Tag: Eutrophication

Environment: Excess nutrients speed up ocean acidification

Shellfish are expected to be hit hard by ocean acidification in the coming decades. Bob Berwyn photo.

CO2 from decaying algae blooms adds to ocean woes

By Summit Voice

SUMMIT COUNTY — Runoff from agricultural and urban areas is speeding up ocean acidification in some coastal areas, adding to the woes resulting from increased concentration of atmospheric carbon dioxide.

A new study by researchers with the National Oceanic and Atmospheric Administration and the University of Georgia found that CO2 released from decaying algal blooms intensifies acidification, which is already taking a toll on shellfish populations in some areas.

Ocean acidification occurs when the ocean absorbs carbon dioxide from the atmosphere or from the breakdown of organic matter, causing a chemical reaction to make it more acidic. Species as diverse as scallops and corals are vulnerable to ocean acidification, which can affect the growth of their shells and skeletons. Continue reading “Environment: Excess nutrients speed up ocean acidification”


Earth’s nitrogen cycle profoundly affected by humans

Nitrogen pollution affects wide range of land, sea ecosystems

Even high mountain lakes are feeling the sting of nitrogen pollution.

By Summit Voice

SUMMIT COUNTY — Nitrogen pollution is becoming one of the most pervasive global environmental problems, with nutrient pollution from agricultural runoff and sewage leading to coral diseases, bird die-offs, fish diseases, human diarrheal diseases and vector-borne infections transmitted by insects such as mosquitos and ticks.

About two-thirds of U.S. coastal systems are moderately to severely impaired due to nutrient loading and there are now nearly 300 hypoxic (low oxygen) zones along the U.S. coastline.

Air pollution continues to reduce biodiversity, with exotic, invasive species dominating native species that are sensitive to excess reactive nitrogen. For example, in California, airborne nitrogen is impacting one third of the state’s natural land areas,  and the expansion of nitrogen-loving, non-native, highly flammable grasses in the western U.S. has increased fire risk in the region.

These conclusions are part of a sobering assessment by a multi-disciplinary team of scientists led by Eric Davidson of the Woods Hole Research Center who reviewed the major sources of reactive nitrogen in the U.S., resulting effects on health and the environment, and potential solutions. Continue reading “Earth’s nitrogen cycle profoundly affected by humans”