Effects of human disturbance on species diversity of Phoebe zhennan communitis in Jinfengshan Moutain in western Sichuan Community Composition and Structure of Phoebe zhennan Forest in Enshi, Hubei Province Growth and Photosynthesis of Phoebe zhennan Polyembryonic Seedlings under Different Fertilizer Levels Investigation on Wild Resource of Valuable Timber Tree Phoebe zhennan (Lauraceae) Seasonal dynamics of soil N pools under Phoebe zhennan, Cunninghamia lanceolata(Lamb.)and evergreen broad-leaved forests in Dujiangyan Region, Sichuan, China Fine Root Morphology and Biomass of Phoebe zhennan Provenance Seedlings Effect of Fertilization on Photosynthetic Physiology and Growth Characteristics of Phoebe zhennan Seedlings