The reflectance of six vegetated areas was tracked from spring through early summer and early fall using three dates of ground-reflectance calibrated AVIRIS data sets acquired in 1989. Annual vegetation types exhibit green vegetation spectral features in the spring. The annual plants are largely senesced by early summer and have decreased chlorophyll pigment and leaf water absorption. With the loss of leaf water, lignin-cellulose absorptions emerge at 2.09 and 2.27 jim. AVIRIS spectra from two forest types show a slight increase in the magnitude ofthe chlorophyll red edge in early summer when compared to the spring data. In the early fall data there is a major decline in the magnitude of the chlorophyll red edge and leafwater absorptions at 0.95 and 1.15 jim in tree and shrub dominated areas in drought induced dormancy or undergoing senescence.
Abstruct-An intelligent system (SEIDAM -
System of Experts for Intelligent Data Management) isbeing developed for answering queries about the forests and the environment through the integration of imaging spectrometer data, geographic information, models and field measurements. The imaging spectrometer portion of SEIDAM consists of an hierarchical group of expert systems which control image analysis and GIS software. The complexities for this integration can be reduced by making use of casebased reasoning. Only the data needed to answer the query will be used. The aim of case-based reasoning is to avoid having to build a solution to a problem from first principles, or by drawing on rare expertise, by adapting a known solution for an old problem to the new problem. A case, in this context, consists of a query and an example of the process (plan) that answers that query using an AVIRIS data set, and geographic information, such as forest cover, topography, hydrology, etc. Knowledge about objects acquired by the planner can be used to assist a casebased reasoner during both its retrieval step and its adaptation step. The visualization of 220-channel imaging spectrometer data for forest object delineation is shown.
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