It's About Time
The Nitrogen and Phosphorous Cycles
How do we affect the ecosystem, and what can we do to preserve it? Pupils explore chemicals that promote and inhibit plant growth, then discuss the importance of nitrogen and phosphorus to the survival of organisms and describe how...
National Institute of Open Schooling
Air Pollution
Seventy percent of the air pollution in China is due to car exhaust. Under the umbrella of environmental chemistry, learners extensively explore air pollution. From the makeup of our atmosphere to sources of major air pollutants, classes...
Wilderness Classroom
Pollution
Educate scholars on pollution—air, water, and land—with a series of lessons that begin with a thorough explanation of each type. Learners then take part in three activities to reinforce the importance of reducing pollution. They...
Nature Research
Nature: The Nitrogen Cycle: Processes, Players, and Human Impact
Find out how nitrogen is cycled throughout the biosphere as it passes through the nitrogen cycle. Learn about the biotic and abiotic factors involved in the process as well as the implications of human activity on the nitrogen cycle.
Other
Algone: The Nitrogen Cycle
This resource gives a brief overview of the nitrogen cycle, dealing especially with the nitrogen cycle in aquariums.
Encyclopedia of Earth
Encyclopedia of Earth: Biochemistry: Nitrogen Cycle
Article explaining what the nitrogen cycle is, and its role in an ecosystem. (Published: June 28, 2010)
University of Illinois
University of Illinois: Illinois State Water Survey: Nitrogen Cycle: Human Impact on the Nitrogen Cycle
An overview of the impact of human activities on the environment and how those actions effect the nitrogen cycle.
University of Illinois
University of Illinois: Illinois State Water Survey: Simplified Nitrogen Cycle
A semi-technical description of the nitrogen cycle. Contains a link to an abridged version of the page along with a list of further resources on the topic.
BiologyWise
Biology Wise: Nitrogen Cycle Steps
Nitrogen is essential to all living things. This article explains what the nitrogen cycle is and the five steps involved in it.
CK-12 Foundation
Ck 12: Earth Science: Nitrogen Cycle in Ecosystems Study Guide
Review the main concepts of the nitrogen cycle in this study guide.
BiologyWise
Biology Wise: Understanding Nitrogen Cycle With a Diagram
Describes the steps involved in the nitrogen cycle, a critical biogeochemical cycle.
Encyclopedia of Earth
Encyclopedia of Earth: Nitrogen
Information about the element, Nitrogen, atomic number 14. Covers common chemical transformations, its physical properties, atomic properties, how abundant it is on the Earth, and details about health-related regulations. Also discusses...
National Earth Science Teachers Association
Windows to the Universe: Biogeochemical Cycles
Biogeochemical cycles happen when individual elements are recycled over and over in different parts of the Earth. Two examples are the Nitrogen Cycle and Carbon Cycle. Read an explanation of biogeochemical cycles and view a diagram of...
BiologyWise
Biology Wise: Information About Nitrifying and Denitrifying Bacteria
Learn about the important role that nitrifying and denitrifying bacteria play in the nitrogen cycle.
Science Struck
Science Struck: Nitrogen in the Atmosphere
Learn about the properties of nitrogen, how it was first formed, where it is found, and the importance of the nitrogen cycle.
National Earth Science Teachers Association
Windows to the Universe: Ammonia Nh3
Read about the chemical compound ammonia and learn how it is part of the Nitrogen Cycle.
eSchool Today
E School Today: What Is an Ecosystem?
Learn about all the different levels of ecosystems, from the living things under a rock, up to a rainforest biome. Explains the levels of organization within an ecosystem, the different types of biomes, food chains and trophic levels,...
Other
University of Delaware: Chemosynthesis.
An explanation of how in the deep sea, where the sun's rays never reach, organisms make food from chemicals, a process called chemosynthesis.
CK-12 Foundation
Ck 12: Biology: Recycling Matter Study Guide
Review some of the cycles that recycle matter through Earth's biospheres.
Ohio State University
Ohio State University: Concepts of Plant Ecology
An advanced discussion of plant interactions and relationships. Energy flow, nutrient cycling and succession are discussed. Try the quiz to check your understanding.