Browsing All Posts filed under »pollution«

Aquatic plants neutralize insecticides

January 14, 2019

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sThere’s increasing evidence that submerged aquatic plants can dramatically reduce concentrations of polluting insecticides in freshwater systems and thus mitigate the impacts of these chemicals on aquatic animals.  They are thought to do this in at least two ways.  The best known method is by binding hydrophobic pesticides onto and into plant tissues, and a […]

Recognising the biodiversity value of ponds

January 14, 2019

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Although pond habitats have been relatively neglected by conservationists, several studies have shown that ponds can contribute more to regional biodiversity than running waters.  Because they are isolated, small in size and often poorly protected by conservation programmes, pond ecosystems are highly vulnerable to environmental threats such as those presented by urbanisation.  To help provide […]

Rivers are hotspots for microplastics

January 14, 2019

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Microplastics (plastic particles less than 5 mm in size) derived from clothes fibres, cosmetics and the breakdown of larger plastic objects, are known to have harmful effects on organisms that ingest them in freshwater and marine environments. However, information on the transport of microplastics, especially nanoparticles (1 nm = 1x 10-6 mm) is scanty.  Dutch […]

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 […]

Worms, midges and the greenhouse effect

July 5, 2018

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Severely impacted aquatic environments such as urban wetlands and wastewater treatment ponds are designed to treat large amounts of carbon and nitrogen, which raises concerns about their potential greenhouse gas emissions.  Because pollution-tolerant worms (oligochaetes) and insects (midges) can reach very high densities in such systems, it’s possible that their activities influence  the flux of […]

Triggers for algal blooms: peak temperatures aren’t always important

July 5, 2018

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There are concerns that human impacts  on freshwater systems – particularly temperature increases linked to climate change and nutrient enrichment caused by run-off and pollution – are encouraging the spread of blue-green algae (cyanobacteria) capable of generating toxic blooms that threaten human and animal health.  One such case is the recent spread of Cylindrospermopsis raciborskii, […]

Ironing out harmful algal blooms

September 25, 2017

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An understanding of how iron affects the supply of nutrients in aquatic systems may open the door to better success in managing harmful algal blooms. In highly productive lakes, the release of phosphorus stored in the bottom sediment can encourage bloom development, but nutrient release is retarded in the presence of iron, which precipitates phosphorus […]