我国干旱区洪水灾害基本特征──以新疆为例

BASIC FEATURES OF THE FLOOD DISASTERS IN ARID LAND OF CHINA: TAKING XINJIANG AS AN EXAMPLE

依据新疆自然和社会环境，分析了新疆洪水及其洪灾的形成、季节分布、年际变化、地区分布等主要特征，并提出对洪水灾害的防御对策。

The formation of floods and their disasters in Xinjiang is analyzed in the paper based on the physiographical conditions and social environment. According to the causes and fea tures of the floods and their disasters, they are classified into ice-snow-melting flood disasters, rainstorm flood disasters, mixing flood disasters of ice - snow - melting and rainstorm, and various flash floods. According to the statistical data of 1953 big floods oc curred in the main rivers in Xinjinag, ice-snow-melting floods, rainstorm floods, mix ing floods of ice - snow-melting and rainstorm, and various flash occupy 39%, 24%, 34% and 3% of the total respectively.Although rainstorm floods occupy only 24% of the total in Xinjiang, the floods occur ring the summer in the middle and small sized rivers and small gullies fed mainly by rain storm water are almost rainstorm floods according to the analyzed data of occurring date,duration and route of the rain scope, precipitation, etc. Therefore, rainstorm flood in the main flood type in Xinjiarrg. The big flood disasters are mainly caused by rainstorms due to their flash occurrance, big amount of silt discharge, and violent destruction. The loss caused by rainstorm flood disasters takes over 63% of the total loss caused by various flood disasters in Xinjiang.The seasonal and regional distribution and annual variation of the flood disasters in Xinjiang are also discussed, and some countermeasures are put forward in the paper.