关键词: 荒漠植物, 生物量, 估算, 冠丛特征

Abstract: By using measured hyperspectral data, the spectral characteristics of the water body in Dianchi Lake were analyzed, and a hyperspectral inversion model for the chlorophyll-a concentration in the Lake was established by statistical methods. Based on the spectral characteristics and the merged MODIS images by HSV transformation, the distribution of chlorophyll-a concentration in the Lake was monitored. It was shown that the spectral reflectance peaks of the water body were near 550 and 700 nm, and the positions and values of the peaks were very sensitive to the changes of chlorophyll-a concentration. The higher the chlorophyll-a concentration, the closer the values of the two peaks, and the reflective peak near 550 nm had an excursion to short wave while that near 700 nm had an excursion to long wave. Therefore, the difference between the values of spectral peaks near 550 and 700 nm could be used as the parameter in establishing a model for inversing chlorophyll-a concentration, and the estimation could have a higher precision. Our results indicated that the MODIS false color images achieved by HSV transformation and merging technologies could visually inverse the spatial distribution of chlorophyll-a concentration in Dianchi Lake.

Key words: Desert plant, Biomass, Estimation, Crown characteristic