Effects of an applied nitrogen form on nitrogen uptake by grasses in simulated grazing pasture
2001
Saigusa, M. (Tohoku Univ., Sendai (Japan)) | Taki, N. | Shibuya, K.
Effects of an applied nitrogen form on the nitrogen uptake by grasses, undergoing frequent cutting in grazing pasture was studied with 15N-labeied fertilizer. Applied ammonium sulfate (AS)-nitrogen was absorbed by grass just after the application and this resulted in a high yield at the first cutting. On the contrary, applied controlled availability fertilizer (CAF) nitrogen was absorbed by grass mainly grown in the summer and autumn, and resulted in a yearly stable yield. The recovery rates for AS nitrogen applied in the spring in 1995 and in 1996 were 48% and 57% respectively whereas the nitrogen applied in the autumn in 1996 was 51%. On the other hand, recovery rates for CAF nitrogen applied in 1995 and in 1996 were 41% and 47%, respectively, and those in the two fold CAF plot were 41% and 29%.
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