设施农业土壤磷素富集的动态变化

Study on dynamics variation of phosphorus enrichment in greenhouse agricultural soil

为了找出设施农业土壤磷素富集的动态变化规律,对陕北地区不同种植年限的设施农业土壤0-40cm土层及剖面磷素含量的动态变化进行了研究。结果表明：土壤全磷、有效磷、无机磷、有机磷含量在不同的种植年限及土层上形成了显著差异,在设施农业环境条件下,长期大量施用磷肥不仅使0-20 cm耕层土壤磷素大量富集,20-40 cm土层磷素也均有不同幅度增加;随着设施农业种植年限的延长,全磷、有效磷和有机磷都以不同的增加幅度和增加量逐年增加,随土层的加深逐渐递减;在各形态无机磷中,Ca2-P、Ca8-P、AL-P、Fe-P、O-P、Ca10-P分别占无机磷总量9.74%、22.18%、6.54%、5.86%、18.02%、37.66%;随着种植年限的延长,Ca2-P、Ca8-P、AL-P、Fe-P、O-P、Ca10-P含量都有不同程度的富集,主要以磷酸钙盐（包括Ca8-P、Ca10-P、Ca2-P型）的形态积累在不同土层中。

In order to find out the dynamics law of agricultural greenhouse soil＇s phosphorus enrichment,study was made on dynamics variation of phosphorus content in agricultural greenhouse soil at different cultivation ages from 0～40 cm in Northern Shaanxi.The results showed that there was a significant difference in the content of total phosphorus,available phosphorus,inorganic phosphorus and organic phosphorus in agricultural greenhouse soil between different cultivation ages and different soil layers under the greenhouse agricultural circumstances.In greenhouse agriculture,a large amount of long-term application of phosphate fertilizer not only made the phosphorus in the topsoil from 0～20 cm enrich significantly,but also made the soil phosphorus increase at different degrees in the soil layer from 20～40 cm.With the prolongation of cultivation ages in greenhouse agriculture,total phosphorus,available phosphorus and organic phosphorus increased in different amount and extent year by year, but decreased with the increment of the soil depth.Among all types of phosphorus,Ca2-P,Ca8-P,AL-P,Fe-P,O-P and Ca10-P occupied 9.74%,22.18%,6.54%,5.86%,18.02% and 37.66% of the total amount of inorganic phosphorus,respectively.Moreover,with the prolongation of cultivation ages,the content of Ca2-P,Ca8-P,AL-P,Fe-P,O-P and Ca10-P enriched at different degrees,and accumulated in the form of calcium phosphate（including Ca8-P,Ca10-P and Ca2-P） at different layers of soil.In conclusion,we find the dynamics law of agricultural greenhouse soil＇s phosphorus enrichment and its relationship with the planting ages,which provides an important basis for the effective utilization of the accumulative phosphorus in agricultural greenhouse soil and reasonable application of phosphate fertilizer.