基于北京 546 年的旱涝资料, 通过 Mann2Kendall 检验、滑动 t 检验等方法, 分析得到不同旱涝变化趋势, 并使 用马尔可夫链研究了整体和每个趋势各状态间的转移概率以及重现期。研究表明北京地区旱涝灾害具有明显的趋 势性, 整体呈现/ 涝- 旱- 涝- 旱0 波动, 局部有旱涝急转的现象。1470- 1579 年整体偏涝, 转向偏涝年份的概率最 高( 311 3% ) ; 1580- 1768 年整体偏旱, 转向正常年份的概率最高( 341 3% ) , 且容易发生多年连旱; 1769- 1898 年整 体偏涝, 转向正常年份的概率最高( 411 5% ) , 且旱涝灾害发生概率基本相同; 1899- 1961 年由涝转旱, 转向偏旱年 份的概率最高( 351 1% ) ; 1962- 2015 年整体偏旱, 转向偏旱概率最高( 291 7% ) , 且容易发生多年连旱。对 546 年旱 涝整体分析, 旱涝转移趋向于正常, 但整体处于一个偏旱的状态。

Based on the data of dro ug hts and flo ods o ver the last 546 y ea rs in Beijing, we o btained different trends o f flo ods and dr oughts using Mann2Kendall test and mo ving t2test, and w e used Mar ko v chain to study the t ransfer pr obabilit y and recurrence of different states in each tr end. T he st udy show ed that the dro ug ht and flo od disasters in Beijing manifested o bv ious tenden2 cies. The over all trend was " f loo d2dro ug ht2flo od2dr ought " fluctuatio n, w ith rapid shifts betw een dro ug ht and floo d at some times. During 147021579, Beijing was pr one to f loo d and had the highest pro bability of t ransferring to a part ial floo d year ( 311 3% ) . During 158021768, Beijing w as pro ne to dr ought and had the highest probability o f transferring to a no rmal year ( 341 3% ) ; it w as also v ery likely to hav e co ntinuous dr oughts. During 176921898, Beijing w as pr one to floo d and had the hig hest pr obability o f t ransferring a normal year ( 411 5% ) ; t he occurrence pro babilities of droug ht and flo od disasters wer e basically the same. During 189921961, Beijing t ransf erred fr om flo od to droug ht and had the highest pr obability of transferring to a partial dr ought y ear ( 351 1% ) . During 196222015, Beijing w as pro ne to droug ht , and had the hig hest probability of tr ansferring to a partial dr ought y ea r ( 291 7% ) ; it w as also v ery likely to have continuo us dr oughts. The ov erall ana lysis of 546 years o f dro ug hts # 2 and flo ods show ed that the tr ansfer o f dr oughts and floo ds tended to be no rmal, but the o verall situation was partial dro ug ht.

国家重点研发计划项目( 2016YFC0401407); 国家自然科学基金项目( 51379216) ; 中国水科院创新团队项目( WR0145B622017) Funds: Nati on al Key R & D Program (2016YFC0401407) ; Nati on al Natural S cience Foundation of Chin a ( 51379216) ; Basic Res earch Fund Project of Ch ina IWH R ( WR0145B622017)