贺兰山东麓酿酒葡萄产区砾质砂土速效养分淋溶分析

Available Nutrients Leaching Analysis on Gravelly Soil of Vine Grape Producing in Eastern Foot of Helan Mountain Area

针对贺兰山东麓酿酒葡萄产区砾质砂土土壤砂性但大水漫灌导致养分流失严重等问题，采用室内土柱模拟法，分别设置4种肥料：尿素（20kg／667m2），磷酸一铵（10kg／667m2），硝酸钾（18kg／667m2），硫酸铵（45kg／667m2）；4个土柱高度：20、40、60、80cm；2次灌水量：100、50m3／667ms，用于研究速效养分淋溶规律。结果表明：铵态氮淋溶量较小，20cm土柱最大，占养分投入量在1．04％～1．87％；硝态氮淋溶量较大，分布于各土层，80cm土柱占养分投入量最大达28．82％；尿素态氮淋溶主要集中在40cm土柱，占养分投入量比值与硝态氮相近；速效磷淋溶量较小，主要分布在20cm的土柱，占养分投入量比值14．90％。钾素淋溶量较大，其中80cm土柱淋溶量占总养分投入量的33．81％。总体上，铵态氮淋溶速率较慢，且主要集中在表层土壤，其它养分淋溶速率较快，硝态氮与速效钾各层淋溶量相当。

Serious nutrients loss occurs in vine grape producing areas in eastern foot of Helan Mountain due to gravelly sand soil properties and furrow flood irrigation. Indoor soil column simulation method was adopted to study the nutrients leaching quantities in the sandy soil. Four kinds of fertilizer, urea （20 kg/667m2 ）,anamine phosphate （10 kg/667m2 ）, potassium nitrate （18 kg/667m2 ）,ammonium sulfate （45 kg/667m2 ） were add in 4 soil column height,20 cm,40 cm,60 cm,80 cm respectively. 2 times irrigation amount,100 ma/667m2 and 50 m3/667m2 were added one after another to imitate field irrigation condition. The results showed that less ammonia nitrogen was leached because the largest leaching quantity appeared in the 20 cm soil column only account for 1. 04% to 1.87% of added NH4-N. However,much nitrate loosed 28. 82% of inputs nitrate was leached out of the 80 cm soil column. Urea, has good water solubility, was easy leached the same quantity with nitrate and mainly concentrated in 40 cm soil column, 14. 90% available phosphorus was leached,mainly distributed in 20 cm of soil column. Water soluble potassium leaching amount was also larger,33. 81% of inputs of it was found in 80 cm soil column. On the whole, ammonium nitrogen leaching rate was small, and mainly concentrated in the surface soil,but other nutrients especially nitrate nitrogen and available K leached quickly.