绿洲地理特征及其气候效应

THE GEOGRAPHICAL FEATURES AND CLIMATIC EFFECTS OF OASIS

根据绿洲的一些共性给出了绿洲的科学定义。并且根据以往大量研究成果 ,系统地归纳了世界上绿洲分布的区域类型、形成的客观条件、需要的水文环境、植被和土壤类型及其分类等地理特征 ,全面总结了绿洲“冷岛”结构、“冷岛”效应、“湿岛”结构、临近荒漠逆湿、高额可利用能量、风屏作用、动力和热力效应、增雨作用等主要气候效应。在此基础上 ,提出了绿洲具有系统性、对水的依赖性、高比照性、尺度性、高效性、脆弱性、演化性等本质特性。

According to the common natures of oases in the world, scientific conception of oasis is given out. Based on a lot of the previous research results, the distribution regions of oasis, the objective conditions forming oasis, the hydrological environment of oasis, oasis vegetation types, oasis soil types and other geographical features of oasis are induced systematically. In the same time, the cold island structure of oasis, the cold island effect of oasis, the humid island structure of oasis, the humidity inverse of atmospheric surface layer over desert near oasis, surface high utilizable energy (or net radiation), wind barrier effect, dynamic effects, thermodynamic effects, effect of enhancing rain and other climatic effects are summarized comprehensively. And from the geographic features and climatic effects of oases in the world, the essential properties, such as systematization, dependence on water, high contrast, proper scale extent, high efficiency, frailty and gradual evolution, which is of all oases, are pointed out. Finally, the effects of human action on oasis are discussed, and the problems and suggestions on oasis research are inquired into.