利用1961 年- 2010 年贵州省81 个气象站的逐日降水量资料, 采用线性倾向估计、Mann2Kendall 检验和GIS 空间分析, 探讨了贵州省不同强度降水日数的时空演变规律和突变特征, 结果表明: 近50 年, 不同强度降水日数呈 先增加后减小的态势, 总降水日数表现为明显下降趋势, 下降速率为1. 93 d/ ( 10a) , 其中小雨日数对总降水日数变 化趋势的贡献最大, 两者均在2006 年发生突变, 转为急剧下降趋势。在空间分布上, 总降水日数和小雨日数总体分 布态势由西南向东北递减, 黔西南的大方、纳雍、水城等地为高值区, 黔东南以及东北局部地区为低值区; 中雨日数 和大雨以上日数则由东南向西北递减。不同地区降水日数以减少为主, 其中总降水日数和小雨日数在黔南地区减 少比较明显, 中雨日数呈减少趋势的比例高达90. 1%, 而大雨以上日数为增加趋势的比例较大( 44. 5%) , 呈条带状 分布, 主要在黔西、黔东北以及黔中南等地。

Based on the daily precipitat ion dat a at 81 meteo ro log ical stations in Guizhou Pro vince from 1961 to 2010, the spatial and tempo ral var iatio ns and abrupt chang e of r ainfall days w ith different int ensities wer e analyzed using the methods of linear trend analysis, Mann2Kenda ll test, and GI S spatial analy sis. T he results show ed that the r ainfa ll da ys w ith differ ent intensit ies incr ease g r adually fr om the 1960s to 1990s and decrease in the early 2000s, the total rainfall day s pr esent an o bv ious decreasing trend w ith a r ate of 1. 93 d/ 10a, and the light ra infa ll days acco unt for mo st o f to tal r ainfall days as both have an abrupt decrea2 sing trend in 2006. As fo r the spatial distr ibution, the total rainfall and lig ht rainfall days decr ease fr om southwest to nor theast wit h hig her2v alue centers in Dafang, Nayo ng , and Shuicheng in t he southwest and lower2value areas in the southeast and no rth2 east of Guizhou Prov ince, while the medium r ainfall and heavy r ainfall da ys decr ease from southeast t o nor thwest. The ra infall day s decr ease in different ar ea of Guizhou Pro vince. T he total rainfall and lig ht r ainfall days have a sig nificant ly decreasing trend in t he south of Guizhou Prov ince, the pr opor tion of mo der ate rainfall days show s a decr easing tr end of 90. 1%, and the area of heav y rainfall days w ith an increasing tr end acco unts for 67. 1% and is mainly located in the w est, nort heast, and south cent ral Guizho u Pro vince with a banding distributio n.

环保部公益性行业科研专项项目0 我国国土生态安全格局构建关键技术与保护战略研究0 ( 201209032)