The lichen genus Pertusaria from Bailong River valley of Gansu, China
甘肃白龙江流域鸡皮衣属地衣的研究

1 INTRODUCTION Bailong River,a tributary of Jialing River belonging to the Yangtse River system,is located in the southern part of Gansu Province and the northeast rimland of Qinghai-Tibet Plateau,with total length of over 600kin and drainage area of about 31,800km2.Originating from Dagcanglhamo,Luqu of Gansu Province,the river flows through Min Shan Mountains from northwest to southeast,and passes through Tewo,Zhugqu,Wudu and Wenxian.The annual temperature of the river valley is around 4.7-12.7℃,and annual precipitation is 448.9-911.6mm.The climate of the upper reaches is temperate-humid,of the middle reaches warm-humid,and the lower reaches subtropic-humid.