关键词: 黄河流域, 长江流域, 雨涝, 受灾率

Abstract: Based on the statistical information of meteorological and agricultural inundation disaster data from 1951 to 2006, the characteristics of the spatial and temporal distribution of the occurrence frequency of rain-waterlogging process (defined as 10-day accumulated rainfall ≥250 mm (150 mm in Northwest China) or 20-day accumulated rainfall ≥350 mm (250 mm in Northwest China)) in the Yellow River and the Yangtze River basins were analyzed, the results show that rain-waterlogging in the two river basins has continually increased during the last 50 years, especially after the 1980s due to the impact of climate change; inundated cropland areas and economic losses showed increasing trends. The rain-waterlogging range was larger and the occurrence frequency of rain-waterlogging was higher in the Yangtze River basin in comparison with the Yellow Rive basin. Summer was a season in one year when the occurrence frequency of rain-waterlogging was the highest and its range was the largest due to the influence of rainstorms. Since the end of the 1980s, rainstorm disaster has distinctively increased in the Yellow Rive basin, and since the early 1980s inundated cropland area has remarkably increased in the Yangtze River basin. The inundation ratios of rain-waterlogging in the two river basins gradually increased from the upper reaches to lower reaches, and the impacts of rain-waterlogging disaster were relatively larger in the middle and lower reaches of the Yangtze River basin.

Key words: Yellow River basin, Yangtze River basin, rain-waterlogging, inundation ratio, disaster