埃塞俄比亚阿比贾塔-朗格诺-齐瓦伊湖流域的地下水流系统,埃塞俄比亚
Debele Abera1, Behailu Berehanu2, Tenalem Ayenew2
1Department of Natural Resources Management, College of Agriculture and Environmental Sciences, Arsi University, P.O. Box:193, Asella, Ethiopia.
Heliyon
|December 19, 2024
概括
一个数值地下水流量模型准确地模拟了埃塞俄比亚阿比贾塔-兰戈诺-齐韦湖盆地的水动力学. 这种工具对于在气候变化和过度开采等挑战中管理水资源至关重要.
科学领域:
- 水文地质学 水文地质学
- 环境科学 环境科学
- 水资源管理 水资源管理
背景情况:
- 埃塞俄比亚主要埃塞俄比亚裂中的阿比贾塔-兰戈诺-齐韦湖盆地 (ALZLB) 面临水资源挑战,原因是土地利用变化,人口增长和气候脆弱性.
- 了解地下水的动态对于这个复杂的盆地有效的水资源管理至关重要.
研究的目的:
- 为ALZLB开发和校准一个数值地下水流量模型.
- 描述地下水流系统及其与地表水体的相互作用.
- 评估模型在代表盆地的水文地质学方面的准确性.
主要方法:
- 使用MODFLOW数值模型创建盆地的水文地质学的数学表示.
- 利用稳定状态的数值计算,将概念的水文地质模型转化为定量模型.
- 嵌入的参数,如液压导电性和地下水流入和流出的边界条件.
主要成果:
- 校准模型与观察到的地下水位 (R2 = 0.98,NSE = 0.97) 显示出极好的一致性.
- 地下水补充和恒定头部边界被确定为主要流入源 (445万/年和90万/年).
- 恒定头部边界是主要的流出通道 (519万米/年),水平衡近乎完美 (-0.75%的差异).
结论:
- 数值地下水流量模型准确地代表了ALZLB地下水系统的平稳状态条件.
- 该模型的高精度为了解和管理盆地的水资源提供了可靠的工具.
- 通过从这个校准模型中获得的见解,可以制定有效的水资源管理策略.
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