(1) The alarming and incessant growth of population is causing serious economic problems in almost all continents. Great pressure is being placed on arable land, water, energy, and biological resources. As the world population grows, the food problem will become increasingly severe. The most vulnerable will be population in developing countries. The per capita availability of food grains has been declining for the past 25 years. Certainly with a quarter million people being added to the world population each day, the need for grains and all other food will reach unprecedented levels.
Below, world population and its growth trends are given.
10,000 years ago, 10 million people By 1850, population was 1 billion 80 more years to reach 2 billion in 1930 45 years, it doubled again (4 billion in 1975) 12 years to reach 5 billion (1987) 6 billion in 1999 By the year 2020, there will be 8 billion
(2) There are about quarter of a million people added to the planet per day. This exponential growth is mostly happening in the developing nations.
(3) More than 99 percent of the world's food supply comes from the land, while less than 1 percent is from oceans and other aquatic habitats. The continued production of an adequate food supply is directly dependent on ample fertile land, fresh water and energy. As the human population grows, the requirements for these resources also grow. Even if these resources are never depleted, on a per capita basis they will decline significantly because they must be divided among more people. At present, fertile agricultural land is being lost at an alarming rate. The shortage of productive fertile land combined with decreasing land productivity is the major cause of current food shortages.
Water is another critical item for all crops. Massive amount of water (4) is required during the growing season for cultivation. In fact, agricultural production consumes more fresh water than any other human activity. In many countries, people are facing shortage of fresh water. Competition for water resources among individuals, regions, countries and associated human activities are already occurring with the current world population. Water resources, critical for irrigation, are under great stress as populous cities, states, and countries require and withdraw more water from rivers, lakes, and aquifers every year. A major threat to maintaining future water supplies is the continuing over- use of surface and ground water resources.