Abstract: By using the observation data of mean daily air temperature and relative humidity from 1951 to 2007, the daily body comfort index of 20 main tourist cities in China in the 57 years was calculated. Based on this calculation, the comfort grades and comfortable months of the cities were formulated. From north to south, the main tourist cities in China had a time distribution of comfortable months gradually changed from May-September to before May or after August/September, and the comfortable days showed an increasing trend. Along the Yangtze River, the comfortable months of main tourist cities were mainly April, May, and October, and the comfortable days were the most in the upper reaches, followed by in lower reaches, and middle reaches. From low to high altitudes, the time distribution of comfortable months tended to be in June and July, and the comfortable days showed a decreasing trend. Under the similar latitudinal conditions, the comfortable months and days were more in coastal tourist cities than in inland tourist cities. These results could provide scientific basis for the comprehensive exploitation of the advantages of China’s tourism climate resource, the reasonable arrangement of optimal travel time and places for tourists and travel agencies, and the development of tourism meteorological services for relevant departments.

Key words: Metribuzin, Puma, Alachlor, Chlorella vulgaris, Toxicity, Chlorophyll