膜下滴灌棉田土壤磷钾养分空间分布特征

通过对膜下滴灌棉田土壤速效磷钾养分时空分布研究,结果是棉花滴灌水前0~20 cm土层水平方向速效磷钾含量变化波动幅度较大,20~60 cm土层变化幅度较小。滴水后表层土壤速效磷含量变化波动逐渐变小,速效钾含量变化幅度且较大;0~60 cm土层土壤速效磷钾含量自表层垂直向下的分布特点分别是:磷素为10~20 cm>0~10 cm>20~40 cm>40~60 cm,钾素为0~10 cm>40~60 cm>10~20 cm>20~40 cm;随时间变化特点是:耕层土壤速效磷钾含量从苗期开始均上升,到盛蕾期达最大值,盛蕾期后基本呈直线缓慢递减,不同的是棉花吐絮后土壤速效钾含量回升较快。

Space Distribution Characteristics of Phosphorus and Potassium in the Under-film Trickle Irrigation Cotton Field

Though study of space distribution characteristics of soil phosphorus and potassium in under-film trickle irrigation cotton field,it's found that the variety of the content of cotton field soil phosphorus and potassium was: fluctuation was bigger in the horizontal direction in the layers of 0~20cm,while it's smaller in the layersof 20~60cm;phosphorus content fluctuation in the skin soil gradually became small after being trickling and potassium content fluctuation became big;the verdical distribution characteristics of the phosphorus and potassium from the skin layer to the deep layer in 0-60cm layers respectively were: for phosphorus it's 10-20cm>0-10cm>20-40cm>40-60cm;for potassium it's 0-10cm>40-60cm>10-20cm>20-40cm;the characteristics with the time changes were: the content of the phosphorus and potassium in the ploughing layer went up from the seedling stage,and the maximum was reached in the stage of flourishing bud;then slowly decreased,basically straightly;what's different was the content of the phosphorus and potassium rised again rapidly after the opening of bolls.