Abstract: Mt. Wuyi, located at 27°37‛-27°54‛ N, 117°27‛-117°51‛ E, is the highest mountain in South-East China. Its main peak, Huanggangshan, is 2158 m above the sea level. In 1955, P. C. Chen organized the first expedition to Mt. Wuyi, and the authors investigated the different ravines and the forests of that area in 1976 and from 1979 to 1984 respectively. Up to now 355 species of the bryophytes have been found in Mt. Wuyi. I. The influence of the factors of geological history on the bryoflora of Mt. Wuyi Fujian Province, belonging to Cathaysian, one of three Chinese ancient lands, was a part of ocean until the end of the lower Tertiary. In the early Devonian, Fujian uplifted above the sea level, but it submerged in the sea later, and then uplifted above the sea level again in the upper Triassic. By the end of the lower Triassic the Himalayan movement influenced the paleogeography of China deeply, and the eastern and central mountains of Fujian uplifted again. In the Tertiary, Fujian was influenced by the hot maritime weather, so the tropical evergreen forests existed in southern Fujian at that time. The conclusion was made by Z. B. Zhao in 1983 after his long period of study on geological history of Fujian Province since the Yanshan movement. According to the morden geographical distribution of Chinese bryophytes, it seems that the above influence might be related to the bryophytes of Mt. Wuyi and also the southern part of Zhejian Province. By the end of the Tertiary the weather became cold in most parts of China. Since then the cold weather and hot weather alternated several times. One kind of the endemic elements of the bryoflora formed in the area from the south-eastern coast of China to the southeastern Xizang (Tibet), including Japan. They are not specialized at the family level or closely related to each other, but they have similar distribution and belong to different families. In the Quaternary, Mt. Wuyi gradually uplifted following the Himalayan movement. As the weather cooled down in the upper part of the mountain, deciduous broad-leaved and needleleaved trees increased there. Meanwhile, temperate genera and species of the bryophytes spread and invaded South China and entered Mr. Wuyi. Rhytidiadelphus and Hvlocomium probably began to grow in Mt. Wuyi at that time, and their distribution is quite different from their primary one. On the other hand, a part of tropical and subtropical bryophytes might enjoy the changed weather and environment in the Quaternary and existed in a few small localities of Mt. Wuyi, and the genera Haplomitrium, Endotrichella and Floribundaria are probably their representatives. From the point of view of geological history we are now living in the interglacial period and the present natural conditions will last continuously, so they will steadily influence the bryoflora of Mt. Wuyi in a long period of time. 2. Essential characteristics of the bryoflora in Mt. Wuyi Due to the geographical position and the other factors of Mt. Wuyi the bryoflora is represented by numerous tropical and subtropical elements (34.1%), but the East-Asiatic endemic ones (79.2%) are characteristic of the bryoflora in Mt. Wuyi (Tab. 1). The tropical and subtropical families of the bryophytes, found south of Changjiang (Yangtzi) River, are Haplomitriaceae (1 genus, 3 species), Porellaceae (2 genera, 8 species), Frullaniaceae (2 genera, 10 species), Lejeun eaceae (21 genera, 35 species), Trachypodaceae (3 genera, 4 species), Meteoriaceae (10 genera, 17 species), Neckeraceae (5 genera, 8 species) and Hookeriaceae (3 genera, 3 species). The above 8 families, including 46 genera and 85 species, represent about 1/4 genera (24.3%) and less than 1/4 species (23.9%) of the bryoflora of Mt. Wuyi. Most species of East-Asiatic elements show very close relationships with Japan, and are widely distributed from the low altitude of Mt. Wuyi to the summit of Mt. Huanggangshan. However, the Holarctic species (26.8%) are also important elements of the bryoflora in Mt. Wuyi, showing its transition nature, although it is located in the subtropics. Moreover, the in fluence of the Himalayas also exists in Mt. Wuyi, and the Himalayan elements cover 14.4% in the bryoflora of Mt. Wuyi. The similarity coefficients between the bryofloras of Central and South America, Africa and Oceania and that of Mt. Wuyi are from 5.0-9.2% respectively. The endemic species are not very many and cosmopolitan species are only 7 there. In 1958, P. C. Chen designated Mt. Wuyi as “the transition region of South and North China rich in East-Asiatic genera and species”. His very important conclusion is essentially in accordance with the fact of the bryoflora on Mt. Wuyi. Recently, some of the new records fur ther show the characteristics of the bryoflora in Wuyi. Two facts are worth being mentioned. One is that East-Asiatic genera are only five in Mt. Wuyi. However, there are 9 East-Asiatic genera in Mt. Huangshan more than in Mt. Wuyi; 4 East-Asiatic genera are recorded in Mt. Shennongjia. The other is that epiphyllous liverworts in Mt. Wuyi, consisting of 7 families, 21 genera and 36 species, are less than on Hainan Island and Xishuangbannan, located in the tro pics in China. 3. Comparison between the bryoflora of Mt. Wuyi and those of the neighbouring regions As China covers a very large area, bryofloristic elements are quite different in the diffe rent regions. In this section, we are concentrated on making a comparison between the bryof loras of Mt. Wuyi and the regions belonging to the Central China of the bryoflora named by P. C. Chen. Huaping Forest Region, Guangxi Zhuang Autonomous Region in South China, with both latitute and altitude very similar to Mt. Wuyi, is included in this comparison (Fig. 1). According to the rough estimation, the similarity coefficient of moss genera between Mt. Wuyi and Huaping is 56.3%, and those between the mountain and southern Zhejian and Mt. Huangshan, Anhui, are 62.7% and 51.6% respectively, while the similarity coefficient of the genera of the mossfloras between Mt. Shennongjia and Mt. Wuyi is 46.8%. Table 2 shows the statistics of mosses in Mt. Wuyi and the others, but the bryoflora of Huaping needs further study However, it is very interesting to note that Haplomitrium and Pleurozia of liverworts are both found in Mt. Wuyi and Huaping Forest Region, and the similarity coefficient between the mossfloras of Mt. Wuyi and Zhejian Province is also higher than those mentioned above. Tropical and subtropical elements reduce towards the north in China, and temperate ones increase. Huaping is located in the south, and, as expected, some tropical and subtropical genera such as Hookeriopsis and Symphyodon have been found there, but not in Mt. Wuyi; several temperate genera, such as Schwetschkeopsis and Fauriella, have been recorded in Mt. Huangshan, but not in Mt. Wuyi. For some unknown reasons, Octoblepharum and Neckeropsis are only found in southern Zhejiang, but not in Mt. Wuyi. Mt. Shennongjia, with its main peak over 1000 m higher than that of Mt. Wuyi, is located in its northwest, and more than ten temperate genera, such as, Ceratodon, Aulacomnium Myurella, Bryonoguchia and Abietinella have been found there. Generally, Mt. Wuyi belongs to the central subtropical region of China, and East-Asiatic endemic genera are the main elements of its bryoflora, but the bryoflora also consists of tropical and subtropical elements with some temperate ones. 4. East-Asiatic endemic genera in the bryoflora of Mt. Wuyi In the bryoflora of Mt. Wuyi, one of the main elements, East-Asiatic endemic genera, should not be neglected (Tab. 4). East-Asiatic endemic genera in Mt. Wuyi (five) are less than in Mt. Huangshan and Mt. West Tianmu, although the positions of the latter two are very close to Mt. Wuyi. East-Asiatic endemic genera of liverworts are Trichocolea and Macvicaria so far found in Mt. Wuyi, and the mosses are Myuriopsis, Meteoriella, Pseudospiridentopsis (Fig. 1). Myuriopsis is only distributed in Taiwan Province and Mt. Wuyi, and the other four are distributed in Mt. Huangshan or Mt. West Tianmu, and also in Taiwan, besides in Mt. Wuyi. About thirty EastAsiatic endemic genera have so far been known in China, which means that about one sixth of East- Asiatic endemic genera of the bryophytes occur in Mt. Wuyi. We may notice that nine and seven East-Asiatic endemic genera of the bryophytes have been recorded in Mt. Huangshan and Mt. West Tianmu respectively. In Mt. Shennongjia, Central China, there are four East Asiatic endemic genera, but only two have been found in the Huaping Forest Region, South China. In Mt. Dinghua, located south of Mt. Wuyi, on East-Asiatic endemic genus of the bryophytes has so far been found. East-Asiatic endemic genera of the bryophytes are mainly limited to China, Korea and Japan, including the East Himalayas, rarely occur in South Asia, Siberia of the Soviet Union. Therefore, these genera enjoy a warm and moist environment. In Mt. Wuyi, all the East-Asiatic endemic genera are monotypic ones with a disjunct distribution. Now in Taiwan Province five of six recorded East-Asiatic endemic genera are common to Mt. Wuyi. In Japan, about eleven, i.e. one third of, East Asiatic endemic genera so far found are common to China, which shows a long history of the phytogeographical relationships between Japan and China. East Asiatic endemic genera of the bryophytes might therefore exist on islands of Taiwan Province and Japan before they were separated from the mainland of Asia. However the fossil evidence is still lacking in the bryophytes, so we are not able to discuss about the distribution area and the distribution center of the East-Asiatic bryoflora in detail. The above estimation is more or less related to geological history, and we assume that the East-Asiatic endemic genera have existed at least since the end of the Tertiary. Starting from the Quaternary, the climatic change during glacial epoch has been possibly the most important factor affecting the bryoflora in Asia, and the upheaval of the Himalayas has stimulated the diversity and the specialization of the bryophy tes. Considering these factors, East-Asiatic endemic genera might be the “Tertiary fossil plants”. Another problem is difficult to explain, because Mts. Huangshan, West Tianmu and Shen nongjia were once influenced by glaciation directly, although Chinese geologists hold different views. However, no evidence of glaciation has been found in Mt. Wuyi. It is worth to study the close relationships between Mt. Wuyi, Mt. Huangshan and Mt. West Tianmu, where is the distri bution center of the East-Asiatic endemic genera. The above three mountain regions share half of the East-Asiatic endemic genera, and about 32% genera of the others are found in two of them (Fig. 2). Myuriopsis, one of the East Asiatic types, was only recorded in Taiwan Pro vince, Japan and Korea. Neodolichomitra, occuring in Taiwan Province, is endemic to China. More or less the differentiation has taken place in Mt. Huangshan, Mt. West Tianmu and Mt. Wuyi. The number of the East-Asiatic endemic genera is smaller in Mt. Wuyi, so it is possibly located on the border of the distributional center of the East-Asiatic endemic genera. Moreo ver, three of four East-Asiatic endemic genera in Mt. Shennongjia are also found in Mt. Huang shan and Mt. West Tianmu, but the other East-Asiatic genus in Mt. Wuyi is common to the mountain areas in SW China, the Qinglin Range of NW China, and the isolated mountain areas of NE China. Considering all the characteristics of the bryoflora of Mt. Shennongjia, we assume that Mt. Shennongjia may belong to another distribution center, including SW part of Sichuan Province, and the other neighbouring mountains.

Key words: bryoflora, East-Asiatic endemic genera, distribution center, Mt.Wuyi, SE China