FOREST ECOSYSTEMS IN AN OLD-GROWTH PINE - MIXED HARDWOOD FOREST OF THE CHANGBAI SHAN PRESERVE IN NORTHEASTERN CHINA

Landscape ecosystems of a 60-ha area, representative of the pine - mixed hardwood forest of the Changbai Shan Preserve in Jilin Province of northeastern China, were identified, described, and contrasted. Site-species relationships and successional trends were examined together with a comparison of these ecosystems and species with those of northern hardwood forests of eastern North America. Ecosystem components of physiography, soil, and vegetation were used to distinguish two major ecosystem types. The more widespread ecosystem 1 differed from ecosystem 2 in having a flatter topography and more moist and nutrient-rich soil. The overstory of ecosystem 1 was dominated by Tilia amurensis Rupr., Pinus koraiensis Sieb. & Zucc., Quercus mongolica Fisch. & Turcz., and Fraxinus mandshurica L., whereas that of ecosystem 2 was dominated primarily by Pinus koraiensis and Quercus mongolica. Understory species and ground-cover vegetation also reflected the difference in physiography and soil between the two ecosystem types. Six Acer species were recorded; they occurred primarily in the subdominant overstory and the understory of both ecosystems. Without catastrophic disturbance, succession favors the more shade tolerant species in all layers. Pinus and Quercus are rare in the ground cover and understory. Acer mono Maxim. is much less dominant than its North American counterpart, Acer saccharum Marsh., in their respective mesic ecosystems in the Changbai Shan forest and forests of western upper Michigan. Fagus and Tsuga, characteristic dominants of northern hardwood forests of eastern North America, are absent. The establishment ecology of Pinus koraiensis, a five-needled pine with wingless seeds, in the mixed hardwood forest is discussed.