摘要:
通过对历史文献资料的整理和统计分析,对明代1368-1644年的277年间洛河流域的洪涝灾害进行了研究。研究得出,洛河流域在这一时段内共发生了56次洪涝灾害,平均约4.95年出现1次;其中特大涝灾3次,大涝灾12次,中度涝灾16次,轻度涝灾25次。洛河流域明代洪涝灾害可分为4个大的阶段,其中1368-1429年和1490-1539年两个阶段是洪涝灾害少发阶段,1430-1489年和1540-1644年两个阶段是洪涝灾害多发阶段。洪涝灾害的自相似特征揭示了灾害的分形性质。研究发现,明代洛河流域的各级洪涝灾害的分维值都低于0.2,且无标度区相同,这表明了此时段洪涝灾害的长周期分量较强,且存在灾害的集中性。
关键词:
-
洪涝灾害
/
-
洪灾等级
/
-
分形
/
-
明代
/
-
洛河流域
Abstract:
Based on data of historical documents, the authors have studied flood disasters in Luohe River basin between 1368 and 1644 AD. It is found that the sequence has some features. There were 56 flood disasters in Luohe River basin between 1368 and 1644 AD, approximately occurring once every 4.95 years on average. The 56 flood disasters could be classified into 4 grades, catastrophic flood, big flood, moderate flood, and low flood, and of the floods, there were three catastrophic floods, 12 big, 16 moderate and 25 low ones. The circumstance could be divided into four main periods. The first period was between 1369 and 1429 AD, with a relatively lower frequency of floods. The second period was between 1430 and 1489 AD, with a relatively higher frequency of floods. The third period was between 1490 and 1539 AD, with a relatively lower frequency of floods. The fourth period was between 1540 and 1644 AD, with a relatively higher frequency of floods. The self-similar properties of flood disasters reveal the sequence's fractal feature. It is found that the fractal dimensions of flood in different grades are all below 0.2, with the same non-scaling range between 2 and 256, which demonstrates the sequence's bias of long period and the concentration of all grades of disasters.
下载: