Currently, China has about 6.7 million hectares of farmland area exposed to the threat of alkalinization, plus nearly 4 million hectares at the risk of desertification. According to the latest result of a survey conducted with remote-detection technology by the sector concerned in 1992, the loss of the soil area was 3.69 million square kilometers, of which 1.794 million square kilometers was caused by water- erosion, and 1.876 million square kilometers by win-erosion. The amount of soil carried from the land of China to the coastal waters through the rivers amounts to 1,780 million tons. Adding accumulated mud and sand to this figure makes total erosion of over 5 billion tons.
Since 1949, the Chinese government has taken a series of measures to improve conditions of agricultural production, chiefly as follows. The measures： (1) improvement of the farming system by extending areas for intercropping, double or multiple cropping, and crop rotations; (2) aggressive development of farmland reclamation projects, by e.g., reclamation of about 35 million hectares of farmland in Heilongjian, Hainan, Xinjiang, Yunnan, etc. which have reclaimed about 650,000 hectares of farmland from the sea; construction of state-owned automated farms, which have become important bases for production of food, cotton, rubber and tropical economic crops; (3) powerful enrichment of the farmlands with low productivity, by construction about 6.5 million hectares of horizontally terraced farms, improving about 45 million hectares of alkaline lands, and conducting repairing work on about 4.5 million hectares of washed-away areas; (4) construction of drain and irrigation facilities, which increased the effective irrigable land area from 16.00 million hectares in 1949 to 493.65 million hectares in 1995, of which 322.10 million hectares benefit from mechanical and electrical drainage and irrigation.
Associated with population growth and developing construction of cities and villages, the contradiction of "more people" and "scarce rationally land" is becoming increasingly critical. Therefore, the Government values and utilizes every inch of land carefully and effectively as basic national policy, and intends to emphasize the following six points for a suitably long period of time.
