【摘要】 通过对不同宽度及其上种豆与否的稻田田埂内外侧0⁶0 cm剖面速效磷浓度及贮量的变化情况监测,分析了田埂宽度与种豆对稻田速效磷可能经田埂侧渗流失的影响。不种豆条件下,田埂宽度由40 cm增厚至50 cm和60 cm,速效磷向田埂外侧迁移,平均可减少2.19 kg hm^-2和2.36 kg hm^-2;种植大豆条件下,田埂宽度增厚至50 cm和60 cm,速效磷可减少2.69 kg hm^-2和5.08 kg hm^-2。田埂上种植大豆可使内、外剖面间速效磷贮量差提高7.9%。尽管大豆吸收有助于降低田埂速效磷浓度,但由于大豆根系会在田埂中造成大孔隙,因此田埂种植大豆时应适当加宽田埂,以减小速效磷侧渗流失风险。田埂中40⁶0 cm土层水分充足,速效磷浓度、贮量均较高,可能是稻田速效磷侧渗流失的主要通道。更多还原

【Abstract】 The effects of paddy bund width and soybean planting on loss of Olsen phosphorus（P） with lateral seepage were studied by monitoring the concentrations and contents of Olsen P in different soil profiles（0- 60 cm） of the paddy bunds. With the width of paddy bund increasing from 40 cm to 50 cm and 60 cm, the loss of Olsen P averagely decreased by 2.19 kg hm^-2and 2.36 kg hm^-2, respectively, in the absence of soybean planting. The corresponding numbers were 2.69 kg hm^-2and 5.08 kg hm^-2, respectively, in the presence of soybean planting. The differences of Olsen P content between inner and outer bunds increased by 7.9% on average in the soybean-planting treatments,compared with non-soybean-planting treatments. Although Olsen P concentration in the bunds decreased with soybean planting, there probably were macropores in the bunds as a consequence of soybean root growth. Therefore, the bund would be widened to reduce the risk of Olsen P loss through paddy bund, when crop was planted on the bund.Because of abundant water and high content of Olsen P, the 40- 60 cm soil layer in paddy bund may be the primary path of Olsen P loss with lateral seepage.更多还原