Abstract
Tools for assessing and communicating salt marsh condition are essential to guide decisions aimed at maintaining or restoring ecosystem integrity and services. Multimetric indices (MMIs) are increasingly used to provide integrated assessments of ecosystem condition. We employed a theory-based approach that considers the multivariate relationship of metrics with human disturbance to construct a salt marsh MMI for five National Parks in the northeastern USA. We quantified the degree of human disturbance for each marsh using the first principal component score from a principal components analysis of physical, chemical, and land use stressors. We then applied a metric selection algorithm to different combinations of about 45 vegetation and nekton metrics (e.g., species abundance, species richness, and ecological and functional classifications) derived from multi-year monitoring data. While MMIs derived from nekton or vegetation metrics alone were strongly correlated with human disturbance (r values from −0.80 to −0.93), an MMI derived from both vegetation and nekton metrics yielded an exceptionally strong correlation with disturbance (r = −0.96). Individual MMIs included from one to five metrics. The metric-assembly algorithm yielded parsimonious MMIs that exhibit the greatest possible correlations with disturbance in a way that is objective, efficient, and reproducible.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 334-348 |
| Number of pages | 15 |
| Journal | Estuaries and Coasts |
| Volume | 41 |
| Issue number | 2 |
| DOIs | |
| State | Published - Mar 1 2018 |
| Externally published | Yes |
Bibliographical note
Funding Information:This work was supported, in part, by funding from USGS National Park Monitoring Program. In addition, GRG and JGB acknowledge support from the USGS Climate and Land-Use Research and Development Program. We are grateful to Holly Plaisted for assistance with data preparation, to Jennifer Olker for analytical guidance, and to the many NPS professional staff and summer research assistants who helped with vegetation and nekton sampling. We extend sincere appreciation to Nick Danz and two anonymous reviewers for helpful comments that improved the manuscript. All data used in this paper are publicly available through USGS at 10.5066/F7ZP449D. The use of trade, product, or firm names in this publication is for descriptive purposes only and does not imply endorsement by the US Government.
Funding Information:
Acknowledgements This work was supported, in part, by funding from USGS National Park Monitoring Program. In addition, GRG and JGB acknowledge support from the USGS Climate and Land-Use Research and Development Program. We are grateful to Holly Plaisted for assistance with data preparation, to Jennifer Olker for analytical guidance, and to the many NPS professional staff and summer research assistants who helped with vegetation and nekton sampling. We extend sincere appreciation to Nick Danz and two anonymous reviewers for helpful comments that improved the manuscript. All data used in this paper are publicly available through USGS at https://dx.doi.org/10. 5066/F7ZP449D. The use of trade, product, or firm names in this publication is for descriptive purposes only and does not imply endorsement by the US Government.
Publisher Copyright:
© 2017, Coastal and Estuarine Research Federation (outside the USA).
Keywords
- Coastal wetlands
- Ecological indicators
- Ecosystem assessment
- Multimetric index
- Salt marsh
