f population has permeated all aspects of social and economic life; in fact, many difficulties China has encountered in its economic and social development are directly related to the problem of population.
Over the vast territory of China, the space suited for people to live and engage in economic activities is limited and population distribution is extremely uneven. Plains and hilly land account for 12.0 percent and 9.9 percent respectively of China's total land area, totalling only 21.9 percent, while basins, mountains and plateaus account for 18.8 percent, 33.3 percent and 26.0 percent each, adding up to 78.1 percent. Many of the mountain, plateau, hilly and basin areas are unsuited for living. China's humid and semi-humid areas, appropriate for living, account for only 47 percent of the total land mass, while the arid and semi-arid areas account for 53 percent. Now, 94 percent of China's population live in the eastern part, which accounts for 46 percent of the country's territory, particularly in the southeastern region where the natural environment is better and the economy is relatively developed. The State Statistical Bureau estimates, on the basis of data collected in the third national census in 1982, that 20.3 percent of China's population live in areas over 500 metres above sea level, whereas in the world's population as a whole, only 10 percent live in areas over 400 metres above sea level. At present, there are still 70 million people in China living below the poverty level, of which the majority live in the western region where the geographic environment is harsher. Obviously, the poverty of the population is closely related to their poor living conditions. Besides this, China's per-capita average of forested land, grassland and freshwater resources amounts to only one-ninth, one-third and one-fourth of the respective world averages. "Food is the first necessity of the people." To solve the problem of feeding a population of 1.2 billion is a big challenge to China. Now, cultivated area in China accounts for only onetenth of its territory. In contrast, cultivated land in India accounts for 55 percent of its territory, with a per-capita average twice that of China. Although cultivated land in the United States makes up for only 20 percent of its territory, still its per-capita average is nine times that of China. The greatest pressure on China's agriculture, particularly grain production, is the continuous growth of the population and incessant shrinkage of the cultivated land. The United States and India, as well as China, are all major grain-producing nations in the world. Though its cultivated land is less than the United States and India, China ranks the first in the world in terms of grain output; its per-unit grain yield is much higher than the world average. But, as China's population is almost five times that of the United States, its per-capita share of grain is less than one-fourth of the latter. In 1993, despite a bumper harvest witnessed in China's grain production, the per-capita share of grain was only 387.3 kilogrammes. Forecasts show that China's per-capita share of grain will remain at the low level of less than 400 kilogrammes of crude grain for a long time due to the continued growth of the population size in the future. If China fails to effectively check the over-rapid growth of the population and alleviate the great pressure wrought by the population growth on cultivated land, forests and water resources, an ecological and environmental deterioration will become inevitable in the coming decades, profoundly endangering the minimum living conditions of the overwhelming majority of the Chinese people as well as the sustainable development of their society and economy.
On one hand, China's abundant labour force is of course conducive to development. On the other, however, it will be considerably difficult to tackle the problem of employment of a continuously growing labour force under the shortage of funds and the relative insufficiency of resources. Now, nearly 20 million young people reac