National Park Service

Northeast Temperate Network (NETN)

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A wetland is an area of land that has soil that is saturated with moisture either permanently or seasonally. They can exist in areas as diverse as tundra to tropics and can be found on every continent except Antarctica. Such areas may also be covered partially or completely by shallow pools of water. Wetlands vary widely because of regional and local differences in soils, topography, climate, hydrology, water chemistry, vegetation, and other factors, including human disturbance. Wetlands include swamps, marshes, and bogs, among others. The water can be saltwater, freshwater, or brackish. The world's largest wetland is the Pantanal which straddles Brazil, Bolivia and Paraguay in South America. Wetlands are considered the most biologically diverse of all ecosystems. Plant life found in wetlands includes mangrove, water lilies, cattails, sedges, tamarack, black spruce, cypress, gum, and many others. Animal life includes many different amphibians, reptiles, birds, and mammals.The study of wetlands has recently been termed paludology in some publications.

Importance & Issues

Installing a sand filter pack around a wetland monitoring well.Wetlands are important sites of biodiversity, and half of all endangered species are found in marshes, swamps, bogs, and fens. Wetlands serve many important ecological functions, including groundwater recharge, habitat for flora and fauna, soil erosion control, chemical uptake and transformation, and flood water control. Wetlands of the NETN are threatened by a suite of anthropogenic stresses associated with increasing visitor pressure and rapid residential development of watersheds adjacent to the parks. A monitoring program is essential to help resource managers document trends in wetland condition, evaluate potential threats, and identify areas of management concern. This protocol will identify robust indicators of wetland function that are suitable for monitoring the condition of the NETN predominant wetland types (freshwater emergent wetlands, forested and scrub/shrub wetlands, peatlands, and salt marshes), and determine the sample size necessary to detect change in these variables through routine monitoring. The protocol will also identify landscape attributes that can be used to assess the susceptibility of park wetlands to anthropogenic stressors as a basis for a stratifed sampling design.

Monitoring Objectives

The overall goal is to monitor status and trends in permanent freshwater wetland vegetation, hydrology, and water quality in Acadia NP. Specific monitoring objectives include:

  • Determine the status and trends in vegetation structure, including changes in herbaceous, shrub, and tree cover, using sentinel sites.
  • Determine status and trends in vascular plant species composition, diversity, and abundance using sentinel sites. Special emphasis will be on species of high conservation priority (i.e., vulnerable [S3], imperiled [S2] or critically imperiled [S1] in the state), indicators of wetland condition, and invasive species.
  • Determine the status and trends in water chemistry, including pH, conductance, and nutrients, using sentinel sites.
  • Determine baseline conditions in soil chemistry, including pH, conductance, and nutrients, using sentinel sites.
  • Determine the status and trends of water level, including variability and seasonal patterns of water depth, using shallow wells installed in sentinel sites.
  • Determine the status and trends in indicators of wetland condition and stressors, including adjacent land-use, condition of buffer, abundance of invasive species, and hydrologic disturbance, using rapid assessments (Level 1 and 2) of randomly selected wetlands.



Last Updated: December 30, 2016 Contact Webmaster