The Nitrogen Cycle: Of Microbes and Men
Human Alteration of the Global Nitrogen Cycle
Ecological Society of America - An overview of the scientific understanding of human-induced changes to the global nitrogen cycle and the consequences.
Illinois State Water Survey - More detailed information about how nitrogen passes through the atmosphere, biosphere, geosphere, and hydrosphere.
World Bank - a visual representation of the World Bank's nitrous oxide emissions dataset
News & Events
Algal Blooms and Eutrophication
Department of Ecology, State of Washington
Airplane exhaust may affect earth's climate
Science News Online
News from around the world of science.
Google - Research database allows searching of the scholarly literature.
State of Victoria (Australia) - this animation provides a simple illustration of the nitrogen cycle in an agricultural context.
Air Emission Sources - Nitrogen Oxides
Environmental Protection Agency (EPA) - a national database of air emissions information, including nitrogen oxides (NOx) emissions by source. View information on air quality standards, trends, health effects, and programs to reduce NOx.
Next Generation Science Standards (NGSS)
Next Generation Science Standards: For States, By States
National Academies Press: A Framework for K-12 Science Education