Consumption of fertilizer
In general, chemical fertilizers were not widely used before 1950. In China, chemical fertilizers were not used until they were imported at the beginning of this century, though Chinese peasants have always been highly skilled in the applications of manures (Weixin, 1991). The use of chemical fertilizers started really to rise after 1949. In 1952, China consumed only 78 kton fertilizer (expressed as N, P2O5 and K2O), which corresponds with 0.6 kg per ha sown. Some thirty years later it has increased up to 120 kg/ha in 1985. Undoubtedly, it was the result of China's rapid industrial growth during the last decades, together with the great importance given to Chinese agriculture (Weixin, 1991).