Encyclopedia of Earth
Encyclopedia of Earth: Biogeochemistry: Phosphorus Cycle
Article explaining what the phosphorus cycle is, where it occurs, its place in the biotic world, and the environmental impact of human activities on the phosphorus cycle. (Published: October 8, 2009)
CK-12 Foundation
Ck 12: Earth Science: Flow of Matter in Ecosystems
[Free Registration/Login may be required to access all resource tools.] In this module, students will learn about the cycles of nature (water, carbon, nitrogen, and phosphorus) that support the flow of nutrient matter through an...
Georgia Department of Education
Ga Virtual Learning: Ap Environmental Science: Science, Matter, Energy, Systems
Through interactive activities, reading exercises, and lab activities, students study how science, matter, energy, and systems are interrelated.
Other
Water on the Web
Water on the Web (WOW) is an advanced site allowing students to actively participate in data analysis from real research sites. Lesson plans on a range of topics are provided. There is also a tutorial for using Excel to graph WOW data.