脆弱带坝上后山地区沙漠化因子波动的空间类型与耦合

Fluctuating spatial types and coupling of desertification factors of Ectone in the area of upland and rear hill

利用经验正交函数（ＥＯＦ）法，确定了生态脆弱带内蒙乌盟后山河北坝上地区年降水、气候产量、牲畜增减变化、气候风蚀力和年大风日数等５类沙漠化因子波动的空间类型．各因子典型场在空间格局、变化方向上极为相似，只是年大风日数相对特别一些．通过分型归纳，将波动的空间类型化为３型６类．Ａ型为全区域变化同步，Ｂ型代表河北坝上与内蒙变化反向，Ｃ型反映中部的内蒙农牧交错带同北部的乌盟、锡盟草原以及东南部的河北坝上变化反向．围绕与沙漠化的关系，可将各因子１９６０—１９８０年逐年的空间耦合类型分为协调型、脆弱型和中间型３种．依据波动的空间类型，可建立地区粮食、牲畜在极端灾害年区域间的协调救助模式。

Making use of empiric orthogonal function, the paper determined fluctuating spatial types of desertification factors such as precipitation, climatic output of grain, relative change of livestock, climatic wind erosive force and days of yearly gale in the area inclucling real hill Wu League, Inner Mongolia and upland in Hebei Province. The spatial types of these factors resemble much in structure and change direction except that of days of yearly gale and they can be induced into three types and six sub-types. Type A means the total area change in-phase, type B is that upland of Hebei Province and Inner Mongolia change in just opposite direction, type C is the pat- tern that the agro-pastoral zone of Inner Mongolia in middle reverses the pastoral zone in the north and upland in the south. According to the relation with desertification, the spatial coupling of five factors during 1960-1980 can be divided as three status of harmony, weakness and medium. Based on the fluctuating spatial types, a concerted model of disaster prevention and reduction among the regions for the extreme year of grain and cattle can be established.