摘要
选择湖南省14个地级市(州)1995—2009年4—9月降水量、降水量的距平百分率、最高水位值以及对应年份的年末耕地面积、农作物受灾面积、受灾人口、人口密度、产值密度8类指标作为自变量,损失率为因变量,构建指标体系,利用分类与回归树模型逐级提取出了造成洪涝灾害损失的主要因子,依次为农作物受灾面积、受灾人口、7月降水量、6月降水距平百分率、9月降水量以及人口密度。同时确定了影响阈值,当农作物受灾面积不超过56.8×103hm2,且受灾人口少于158.2万人时,预测损失级别为1,属于微灾;而农作物受灾面积超过81.1×103hm2,7月降水量少于343 mm,6月降水距平百分率大于94.5%时,预测损失级别为5,属极重灾。CART模型应用简单、结果客观,为洪涝灾害损失评估及预测开辟了一条新途径。
Based on collecting, reorganizing and analyzing the history data about Shanxi in Ming Dynasty, this paper studied the grade series, stage changes, different grades＇ periodicity and reason of the frost-snow and low-temperature disasters in Shanxi. The statistical results showed that the disasters had 114 times, the disasters＇ grade may be divided into mild, moderate and severe disaster, and they were respectively 22, 66 and 26 times. The disasters can be divided into two stages. The first stage was from 1368 to 1519, the second stage was from 1520 to 1644. The first stage was that the disasters happen occasionally, and most of them were mild and moderate disas- ters. The second stage was that the disasters happen frequently, and most of them were moderate and the most seri- ous. According to wavelets analysis, it was known that there were mainly 2 -3a period, 9 - 14a period and 45 55a period. There were four cold climate events from 1531 to 1533, from 1578 to 1588, from 1591 to 1607 and from 1631 to 1642. The cold weather events had occurred after 1520 and prescribed the climate of the middle and late Ming Dynasty was colder than that of the early Ming Dynasty.
出处
《地域研究与开发》
CSSCI
北大核心
2012年第6期106-110,164,共6页
Areal Research and Development
基金
高等学校博士学科点专项科研基金项目(20100003110019)
国家重大科学研究计划项目(2012CB955402)
国际合作项目(2010DFB20880)
关键词
洪涝灾害
CART模型
损失评估
预测
湖南省
frost-snow and low-temperature disasters
characteristics
periodicity
cold climate events
Ming Dynasty
Shanxi Province
