Scholarlink

<p>Rivers keep their ecosystems alive through the timing of their flows and the mix of habitats they form. In this study we looked at how a few large dams have changed the flow and shape of two very different rivers in India — the Sone, which runs through an alluvial plain, and the Narmada, which cuts mostly through rock. From the River Flow Health Index (RFHI) we could see that both systems have been altered below the dams. The Bansagar section had an RFHI value of about 0.77, and the Indira Sagar–Omkareshwar reaches around 0.76, showing that the flows are no longer close to natural. In the Sone, diminished peak flows over the past forty years have decreased the width of the main channel from approximately 1.24&#xa0;km to 0.82&#xa0;km, a reduction of nearly one-third. In addition, new mid-channel bars have formed, leading to an increase in the braid ratio from 1.21 to 1.37, and an increase in the bar density from 0.32 to 0.57 bars/km. The floodplain also less frequently connects to the river than in the past (0.76 → 0.54), and in the process, many regions that were previously important for gharial nesting have been isolated. The Narmada, in contrast, has a consistent width (0.95–0.98&#xa0;km), a similar sinuosity (≈ 1.26), and a stable bar density (≈ 0.21–0.24 bars/km), but its floodplain decreased from 0.69 to 0.43. The reduction of over-bank flow means less saturated areas for the riparian zone and for plants of medicinal value. In summary, the Sone has a rapid temporal response to flow alterations, while the Narmada changes little in morphology but experiences greater ecological withdrawal. For dam management, this is a significant difference because hydropower and irrigation can be mismatched to the geology of the area, while living rivers must be maintained downstream.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Anthropogenic Interventions in Diverse Watersheds: Insights for Sustainable Water Resource Management

  • 期刊论文

  • 发表日期：

    2025年12月29日

查看全文
  • Maithili Mohanty,
  • Vinod Tare

摘要

Rivers keep their ecosystems alive through the timing of their flows and the mix of habitats they form. In this study we looked at how a few large dams have changed the flow and shape of two very different rivers in India — the Sone, which runs through an alluvial plain, and the Narmada, which cuts mostly through rock. From the River Flow Health Index (RFHI) we could see that both systems have been altered below the dams. The Bansagar section had an RFHI value of about 0.77, and the Indira Sagar–Omkareshwar reaches around 0.76, showing that the flows are no longer close to natural. In the Sone, diminished peak flows over the past forty years have decreased the width of the main channel from approximately 1.24 km to 0.82 km, a reduction of nearly one-third. In addition, new mid-channel bars have formed, leading to an increase in the braid ratio from 1.21 to 1.37, and an increase in the bar density from 0.32 to 0.57 bars/km. The floodplain also less frequently connects to the river than in the past (0.76 → 0.54), and in the process, many regions that were previously important for gharial nesting have been isolated. The Narmada, in contrast, has a consistent width (0.95–0.98 km), a similar sinuosity (≈ 1.26), and a stable bar density (≈ 0.21–0.24 bars/km), but its floodplain decreased from 0.69 to 0.43. The reduction of over-bank flow means less saturated areas for the riparian zone and for plants of medicinal value. In summary, the Sone has a rapid temporal response to flow alterations, while the Narmada changes little in morphology but experiences greater ecological withdrawal. For dam management, this is a significant difference because hydropower and irrigation can be mismatched to the geology of the area, while living rivers must be maintained downstream.