[1] Univ Maryland, Dept Geog Sci, College Pk, MD 20742 USA
[2] George Mason Univ, NSF Spatiotemporal Innovat Ctr, Fairfax, VA 22030 USA
[3] Wuhan Univ, Sch Remote Sensing & Informat Engn, Wuhan 430079, Peoples R China
[4] Eastern Michigan Univ, Dept Geog & Geol, Ypsilanti, MI 48197 USA
[5] Inner Mongolia Forestry & Grassland Monitoring &, Inner Mongolia Key Lab Remote Sensing Grassland &, Hohhot 010020, Peoples R China