Association of State Wetland Managers - Protecting the Nation's Wetlands.

The Compleat Wetlander: Celebrating the First Ever National Assessment of Wetland Health

cwlogoBy Jeanne Christie

On May 11, 2016 the U.S. Environmental Protection Agency released the first ever report on the condition of the Nation’s wetlands.  Past reports from the U.S. Fish and Wildlife Service have evaluated overall changes in wetland acreage (net loss). This report is different.  It evaluates how healthy wetlands are nationwide.

This report is one of four National Aquatic Resource Surveys carried about by the U.S. Environmental Protection Agency in partnership with states and others nationwide.  cwnationalwetlands051216The other assessments cover coastlines, Lakes, and Rivers and Streams.

The good news is that nationally 48% of the wetlands are in good biological condition.  However 20% are only in fair condition and 32% are in poor condition.  It’s reasonable to anticipate that those in good condition also do a good job of providing the benefits we value – improving water quality, attenuating floodwater, supporting fish and wildlife. However, those in poor condition provide more limited benefits.

The chief problems found in wetlands that lead to poor health are compaction of soils (called ‘hardening’ in the report), vegetation removal, and ditching.   While it’s easy to understand that ditching wetlands or stripping them of vegetation would degrade a wetland, the concept that wetlands are hurt by hardening (soil compaction) is likely less familiar – at least as it relates to wetland health.  Soil compaction occurs when soil is compressed leading to smaller pore sizes in the soils and that makes it more difficult for air, water, organisms and plant roots to move through the wetland soil.  The movement of vehicles, people or livestock passing through wetlands can lead to soil compaction.  So, for example, if a wetland is ditched, the equipment used to carry out the ditching also created compaction. If livestock walk through wetlands repeatedly, overt time compaction occurs.

assessmentregions051216In addition, the report divides the nation into four major areas to provide additional analysis on the health of wetlands by region.  They are the coastal plain, eastern mountains and upper midwest, interior plains and the west.  The regional analyses provide great insight into the differences in wetland health across the country.  The report concludes that wetlands in the West are in poorer condition than other parts of the country. Specifically in the West, 21% of the wetlands were in good condition while in the rest of the country 44%-54% of the wetlands were in good condition.   To understand how the results of the report reflect these differences, it is necessary to spend a little time learning how to interpret the figures in the National Wetland Condition Assessment.

nwcaresults051216For example, report figures indicate that there was a high incidence of nonnative plants in the West when compared to other parts of the country.

stressorsepa051216In addition ditching and hardening (soil compaction) occurred more frequently.

hydrologic051216This is the first time a report like this has been conducted and it provides state and tribal wetland managers, federal agencies and others with the opportunity to review, evaluate and understand these findings and the insights they provide into how land use practices impact wetlands around the country.

These findings are by large ecoregions and are only statistically significant when applied to these large areas.  There may be additonal information available to provide greater insight into the health of wetlands at the state or tribal level.  To assist states and tribes in providing information about the results of the  National Wetland Condition Assessment and how the report relates to individual states or tribes, the Association of State Wetland Managers has provided templates for fact sheets, briefing materials, press kits, etc.  that can be adapted as needed.

The report is based on data collected in 2011 by the U.S.  Environmental Protection Agency, 45 states and tribes, 9 other federal agencies, and 28 other partners.  This is a snapshot of the nation’s wetlands at one point in time.  The U.S. Environmental Protection Agency is carrying out updates to each of the National Aquatic Resource Surveys on a rotating basis. This year, 2016, teams will be out gathering data for an updated assessment of wetland condition which will provide new information and allow for us to understand trends in the health of the nation’s wetlands over time.

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One Response to The Compleat Wetlander: Celebrating the First Ever National Assessment of Wetland Health

  1. Charles Kemp says:

    These assessments are actually pretty interesting in my opinion. I think it would be really nice to have a way to monitor the progress going on. I thought about doing vegetation assessments for a summer. It sounded like a lot of fun and you even get to work outside.

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