玉米地组分亮度温度分类变化研究

Study on the Classification of Component Brightness Temperature Over a Maize Canopy

以玉米整个生长期野外热红外辐射观测数据为基础,对两种组分亮温分类方法作了比较,并对玉米地组分亮温的变化特征展开了分析。结果表明,农田亮温组分的数目和数值随测量时间和日期改变。在整个测量期间,在当地时间中午前后,农田呈现出3个亮温组分植被、被阳光照到的亮土和植被阴影下的暗土。观测早期,植被亮温分布相对集中;随着农田植被覆盖率的增高,植被亮温分布逐步分散,组分间温差缩小,部分亮温值相互重叠。产生这些现象的原因将在以后的研究中加以探讨。

This paper researches on the methodology for brightness temperature component classification and temporal variations of these component values by an in situ experiment dedicated to maize canopy brightness temperature distribution. Results show the number of components and their brightness temperature values vary with time of day and biomass density. Three components of vegetation, sunlit and shaded soil could be identified at midday during the measuring period. When the canopy is highly co-vered, vegetation's brightness temperature has a wider range, and the components are difficult to be distinguished. The interpretation of these phenomena will be conceived in the further research.