Spectrum characteristic interpretation of wetland vegetation based on detrended canonical correspondence analysis ordination in Wild Duck Lake

Relating the characteristics of vegetation surface features to patterns of reflectance is a vital stage in the interpretation of remotely sensed imagery. This study applied the survey of communities, and the spectrum characteristic measuring, the detrended canonical correspondence analysis (DCCA) to analyze the relationships of community types and its spectrum characteristic in Wild Duck Lake,China. The results are as follows: the DCCA expresses the gradients and the variation characteristics of the community structure and spectrum curve. The first DCCA axis represent variation in blue-green reflectance, and the second DCCA axis represent variation in near infrared reflectance. The diagonal of the DCCA represent the community types gradients, representing the space variation of submerged hydrophyte, free-floating hydrophyte, Ochtholydrophyte, hygrophyte and alttophyte. The spectral data are converted to simulate a GEOEYE-1 banset and corresponding band combination. There are significant relationship between vegetation space pattern and the gradient of ND12 and R14. The sensitivity of vegetation index to vegetation gradient are Normalzed vegetation index, Ratio vegetation index and Difference vegetation index.