在公河下流盆地每年峰值排放的频率和趋势分析
Uttam Pawar1, Sophal Try2, Nitin Muttil3
1Department of Geography, HPT Arts and RYK Science College, Nashik, 422 005, Maharashtra, India.
Heliyon
|October 9, 2023
概括
在公河下游盆地,每年的洪水峰值显示出明显的下降趋势,尽管存在差异. 洛格-皮尔森型III分布最适合用于洪水频率分析,有助于灾害管理.
科学领域:
- 水文学的水文学
- 气候科学 气候科学
- 环境管理环境管理
背景情况:
- 人为影响和气候变化显著影响每年排放的峰值,这对灾害管理至关重要.
- 了解公河下流盆地 (LMB) 洪水趋势对于有效的规划和减缓至关重要.
研究的目的:
- 分析LMB的年度最大系列 (AMS) 排放和洪水频率的趋势.
- 确定最适合在该地区进行洪水频率分析的概率分布.
主要方法:
- 通过公河委员会从LMB的五个站点采购AMS数据.
- 应用曼-肯达尔测试来评估年度高峰洪水的趋势.
- 用于比较Log-Pearson Type-III (LP-III) 和Gumbel极值类型I (GEVI) 分布的适合性测试.
主要成果:
- 曼 - 肯德尔测试表明,在LMB的所有排放测量站点,每年峰值洪水的大小显著下降.
- 分析揭示了年度峰值排放的显著变化和偏离 (正面和负面).
- 罗格-皮尔森型III (LP-III) 被确定为公河AMS数据的优越分布.
结论:
- 该研究证实了年度峰值排放和洪水频率的持续趋势,支持LP-III对预测的可靠性.
- 调查结果为LMB的水资源管理,洪水灾害控制和规划提供了可靠的基础.
- 鉴定的趋势对于适应不断变化的水文条件和减轻洪水风险至关重要.
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