阳光能降低金藻毒性

A new Baylor University study has found that sunlight decreases the toxicity² of golden algae³（金藻） , which kills millions of fish in the southern United States every year. While golden algae is primarily a coastal⁴ species, it has been found in Texas rivers and lakes, including Lake Whitney and Lake Waco in Central Texas, and Lake Granbury in North Texas. Experts believe that several environmental factors influence toxin⁵ production, but new research from Baylor scientists shows that sunlight is a key component⁶ in the magnitude and duration of the toxicity of the algae to fish. Specifically, the study found that the longer golden algae toxins⁷ are exposed to natural sunlight, the less toxic¹ the algal toxin becomes to fish and other aquatic⁸（水生的） organisms.

"What we think happens in terms of the large fish kills is that sunlight only penetrates⁹ down so deep in a lake, so in a lake with golden algae blooms, fish located at greater depths may be exposed to more algal toxins," said study co-author Dr. Bryan Brooks¹⁰, associate professor of environmental sciences and biomedical studies at Baylor and director of the environmental health sciences program. "Golden algae is aggressive and very unique because it can produce its own toxins, swim, photosynthesize（光能合成） and feed on other organisms. If we can figure out what stimulates¹¹ and decreases the growth of this algae, we might be able to control it."

Along the Brazos River in north and central Texas, at least seven-million fish have been killed since 1988 due to high golden algae levels, according to Texas Parks and Wildlife. In fact, in 2005 more than a million fish died in Lake Whitney over a three-month period. Officials believe large golden algae blooms contributed to the deaths, attacking the fishes' gills and causing them to suffocate¹²（压制，受阻） .

The study appears on-line in the Journal of Plankton¹³ Research.