中文摘要：

露水是显著地影响植被和小气候环境的生理的地位的水的重要来源。为确定露水事件的特征并且在不同生态系统分析露水形成的内在的机制，我们测量了基于在二农田的露水事件的流动侧面方法，数量，频率和持续时间，在 Zhangye 的干旱人工的绿洲农田，在 Luancheng 的 Gansu 省和 亚humid 农田，在中国的 Hebei 省。结果证明露水事件总共 69 天的被观察在从5月28日的 Zhangye ，说明了59%成长季节，)，当时在 Luancheng 的 128 天，它说明了79%成长季节(从4月5日到2008年9月13日)。露水事件的频率分别地是在 Zhangye 和 Luancheng 的降水的那些的 2.8 和 2.4 次。另外，露水数量在 Zhangye 和 Luancheng 到达了直到 9.9 和 20.2 公里，它分别地说明了 9.5%降水和 4.1% 。露水的平均数量是在 Zhangye 和 Luancheng 的 0.14 和 0.16 公里 / 夜里，分别地并且露水事件的持续时间在二个学习地点从 0.5 ～ 12.0 h 。露水数量与大气的水蒸汽集中和露水持续时间的坡度被联系(P < 0.001 ) 在两个二个地点。结果暗示露水事件每夜里就露水出现频率和数量而言与亚 humid 区域相比在干旱区域在庄稼生长起一个更重要的作用。

英文摘要：

Dew is an important source of water which significantly influences the physiological status of vegetation and the microclimate environment. For quantifying the characteristics of dew events and analyzing the underlying mechanism of dew formation in different ecosystems, we measured, based on the flux-profile method, the amount, frequency and duration of dew events in two croplands, an arid artificial oasis cropland in Zhangye, Gansu province and a sub-humid cropland in Luancheng, Hebei province in China. The results showed that dew events were observed in a total of 69 days in Zhangye, which accounted for 59% of the growing season（from 28 May to 21 September, 2012）, while 128 days in Luancheng, which accounted for 79% of the growing season（from 5 April to 13 September, 2008）. The frequencies of dew events were 2.8 and 2.4 times of those of precipitation in Zhangye and Luancheng, respectively. In addition, the dew amount reached up to 9.9 and 20.2 mm in Zhangye and Luancheng, which accounted for 9.5% and 4.1% of precipitation, respectively. The average amount of dew was 0.14 and 0.16 mm/night in Zhangye and Luancheng, respectively and the duration of dew events ranged from 0.5 to 12.0 h in the two study sites. Dew amounts were associated with the gradient of atmospheric water vapor concentration and dew duration（P＆lt;0.001） in both the two sites. The result implies that dew events play a more important role in crop growth in arid areas in comparison to sub-humid areas considering the dew occurrence frequency and the amount per night.