摘要:依托陕西长武农田生态系统国家野外科学观测研究站十里铺长期定位观测，研究了5种不同氮肥用量(0、45、90、135、180 kg·hm^-2)对冬小麦农田土壤水分及土壤干层动态的影响。结果表明：土壤干层深度大约在50～260 cm之间；施氮量小于90 kg·hm^-2时，增施氮肥土壤耗水强度和干层深度变化较小，而施氮量超过90 kg·hm^-2时，增施氮肥平均土壤耗水强度较大，但干层深度无明显变化，干层厚度增加速度随施氮量增加而增加；丰水年的高降水量在一定程度上可以缓解土壤干燥化，减小干层厚度。

关键词:旱作农田  土壤干层  氮肥  土壤水分

AbstractBasing on the long-term observation data in Changwu County, Shaanxi Provinve, the influence of different nitrogen rates (0, 45, 90, 135, 180 kg·hm^-2) on soil moisture and evolution of dry soil layer in field of winter wheat was studied. The results showed that the depth of dry soil layer was approximately in the range of 50～260 cm. When nitrogen rate was less than 90 kg·hm^-2 the soil water consumption intensity of nitrogen fertilization and the variation of dry layer depth were small; when nitrogen rate exceeded 90 kg·hm^-2, the average soil water consumption intensity of nitrogen fertilization became relatively high, but there was no significant change in dry layer depth. The increase speed of dry layer thickness increased along with the increase of nitrogen rate. The high precipitation in wet years could relieve soil desiccation and reduce dry layer thickness to some extent.

Key wordsdry-land  dry soil layer  nitrogen fertilizer  soil moisture

文章编号： 0258_7106 (2016) 01_0018_15 中图分类号： P618.41 文献标志码：A

改回日期：2015_07_11

基金项目

**通讯作者耿新霞， 女， 1979年生， 助理研究员， 成矿规律研究方向。 Email： gen gxinxia@cags.ac.cn