论文部分内容阅读
INTRODUCTION There is a close relationship between the transformation of fertilizer-N and the statusof nitrogen nutrition in rhizosphere soils.Previously,Harmsen and Jager(1962)made ananalysis of N and C contents in the rhizosphere soils of upland crops and found thatclose to the root zone there was an enrichment of these substances.Recently,Qin and Liu(1984;1989)investigated the distribution of nitrogen in the rhizosphere of crops after ap-
INTRODUCTION There is a close relationship between the transformation of fertilizer-N and the status of nitrogen nutrition in rhizosphere soils. Previously, Harmsen and Jager (1962) made an analysis of N and C contents in the rhizosphere soils of upland crops and found thatclose to the root zone there was an enrichment of these substances. Recently, Qin and Liu (1984; 1989) investigated the distribution of nitrogen in the rhizosphere of crops after ap-