沟灌夏玉米棵间土壤蒸发规律研究

Soil Evaporation of Summer Maize in Furrow Irrigation

采用两种规格的微型棵间蒸发皿 (Micro-Lysimeter)分别测定沟灌夏玉米田沟、垄土面蒸发 ,对沟灌条件下夏玉米棵间土壤蒸发与作物蒸腾变化规律进行了试验研究 ,分析了相对土面蒸发强度与土壤含水量的关系以及土面蒸发强度与作物叶面积指数的关系。结果表明 ,沟灌条件下夏玉米田棵间土壤蒸发量占全生育总耗水量的 33.0 %～ 34.5 % ,棵间土面相对蒸发强度与表层土壤含水率和作物叶面积指数之间均呈现良好的指数函数关系 ,灌溉或降雨后 2～ 3d内土面蒸发强度较大 。

Soil evaporation in field ditch and on ridge was measured by using two kinds of micro-lysimeters respectively.The change of soil evaporation and crop transpiration in summer maize under furrow irrigation were studied,and the relationship between relative soil evaporation intensity and soil water content,and the relationship between soil evaporation intensity and leaf area index were analyzed. The results showed that soil evaporation in summer maize field under furrow irrigation condition accounted for 33.0%～34.5% of water consumption in the whole growth period, and there was a good exponential function relationship between relative soil evaporation intensity and surface soil water content and leaf area index. Soil evaporation intensity was comparatively great within 2～3 days after irrigation or rainfall, and it was evidently influenced by atmosphere evaporation intensity.