Spectral, spatial and temporal characteristics of Arctic tundra reflectance
Spectral, spatial and temporal characteristics of Arctic tundra reflectance
复制标题
北极苔原反射率的光谱、空间和时间特征
DOI：
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发表时间：
1993
期刊：
影响因子：
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通讯作者：
A. Hope
中科院分区：
文献类型：
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作者：
D. Stow;B. Burns;A. Hope
摘要本文的目的是量化和分析在阿拉斯加北方的布鲁克斯山脉山麓的一个研究地点，北极苔原植被反射的太阳辐射的光谱、空间和时间变化。光谱辐射数据从手持辐射计和SPOT HRV传感器采样沿着山坡样带（toposequencies）和四个植被群落类型。沿着地形序列的归一化植被指数（NDVI）的空间趋势对应于丰富的绿色植被物质和植被组成的变化。一个显着的时间增加的NDVI发生沿着的地形序列从生长季节开始（6月中旬）的峰值绿色了（7月底）。三个苔原优势植被群落，干燥的石楠，潮湿的草丛和潮湿的莎草，光谱特征是中等分离，干燥的石楠是最可分离的。在整个生长过程中，主要群落类型的整体可分性是相似的。
Abstract The objective was to quantify and analyse the spectral, spatial and temporal variability of solar radiation reflected from arctic tundra vegetation at a study site in the Brooks Range foothills of northern Alaska. Spectral radiance data from hand-held radiometers and the SPOT HRV sensor were sampled along hillslope transects (toposequences) and within four vegetation community types. The spatial trend of normalised difference vegetation index (NDVI) along the toposequences corresponded to variations in the abundance of green vegetation matter and in vegetation composition. A marked temporal increase in the NDVI occurred along the toposequences from the beginning of the growing season (mid-June) to peak green up (end of July). The spectral signatures of three tundra dominant vegetation communities, dry heath, moist tussock and wet sedge, were moderately separable, with dry heath being most separable. The overall separability of the major community types was similar at all times during the growing ...