坡地植物反射高光谱影响因子分析

在坡地植物遥感监测过程中，很多相关因素的变化会对监测结果产生不容忽视的影响。本文对坡地植物的坡度、坡向、探测天顶角以及不同植物类型等因素进行了分析。为了加强理论探讨，研究在实验室条件下进行，并对均匀坡坡地植物进行了模拟。通过试验发现这些因素对植物高光谱遥感都有影响。当仅坡度变化时，在0°～36°坡度范围内，坡地植物反射比随坡度增大而先增大后减小;当仅探测天顶角变化时，随着探测天顶角的增大，坡地植物在可见光波段光谱特征变化并不明显，在近红外波段反射比逐渐减小;当仅坡向变化时，坡面越转向迎光方向，坡地植物反射比越大，且以入射面与坡面的垂直交线为轴，轴两侧坡向植物叶片反射比基本成对称分布;另外，不同植物类型其光谱曲线有较大差异，即植物类型的差异同样会对坡地植物高光谱遥感产生影响。本研究突破了传统遥感垂直收集数据的局限，利用多角度、高光谱信息进行坡地植物光谱特性分析。坡地植物的高光谱遥感研究对定量遥感的发展有一定的理论意义，同时对植物遥感监测有一定的应用价值。

Analysis of Related Factors of Slope Plant Hyperspectral Remote Sensing

In the present paper, the slope gradient, aspect, detection zenith angle and plant types were analyzed. In order to strengthen the theoretical discussion, the research was under laboratory condition, and modeled uniform slope for slope plant. Through experiments we found that these factors indeed have influence on plant hyperspectral remote sensing. When choosing slope gradient as the variate, the blade reflection first increases and then decreases as the slope gradient changes from 0° to 36°; When keeping other factors constant, and only detection zenith angle increasing from 0° to 60°, the spectral characteristic of slope plants do not change significantly in visible light band, but decreases gradually in near infrared band; With only slope aspect changing, when the dome meets the light direction, the blade reflectance gets maximum, and when the dome meets the backlit direction, the blade reflectance gets minimum, furthermore, setting the line of vertical intersection of incidence plane and the dome as an axis, the reflectance on the axis’s both sides shows symmetric distribution; In addition, spectral curves of different plant types have a lot differences between each other, which means that the plant types also affect hyperspectral remote sensing results of slope plants. This research breaks through the limitations of the traditional vertical remote sensing data collection and uses the multi-angle and hyperspectral information to analyze spectral characteristics of slope plants. So this research has theoretical significance to the development of quantitative remote sensing, and has application value to the plant remote sensing monitoring.