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An Appraisal to Anthropogeomorphology of the Bhagirathi-Hooghly River System
Published in Balai Chandra Das, Sandipan Ghosh, Aznarul Islam, Suvendu Roy, Anthropogeomorphology of Bhagirathi-Hooghly River System in India, 2020
Balai Chandra Das, Sandipan Ghosh, Aznarul Islam, Suvendu Roy
The dominant form of direct human-induced disturbance to river courses reflects sachems that have endeavoured to control and regulate their flow and associated concerns for water supply, whether for agricultural (irrigation), commercial/industrial or residential purposes (Brierley and Fryirs, 2005; Wohl, 2014). Enormous effects have been undertaken to make dry lands wetter and wet lands drier, ensuring that water is available for human purposes. The extent of these programs is staggering. The global volume of freshwater trapped in reservoirs now exceeds the volume of flow along rivers (Brierley and Fryirs, 2005). Surely, dam construction has played a major part in pivotal societal changes, such as the development of hydraulic civilisations. Although dams have been constructed for more than 5000 years, the pace of construction quickened dramatically after the Second World War, and each year more than 200 large dams are completed. Reservoirs, dams and diversions are vital for securing water supplies and controlling floods, but the changes in fluvial processes they impose on downstream rivers, dominated by reduced sediment loads and lower flood magnitudes, can be dramatic (Petts and Gurnell, 2013).
The application of hydrogeomorphological tools to improve agricultural watershed management in Quebec (Canada)
Published in Wim Uijttewaal, Mário J. Franca, Daniel Valero, Victor Chavarrias, Clàudia Ylla Arbós, Ralph Schielen, Alessandra Crosato, River Flow 2020, 2020
N. Stämpfli, P.M. Biron, W. Massey
In the Bulstrode River watershed, whereas many local attempts have been made to stabilize actively migrating banks, the current channel mobility was shown to be generally natural, and in line with historical values. The river’s mobility, however, could be exacerbated in some reaches by anthropogenic activities, including poorly designed bank stabilization structures. Sediment generation could potentially be reduced by implementing best management cropping and water management practices in the watershed’s agricultural areas, but also by ensuring sufficient space in the floodplain for fluvial processes to take place, especially in the most active reaches. The potential sediment input from unpaved roads and ditches, which are common in steep tributary watersheds of the Bulstrode River, should also be investigated.
Mechanics of biofilm-coated sediment transport
Published in Silke Wieprecht, Stefan Haun, Karolin Weber, Markus Noack, Kristina Terheiden, River Sedimentation, 2016
H.W. Fang, H.M. Zhao, W. Cheng, M. Fazeli, Y.S. Chen, Q.Q. Shang, G.J. He, L. Huang
Sediment dynamics are especially important in fluvial processes. After the impoundment of the TGR, high nutrients and weak hydrodynamic conditions provide favorable circumstances for biofilm growth, which would significantly change the sediment properties and the corresponding transport dynamics. In this paper, a biomass dynamics model, including the accrual term and detachment term (velocity-dependent and/or autogenic), was proposed to study the biofilm growth on sediment. Then the bedform induced by the flow and its resistance, as well as the changes of the settling velocity and incipient velocity after the biofilm growth were addressed for a better understanding of the suspension and transport of the biofilm-coated sediment. Moreover, the bed-load and suspended-load transport for bio-sediment were also derived. These studies will contribute to a better management of the water and sediment resources in the reservoir, and give insight to evaluate the ecological effects in and downstream the reservoir.
Intergovernmental cooperation on the Amur River basin management in the twenty-first century
Published in International Journal of Water Resources Development, 2018
Eugene Simonov, Eugene Egidarev
In January 2014, at the 6th meeting of China-Russia Transboundary Water Joint Commission, the Working Group on Water Resources Management was tasked to conduct research and produce a joint report on the 2013 flood on the Amur River, which was approved by the Joint Commission in 2015 (Sino-Russian Working group, 2015). The report calls for establishing a basin-scale coordination mechanism and optimizing the regulation of existing large reservoirs. It suggests carrying out the following cooperating work in flood control step by step:Strengthen the establishment of a hydrological monitoring network.Enhance information sharing.Share methodologies and enhance cooperation on hydrological forecasting in the Amur River basin, including cooperation on development of an Amur River basin hydrological model and flood forecasting operating system.Conduct joint research on fluvial processes, impacts of human activity and large hydraulic engineering structures, and impacts on the floodplain and the ecological environment of changes in flooding and fluvial process.
Hydraulic drivers of populations, communities and ecosystem processes
Published in Journal of Ecohydraulics, 2021
Aaron I. Packman, Christopher T. Robinson, Nicolas Lamouroux
The knowledge needed to effectively protect and restore river ecosystems has proven difficult to obtain and translate into practice for river management and hydraulic engineering. While many fluvial processes have been studied individually, it is extremely difficult to predict the long-term consequences of simultaneous changes in climate, land use, and river management on aquatic ecosystems. Consequently, there is considerable uncertainty in the long-term outcomes of key processes that structure river ecosystems, such as changing river flow conditions; inputs of sediments, nutrients, and terrestrial organic matter; and the spatiotemporal distribution of connectivity between rivers and fringing habitats including hyporheic, riparian, and floodplain environments. Increased recognition of these ecological challenges and the potential for even greater modification of fluvial systems in the future has driven greater interest in conservation, restoration, and resilience measures to protect the biodiversity, ecological functioning, and societal benefits of fluvial systems. Individual river conservation and restoration efforts have a wide range of objectives. Consequently, distinct solutions have been proposed for biodiversity conservation, stormwater retention, seasonal water storage, and nutrient management (Nienhuis and Leuven 2001; Angelopoulos et al. 2017; Roy et al. 2018; Weber et al. 2018). As with the complexity of understanding current challenges to aquatic ecosystems, it is difficult to ascertain the long-term outcome of multiple conservation and restoration efforts within an individual aquatic system (Friberg et al. 2016; Lorenz et al. 2018), and little progress has been made in synthesizing information on key environmental drivers of ecological responses into holistic measures for river management (Palmer and Ruhi 2019; Roni 2019).
LSPIV measurements to assess the impact of a bridge on a weakly undulating flow
Published in Journal of Applied Water Engineering and Research, 2023
Matías Eder, Leticia Tarrab, Román Martino, Leandro Masso, Antoine Patalano, Matías Ragessi, Gerardo Hillman, Andrés Rodriguez, Mariana Pagot
Studies regarding the hydro-environmental impact of hydraulic structures on fluvial processes play a key role in understanding how the interaction between complex flow fields and obstacles alters the hydrodynamics of streams and rivers. Research work, developed in physical models as well as in the field, has pointed out the relevance of measuring the behavior of the whole system. Data registered in such large domains is essential in validating numerical models. Large-scale PIV is a non-intrusive technique that has shown to be a reliable, useful tool to provide the planimetric flow distribution at the free surface of the flow at reach scale, and with a high spatial resolution (Fujita et al. 1998). Measurements of the instantaneous free-surface velocity fields provide information of flow patterns, vorticity, streamlines, mean velocity gradients, the generation and evolution of large coherent structures, and allow identification of regions of flow stagnation and separation, helping studies regarding sediment deposition and bank erosion (Muste et al. 2008; Lewis and Rhoads 2015; Creëlle et al. 2018). LSPIV offers an advantage over single-point measurements, which are time, cost, and labor-intensive when applied to measure a grid with high-spatial resolution. Acoustic Doppler velocimeter (ADV), acoustic Doppler current profiler (ADCP), mechanical/electromagnetic current meter, or pitot tube require a minimum water depth to accommodate the remote sampling volume or deploy the probe. Thus, such instruments cannot measure the free-surface velocity profiles. LSPIV is well-suited to measure broad, shallow flows under large-scale laboratory or field conditions (Muste et al. 2014) and has been extensively applied to various laboratory models studying bridge scour, approaching flow to power plant spillways, and other hydraulic structures (Lewis and Rhoads 2015). There was also applied to measure large coherent structures arising in shallow wake flows behind obstacles and shallow, mixing layers (Kantoush et al. 2011). Velocities measured with LSPIV, in conjunction with bathymetry information and assuming a velocity distribution in the flow depth, allow estimation of flow discharge. Since it is a safe, non-intrusive technique that provides continuous measurements over large timespans, it constitutes a standard method for monitoring environmental flows (Dobriyal et al. 2017).