评估特定河流中目标鱼类息地的环境流动
1Chittagong University of Engineering and Technology, Chattogram, Bangladesh.
Heliyon
|February 20, 2025
概括
环境流量 (EF) 评估对于维持鱼类息地和饮用水源至关重要. 这项研究发现,哈尔达河的低干旱季流量威胁到水生生物和鱼产卵,而帕德玛河的流量下降到临界水平以下.
科学领域:
- 环境科学 环境科学
- 水文学的水文学
- 渔业管理 渔业管理 渔业管理
背景情况:
- 帕德玛,卡纳富利和哈尔达河是达卡和查托格拉姆的重要水源,支持大量的海尔沙和鱼渔业.
- 保持足够的环境流 (EF) 对水生息地和供水至关重要,平衡人类需求与生态要求.
- 特定的水深和溶解氧 (DO) 水平对于海尔沙鱼和鱼种群的生存和生长至关重要.
研究的目的:
- 评估帕德玛河,卡纳富利河和哈尔达河对鱼类息地和饮用水供应的环境流量 (EF) 要求.
- 为了确定这些关键河流系统的平均年流量 (MAF),并模拟这些关键河流系统的水质参数.
- 为孟加拉国有效的水资源管理提供支持决策支持系统 (DSS) 的数据.
主要方法:
- 长期实地采样和对历史二次数据的分析.
- 现场和实验室测试水质参数,包括溶解氧 (DO).
- 水文工程中心的河流分析系统 (HEC-RAS) 对流量和水质进行模拟.
主要成果:
- 在干旱季节,帕德玛河的流量下降到MAF的20%以下,可能会损害水生生物;DO水平保持在6.0 mg/L以上.
- 哈尔达河和卡纳富利河在干旱季节保持水面最低水位为2.35-2.40米.
- 哈尔达-卡纳福利河的DO水平每年都低于可接受的限值;哈尔达河的流量减少到不到MAF的10%,降低了水生生物的水平,并阻碍了鱼的产卵.
结论:
- 在干旱季节,哈尔达河的环境流量极度低,对其水生生态系统和鱼产卵构成严重威胁.
- 虽然帕德马河的DO水平一般是充足的,但流量减少带来了风险;哈尔达-卡纳富利河面临着严重的DO赤字.
- 该研究为Hilsha和Carp息地提供了重要的EF数据,这对于开发可持续的水资源管理战略和支持DSS至关重要.
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