基于信息量模型的新疆额尔齐斯河流域春季融雪洪水危险性评价

Evaluation of Spring Snowmelt Flood Hazard in the Xinjiang Ertix River Basin Based on Information Quantity Model

摘要:

额尔齐斯河是新疆第二大河,同时也是一条国际河流,其水资源对我国新疆以及哈萨克斯坦、俄罗斯等国家的社会经济发展具有重要的意义。随着全球气候变暖，新疆额尔齐斯河流域春季融雪型洪水频发，对当地居民生活、农业生产、基础设施和生态环境构成严重威胁。基于融雪型洪水发生机理，选取积雪深度、高程、地势起伏度、坡度、水系距离和土地利用类型6个关键因子，结合历史灾情数据，应用信息量模型对春季融雪型洪水危险性进行定量评价和区划。研究发现：1）额尔齐斯河流域春季融雪型洪水多发生在海拔1500 m以下山前平原和河流附近的草地、耕地和居民用地区域；2）积雪深度和水系距离是影响春季融雪型洪水危险性的重要因素。积雪深度在40～50 cm、水系距离在1～2 km的区域洪水发生风险尤为显著；3）5组随机实验模型平均AUC值0.86，验证了基于选定的6个关键指标因子，应用信息量模型评价额尔齐斯河流域春季融雪型洪水危险性的有效性。研究成果可为额尔齐斯河流域春季融雪型洪水防治措施和水资源管理提供依据，为类似地区融雪型洪水危险性评价提供参考。

Abstract:

The Ertix River, the second largest river in Xinjiang and an international watercourse, is crucial for the socio-economic development of Xinjiang, China, as well as Mongolia and Kazakhstan. With global climate warming, spring snowmelt floods in the Ertix River Basin are increasing in frequency, posing severe threats to local communities, agricultural production, infrastructure, and the ecological environment. This study identifies six key factors influencing snowmelt flood occurrence: snow depth, elevation, topographic ruggedness, slope, distance to water systems, and land use types. By integrating historical disaster data with an information quantity model, we quantitatively evaluated and zoned the hazard of spring snowmelt floods. The findings indicate: 1) Spring snowmelt floods predominantly occur in the piedmont plains below 1500 meters elevation and near rivers, particularly in grasslands, farmlands, and residential areas; 2) Snow depth and distance to water systems are critical factors, with areas having snow depths between 40-50 cm and distances to water systems between 1-2 km exhibiting the highest flood risks; 3) The average AUC value of 0.86 from five sets of random experimental models confirms the effectiveness of the information quantity model in evaluating the hazard of spring snowmelt floods based on the six selected key indicators. This study provides a scientific basis for developing flood prevention measures and water resource management strategies in the Ertix River Basin and offers a reference for assessing snowmelt flood hazards in similar regions.