磷肥和钾肥不同配施方式对其养分在土壤中迁移的影响

The Effects of Phosphate and Potash Fertilizers in Diffierent Facilities on Soil Nutrient Migration

采用单点源滴灌试验方法,模拟滴灌条件下磷(P)、钾(K)肥作为基肥一次施入和随水分施入两种不同的配施方式下速效P、K含量在土壤中的时空分布变化情况。结果表明:对于可溶性较好的磷、钾肥作为基肥施入土壤后,均随着滴灌水的下渗运移而发生迁移,速效磷的高值区出现在湿润区的边缘附近,速效钾则比较均匀的分布在湿润区内;随水分施磷肥,仅在湿润区深度20cm,水平方向15cm以内的土层发生积累。在施加磷肥总量一致时,随水分施入土壤速效磷含量的最大值明显高于作为基肥施入的最大值;随水分施钾肥,速效钾在土壤中的分布也趋于均匀,但是在滴水点附近形成高值区,且随水分施钾肥可在一定程度上减缓速效钾在土壤中的迁移速度。

A single-point irrigation installation was used to simulate drip irrigation,where the effects of different fertilization methods on soil nutrient migration were studied.Two application methods of phosphate（P）and potash（K）fertilizers were designed：applied before irrigation as base fertilizer and applied with irrigation water,and the temporal and spatial distributions of soil P and K after drip irrigation were observed.The results showed that the soluble P and K fertilizers were migrated with the infiltration of drip irrigation,and the high value of available P appeared near the edge of the wet zone,while the available K evenly distributed in the moist area.Soil P accumulated only in the wet zone depth of 20 cm and the horizontal direction of 15 cm within the soil caused by the water flow.When the total application amount of P fertilizer was consistent,the maximum content of available P in soil applied with water was significantly higher than that applied as base fertilizer.When applied with water,the distribution of available K in soil was also uniform,whereas high value area was formed near the drip point.Applying K fertilizer with irrigation water could slow down the migration rate of available K to a certain extent.