Parasphenopteris Sun & Deng, a new genus from the Lower Permian of Wuda, Nei Mongol, China Analysis of relationships among leaf functional traits and economics spectrum of plant species in the desert steppe of Nei Mongol Colonization of arbuscular mycorrhizal fungi and dark septate endophytes in roots of desert Salix psammophila Carbon storage of the forests and its spatial pattern in Nei Mongol, China Temporal Spatial Variances of Holocene Precipitation at the Marginal Area of the East Asian Monsoon Influences from Pollen Evidence