Browsing All Posts filed under »sediment«

Coarse, shallow and wooden… but useful nonetheless

June 19, 2017

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Coarse woody debris (CWD) derived from shoreline trees provides an important, spatially complex habitat and a food source for lake-dwelling organisms. Here are some interesting facts about lake CWD, taken from a recent review paper: In the absence of the physical action of flowing water, CWD breaks down more slowly in lakes than in streams. […]

A disturbing mix

June 19, 2017

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The common carp (Cyprinus carpio) has been introduced to many locations around the world and is highly invasive.  Its habit of foraging by digging in the bottom substrate significantly alters freshwater systems by uprooting plants, resuspending sediment, and increasing turbidity and the release of nutrients.  However, the extent to which aquatic nutrient flows are affected […]

Planting vegetation to stop stream bank erosion: where’s the evidence?

June 19, 2017

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Increased rates of stream bank erosion and sediment movement in disturbed catchments have been attributed to changes in catchment hydrology caused by land clearing, channel modification, the trampling activities of livestock and the removal of riparian vegetation. Given that these effects are human-induced, it’s commonly assumed that they can also be reversed by human intervention, […]

Dealing with river complexity

March 27, 2017

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Hydromorphology is a relatively new field that deals with the structure of hydrological systems and changes in their form over time. Many such changes are influenced by human-induced pressures. Realistic attempts to conceptualize hydromorphological forms and processes reflect the fact that rivers are complex multidimensional systems with longitudinal, lateral, vertical and temporal components, as well […]

Emergent wetland plants as conduits for methane

December 13, 2016

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Wetlands release more methane to the atmosphere than other any other type of ecosystem and wetland plants, especially those in the shallow fringing zones, play an important role in methane dynamics. However, aquatic plants can be damaged by the grazing activities of herbivorous animals. To examine the impacts of grazing damage on the release of […]

Advantages of rough wetland designs

June 1, 2016

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In natural wetlands, the unevenness of the ground creates variation in environmental factors such as soil moisture and temperature, and this variability is a positive influence on the range of plant species that are able to colonise the area. As they become established, plants such as sedges and rushes slowly create tussocks, which further increase […]

How environmentally-damaging are run-of-river hydropower systems?

June 1, 2016

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Hydropower generation typically involves the creation of large dams for the storage and release of water, which can have serious adverse effects on riverine environments. However, growing pressures on governments to meet renewable energy targets have stimulated interest in small-scale hydropower systems, especially run-of-river schemes, which use the flow within a river channel and operate […]