| 1. | The dry / wet changes of surrounding area of bohai sea during past 500 years are divided into 7 stages , based on dry / wet indexes ( d / w ) of this area from 1470 to 1985 then , the changes of dry / wet spatial types ( d / wst ) and its related dry / wet regional different iation ( d / wrd ) features among different stages are analyzed . the results show that there are 4 main kinds of d / wst in this area , whose notability and spatial distribution features in different stages are apparently different , which reflects , very well , the changing process of the d / wrd of this region in past500 years . further analysis also presents that , in warmer period , the d / wst and the d / wrd patterns are relatively unsteady , meanwhile , the dry / wet changing difference among different parts of the region is relatively great , but , in colder period , it is just on the contrary . however , in the most severely cold period of the little ice age , t he area ' s d / wst and the d / wrd pattern sareveryu nsteady , and its d / wrd extenti salsot he high estin the whole past 500 years
用研究区1470 1985年的旱涝等级资料,划分了该地区500年来旱涝变化的7个阶段,讨论了不同阶段间旱涝型的变化及其旱涝区域分异意义,结果表明, 500年来研究区有4类主要旱涝型,各型旱涝在不同阶段的重要程度及场型特征均有较大差异,深刻反映了该地区500年来旱涝区域分异特征的变化,通过对500年来旱涝变化与温度变化的对比发现,较温暖期,研究区的旱涝型及旱涝区域分异格局较多变,旱涝变化的区域差异性较大,较寒冷期,旱涝型及区域分异格局较稳定,旱涝变化的区域差异性较小,而在小冰期最寒冷阶段,旱涝型及旱涝区域分异格局的变动十分频繁,旱涝变化的区域差异性亦最大 |
