the rise of slime
The Consequences of Overfeeding our Oceans By Mary M. Cerullo and R. Michael Doan, Friends of Casco Bay
Nutrient pollution spurs the growth of algae.
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Waterkeeper Magazine Fall 2007
changing the very ecology of our oceans. We pump so much nitrogen into the ocean that the diverse array of microscopic plants that form the base of the food web are being replaced by nitrogen-devouring blue-green algae. And when life at the bottom of the food chain experiences such a dramatic shift, the entire system changes, all the way up to animals we like to eat, like scallops, clams, lobsters and fish. The constant deposition of nitrogen to our oceans is changing the fundamental structure of our marine ecosystem in ways we can’t predict, but are apt not to like. Nitrogen is everywhere. It makes up 78 percent of the air we breathe and it is an essential nutrient that stimulates the growth of terrestrial plants. Healthy amounts of nitrogen are needed to jumpstart the growth of tiny plants that form the base of the ocean food chain, which nurture fish, clams, oysters, crabs, lobsters and whales. Rivers wash melting snow and rain, and the nutrients they carry, into our waters in a natural process that provides the ocean food web with a balanced diet, an alphabet soup of nutrients. Plants bloom, animals eat the plants and smaller animals are eaten by bigger animals. When all these organisms die, they are broken down by bacteria, recycling the nutrients to support the growth of new marine life. But an overdose of nitrogen has tilted the cycle of life dangerously off balance. This overdose is killing the ocean as we know it. Two recent assessments of the health of the coastal oceans by the U.S. Commission on Ocean Policy and the Pew Oceans
© Kike Calvo/Alamy
Too much of a good thing.
Casco Baykeeper
»Nitrogen pollution is on an insidious rise and is
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