Abstract:

Aims Our objective was to determine the distribution pattern and climate characteristics of Kobresia in China.
Methods Distribution information was collected from the literature and floras. Climate information was collected from China’s meteorological stations. ArcGIS software and cluster analysis methods in SPSS software were applied to analyze data.
Important findings Kobresia is mainly distributed on the Tibetan Plateau and in northern China. Fifteen species have wide distributions, and ten have disjunct distributions. The ranges of elevation, latitude and longitude of Kobresia’s distribution are 1400-5 000 m, 23-46° N and 81-112 °E, respectively. Mean values of climatic factors are Holdridge annual biotemperature of 4-19 ℃, annual mean air temperature of 0-20 ℃, annual mean maximum and minimum air temperatures of 7-28 and -6-16 ℃, respectively, extreme high and low air temperatures of 25-40 and -37-0 ℃, respectively, mean air temperature in January and July of -14-13 and 11-24 ℃, respec- tively, highest air temperature in January and July of -7-23 and 18-30 ℃, respectively, lowest air temperature in January and July of -22-7 and 5-20 ℃, respectively, mean air temperature in spring, summer, autumn and winter of -4-19, 9-23, 6-21 and -11-15 ℃, respectively, Kira warmth index and coldness index of 23-159 and -36-0 ℃, respectively, annual precipitation of 154-1500 mm, precipitation in spring, summer, autumn and winter of 19-135, 53-662, 48-545 and 5-92 mm, respectively, Holdridge annual potential evapotranspiration of 261-1100 mm, Thornthwaite annual potential evapotranspiration, aridity index and humidity index of 399-895 mm, 67-786 and 179-816, respectively, and sunshine duration from April to October of 990-2100 h. Generally, there is a high richness of Kobresia under lower or medium mean value of thermal factors, medium mean value of pre- cipitation, aridity or humidity or higher mean value of sunshine duration. As for extreme value of climatic factors, the range for minimum-maximum value of annual air temperature, the range for minimum value of extreme lowest and maximum value of extreme highest air temperature, air temperature range for minimum value in coldest and maximum value in hottest month, air temperature range for minimum value in winter and maximum value in summer are -6-21, -12-28, -48-42, -32-33 and -20-25 ℃, respectively, and the ranges for minimum-maximum values of annual precipitation, aridity index and sunshine duration from April to October are 15-1800 mm, 7-890 and 701-2 300 h, respectively. There is a high species richness of Kobresia under lower and medium extreme values of thermal factors, medium extreme value of precipitation, aridity, and higher extreme value of sunshine duration. The results suggest that Kobresia in China is primarily adapted to microthermal subhumid or mesothermal humid climatic types.

Key words: air temperature, climatic factor, geographical distribution, Kobresia