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, wetlands are lands where saturation with water is the dominant factor determining the nature of soil development and the types of plant and animal communities living in the soil and on its surface. The single feature that most wetlands share is soil or substrate that is at least periodically saturated with or covered by water.
Learn more: USGS Wetland and Aquatic Research Center
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What are the long-term effects of climate change?
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Why are wetlands important?
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Changes in Rainfall, Temperature Expected to Transform Coastal Wetlands This Century
Changes in rainfall and temperature are predicted to transform wetlands in the Gulf of Mexico and around the world within the century, a new study from the USGS and the University of Texas Rio Grande Valley concludes.
New Technique Quickly Predicts Salt Marsh Vulnerability
If coastal salt marshes are like savings accounts, with sediment as the principal, all eight Atlantic and Pacific coast salt marshes studied are "in the red," researchers found.
Normal Weather Drives Salt Marsh Erosion
For salt marshes, hurricanes are just another day at the beach.
Drainage of Prairie Pothole Wetlands Can Increase Flooding and Degrade Ecosystems
The drainage of small wetlands can decrease wildlife habitat and may contribute to flooding in the Prairie Pothole Region (PPR), according to a recent U.S. Geological Survey study.
Connectivity Best for Created Wetlands
New research by the U.S. Geological Survey has found that many wetlands created for habitat do very little to improve water quality problems in streams and rivers. Collectively, these wetland design practices represent a missed opportunity to improve the general ecological health of watersheds and wetland ecosystems.
Rising Seas Could Threaten Many Acadia NP Marshes
More than 800 acres of uplands in and near Acadia National Park will likely be flooded by the ocean if sea level rises 2 feet during this century, leaving 75 percent of the saltwater marshes along this part of central Maine's rugged coast with very little upland area to migrate into, according to a new U.S. Geological Survey study and maps.
Climate Change May Affect the Carbon Balance of a Rocky Mountain Wetland
BOSTON--The carbon balance of wetlands in the southern Rocky Mountains may be very sensitive to small changes in local climate, according to recent research conducted by the U.S. Geological Survey.
WERC sunset over salt marsh wetland
Sunset over salt marsh wetland
High stakes, big questions in marsh grass die-back
Brown patches and brown stems show stress in this phagmites (roseau cane) stand in Pass A Loutre Wildlife Management Area, a tract of state-owned land in Louisiana's bird foot delta, where the Mississippi River meets the Gulf of Mexico. An ongoing phragmites was first discovered in spring 2017 and blamed on an invasive scale insect from Asia. But a new USGS report, based
...WERC Employee Measuring Marsh Accretion
A photo of former USGS employee (current U.S. Fish and Wildlife Service employee) Kat Powelson measuring accretion in a southern California wetland.
Nutria in Louisiana wetlands
Nutria in Louisiana wetlands
Mercury and Rice in the California Delta: Lessons Linking Wetlands to Water to Wildlife
- Wetlands are hotspots for mercury methylation and export of methylmercury to aquatic foodwebs.
- Rice is the most abundant wetland type in California and globally in temperate and tropical latitudes.
- Physical, chemical and biological Hg transformations are temporally pulsed in agricultural wetlands, due largely to seasonal water management practices.
Wetland Marsh Restored
Wetland restoration, weland restored
PubTalk 5/2012 — Restoring the Wild Heart of South San Francisco Bay
--The South Bay Salt Pond Restoration Project
By Laura Valoppi, Lead Scientist
- This is largest Western U.S. coastal wetlands restoration project, encompassing 15,100 acres of former salt ponds around the edge of South San Francisco Bay
- The project will restore and enhance South Bay wetlands for endangered