Xianning City is located in the area between the middle plain of the Yangtze River and the hill in the south side of the Yangtze River, with a rolling landform and a complex climate, for which it is failure to use the conventional indexes to express its aridity index. In this paper, we introduce a concept of the mean dampness into the caculation of the aridity index,and suggest a concept of the ecological water-and-thermal paramter GMK, whick can be experessed as GMK=K/W (1) where K=0.16∑t/R is the arid degree,and W=2t/p the mean damp degree,s...
