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The effects of different chemical fertilizer combinations (N, P and K) on crop yield, N uptake and nitrate distribution and accumulation to a depth of 100 cm were studied in a cinnamon fluvo-aquic soil profile (Beijing) with a continuous winter wheat-summer maize cropping system for nine years. The experiment consisted of 7 treatments: no fertilizer control (CK); N alone, N in combination with K (NK), P (NP), and P and K (NPK and N1PK); and P and K in combination without N (PK). The rate of N was 150 kg ha-1 for the N treatments except Treatment N1PK with higher N rate (195 kg ha-1), and the rates of P (P2O5) and
The effects of different chemical fertilizer combinations (N, P and K) on crop yield, N uptake and nitrate distribution and accumulation to a depth of 100 cm were studied in a cinnamon fluvo-aquic soil profile (Beijing) with a continuous winter wheat- N maize, N in combination with K (NK), P (NP), and P and K (NPK and N1 PK); and P and K in combination without N (PK). The rate of N was 150 kg ha-1 for the N treatments except Treatment N1 PK with higher N rate (195 kg ha-1), and the rates of P (P2O5) and