不同控释肥类型及施肥方式对肥料利用率和氮素平衡的影响

采用草莓盆栽试验研究了3种肥料类型（普通肥料、控释氮肥、控释复合肥）及其不同施肥方式对氮磷钾利用率、氮素在土壤一作物体系中的平衡及草莓生长的影响。结果表明，相对于普通肥料、控释氮肥和控释复合肥提高了土壤中有效养分的含量，促进了草莓生长，提高了草莓糖酸比和维生紊C含量。不同肥料类型间，植株干重、草莓产量和氮磷钾利用率大小顺序为：控释复合肥〉控释氮肥〉普通肥料。控释氮肥处理土壤中氮的残留率最高，其次为控释复合肥。氮的损失率大小顺序为：普通肥料〉控释氮肥〉控释复合肥。不同施肥方式间草莓糖酸比和维生素C含量、土壤氮残留率差异不显著。植株干重、草莓产量、氮钾利用率大小顺序为：底施〉混施和侧施〉表施；底施处理的磷素利用率最高，其他处理间差异不显著，氮损失率大小顺序为：表施〉混施和侧施〉底施。

Effects of Different Controlled-release Fertilizers and Different Applying Methods on Fertilizer Use Efficiency and Nitrogen Balance

A pot experiment was conducted to study the effects of controlled release fertilizers applied in different position on yield and quality of strawberry,N,P,K use efficiency and nitrogen balance.The results showed that the controlled-release fertilizers improved the changes of available N,P,K contents in soil,promoted the growth of strawberry and increased sugar/acid ratio and the Vc content of the fruit.Dry weight of plant,yield of fruit,N,P,K use efficiency were in the order of controlled release compound fertilizer(CRCF)>controlled release nitrogen fertilizer(CRNF) >common fertilizer(CF).Nitrogen residual ratio was in the order of CRNF >CRCF>CF and N loss ratio was in the order of CF >CRCF>CRNF.There were no marked differences on sugar/acid ratio,the Vc content and N residual ratio with different methods of fertilizer application.Dry weight of plant,yield of fruit,N,K use efficiency were in the order of underneath application>side application and mix application>surface application.The P use efficiency with underneath application was significantly higher than other three treatments,and there was no significant difference among other three treatments.Nitrogen losses ratio was in the order of surface application>side application and mix application>underneath application.