Detection of Robinia Pseudoacacia Planted Forest Canopy Health Using Landsat ETM Image Data
利用Landsat ETM+数据检测人工刺槐林冠健康

The principal goal of this experiment study was to develop an objective,reliable and simple methodology for detection of Robinia Pseudoacacia Planted forest canopy health using Landsat ETM+ image data which would provide a cost-effective first-level indication of forest canopy health for forest managers.Digital procedures to optimize the information content of Landsat ETM+ image data for detection of Robinia Pseudoacacia planted forest canopy health were described.On the basis of phonological calendar of Robinia Pseudoacacia in the local region,imagery acquired on May 2,2000 was calibrated to exoatmospheric reflectance to minimize sensor calibration offsets and standardize data acquisition aspects,and Band 6 was converted into effective at satellite temperature in Kelvin.Then,a nearly pure artificial Robinia Pseudoacacia forest land was selected as the experimental area.Robinia Pseudoacacia forests were classified into healthy or slight dieback,moderate dieback,dead or severe dieback or shrub and grass lands,non-vegetation land using ISODATA classifier with three types of different band composition such as Band 1~5 and 7 (Group 1),normalized Green and Moisture component of Tasseled Cap transform (Group 2),normalized Green and Moisture component of Tasseled Cap transform and normalized effective at satellite temperature converted from Band 6 (Group 3).The results show that ISODATA classification of Group 3 was more effective method for detection of Robinia Pseudoacacia Planted Forest Canopy Health.