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Observations on the Flora and Vegetation of Taibai Shan, Qinling Mountain Range, Southern Shaanxi, China
Ying Tsun-Shen, Li Yun-Feng, Guo Qin-Feng, Cui He
Acta Phytotaxonomica Sinica. 1990, 28 (4 ):
261-293.
Taibai Shan Mountain is generally known as “The highest mountain in the Qinling Mountain Range.” It is situated between 33°40' and 34°10'N latitude and 107°19' and 107°58'E longitude in southern Shaanxi Province. The area is deeply cut on all sides by four, V-shaped valleys, which gives the landscape a steep topography. The highest peak is about 3767 m above sea level, and the relative elevation of the whole Taibai Mountain area ranges from 1000 to 2200 m. Five chief soil types have been described in this region and are vertically distributed as follows: 1) Ochric castanozom, below 1000 m; 2) Brown forest soil, 1000-1500 m; 3) Podzolic brown earth, 1500-2800 m; 4) Podzolic soil, 2800-3000 m; 5) Alpine meadow soil, above 3000 m. Fu (1982) in an analysis of the Taibai Shan mountain area's summer climate, and in comparing temperatures on the north and south sides, described higher maximum tempera- tures at low elevations on the south, but lower temperatures at high elevations on the north. Rainfall is much higher on the south. The rugged topography of the Taibai Shan Range still preserves some tracts of natural er semi-natural vegetation at higher elevations. Our vegetational survey was confined to localities above 1300 m, whereas collecting specimens for documenting the flora extended over the whole area from the foothills ro the peak. On the basic of these floristic, vegetational and environmental studies in the Taibai Shan Mountain we are now able to draw some conclusions on the nature and relationships of the interesting flora and vegetation, and to discuss to some extent the phytogeography of an im- portant segment of the Chinese flora. 1. Survey of large families of angiosperms. There are twenty large families of flowering plants in the Taibai Shan Mountain of Qinling Range (Table 1). The largest families are the Asteraceae (175 species), Poaceae (123 species) and Rosaceae (124 species). The Rosaceae is a major family in this region, and species in the family are characteristic members of the flora and vegetation of the temperate zone in China. Both Asteraceae and Poaceae are also frequently found in forests and else- where in this region. There are three families with 60 to 90 species; three families with 50- 60 species; three families with 40-50 species and eight families with 20-40 species. These families combined contain 1186 species, including 655 endemic to China, making up 66.6% of the total flora, and play an important role in shaping the characteristics of the forests of the Taibai Shan Mountain. All these large families are temperate in nature. 2. Relationships of the Taibai Shan flora with others The Taibai Shan Mountain of the Qinling Range is very rich in genera (657) and spe- cies (1782) of flowering plants. Based on their geographical distribution, the genera of flowering plants in the Taibai Shan Mountain are classified into 15 distribution types (Table 2). In accordance with our analysis of all of the distribution types it is reasonable to con- clude that: among the native genera in the flora of Taibai Shan,130 containing 242 species (22.1%) are tropical, 436 containing 1186 species (73.8%) are temperate and 24 (4.1%) are endemic to China. From these figures the flora of Taibai Shan can be thought of as com- posed of temperate elements. To determine the floristic affinities of the area with others within China, nine mountain regions were selected for a comparison (Table 5). Based on the worldwide distribution of genera in the ten mountain regions, 15 distribution patterns can be recognized (Table 4). A comparison of the similarities among the ten mountainous regions in China, based on the distribution of genera, shows that the floristic affinities of the Taibai Shan are first with the Daqing Shan in northern China and the Shennongjia region in central China, and secondly with the Jinfo shan, the Fanjing Shan, the Yulongxue Shah and the Nanjiabawa Mountain in southwestern China. 3. The structure and vertical distribution of communities in the Taibai Shan Mountain. The diagrammatic structures of the chief plant communities in the Taibai Shan Moun- tain are given in Fig. 8.1-8.6. All of the dominant species, except Betula utilis, are endemic to China. The distributional areas of some of dominant species overlap in the Qinling Moun- tain Range (Fig. 2 and 3). On the basis of floristic composition and the coefficients of similarity between narrow belts of vegetation (Tables 7 and 8), the vertical distributions of the plant communities on different slopes are shown as follows: Northern slope: 1) Quercus aliena var. acutiserrata forests (below 1800 m); 2) Quercus liaotungensis forests (1800-2200 m); 3) Betula albo-sinensis forests (2200-2800 m); 4) Abies fargesii forests (2800-3000 m); 5) L.arix chinensis forests (3000-3400 m); and 6) subalpine scrub (above 3400 m). Southern slope: 1) Quercus variabilis forests (below 1500m); 2) Ouercus aliena var. acu- tiserrata forests (1500-2000 m); 3) Betula utilis forests (2000-2500 m); 4) Abies fargesii forests (2500-3000 m); 5) Larix chinensis forests (3000-3400 m); and 6). subalpine scrub (above 3400 m). 4. Species diversity along gradients of elevation. In terrestrial habitats, variation in species diversity along gradients of elevation and avai- lable soil moisture are, generally speaking, almost as striking as latitudinal variation. Varia- tion in the diversity of species of trees, shrubs and herbs with changes in elevation in the Taibai Shan Mountain of the Qinling Range is discussed. The number of tree species declines with increasing elevation, but the diversity of shrubs, and especially the herbaceous species, reaches the greatest richness at intermediate elevations in the Taibai Shan Mountain (Fig. 9). Whittaker (1960, 1977) has reported a similar pattern on temperate mountains in the United States. 5. Analysis of life-form spectra. A comparison of life-form spectra in the vegetation between the southern and northern slopes shows that the five principal classes of life-forms on the southern slope (Fig. 8. b) are very similar to those on the northern slope (Fig. 8. c). The correlation of life-form spectrum with altitude (Table 9) reveals a significant trend; a steady decrease of phanerophytes, but conversely increase of therophytes with altitude. In Table 10 is a series of spectra for certain community types in different regions. Here we see that the temperate deciduous broad-leaved forests of the Taibai Shan Mountains, Changbai Shan mountains, Beijing area in northern China and in the Appalachian region in eastern North America have very similar life-form spectra. In another case the evergreen broad-leaved forests of the Jinyuy Shan and Wuyanling mountains in southeastern China have strikingly similar life-form spectra.
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