【摘要】 <正> 一、干热河谷的气候特点 云南的干热河谷气候,受大气环流尤其是地形因素的影响较大。就环流因子而言,各流域所受影响大体相似,从而形成相似的气候特点:干湿季非常分明,干季湿度小、云量少、晴天多、日间气温高、昼夜温差大;湿季水汽多、云量多、阴天多、日间气温不高、昼夜温更多还原

【Abstract】 The dry-hot valley in Yunnan refer to both mountainous-hilly land and wide flat areas along Jinsha, Lancang and Nujiang valleys, distributed between 23°01’ ~27°20’ of north latitude, and 85°45’~103°20’ of east longitude, with elevation under 1 600 meters. In such areas, specific climate types and vegetation forms are established under the influence of both planetary circulation and topography, and there exist plants for some particular purposes, among which are plants for lac host and fibres, wild fruit trees and grass crops. Some of them, such as Phyllanthus emblica, Cajanus cajan, Zizyphus mauritiana are to be further exploited for their value of use. If used properly and reasonably, these plants can be renewed naturally and cultured for their capacity of regeneration, or otherwise, the results will be the exhaustion of plant resources and further soil erosion.更多还原