the Persian Gulf region will be regarded as an assault on the vital interests of the United States of America, and such an assault will be repelled by any means necessary, including military force." Competition for land was identified as a significant part of the backdrop to the post-election violence in Kenya in early 2008, and to the 1994 genocide in Rwanda; water and land have both been identified as conflict drivers in Ethiopia and Somalia.

Renewable resources like firewood and fresh water have reached the ending phase. Most scientists agree that the overall human pressure on the environment is a product of three factors: population, consumption and technology. In the population-environment debate these factors are often emphasised as the dominant cause of rising environmental deterioration. For some, it is inexorable population growth. For others, it is polluting technology. Still others stress excessive consumption, policy and market failures, or common ownership of key environmental resources. The bottom line is that all of these viewpoints are correct some of the time; none of them is correct all of the time. A comprehensive approach to understanding the population-environment linkage must include all three.

Bringing about a sustainable balance between ourselves and the planet we need, in very short order, to reduce our population, our level of consumption, or both. There are two ways a population can regain a balance with the carrying capacity of its environment. If the population stays constant or continues to rise, per capita consumption must fall. If per capita consumption stays constant, population must decline. Where the balance is struck between these endpoints depends on how close the population is to a subsistence level of consumption. If this situation is not wisely addressed, it seems inevitable that this will wrap-up to its logical conclusion -- mass starvation, war, elimination of the weak and survival of the strongest. Question is who will be the luckiest to be among the short list of the survivors?

The writer, a physician and specialist in Hospital Management, is Deputy Assistant Director of Medical Services, Comilla Cantonment.