设施蔬菜土壤团聚体中有效磷的分布特征

Distribution characteristics of available phosphorus in different size soil aggregates of greenhouse vegetables

以山东寿光设施蔬菜土壤为材料,采用干筛分法,研究了不同施肥、不同灌溉及不同种植年限影响下土壤团聚体中有效磷的分布特征。结果表明:土壤团聚体中有效磷含量随有机肥施用而显著增加,施用干燥的小麦秸秆和施用农民传统有机肥平均可增加3.2%和14.4%;非根区有效磷含量平均高于根区的8.5%,粒径为0.25～0.50 mm的土壤团聚体中有效磷含量要高于其他粒径;滴灌处理的各土壤团聚体有效磷含量比传统漫灌处理高25.8%;设施种植年限越长,各粒径土壤有效磷积累越多,连作8年以上更加明显;有效磷主要积累于表土层,0～20 cm土层的有效磷平均含量是20～40 cm土层的2倍。研究结果为合理施肥、有效指导设施蔬菜生产提供理论和实践依据。

The distribution characteristics of available phosphorus content in different size soil aggregates under different fertilization treatment, irrigation treatment and planting years treatment were studied by airy sieving nethod, and the tested soils were taken from greenhouse vegetables fields of Shouguang, Shandong province. The results indicated that available phosphorus content in different size soil aggregates increased significantly with organic fertilizer appling, and the application of dried wheat straw and traditional organic fertilizer increased the average available phosphorus content by 3.2% and 14.4% respectively. The average available phosphorus content in non-root zone was 8.5% higher than that of the root zone, and the average available phosphorus content in the size of 0.25-0.50 mm soil aggregate was slightly higher than that of other sizes. The available phosphorus content in different size soil aggregates under dripping irrigation treatment was 25.8% higher than that of traditional flowing irrigation treatment. The available phosphorus increased with cropping years of greenhouse vegetables increasing, and after eight years of continuous planting was more obvious. The average phosphorus content mainly accumulated in the surface soil layer, and the average content of available phosphorus in 0-20 cm soil layer was two times more than that of 20-40 cm soil layer. The results provided scientific basis for enhancing the ability of keeping soil phosphorus in greenhouse vegetables field, improving phosphorus utilization rate, reducing phosphorus loss, and preventing controlling the environmental pollution.