摘要
讨论了区域洪涝指标，提出了流域性洪涝的概念及其指标计算方法。在《中国近五百年旱涝分布图集》的基础上，将我国分成１０个流域，建立了各流域近５００年流域性洪涝指标序列及其等级划分标准，初步分析了我国流域性洪涝的基本特征。我国流域性洪涝具有较高的发生频次，北方区域内的各流域具有相对一致性，而南方则具有相对独立性。我国流域性洪涝在南方或北方区域内均具有一定的相关性，全区域则呈现“南涝北不涝、北涝南不涝”的南北分异特征。我国流域性洪涝具有不同长度的周期性，以淮河流域为例，流域性洪涝存在大约４６０年、２００年、８０年和４０年的周期变化及一些更小尺度的波动。
Floods are a kind of frequent natural disasters. Regional floods which are widely ranged are more serious from an economic viewpoint. It can tremendously influnce the economics of an area, or even a country. Therefore, studying regional floods not only is an organic part of disaster reduction reseach, but also has an important significance of river basin planning in flood control, rational utilization of land and sustainable development of local economics. Many researches have been made about the regoinal flood index according to the abundant historical data in china. These researches consider the area, which is a basic factor of regional floods, less, and can′t pratically give expression to the contribution of different flood area and different flood grade to regional floods. Therefore, the regional floods which the area of a certain grade in a certain river basin and year is exceeded to a certain proportion of the totol area are defined as basin wide floods (BWF) in this paper. The index of BWF is also suggested. On the basis of the “yearly atlas dryness/wetness in China for last 500 year perid”, 10 river basins are divided in the eastern part of china. A series of BWF indexes of each river basin for last 500 year period (1470～1991) are established. The criteria of BWF grades are proposed. Some basic characteristics of BWF in China are analysed in this paper. The analysis shows that: ①The frequencies of BWF in China are relatively high. The BWF of various river basins in the Northern region is comparatively interrelated, and in the southern region, is relatively independent. ② It is correlative to some extent for the simultaneous occurrence of BWF in river basins either of the Northern region or of the Southern region. The correlation of river basins in the Northern region is higher than that in the southern region. The simultaneous ocourrence of BWF statewide has the North South different feature which is occurred “either in the Northern part of china, or in the Southern part”. ③ The frequencies of BWF for successive years in the eastern part of china are relatively higher. ④ The BWF in China has periods with different time span. The BWF in the Huaihe river basin, for example, has the periods about 460 year, 200 year, 80 year and 40 year and some other shorter time span oscillations.
出处
《南京大学学报（自然科学版）》
CSCD
1996年第2期309-315,共7页
Journal of Nanjing University（Natural Science）
