内蒙古奈曼农田的微气象特征

运用波文比热量平衡法分析了内蒙古奈曼麦田、谷田、大豆田和稻田的微气象特征。结果表明：随着小麦生长趋于旺盛，反射率趋于减小；灌溉大豆田的反射率（０．１９）比无灌溉大豆田的（０．２１）略小；谷田和稻田的反射率分别为０．２１和０．１９。白天的热量平衡中，绝大部分净辐射用于潜热交换；夜里的热量平衡中，净辐射主要由潜热交换补给。随着小麦的生长，净辐射与太阳辐射的比值增大；灌溉大豆田净辐射与净辐射的比值高于无

Micrometeorological Characteristics of Croplands at Naiman,Inner Mongolia

he micrometeorological characteristics of wheat, millet,soybean and paddy fields are analyzed utilizing the Bowen ratio-energy balance method. The results show that: 1)Albedo of wheat field decreases with wheat growth, which is 0. 25 at the enlongation stage, 0. 21 at the boot stage,and 0. 13 at the start of the ripening stage,respectively. Albedo of irrigated soybean field is 0.19 slightly lower than that (0.21) of non-irrigated soybean field. Albedo of millet and paddy fields is 0.21 and 0. 19 respectively. 2) Net radiation over the croplands depends mainly on latent heat flux in daytime,and it is mainly supplied by latent heat exchange at night. 3) Net radiation and its ratio to solar radiation increases with growth of crops.