Research On Spectral Characteristics And Cover Change Of Typical Dune Vegetation In Horqin Sand Land

Surface feature spectrum is theoretical base for remote sensing technology, natural objects have different response to electromagnetic waves In some specific bands because of complex interaction of molecular vibration, which determines the differences of spectral reflect curves.it may occur the phenomenon of "different object with the same spectra characteristics" or "same object with the different spectra characteristics".Determine spectrum character can provide theory basis for imaging mechanism and related remote sensing research.Taking agoura ecological experiment stations as a study area, extract typical sand dune vegetation’s spectral parameter of different growing stages on the basic of measured data In the early stagesn flourishing period and withering period,and analyse spectral reflect curves and the difference between "red edge parameters"; ED、SAM、SCF and SID methods are used to acquire different original spectrum、the first derivation spectrum and the second derivation spectrum to analyse.results show:The second derivative spectrum matching recognition effect is best, original spectrum is the worst, SCF methods is better than SAM method,then SID method, ED at last.Analyze the changes of vegetation cover and landscape pattern based on the data of2000、2005and2009,results show that Vegetation cover change is complicated. Different types transform all the time.it Can be summed up in the following three categories:①decreased continuously(very inefficient and high coverage)②increases and then decreases(low coverage)③decreases and then increases(middle coverage):Ecosystem is in good condition.it was just in the process of improving, Landscape diversity change little. it shows characteristic of breaking before neating.