摘要
基于整个水稻生长期内天然降雨径流的田间试验,研究不同施磷水平(0,30,75,150kg/hm2)对水稻田径流磷素的组成形态及损失量的影响。结果表明,不同施磷量在水稻生长初期,对径流中不同形态磷浓度的影响较大,且随着施磷量的增加,不同形态磷的浓度都在增加,但增加幅度最大的是溶解态总磷(DP)和溶解态无机磷(DIP)浓度,即DP/TP从27.9%增加到43.7%,表明施磷肥能促进水稻田磷素径流DP的流失;DIP/DP从46.2%上升到64.2%,而DOP/DP从51.8%下降到35.8%,说明磷肥能增加水稻田磷素径流DIP浓度;颗粒态总磷(PP)占总磷(TP)56.3%～72.1%,表明所有施磷处理中径流携带的磷均以PP为主。在整个植稻期内,产生了6次径流,但水田径流磷素的流失主要发生在第一次,即施肥后不久,可见施肥与径流发生的时间间隔是决定径流磷素损失的重要因素。
The effects of different phosphorus levels （0,30,75,150 kg/hm^2） on P forms and loss in runoff from rice field were studied based on field experiments by natural rainfall runoff,which were during rice growing period.The results indicated that there was an obvious effect of different phosphorus levels on P forms in runoff during initial stage of rice field.The concentration of different P forms increased as P application rates increased.The ratio of dissolved phosphorus to total phosphorus （DP/TP） increased from 27.9% to 43.7%,which showed that P application could accelerate loss of DP in runoff.The ratio of dissolved inorganic phosphorus to total phosphorus （DIP/TP） increased from 46.2% to 64.2%,which indicated that P application could increase loss of DIP in runoff.Particle P （PP） was t he primary P form in the runoff,comprising 56.3%-72.1% of the TP.There was six runoff processes during rice growing period.But P loss mainly occurred in the first time,soon after the fertilizer application.Therefore the time interval between fertilizer application and runoff generation was an important factor to control P loss.
出处
《水土保持学报》
CSCD
北大核心
2010年第5期31-34,共4页
Journal of Soil and Water Conservation
基金
国家自然科学基金项目(40371111)
中国博士后科学基金项目(20090451442)
关键词
施磷
水稻田
径流
磷素流失形态
phosphorus application
rice field
runoff
p forms
