2006 Greater Everglades Ecosystem Restoration Conference

A New Analysis Approach for Characterizing Canal Water Penetration into Wetlands - A Case Study of the A.R.M. Loxahatchee National Wildlife Refuge

Donatto Surratt, Mike Waldon and Matthew Harwell

A.R.M. Loxahatchee National Wildlife Refuge, Boynton Beach, FL, USA

There are a variety of ways to analyze spatial water quality data. Approaches for analyzing water quality data along transects include typical gradient analyses and generation of isopleths. As presented elsewhere at the 2006 GEER conference, these types of approaches were used to characterize penetration of canal water into the interior of the A.R.M. Loxahatchee National Wildlife Refuge (Refuge). One limitation of these approaches is that any explicit connection between structure operations and water quality conditions in the interior marsh remains challenging to characterize. Therefore, a novel approach for spatial water quality analysis has been developed and applied to the Refuge, working with the same structure flow data and marsh conductivity data as part of the Refuge’s Enhanced Water Quality Monitoring and Modeling Program (http://www.sofia.usgs.gov/lox_monitor_model).
This approach characterized simultaneous patterns of marsh penetration by canal water from the L-40 (eastern perimeter canal), the L-7 (northwestern perimeter canal), and the L-39 (southwester perimeter canal). Refuge bulk water supply (not including rainfall) enters through northern structures and exists through southern structures. Structure releases influence canal water movement, but the relationship to water movement in the marsh needs to be elucidated. Here, we examined snapshots of conductivity over time across two spatial dimensions: 1) site distance from the nearest point on the nearest canal and 2) site distance clock-wise from the northeastern most bypass structure (G300). To characterize canal water intrusion into the marsh interior with respect to structure operations, conductivity data were examined from April to July 2005. The approach is suggested by the working hypothesis that the major spatial parameter affecting water quality constituents is distance from the canal, rather than specific site coordinates.
This type of analysis approach can provide additional insight into how water management actions in one region of the Refuge may influence the interior marsh. When coupled with other hydrodynamic and water quality modeling tools, scientist will be able to enhance the overall understanding of the Refuge to answer management questions.

Contact Information: Donatto Surratt, A.R.M. Loxahatchee NWR, 10216 Lee Road, Boynton Beach, FL, 33437 USA, Phone: 561-735-6003, Fax: 561-735-6008, Email: donatto_surratt@fws.gov