基于GIS技术的洪水淹没计算分析系统建立与应用

ESTABLISHMENT AND APPLICATION OF FLOOD DISASTER ANALYSIS SYSTEM BASED ON GIS

洪水淹没范围的计算分析是防汛救灾管理和灾害损失评估的核心任务,而利用高新技术对洪水进行监测管理、计算分析和灾害损失评估,一直是防汛应急管理工作的薄弱环节。为此,探讨防洪流域洪水淹没计算分析系统的解决方案和实现方法,对应用系统的软硬件环境、体系结构、系统内容、系统功能和技术特点等进行详细说明,采用较为成熟的模型技术和计算机手段,研究建立基于GIS技术的洪水淹没计算分析系统,实现多源数据管理、洪水演进模拟、淹没范围计算和灾害损失评估等功能,并在海子水库防汛救灾管理工作中运行良好。应用结果表明:所采用的技术方法和分析模型能准确地计算模拟洪水淹没范围;洪水淹没面积的计算精度以及灾害评估和预测分析的准确性主要取决于空间数据精度的优劣和相关统计数据的完备程度。

The simulation of flood routing and the computation of flooded areas are key tasks for flood control, damage estimation and emergency management. Meanwhile, it is necessary and possible to apply numerical simulation, database and GIS technologies in the research field of flood-control management as well as to the computation and analysis of flooded area simulation by GIS. This paper, taking the lower reaches of Haizi reservoir basin as an example, discusses the application of approaches and methods of GIS in the computation of flooded area and in the establishment of flooding analysis system for flood prevention and mitigation. At first, software and hardware environment, system structure, contents, main functions and technical characteristics of application system are expounded. Then, on the basis of obtained data, p＇resent work and current resources, a GIS-based flooding analysis system was established by adopting numerical simulation, digital elevation model. The system realized such major functions as map manipulation, information query, information management of hydraulic structure behavior, computation and analysis of flooded areas, management of flood control, information issuance and statistical output, which was characterized with composite structure of Client/Server mode and Browser/Server mode, massive data management, meta-data organization and modular development. In addition, the system was applied for the flood control and mitigation management of the reservoir valley for Beijing bureau of water resources. At last, it is concluded that the adopted technical methods and numerical model can simulate flood routing, ＂compute flooded areas and assess flooded losses, thus providing a scientific basis for the fast assessment of flooded losses and decision-support service of flood control, and that the computation precision of flooded areas and the veracity of disaster loss assessment and forecast are mainly dependent on the quality of spatial data and the complete extent of relative statistical data.