雪中污染物对积雪光谱的影响研究

Analysis on the spectral reflectance response to snow contaminants in Northeast China

分析了积雪光谱与其中污染物含量的关系.研究发现随污染物含量的增加,350～850nm处积雪的反射率急剧降低.用非线性回归方法,对污染物含量敏感的波长进行分析.结果显示,在384nm处,随污染物含量的增加,反射率以对数的形式变小;而在1495nm处,随污染物含量的增加,反射率以指数的形式增加.同时从所测光谱中,选择TM各个波段的中心波长与污染物进行相关分析,得到和逐波段与污染物进行相关分析一致的趋势,因此可以将该方法结合TM影像来预测积雪中污染物的含量.

We have analyzed the relationship between the snow spectrum and snow contaminants.It is found that from 350nm to 850nm snow reflectance dramatically decreases with increase in concentrations of contaminants in snow.The results show that snow reflectance at 384nm logarithmically decreases with increase in the snow contaminants while the reflectance at 1495nm exponentially increases with the snow contaminants.Besides,we have selected six bands according to the center wavelength of TM to analyze the relation between snow reflectance and snow contaminants,and we come to the same conclusion as from the hyperspectral analysis.Therefore,this method can be used in combination with TM image to forecast the contaminants in snow.