Ice dynamics is an important factor affecting vegetation in high-altitude and high-latitude streams and rivers. During the last few decades, knowledge about ice in streams and rivers has increased significantly and a respectable body of literature is now available. Here we review the literature on how ice dynamics influence riparian and aquatic vegetation. Traditionally, plant ecologists have focused their studies on the summer period, largely ignoring the fact that processes during winter also impact vegetation dynamics. For example, the freeze-up period in early winter may result in extensive formation of underwater ice that can restructure the channel, obstruct flow, and cause flooding and thus formation of more ice. In midwinter, slow-flowing reaches develop a surface-ice cover that accumulates snow, protecting habitats under the ice from formation of underwater ice but also reducing underwater light, thus suppressing photosynthesis. Towards the end of winter, ice breaks up and moves downstream. During this transport, ice floes can jam up and cause floods and major erosion. The magnitudes of the floods and their erosive power mainly depend on the size of the watercourse, also resulting in different degrees of disturbance to the vegetation. Vegetation responds both physically and physiologically to ice dynamics. Physical action involves the erosive force of moving ice and damage caused by ground frost, whereas physiological effects - mostly cell damage - happen as a result of plants freezing into the ice. On a community level, large magnitudes of ice dynamics seem to favour species richness, but can be detrimental for individual plants. Human impacts, such as flow regulation, channelisation, agriculturalisation and water pollution have modified ice dynamics; further changes are expected as a result of current and predicted future climate change. Human impacts and climate change can both favour and disfavour riverine vegetation dynamics. Restoration of streams and rivers may mitigate some effects of anticipated climate change on ice and vegetation dynamics by, for example, slowing down flows and increasing water depth, thus reducing the potential for massive formation of underwater ice.

Assessing the uncertainties in modeling water temperatures during river cooling and freeze-up periods - ScienceDirect Skip to main contentSkip to article ## Cold Regions Science and Technology Date: June 2023 Article: 103840 ## Published by: Elsevier ### Published by Show more Research article Get rights and content # Assessing the uncertainties in modeling water temperatures during river cooling and freeze-up periods Jiaqi Yang, Yuntong She, Mark Loewen Show more Add to Mendeley More actions ## Highlights ## Keywords River water temperature simulation ; River1D ; River freeze-up ; Supercooling ; Heat transfer method ; Weather data - Previous article in this issue - Next article in this issue ## Introduction Most of the rivers in the northern hemisphere become supercooled as they lose heat to the colder overlying air in the fall or early winter. Frazil ice forms in the water column if the flow turbulence is sufficiently strong to entrain the surface supercooled water and ice crystals downward (Daly, 2013). The frazil ice crystals are in the “active” state when the river remains supercooled, and they tend to adhere to underwater objects forming anchor i

Ice in lakes and rivers - Formation, Movement, Melting | Britannica ice in lakes and rivers # Ice in rivers in # ice in lakes and rivers Ask Anything Homework Help Written by George D. Ashton Fact-checked by Britannica Editors Britannica AI Ask Anything Table of Contents Table of Contents Ask Anything ## Formation and growth ## Ice particles The formation of ice in rivers is more complex than in lakes, largely because of the effects of water velocity and turbulence. As in lakes, the surface temperature drops in response to cooling by the air above. Unlike lakes, however, the turbulent mixing in rivers causes the entire water depth to cool uniformly even after its temperature has fallen below the temperature of maximum density (4° C, or 39° F). The general pattern is one in which the water temperature fairly closely follows the average daily air temperature but with diurnal variations smaller than the daily excursions of air temperature. Once the water temperature drops