1: Discuss on the impact of human population explosion on the environment and the world food problem as a biological and social issues.

The term ‘population explosion’ refers to the situation that the human population grows so fast that it exceeds the carrying capacity of the environment such that human lives are threatened. It is evident that some areas on the earth are already so over-populated that a single disturbance, such as a flood, drought or crop failure, will result in the deaths of thousands or even millions of people.

One of the major problems of population explosion is food supply. Food is known as a major limiting factor for organisms. The overall production of food in the world should still be enough to feed the present population. There is a surplus of food in developed countries while starvation and famine occur in some developing countries. It is estimated that one-third of the world’s population is consuming over one-half of the world’s food supply. The present problem is mainly an unbalanced food supply due to the following reasons.

1: In order to earn more money in the export market, farmers in many developing countries grow cash crop. Therefore, less land is available for growing food crops.

2: In some countries, the pastures are overgrazed, for example, people allow too many cattle and sheep to feed on the pastures. The vegetation is eaten away at a rate much faster than it grows. Consequently, the fertile topsoil is stripped off, resulting in the transformation of pastures into deserts.

3: Deforestation is another reason for turning fertile soils into deserts in some countries. As trees have been cut down, the soil can no longer retain water. Thus the exposed topsoil is subjected to soil erosion.

4: Large quantities of food are being wasted in developed countries due to the wasteful eating habits of the people.

5: Modification of the environment by human activities has resulted in increased chances of having natural disasters such as droughts, floods and pests in many parts of the world. This may lead to the slow-down of food production.

6: Frequent warfare in some developing countries seriously disturbs the production of food.

Environmental impact:

The lining of human beings depends upon a large variety of natural resources including food, energy, water and land. They also depend on various materials for medicinal, recreational and many other purposes. As the population continues to grow, there is an increasing rate of consumption of resources in the environment. Thus the natural resources that support human population are being exhausted at a faster and faster rate. At the same time, utilization of natural resources results in production of waste products, which continuously pollution problems are becoming more severe as the human population grows.