Regional differences of vegetation cover in the BeijingTianjin sandstorm source region from 2000 to 2015
LI Qingxu,ZHANG Biao,WANG Shuang,XIE Gaodi
Earth Science Frontiers . 2018, (5): 298 -304 .  DOI: 10.13745/j.esf.sf.2018.4.19