典型灰漠土棉田土壤无机磷对不同施肥方法响应动态的研究

因为连续多年的施肥,土壤中存在巨大的由固定态磷组成的磷库,通过一定方法使磷库中固定态磷转化为对植物有效的磷对农业和资源环境领域具有重要意义.通过在典型灰漠土棉田进行不同施肥方法的试验,研究在棉花生长条件下整个棉花生育期土壤无机磷组分动态变化,及其与土壤有效磷、棉花产量之间的关系,以探讨激活利用土壤固定态磷的方法.结果表明:(1)肥料类型、施肥量以及施肥方法的变化可以影响典型灰漠土棉田无机磷组分的动态,一定程度上能激活土壤中固定态磷,提高土壤中有效磷的含量.(2)对于典型灰漠土棉田,钾素用量较常规减半、在常规施肥基础上施用50 kg腐殖酸肥料等措施能提高土壤有效磷含量,进而提高磷肥的当季利用率.(3)在灰漠土中,Ca2-P对土壤有效磷贡献最大,是作物的主要磷源,而Ca8-P、Al-P、Fe-P对土壤有效磷也有一定贡献,是作物的缓效磷源,O-P、Ca10-P对土壤有效磷贡献不明显.

Effect of Inorganic Phosphorus Fractions in Typical Cotton Field of Gray Desert Soil on Different Fertilizer Application Methods

Since fertilizer has been applied for many years continuously,there is a huge phosphorus storehouse consisted of fixed phosphate in soil,esp.in gray desert soil of Xinjiang.So activating fixed P is important to agriculture and resources sciences.The paper studied fraction change of soil inorganic phosphorus,relationship between the change and available phosphorus in typical cotton field of gray desert soil.Results showed:(1) Fertilizer type,quantity and fertilization method all could influence fraction change of soil inorganic phosphorus in typical cotton field of gray desert soil,and activated fixed P transform to available P.(2)Only half of potassium content was applied,compared with routine and 50 kg humic acid fertilizer was appied on the basis of conventional fertilizers in typical cotton field of gray desert soil,which could increase available P,then the phosphate fertilizer was enhanced to work use factor.(3) In gray desert soil,Ca2-P was mainly resource of available P,then Ca8-P,Al-P was enhanced and Fe-P were slowly available phosphorus,which also contributed to the soil.O-P,Ca10-P was not obvious to the soil available P contribution.