The Study Of Gramineae In Karakorum Mountains Of China

Karakorum Mountain located in the southwest of Kunlun Mountains. The mountain region extended from the southeast of Pamir Plateau to the northwest of Qiangtang Plateua. It's about 1100km long and 100-220km wide. The east of the mountain region located in Afghanistan, the southen is Pakistan and India, the northen and the easten located in China. The Chinese Karakorum Mountains include the area of two sides of Karakikuer River in the southwest and the area of southen Yarkant River in the county of Taxkorgan, the south area of 219 national highway in county of Yecheng, Pishan and Hotan, and the northwest of the countyof Rutog, loacated in the Ali District of Tibet. We made the taxonomy resaerch of plants of Graminene in depth, on it's basis, species diversity was sistematically anysised and the resources of Gramineae in this region were evaluated. At last, we give some advice on how to utilize them in reason.The result indicated that there are 18 genera,79 species,4 subspecies,2 variaties of wild Gramineae which is the second biggest Family in Chinese Karakorum Mountains, respectively accounting for 7.9% and 5.7% of genera and species of China.13 species were new recorded in Chinese Karakorum Mountains, and 1 species in Xijiang,5 species in Tibet. Though the species is few, they have the strong characteristic of cold,arid,lean,radiant endurance. They are also the establisher or dominance of plant community in Karakorum Mountains with high altitude,lean soil and the poorest environment. There are 7 multigenera distributed in this region, which takes 38.9% of all genera,67 species takes as much as 78.8% of all species. There are 6 oligotypic generas,6 species occupied 33.3% and 7.1% of total genera and species; 5 monotypic genera,12 species, occupied 27.8% and 14.4% of total genera and species.There are 8 Chinese endemic species,7 Xinjiang endemic species and in this area. There are only 1 species and 1 subspecies of Karakorum endemic species and 8 Xinjiang endemic species were distributed in this region without Tibet endemic species and species distributed only in Tibet. The endemic phenomenon is not obvious. The reason is that about 3 quarters of the region located in Xinjiang province and only 1 quarter in Tibet, also indicated that the relationship of Gramineae in this region and adjoining area is intimity.There are 76 species of Gramineae in this region are perennial plants,3 species of Eremopoa and Bromus are annual. They acclimatized themself chronically to the poor envirmonent.The distributive types of genera of Gramineae in Chinese Karakorum Mountains is simple. North temperate which cantains 12 generas has a percentage of 2/3 plays an absolutely role in this region. Most of them are the establisher and dominance of the meadow and grassland in difference apeak belt in this region. Cosmopolitan,pantropic and the old world elements also exist in this region. It shows that the phenomena of geography isolation is not obvious, infiltration is pervasive in north temperate and other distributive types. The genera similarity of Gramineae between Chinese Karakorum Mountains and Pamir Plateua is higher (about 88.9%),83.3% with Kunlun Mountains is less. The reason is that the entironment of Chinese Karakorum Mountains is similar to the Chinese Pamir Plateua and Kunlun Mountains. The genera of unification distribution is obvious. The species similarity of Gramineae between Chinese Karakorum Mountains and Pamir Plateua is higher (about 43.5%),30.1% with Kunlun Mountains is less. The substitute in species is higher in this region, the differentiation is clear in different apeak belt.97.7% of Gramineae are good resource of forage grasses, they are the most important food of domestic and wild animals; 22 species of Leymus and Elymus are the kindred of crops; 14 species of Achnatherum,Phragmites,Calamagrostis,Leymus are the plant resource of windbreak and sand fixation; 26 species of Poa and Puccinellia are the resource of plant in keeping from water and soil erosion; 9 species of Poa,Festuca,Koeleria are the grass of cold season lawn in high altitude area and northen area.