Nutrient pollution

Nutrient pollution is caused by excess nitrogen and phosphorus in the air and water. Nitrogen and phosphorus are nutrients that are natural parts of aquatic ecosystems. Nitrogen is also the most abundant element in the air we breathe. Nitrogen and phosphorus support the growth of algae and aquatic plants, which provide food and habitat for fish, shellfish and smaller organisms that live in water. But when too much nitrogen and phosphorus enter the environment - usually from a wide range of human activities - the air and water can become polluted. Nutrient pollution has impacted many streams, rivers, lakes, bays and coastal waters for the past several decades, resulting in serious environmental and human health issues, and impacting the economy.

-- Source: U.S. Environmental Protection Agency

Overview

Complex physical processes such as hydrology, nutrient cycling, and sediment transport are linked to water circulation patterns in Puget Sound. 

Puget Sound. Photo: S.N. Johnson-Roehr (CC BY-NC 2.0) https://www.flickr.com/photos/snjr22/4095840433

Related Articles

Decaying organic matter plays an important role in marine ecosystems. 

This study compared recent and historical data to determine the presence of any significant changes in nutrient and oxygen concentrations subsequent to METRO discharge, examined seasonal cycles in water properties, and examined the flux of nutrients within the study area.

Hypoxia, defined as dissolved oxygen (DO) concentrations less than 2 mg / L, has become widespread throughout estuaries and semi-enclosed seas throughout the world (Diaz 2001). 

An independent review conducted by the Puget Sound Institute (PSI) is featured in findings by the Environmental Protection Agency and the Washington State Department of Ecology that there is currently “no compelling evidence” that humans are the cause for recent trends in declines in dissolved oxygen in Hood Canal.