Welcome to the Science Topics page of the USGS Water Science School, where you can explore the many aspects of water. All of our science information is available by browsing the Themes below.
Science Topics
FAQs
What are wetlands?
Wetlands are transitional areas, sandwiched between permanently flooded deepwater environments and well-drained uplands, where the water table is usually at or near the surface or the land is covered by shallow water. They include mangroves, marshes (salt, brackish, intermediate, and fresh), swamps, forested wetlands, bogs, wet prairies, prairie potholes, and vernal pools. In general terms...
Why are wetlands important?
Wetlands provide habitat for thousands of species of aquatic and terrestrial plants and animals. Wetlands are valuable for flood protection, water quality improvement, shoreline erosion control, natural products, recreation, and aesthetics. Wetlands are among the most productive habitats on earth providing shelter and nursery areas for commercially and recreationally important animals like fish...
What are the differences between endangered, threatened, imperiled, and at-risk species?
Under the Endangered Species Act (ESA), plant and animal species may be listed as either endangered or threatened. “Endangered” means a species is in danger of extinction throughout all or a significant portion of its range. “Threatened” means a species is likely to become endangered within the foreseeable future. States have their own ESA-type laws, so species can have different Threatened...
Education
Teacher's Resources for Water Education
The USGS Water Science School offers many resources to teachers help teach students all about water.
Water Science Activity Center
This is the interactive section of our site where you can answer challenge questions, participate in opinion surveys about water issues, and take true/false quizzes.
Principal Aquifers
An aquifer is a geologic formation, a group of formations, or a part of a formation that contains sufficient saturated permeable material to yield significant quantities of water to wells and springs. This site explains the geology of aquifers and provides a general overview and maps of the principal aquifers of the United states.