The reservoirs of the dams and barrages are largely ignored in terms of the assessment of Ecosystem Services (ES) compared with other types of wetland. It is undoubtedly due to many adverse impacts of dam impoundment. However, stored water into the reservoirs gradually forms a significant wetland to enrich the biodiversity and support the essential ES. This research presents a comprehensive analysis of ES provided by the reservoir-based Gazaldoba Barrage Wetland (GBW) in the Himalayan foothills on the river Tista in India. The study integrated qualitative and quantitative approaches to prepare an assessment framework to evaluate the ES of GBW, principally based on four indicators, sub-divided into 11 broad categories and further sub-divided into 11 sub-categories of benefits and challenges. The ES were assessed in two perspectives: first, the study identified, measured and described the ES; second, it recognized the immediate challenges to sustain the ES along with the potential challenges created by the operation of the barrage itself.

The assessment identified the significant role of GBW in extending ES to the riparian communities. GBW plays a vital role in controlling 5% of peak flood flow and can cover a 0.92 million ha target area for irrigation. The reservoir water supports 80 bird species and 81 plant species and attracts many tourists, generating >1000 employments and approximately $ 1.2 million as annual revenue. In contrast, ES are sensitive to >84% of water level variations. Recent sedimentation (∼19 million metric tons in reservoir and canal) reduced the reservoir capacity and diversion capacity by 7%. The high diurnal flow (3–4 h) varies >70 times of the low diurnal flow due to upstream regulations, affecting the ES of GBW. Moreover, spatial variations in access to ES of GBW influence the development of differential perceptions among riparian communities, while GBW is vulnerable to increasing water demand and the geopolitics of future water sharing. Such systematic assessments based on a framework are significant for future policies and management of the river ecosystem to ensure the benefits of services for the riparian communities across the basin.

与其他类型的湿地相比，在生态系统服务 (ES) 评估方面，大坝和拦河坝的水库在很大程度上被忽略了。这无疑是由于大坝蓄水带来的诸多不利影响。然而，储存在水库中的水逐渐形成了一个重要的湿地，以丰富生物多样性并支持必要的生态系统。本研究对印度蒂斯塔河上喜马拉雅山麓的基于水库的 Gazaldoba 拦河坝湿地 (GBW) 提供的 ES 进行了综合分析。该研究整合了定性和定量方法，以制定评估框架来评估 GBW 的 ES，主要基于四个指标，细分为 11 个大类别，并进一步细分为 11 个子类别的收益和挑战。从两个角度对 ES 进行评估：第一，该研究确定、测量和描述了 ES；其次，它认识到维持 ES 的直接挑战以及由拦河坝本身的运作所带来的潜在挑战。

评估确定了 GBW 在将 ES 扩展到河岸社区方面的重要作用。GBW 在控制 5% 的洪峰流量方面起着至关重要的作用，可以覆盖 92 万公顷的灌溉目标区域。水库水支持 80 种鸟类和 81 种植物，吸引了许多游客，创造了 1000 多个就业机会和大约 120 万美元的年收入。相比之下，ES 对 >84% 的水位变化敏感。最近的沉积（水库和运河约 1900 万吨）使水库容量和导流能力降低了 7%。由于上游法规，高日流量（3-4 小时）变化大于低日流量的 70 倍，影响 GBW 的 ES。此外，获得 GBW 的 ES 的空间变化影响了河岸社区之间不同看法的发展，而 GBW 容易受到不断增长的用水需求和未来水资源共享的地缘政治的影响。这种基于框架的系统评估对于河流生态系统的未来政策和管理具有重要意义，以确保整个流域沿岸社区的服务收益。