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Phosphorus is not only the flora and fauna necessary nutrients, is also an important factor of environmental pollution. Reveal the circulation and flow rule of phosphorus in farmland - livestock - Nutrition - Environment system is a precondition for phosphorus nutrient management. Phosphorus cycling and balance generally pay more attention to farmland, very little research system for livestock and household nutrition. Proceed from the perspective of farmland, livestock and human nutrition, environment, research the phosphorus nutrition system flow and circulation, and thus provide the basis for phosphorus nutrient management. Of farmland - livestock - Nutrition - Environment system is divided into plant production systems, animal production systems, feed processing, food processing systems, home systems, wastewater treatment systems and solid waste disposal system, and then analyze each subsystem phosphorus prime flow characteristics that determine the phosphorus input and phosphorus output items. Access to literature of various parameters, such as crop grain, the phosphorus content of animal products, according to statistics in 1980, 1990 and 2001 data, the past 20 years Phosphorus Cycling in the current situation evaluation. The results show that from 1980 to 2001, China's farmland ecosystem phosphorus gradually from deficit to surplus, deficit of 3.5 million tons in 1980, a surplus of 1.423 million tons in 1990 to a surplus of 3.711 million tons in 2001. From the the phosphorus nutrition point of view, China's major food crops of rice, wheat phosphorus production efficiency, wheat processing into flour the phosphorus production efficiency 40.0%, only 13.2% of the phosphorus in rice processed into rice production efficiency. Diet, the 20 years from 1980 to 2001, the diet of the Chinese residents of major changes, to move from high grain diet type, plant foods and try the direction of change. 1980 China's consumer the plant foods phosphorus 461,000 tons, 27,000 tons of phosphorus consumption of animal foods, the phosphorus plant foods and animal foods phosphorus ratio of 17.1:1; 2001, China's consumption of plant food phosphorus 524,000 tons, consumption of animal food phosphorus was 11.2 million tons, phosphorus plant food and animal food phosphorus ratio of 4.7:1, compared with 1980, the proportion of plant food phosphorus decreases and the proportion of animal food phosphorus. From the 1980s to the present, the past 20 years, the number of China's grain increased, the rapid development of animal husbandry, growing urban population, urbanization rate increased significantly, which are closely related to the phosphorus flows and ecological environment. 1980, 1990 and 2001, agricultural discharges to the environment phosphorus is 22.8 million tons, 22.0 million tons, 29.9 million tons; livestock systems phosphorous discharges to the environment are 460,000 tons, 812,000 tons, 117.7 million tons; family system phosphorous discharges to the environment is 5.8 million tons, 12.2 million tons, 26.1 million tons; various subsystems of total phosphorus discharged to the environment is 74.6 million tons, 1.154 million tons and 1.737 million tons. The largest proportion of animal production systems in each subsystem phosphorus discharged to the environment accounted for the entire nutritional system phosphorus releases to the environment, 1980 was 62.5%, and 71.8% in 1990, 69.7% in 2001. Family phosphorus proportion of discharges to the environment increased rapidly, from 6.1% in 1980, increased to 11.0% in 2001. Description of the development of animal husbandry in China and improve the level of urbanization increased phosphorus releases to the environment.
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