中文摘要：

根据降雨对内河航运影响的特点，将影响程度划分为轻微影响、一般影响和明显影响三个等级。利用长江中游干线17个站点19652008年的降雨数据，结合小波分析方法，研究了该地降雨对航运不同程度影响的气候变化特征。研究结果表明：降雨对航运业造成明显影响的频次较多且随时间波动大；降雨造成的各等级影响频次均具有微弱的下降趋势，气候倾向率的绝对值都〈0．3d／10a；各等级影响频次变化的时间周期震荡大致相同，均为20a左右，且周期分界点大致相同；由小波周期可以预测，未来15a内各等级影响的频次均将处于偏多时期，降雨将更加频繁地对航运业造成影响。

英文摘要：

According to the features of rainfall effects on inland water navigation, the influence degree is defined as three levels, i.e. light, ordinary and high level. Based on the daily observational precipitation data from 17 stations in middle reach of the Yangtze River trunk from 1965 to 2008, the climate variation characteristics are studied from the view angle of the effects on Yangtze shipping by using wavelet and statistical analysis method. The results indi- cate that the high level rainfall influence on shipping happens in relatively high frequency though fluctuates from year to year. It is also found that the frequencies of all level influences happening show a slightly decreasing trend with the rate less than 0.3 d/10 a. The frequencies for all influence levels oscillate in similar period around 20 a. The Wavelet period predicts that the rainfall influence frequency of all levels will rise, implying that rainfall will affect the Yangtze shipping more frequently, in the next 15 years.