摘要
１ＩｎｔｒｏｄｕｃｔｉｏｎＴｈｅａｒｅａｏｆｒｅｄｓｏｉｌｓｉｎＣｈｉｎａｃｏｖｅｒｉｎｇａｂｏｕｔｍｏｒｅｔｈａｎ２ｍｉｌｉｏｎｋｍ２ａｃｃｏｕｎｔｓｆｏｒ２２．７％ｏｆｔｈｅｗｈｏｌｅｃｏｕｎｔｒｙ’ｓａｒｅａ．［１］Ｍｏｓｔｏｆｔｈｅｒｅｄｓｏ...
The influence of fertilization with urea and ryegrass on nitrogen utilization and transformation in red soil has been studied by using 15 N tracer method. When urea and ryegrass were applied alone or in combination, the percentage of N uptaken by ryegrass from labelled urea was 3 and 1.7 times that from labelled ryegrass for the application rate of 200 mgN·kg -1 and 100 mgN·kg -1 , respectively; combining application of ryegrass and urea reduced uptake of urea N and increased uptake of ryegrass N by ryegrass plant, but the percentage of N residued in soil increased for urea and decreased for ryegrass; when urea and ryegrass were applied alone, the percentage of N residued in soil from labelled ryegrass was more than 69% while that from labelled urea was less than 25%, and much more ryegrass N was incorporated into humus than urea N.
关键词
红色土壤
氮
尿素
麦草
Nitrogen, Utilization, Transformation, Red soil, Ryegrass
