3Y.LIU. Y.ZHA,J. GAO,S.NI. assessment of degradation near lake Qinghai,West China,using landsat TM and in situ reflectance spectra data [J].International Journal of Remote Sensing.2004,25 (20): 4177-4189.
4Schmidt KS,Skidmore A K.ExPloring spectral discrimination of grass species in African rangelands [J].International Journal of Remote Sensing.2001,22(17) :3421-3434.
5Tueller P T.Remote sensing technology for rangeland management applications[ J ]JoumalofRangeManagement, 1989,42(6):442-53.