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This paper introduces the Flexible Global Ocean‐Atmosphere‐Land System Model: Grid‐Point Version 3 (FGOALS‐g3) and evaluates its basic performance based on some of its participation in the sixth phase of the Coupled Model Intercomparison Project (CMIP6) experiments. Our results show that many significant improvements have been achieved by FGOALS‐g3 in terms of climatological mean states, variabilities, and long‐term trends. For example, FGOALS‐g3 has a small (−0.015°C/100 yr) climate drift in 700‐yr preindustrial control (piControl) runs and smaller biases in climatological mean variables, such as the land/sea surface temperatures (SSTs) and seasonal soil moisture cycle, compared with its previous version FGOALS‐g2 during the historical period. The characteristics of climate variabilities, for example, Madden‐Julian oscillation (MJO) eastward/westward propagation ratios, spatial patterns of interannual variability of tropical SST anomalies, and relationship between the East Asian Summer Monsoon and El Niño–Southern Oscillation (ENSO), are well captured by FGOALS‐g3. In particular, the cooling trend of globally averaged surface temperature during 1940–1970, which is a challenge for most CMIP3 and CMIP5 models, is well reproduced by FGOALS‐g3 in historical runs. In addition to the external forcing factors recommended by CMIP6, anthropogenic groundwater forcing from 1965 to 2014 was incorporated into the FGOALS‐g3 historical runs.

The distributions of various forest cover types on Changbai Mountain of northeastern China were examined by interpreting Landsat Thematic Mapper satellite data. The area studied consists of the Changbai Nature Reserve plus an 8 km wide buffer zone. The dominant forest cover types were mixed Korean pine (Pinuskoraiensis Sieb. & Zucc.) hardwood forest below 1100 m above sea level (asl) and evergreen coniferous forest between 1100 and 1650 m asl. These two forest cover types accounted for about 70% of the area inside the reserve, and 50% of the area outside the reserve. Other forest cover types included aspen (Populusdavidiana Dode) –white birch (Betulaplatyphylla Sukachev) forest, hardwood forest, larch (Larixolgensis A. Henry) forest, sparse forest land, and mountain birch (Betulaermanii Cham.) forest. Above the forest line (1950 m asl), a zone of tundra was distributed on the top of Changbai Mountain. The mountain birch forest was located between tundra and the evergreen forest. Human-altered areas, including forest clearcuts and urban areas, accounted for only 10% of the whole study area. More than 90% (in area) of the human-altered areas was found in the zone surrounding the reserve. To better protect the old-growth forest ecosystems inside and outside Changbai Nature Reserve, conservation planning for the reserve and forest management for the surrounding area need to be modified.

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 Tiliaamurensis Rupr., Pinuskoraiensis Sieb. & Zucc, Quercusmongolica Fisch. & Turcz., and Fraxinusmandshurica L., whereas that of ecosystem 2 was dominated primarily by Pinuskoraiensis and Quercusmongolica. 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. Acermono Maxim, is much less dominant than its North American counterpart, Acersaccharum 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 Pinuskoraiensis, a five-needled pine with wingless seeds, in the mixed hardwood forest is discussed.