Browsing All Posts filed under »connectivity«

What drives regional differences in streamflow?

October 8, 2018

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Typically, large-scale models of stream flow take into account the interaction between climate and vegetation (which determines evapotranspiration) and landscape features that dictate how non-evaporated water is diverted to soil, groundwater and overland flow.  However, there are often strong spatial variations in streamflow drivers, which can limit the usefulness of global models.  Researchers drew on […]

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 […]

Lakes are good for river species

October 8, 2018

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While it’s known that terrestrial landscape features, such as soil type, topography and land use, influence the abundance and distribution of stream fish, only a few studies have considered the possible effects of lakes on stream fish populations.  Biologists carried out a three-year study on native brook trout (Salvelinus fontinalis) in 36 streams in the […]

Why are there so many crocodiles in tropical waterholes?

March 26, 2018

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Transfers of organic material from one aquatic environment to another (for example, through flood pulses or animal migrations) allow productive donor ecosystems to subsidise less productive habitats. However, there are big variations in the extent to which different animal species depend on production subsidies.  To explore such differences, Australian researchers collected a wide array of […]

Aquatic plants help animal plankton to disperse

March 25, 2018

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Freshwater bodies containing aquatic plants generally support a wide range of animal plankton. If the dormant stages of zooplankton are attached to roots and the submerged parts of plants, the dislodgement and displacement of aquatic vegetation during floods could play a role in plankton dispersal. To assess this possibility, Argentinian researchers collected specimens of free-floating […]

Restoration and invertebrates: Build it and at least some of them will come

September 25, 2017

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It’s commonly assumed that the biodiversity of a disturbed ecosystem can be improved by restoring its original physical and chemical conditions. According to this “Field of Dreams” view (“build it and they will come”), ecosystem recovery occurs through the recolonization activities of lost species.  While a lot of river restoration is founded on Field of […]

Human impacts on ecological connectivity

June 19, 2017

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Ecological connectivity – the exchange of organisms between habitat patches or subpopulations – has an influence on many key processes, including population dynamics, nutrient flux, disease transmission, species invasions, food-web interactions, genetic isolation and the maintenance of biodiversity. A recent study reviewed ways in which graph theory has been used to investigate how human activities […]