School of Water Conservancy Engineering, Zhengzhou University, Zhengzhou 450001, China.
School of Water Conservancy Engineering, Zhengzhou University, Zhengzhou 450001, China.
Sci Total Environ. 2022 Sep 1;837:155853. doi: 10.1016/j.scitotenv.2022.155853. Epub 2022 May 11.
Dam-break floods cause substantial damage to the environment, and evaluating the negative impacts of dam-break floods on the environment (EI) is an important part of flood risk management. EI has been evaluated using various methods with different indices. However, the evaluation results of EI are typically one-sided or inaccurate because of diverse indices and complex influencing factors. A new method was proposed herein to calculate EI with an index system, including geomorphic changes (GC), water pollution (WP), plant biomass loss (PB), and biodiversity loss (BL). Eight factors that influence EI were sorted out, namely, erosion or deposition depth, non-point source (NPS) and point source (PS) pollution, plant biomass, species richness, plant height, and flood depth, velocity, and duration. After combining the proposed damage functions to calculate the influence of flood depth, velocity, and duration, and plant height on the environment, methods to calculate GC, WP, PB, BL, and EI were proposed. A dam-break flood scenario for Luhun Reservoir was used to verify the method. The results showed that (1) the trend in EI was similar to that in geomorphic changes in the inundated area and seriously affected by PS in local areas, (2) the average EI of woodland was the highest, while that of towns was the slowest, and (3) GC and WP contributed 93.7% of EI in the entire inundated area. This study summarized the complex impacts of dam-break floods on the environment from four aspects and proposed a method to quantify the overall impact of dam-break floods on the environment. The evaluation model could evaluate the impact of floods on the environment accurately, presenting the results on a flood inundation map. This provides a scientific basis for evaluating flood consequences and managing flood risk.
溃坝洪水会对环境造成重大破坏，评估溃坝洪水对环境的负面影响（EI）是洪水风险管理的重要组成部分。EI 已使用具有不同指数的各种方法进行了评估。然而，由于指数的多样性和复杂的影响因素，EI 的评估结果通常是片面的或不准确的。本文提出了一种新的方法，用一个包含地貌变化（GC）、水污染（WP）、植物生物量损失（PB）和生物多样性损失（BL）的指数系统来计算 EI。确定了影响 EI 的 8 个因素，包括侵蚀或沉积深度、非点源（NPS）和点源（PS）污染、植物生物量、物种丰富度、植物高度以及洪水深度、流速和持续时间。在结合提出的损伤函数来计算洪水深度、流速和持续时间以及植物高度对环境的影响后，提出了计算 GC、WP、PB、BL 和 EI 的方法。利用陆浑水库的溃坝洪水情景对该方法进行了验证。结果表明：(1)EI 的趋势与淹没区地貌变化的趋势相似，并且严重受到局部地区 PS 的影响；(2)林地的 EI 平均值最高，而城镇的 EI 平均值最慢；(3)GC 和 WP 对整个淹没区的 EI 贡献了 93.7%。本研究从四个方面总结了溃坝洪水对环境的复杂影响，并提出了一种量化溃坝洪水对环境的整体影响的方法。该评价模型可以准确地评价洪水对环境的影响，并在洪水淹没图上呈现结果。这为评估洪水后果和管理洪水风险提供了科学依据。
