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1. Rod surface elevation table - marker horizon (RSET-MH) in both shallow and deep configurations. All installations associated with the current work will be deep. 

1. Rod surface elevation table - marker horizon (RSET-MH) in both shallow and deep configurations. All installations associated with the current work will be deep. 

Context in source publication

Context 1
... SLR, thus informing conservation, mitigation and adaptation. The USGS is establishing a network of coastal marsh monitoring sites in the Pacific Northwest and California during 2012 and 2013 to assess the vulnerability of these coastal wetlands to changes in sea level rise (G. Guntenspergen, personal communication). Rod surface elevation table marker-horizon method (RSET and SET-MH) is the method used (see The RSET and SET-MH developed by the USGS fills the critical need for precise and easily replicable local surface elevation change measurements. The RSET-MH was developed to quantify the surface and shallow subsurface processes contributing to wetland surface elevation change (Figure 3.1). An RSET involves very simple technology; it consists of a benchmark rod driven through the soil profile (Figure 3.2) to resistance (typically 10-25 m depth), and a portable horizontal arm that is attached at a fixed point anchored in concrete (Figure 3.3) to measure the distance to the substrate surface, using vertical pins (Figure 3.4). Installation, maintenance and data collection require minor training, and this is being provided as in-kind support by USGS. Total surface height measurements have confidence intervals of ±1.3 mm, a figure well within the annual rate of eustatic SLR. RSETs are the only tool that can capture surface elevation change with this precision. RSET data are usually complemented with shallow accretionary monitoring using artificial soil marker horizons (MH) typically made of feldspar, which simultaneously quantify rates of vertical surface accretion (i.e., sediment deposition). The complete RSE/ MH setup provides net surface elevation change above the benchmark depth; moreover, as it has been repeatedly shown that vertical accretion is not a valid substitute for surface elevation change. The complete setup is necessary to identify the contribution of surface and shallow subsurface processes to surface elevation change at a specific site. Repeated measurements allow chronicling of net surface elevation change, which can be integrated with region-specific relative SLR (tide gauge data) to determine whether the surface elevation has kept pace with SLR over that time period. RSET data can inform assessments of wetland vulnerability to SLR and bolster SLR wetland models to support science-based policy. RSET networks will contribute to increased confidence in identifying coastal wetland vulnerability, to more informed science based policy, and to improved accuracy and efficiency of coastal conservation, mitigation, and adaptation responses. The USGS has established protocols for the installation of the RSET/MH technology and provided training sessions for this effort. USGS personnel were in the field during installation of our first six SETS to ensure quality control. USGS also has established protocols and templates for data collection and analysis and will provide these templates and training for this effort (Boumans 1993). USGS and WWU will provided this technical assistance as an in-kind effort for this project. Because of funding limitations only one restoration site with SET installations has so far been established in Puget Sound - Nisqually National Wildlife Refuge in the southern portion of the Sound. In addition to the USGS effort, researchers at Western Washington University have SET sites in northern Puget Sound (Kairis and Rybczyk 2010). Establishment of the SET/MH sites at Qwuloot and across the Snohomish River Estuary will provide valuable additional ...