Identifying potential strategies in the key sectors of China's food chain to implement sustainable phosphorus management: a review

摘要

High extraction of phosphate reserves and low phosphorus utilization efficiency in the food chain in China result in large P losses and serious environmental pollution. The P fertilizer industry, soil P surplus, livestock manure P and wastewater P recycling have been identified as the priority sectors based on summarizing several systemic and in-depth reviews of P flows analysis. Mineral P fertilizer production has reached 7.4 Mt P in 2012, which is more than seven times the value in 1980. The large P surpluses in arable land resulted in soil P accumulation of up to 64 Mt during the period 1951-2010. Livestock numbers have increased dramatically (more than ten times) during the period 1949-2012 in China, especially pigs and poultry, and so has the quantity of manure that they produce. The average loading of manure P on arable land in China has increased significantly from 9.5 kg P ha(-1) in 1980 to 20.4 kg P ha(-1) in 2010. Up to 0.49 Mt of wastewater P discharged without treatment also exerted great pressure on the environment in 2012. Based on an understanding of P interactions in these key sectors, an integrated set of policy options and technical measures is proposed. Taking P flows in China in 2010 as an example, if all of the strategies recommended in this study are adopted in P management, about 4.3, 2.5, 1.6 and 0.3 Mt of P resources, respectively, will be saved in the P fertilizer industry, arable land production, livestock manure and wastewater sectors.