PEOPLE'S REPUBLIC OF CHINA

          The plant nutrient resources applied in China contains mainly nitrogenous fertilizer, phosphate fertilizer and potash fertilizer. Before the first half of 80s, the input of them depended more than fifty percent on organic fertilizer such as human manure, livestock manure, stalk manure and green manure. Yet from the second half of 80s, mineral fertilizer’s contribution to the input of plant nutrients began to outstrip that of organic fertilizer. In 1991, China’s total fertilizer input amounted to 23.5 million ton, of which 54 percent came from mineral fertilizer. The percentage kept going up hence on. In addition, with the development of intensive agricultural practices, more micro-nutrient fertilizers were applied in more and more places within China. At the end of 1970s, the area of farmlands on which micro-nutrient fertilizer was applied totaled only a bit more than 100 thousand hectares. In1992, however, the area had extended to 8 million hectares. The main types of micro-nutrients in China includes Z, B, Mo, Mn, Fe and Cu. The application of micro-nutrients is welcome by peasants for small quantity of application, little burden of investment, striking effect of output increment and simple operation. However, farmers  should be cautious that over-fertilization of micro-nutrients incurs contamination very easily.

        According to a research conducted by Institute of Agricultural Resources and Agricultural Zoning under the Chinese Academy the use of organic fertilizers rose by one-fourth from early 1980s to early 1990s but its proportion to total fertilizer use kept going down because the increasing rate of mineral fertilizer input was six times that of organic fertilizer. Due to the development of animal husbandry, the proportion of livestock manure to total organic fertilizers showed a slight increase, but green manure input showed a sharp reduction of 42% during the 10 years under consideration. The reason is poor benefit of planting green manure crops. In China, the area of green manure crops decreased from 7,538 *10⁶ hm² in 1980 to 4.4081* 10⁶ hm² in 1990, a reduction of 41.5%. China is famous for its intensive and meticulous agriculture, and to plant green manure crops has even been an important approach to supplement soil organic matter. Especially, in South China, a long history of winter tillage and rich species resource of green manure crops constitute a strong argument to disseminate the tradition of planting green manure crops to provide more organic fertilizer source.

      In 2000, the nutrient requirements (this refers to effective composition) of China crop will total 34.307 million ton, among which nitrogen 14.533 million ton, phosphorus 5.767million ton and potassium 14.007million ton (in the form of nutrients). The total available nutrient volume provided by organic fertilizers will be 17.563 million. And that provided by mineral fertilizers will be 31.8million ton, 5.3 million ton of which will have to depend upon import. Then, domestic production will provide 18.5 million ton of nitrogen, 8.7million ton phosphorus and 4.6 million ton potash fertilizers. China will import 1.3 million ton phosphorus and 4 million-ton potash nutrients for supplement. Thus, the proportion of N: P₂O₅: K₂O will be 1:0.47:0.25. Prediction indicates that there will be a big surplus for nitrogen and phosphorus nutrient on farmlands of 2000 China, which will reach 10.663 million ton and 6.048 million ton respectively. But the deficit volume of potash will amount to about 1.655 million ton.