Growth models of Excentrodendron hsienmu population in a karst seasonal rain forest Megasporogenesis and embryo sac development in Excentrodendron hsienmu (Malvaceae) with reference to the systematic affinities of Excentrodendron Natural regeneration of young Excentrodendron hsienmu in karst mountainous region in Southwest Guangxi,China. Relationship between Plant Diversity and Environmental Factors of Excentrodendron hsienmu Community in Karst Mountains in Pinguo County,Guangxi