Browsing All Posts filed under »hydraulics«

Understanding how fish benefit from river restoration

January 14, 2019

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Although relationships between fish traits and environmental factors are well known, there have been few attempts to use fish traits to interpret the outcomes of stream restoration projects.  German scientists set out to do this by analyzing  data from a tributary of the Rhine River, which had a long history of channelization, bank fixation, riparian […]

Turbulent times for freshwater plants

January 14, 2019

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Water movement is one of the most important factors affecting the distribution of aquatic plants, and has a beneficial or detrimental impact  depending on the magnitude of flow.  Japanese researchers compared the effects of steady flow and turbulence on three plant species with different types of morphology: western waterweed (Elodea nuttallii) with whorled leaves, curly-leaved […]

A clearer picture of suspended sediment

October 8, 2018

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Because many pollutants adsorb onto the surfaces of fine sediment particles, sediment transport plays a central role in distributing contaminants throughout river systems.  However, current models of sediment and pollutant transfer are complex and complicated by the fact that key processes such as adsorption, erosion and deposition aren’t easily  observed.  Belgian scientists have responded to […]

Simplifying urban stream assessment

December 21, 2017

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Urban streams experience high levels of stormwater runoff and channel erosion, and represent a significant challenge for ecological restoration.  Nevertheless, it’s generally agreed that urban stream restoration should aim to mimic the natural (pre-development) flow regime as closely as possible.  It’s been proposed that ecologically important aspects of flow can be used as a basis […]

Erasing the boundaries

June 19, 2017

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The new discipline of ecohydraulics considers the effects of water movement in aquatic ecosystems and blends ideas and techniques from aquatic ecology and engineering hydraulics. A central challenge for ecohydraulics is to reconcile differences between hydraulic engineers and ecologists in terms of the spatial and/or temporal scale of the processes that they tend to deal […]

Flow-on effects of water movement

March 23, 2016

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Although aquatic plants risk being uprooted in fast-flowing streams, if they’re capable of varying their growth form to suit the conditions they may be able to reduce the chance of dislodgement. To see if water plants can adapt to fast-moving water by increasing their strength and reducing their drag, Swedish researchers compared the growth of […]

Stream-bed stability: differing effects of floods

December 18, 2015

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Floodwaters are often released from dams to rejuvenate channel form and aquatic habitats, but in the process, large volumes of sediment can be transferred downstream. Therefore, especially in the case of rivers where the sediment supply is limited, it’s useful to be able to predict how different flows affect particle mobilisation and retention. In a […]