呼伦贝尔草原植被覆盖度估算的光谱模型

Spectral models for estimating grassland vegetation coverage on Hulunbeier Grassland, Inner Mongolia, China

采用美国ASD公司Fieldspec3光谱仪和日本富士数码相机,于2009年7～8月在内蒙古呼伦贝尔草原区进行了植物高光谱和植被覆盖度测定,并运用回归分析方法,建立实测归一化植被指数(ASDNDVI)和植被覆盖度之间的地面光谱模型,分析MODIS/TERRA卫星的NDVI(MODISNDVI)与ASDNDVI的关系,建立预测植被覆盖度的MODIS光谱模型,并对模型进行精度检验.结果表明所建的MODIS光谱模型是线性函数,该模型预测精度高于亚像元分解模型,标准误差为11.58%,平均预测精度达到88.75%.

During July and August 2009, an ASD Fieldspec3 spectroradiometer and a Japanese Fuji digital camera were used to measure hyperspectral data and vegetation coverage on the Hulunbeier Grassland, Inner Mongolia, China. Regression analysis methods were used to establish a ground spectral relationship between the local measured vegetation coverage and normalized difference vegetation （ASD NDVI）. Then, the relationship between NDVI got from MODIS/TERRA （MODIS NDVI） and ASD NDVI was analyzed to establish a MODIS Spectral Model to estimate vegetation coverage with MODIS NDVI. Finally, the accuracy of MODIS spectral model was validated. The MODIS Spectral Model was just a linear equation but had higher prediction accuracy than sub-pixel models with 11.58% standard error and 88.75% average prediction accuracy.