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Study investigates extraordinary trout with tolerance to heavily polluted water

By Guest PostAugust 1, 2013Environmentaccumulation of metals, aquatic ecosystems, brown trout, concentrations of metals, cornwall, eduarda santos, Environment, extraordinary trout, gene encoding, genetic diversity, heavily polluted water, history, human activities, kidney, liver, metal content, metallothionein, mining activity, n bury, nerc, protein, river hayle, signs of toxicity, university of exeter, unpolluted sites, uren webster

New research from the University of Exeter and King’s College London has shown how a population of brown trout can survive in the contaminated waters of the River Hayle in Cornwall where metal concentrations are so high they would be lethal to fish from unpolluted sites.

The team believe this is due to changes in the expression of their genes. The research was funded by NERC and the Salmon and Trout Association.

The researchers compared the trout living in the River Hayle with a population living in a relatively clean site in the River Teign. The results showed that the accumulation of metals in the kidney and liver – where metals are stored and detoxified – were 19 and 34 times higher in the Hayle trout, respectively. In the gill, concentrations averaging 63 times higher were present in the Hayle fish, but there were no differences in metal content in the gut. This accumulation of metals in the Hayle fish highlights their extraordinary tolerance of the extreme metal concentrations in their environment. (more…)

Acid Rain Study Show Substantial Decreases, But More Progress is Needed

By Guest PostJanuary 21, 2012Environmentacid rain, acid sensitive, acidic compounds, acidification, adirondack mountains, air quality, american science, aquatic ecosystems, atmosphere, clean air act amendments, climate change, coal, coastal ecosystems, doug burns, emission reductions, emissions, environmental damage, fine particles, forest fires, fossil fuel, gas, human health, hydrologist, john p holdren, lakes, multiple pollutants, new york, nitrogen oxides, oil, oxidants, ozone concentration, population, power plants, streams, sulfur dioxide, U.S. Geological Survey, visibility, water quality

WASHINGTON, D.C. — Measurable improvements in air quality and visibility, human health, and water quality in many acid-sensitive lakes and streams, have been achieved through emissions reductions from electric generating power plants and resulting decreases in acid rain. These are some of the key findings in a report to Congress by the National Acid Precipitation Assessment Program, a cooperative federal program.

The report shows that since the establishment of the Acid Rain Program, under Title IV of the 1990 Clean Air Act Amendments, there have been substantial reductions in sulfur dioxide (SO₂) and nitrogen oxides (NO_x) emissions from power plants that use fossil fuels like coal, gas and oil, which are known to be the primary causes of acid rain. As of 2009, emissions of SO₂ and NO_x declined by about two-thirds relative to levels in the 1990s. These emissions levels declined even further in 2010, according to recent data compiled by the U.S. Environmental Protection Agency. (more…)

Upper Atmosphere Facilitates Changes That Let Mercury Enter Food Chain

By Guest PostJanuary 5, 2012Environmentaquatic ecosystems, atmosphere, bacteria, bangor, broomfield, chemical reactor, climate conditions, coal burning in asia, daniel jaffe, ecosystem impacts, Europe, food chain, humans, lower stratosphere, maine, mercury, mercury contaminated fish, mercury emissions, metallic element, methyl mercury, North America, oxidation, oxidized mercury, research aircraft, seth lyman, southwest united states, university of washington bothell, upper atmosphere, upper troposphere, vapor

Humans pump thousands of tons of vapor from the metallic element mercury into the atmosphere each year, and it can remain suspended for long periods before being changed into a form that is easily removed from the atmosphere.

New research shows that the upper troposphere and lower stratosphere work to transform elemental mercury into oxidized mercury, which can easily be deposited into aquatic ecosystems and ultimately enter the food chain. (more…)

Tag Archives: aquatic ecosystems

Study investigates extraordinary trout with tolerance to heavily polluted water

Acid Rain Study Show Substantial Decreases, But More Progress is Needed

Upper Atmosphere Facilitates Changes That Let Mercury Enter Food Chain