| Based on the extensive field specimen collection and ecological quadrat investigation, research on the bryoflora and ecology of bryophytes in the headwaters region of Urumqi River were carried out for the first time. The main results are as follows:1. Studies on species diversity of bryophytes in the headwaters region of Urumqi RiverBased on the investigation and more than 540 specimen identification of bryophytes from the headwaters region of Urumqi River, 148 species in 70 genera and32 families of bryophytes are reported here. Of these, one species belonging to one genera and one family is hornworts; 17 species belonging to 12 genera and 10 families are liverworts; 130 species belonging to 57 genera and 21 families are mosses. Bryum stirtonii and Jungermannia japonica are new to China. Four species are new to Xinjiang province. The characteristics of dominant families and genera in the headwaters region of Urumqi River were also discussed.53 species of bryophytes were repoted in the ecological quadrat investigation. The species similarity between alpine forest and alpine sparse grass scrub belt was the highest(0.583), while the species diversity index of alpine sparse grass scrub belt was the highest, but the number of bryophytes in alpine forest is the richest(27 species).The bryo-diversity in the headwaters region of Urumqi River is rich and its bryoflora could be divided into nine geographical elements. Of those, North Temperate, East Asian, and Endemic to China elements account for 69.84%, 8.73%and 6.35%, respectively.2. Ecological study on bryophytes in the headwaters region of Urumqi RiverThe community types in the headwaters region of Urumqi River could be divided into four types, including hydrophytia, petrophytia, geophytia, and epixylophytia.The geophytia is the most widely distributed, and could be divided into more sub-types further.All the mosses in the foreland of the reatreating Tianshan No.1 Glacier arearcocarpous mosses, without any pleurocarpous mosses. The results supported the hypothesis that arcocarpous mosses are more adapted to harsh environments than pleurocarpous mosses. Otherwile, the way of sexual reproduction is employed by most mosses instead of asexual reproduction. The reason may be the richness of water dissolved by the glacier. The breed system of mosses in glacier foreland are mainly dioecious(69.23%), much more than those of monoecious(26.92%) and polyoicious(3.85%) indicating the way of unisexual reproductive may be more advantages in extreme climate.The bryophytes frequency and coverage on the ground in 50 sites in the headwaters region of Urumqi River were investigated and sampled. TWINSPAN and Detrended Correspondence Analysis(DCA) was used to analyze their distribution patterns. These results are essentially similar, with the community type in the headwaters region of Urumqi River can be divided into four types.Canonical Correspondence Analysis(CCA) was also applied to study the relationships between the 50 saxicolous plots(or 53 species of bryophytes) and the environmental factors. The results showed that the influence of herb coverage, altitude,soil humidity, and tree canopyare the most important factors in distribution pattern of bryophytes.It is the first time for studying the bryophytes of alpine region and will help broaden the research area of the bryophytes, providing theoretical basis for the procetion of environment and bryophytes. At the same time, these results proves the strong adaptability to extreme environment and extensive distribution of the bryophytes. |
