我国地形小气候研究概况与展望

我国山地和丘陵的面积约占土地总面积的70%.因此,研究地形小气候对于了解山区气候资源,合理开发山区经济,发展农业生产具有重要意义.地形小气候与山地气候不同,前者是指相对高差在几米到几百米,水平距离在10米到10公里范围内的小的起伏地形对气候的影响,其特征主要表现在个别气象要素的数值和个别的天气现象上,且局限在近地面的空气层中.

ADVANCE IN THE INVESTIGATION OF THE TOPOGRAPHICAL MICROCLIMATE IN CHINA (SUM UP)

Mountainous and hilly regions cover a vast area of China. The mountainous topography is complex and various. Much differences in their landforms, altitudes, direction and slope resulted in much differences in the topographic microclimate, which would control the distribution of vegetations and soils, and thus it is not suitable to grow temperature demanded crops (such as citrus and, tea plants) in the unfavourable microclimatic conditions at the north and the middle subtropical areas in China, This paper summarizes the investigation on the survey of the topographic microclimate in China since mid-1950's. The primary content is as follows.(1) The influence of slope orientation (direction and slope) on the microclimate. The main character of the microclimate in the mountainous and hilly region in the changes of sunshine, radiant flux, temperature, precipitation and other meteorological elements with the slope orientation,(2) The influence of undulating country (top of a mountain, mountain slope, mountain valley) on the microclimate,(3) The influence of surrounding topography in a small scale region on the microclimate. Four types of the surrounding topography are studied according to their influences on minimum temperature and wind speed for both ra-diational and advectional weathers,(4) The influence of composition among hills on the microclimate,(5) A study of the topography inversion. Some regularities of the vertical distributions of the meteorological elements in the major mountainous and hilly region in China were found out,(6) The influence of special topography (such as a horseshoe shape topography) on the microclimate.As a result, we must select different species of crops and plants to suit the various microclimate conditions respectively, and to develop the diversified agriculture and forest in the mountainous and hilly regions in China.