**5. Conclusions**

We use the NWCA as an example of how physical, chemical, and biological data collected in the field can be synthesized to evaluate the state of *wetland resource* 

**165**

**Acknowledgements**

*Wetland Assessment: Beyond the Traditional Water Quality Perspective*

answers questions of interest to the public. These might include:

• What factors are negatively affecting *aquatic resource quality*?

with those from other data collected using the NARS methodology.

across ecosystem types, spatial scales, and political entities.

• How do the patterns in *aquatic resource quality* change over time?

Moreover, the questions can be addressed using tested and established NARS methods to gather data for reporting on *aquatic resource quality* using condition, relative extent, and relative risk. NARS field, laboratory, and analysis methods are publicly available and applicable to multiple scales. NARS methodology allows for the consideration of results beyond the context of individual sampled sites, thus increasing the power of the data. For example, (a) results can be compared to regional and national NARS datasets, or (b) results can be compared or combined

The example in this chapter was national in scale and evaluated wetlands; however, sampling physical, chemical, and biological indicators to characterize condition can also be applied to regional, state, and local aquatic ecosystems. *Aquatic resource quality* is broadly relevant and supports management and policy decisions

The NWCA was planned, funded, and organized by the US Environmental Protection Agency's (USEPA) Office of Water (OW) and Office of Research and

• What is the state of the *aquatic resource quality*?

*quality* (a specific type of *aquatic resource quality*). Furthermore, we illustrate that we can evaluate the factors affecting *wetland resource quality* on a national scale

We believe that the concept of *aquatic resource quality* should be the basis for monitoring aquatic ecosystems. First, *aquatic resource quality* reflects condition, which is founded in physical, chemical, and biological data. Therefore, *aquatic resource quality* directly addresses the CWA goals for reporting on the physical, chemical, and biological integrity of water resources. Secondly, the concept of *aquatic resource quality* can be evaluated in all aquatic ecosystems, regardless of surface water availability (as in the case of precipitation-driven wetlands and ephemeral streams) or aquatic ecosystem type (e.g., wetlands versus streams). In fact, the data needed to evaluate *aquatic resource quality* in all aquatic ecosystems across the conterminous US are already being collected through the Environmental Protection Agency's (USEPA) National Aquatic Resource Surveys (NARS) program (https://www.epa.gov/national-aquatic-resource-surveys). Physical, chemical, and biological data are collected every year from one of four aquatic resources—rivers and streams, lakes, wetlands, and coasts—to assess the status of their condition. The NWCA, discussed extensively here, is the wetland component of NARS. Every 5 years, the entire water resource of the nation is assessed, allowing appraisal of trends and changes over time. In addition, because condition, relative risk, and relative extent are measured using comparable design, field protocols, and analysis methods for all aquatic resources assessed in NARS, the opportunity exists to evaluate and compare *aquatic resource quality* across ecosystem types on a national scale. Another advantage of adopting *aquatic resource quality* as the basis for monitoring aquatic ecosystems is that the results are easily translatable to a non-scientific audience, in part because the concepts and terminology are unambiguous. In addition, information surrounding *aquatic resource quality* can be reported in a way that

*DOI: http://dx.doi.org/10.5772/intechopen.92583*

using relative extent and relative risk.

*Wetland Assessment: Beyond the Traditional Water Quality Perspective DOI: http://dx.doi.org/10.5772/intechopen.92583*

*Water Quality - Science, Assessments and Policy*

indicator and good condition.

*(figure adapted from USEPA [8]).*

**Figure 6.**

impact *wetland resource quality*.

**5. Conclusions**

vegetation removal and hardening are present at high stressor levels and 1.6 times higher when vegetation replacement, damming, ditching, and filling/erosion are present at high stressor levels. A relative risk of 1.0 indicates that there is no association or relationship between the indicator of stress and condition, and a relative risk less than 1.0, indicates a positive relationship between high stressor level of the

*Evaluation of the factors that affect wetland resource quality as indicated by relative extent (percent area of the wetland resource) and relative risk from chemical, physical, and biological indicators of stress for the 2011 National Wetland Condition Assessment (NWCA). NA indicates "not applicable" for relative risk of the nonnative plan indicator to avoid circularity (see text for details). Error bars are 95% confidence intervals* 

The results of the 2011 NWCA indicates that the *wetland resource quality* across the conterminous US is good for about half of the wetland area, with the remainder divided between fair and poor *wetland resource quality* (**Figure 5**). Physical, chemical, and biological data collected in the field can also be used to evaluate factors that impact wetland resource quality. Review of the patterns in relative extent of the examined indicators of stress that were found at high stressor level, shows that specific physical stressors and the biological stressor were the most frequently encountered and may affect wetland resource quality, while chemical indicators of stress are less common at high stressor levels (**Figure 6**). The effect of stressors on *wetland resource quality* is illustrated by the relative risk results (**Figure 6**), which show that physical indicators of stress occurring at high stressor levels are likely to

We use the NWCA as an example of how physical, chemical, and biological data

collected in the field can be synthesized to evaluate the state of *wetland resource* 

**4.3 Summary of** *wetland resource quality* **in the conterminous US**

**164**

*quality* (a specific type of *aquatic resource quality*). Furthermore, we illustrate that we can evaluate the factors affecting *wetland resource quality* on a national scale using relative extent and relative risk.

We believe that the concept of *aquatic resource quality* should be the basis for monitoring aquatic ecosystems. First, *aquatic resource quality* reflects condition, which is founded in physical, chemical, and biological data. Therefore, *aquatic resource quality* directly addresses the CWA goals for reporting on the physical, chemical, and biological integrity of water resources. Secondly, the concept of *aquatic resource quality* can be evaluated in all aquatic ecosystems, regardless of surface water availability (as in the case of precipitation-driven wetlands and ephemeral streams) or aquatic ecosystem type (e.g., wetlands versus streams). In fact, the data needed to evaluate *aquatic resource quality* in all aquatic ecosystems across the conterminous US are already being collected through the Environmental Protection Agency's (USEPA) National Aquatic Resource Surveys (NARS) program (https://www.epa.gov/national-aquatic-resource-surveys). Physical, chemical, and biological data are collected every year from one of four aquatic resources—rivers and streams, lakes, wetlands, and coasts—to assess the status of their condition. The NWCA, discussed extensively here, is the wetland component of NARS. Every 5 years, the entire water resource of the nation is assessed, allowing appraisal of trends and changes over time. In addition, because condition, relative risk, and relative extent are measured using comparable design, field protocols, and analysis methods for all aquatic resources assessed in NARS, the opportunity exists to evaluate and compare *aquatic resource quality* across ecosystem types on a national scale.

Another advantage of adopting *aquatic resource quality* as the basis for monitoring aquatic ecosystems is that the results are easily translatable to a non-scientific audience, in part because the concepts and terminology are unambiguous. In addition, information surrounding *aquatic resource quality* can be reported in a way that answers questions of interest to the public. These might include:


Moreover, the questions can be addressed using tested and established NARS methods to gather data for reporting on *aquatic resource quality* using condition, relative extent, and relative risk. NARS field, laboratory, and analysis methods are publicly available and applicable to multiple scales. NARS methodology allows for the consideration of results beyond the context of individual sampled sites, thus increasing the power of the data. For example, (a) results can be compared to regional and national NARS datasets, or (b) results can be compared or combined with those from other data collected using the NARS methodology.

The example in this chapter was national in scale and evaluated wetlands; however, sampling physical, chemical, and biological indicators to characterize condition can also be applied to regional, state, and local aquatic ecosystems. *Aquatic resource quality* is broadly relevant and supports management and policy decisions across ecosystem types, spatial scales, and political entities.

### **Acknowledgements**

The NWCA was planned, funded, and organized by the US Environmental Protection Agency's (USEPA) Office of Water (OW) and Office of Research and Development (ORD), and implemented by numerous state, federal, and contractor field crews, information management staff, and laboratory staff whose efforts the authors gratefully acknowledge. The authors appreciate the thoughtful reviews provided by Alan Herlihy, Oregon State University, Gregg Serenbetz, USEPA OW, and James Markwiese, USEPA ORD. Their input greatly improved the manuscript.

This chapter has been subjected to the USEPA's review process and has been approved for publication. The views expressed in this chapter are those of the authors and do not necessarily reflect the views or policies of the agency. Any mention of trade names, products, or services does not imply an endorsement by the US Government or the USEPA. The USEPA does not endorse any commercial products, services, or enterprises. This work was authored by US Government employees as part of their official duties. In view of Section 105 of the Copyright Act (17 U.S.C. §105), this chapter is not subject to US copyright protection.
