Plum Island Ecosystems LTER Database

Acceptance and utilization of LTER data requires that:

(1) The Principal Investigator be sent a notice stating reasons for acquiring any data and a description of the publication intentions.
(2) The Principal Investigator of the data set be sent a copy of the report or manuscript prior to submission and be adequately cited in any resultant publications.
(3) A copy of any resultant publications should be sent to:

Principal Investigator
Ecosystems Center
Marine Biological Laboratory
7 MBL St.
Woods Hole, MA 02543

Dataset URLs:METADATA: HTML, Rich Text, XML(EML compliant)
DATA: Comma Delimited, Excel file with Metadata and data
Dataset ID:LTE-MP-SET-means.08
Dataset Title:Marsh surface elevation data (treatment means and stderr) from three marsh fertilization experimental research sites.
Investigator 1: 
First Name:Jim
Last Name:Morris
Address line 1:Dept of Biological Sciences
Address line 2:
Address line 3:University of SC
Zip Code:29208
Investigator 2: 
First Name:Karen
Last Name:Sundberg
Address line 1:Baruch Marine Field Laboratory
Address line 3:PO Box 1630
Zip Code:29442
Associate Investigators:Robert Daoust, Helen Marshall, Diana Rodriguez
Keywords:PIE LTER, Plum Island Ecosystems, Massachusetts, Rowley River, Parker River, organic matter, inorganic nutrients, SET, surface elevation, accretion, salt marsh, ammonium, phosphate, Typha, Spartina
Abstract:A Surface Elevation Table (SET) is used to measure changes in the elevation of the marsh surface at three long term marsh fertilization experimental research sites. The sites include one Typha-dominated brackish marsh, one Spartina alterniflora-dominated salt marsh, and one S. patens-dominated salt marsh. Sites are located on the Rowley and upper Parker Rivers in the Plum Island Ecosystem (PIE) LTER site.
Contact: Plum Island Ecosystems LTER Information Manager
The Ecosystems Center
Marine Biological Lab
7 MBL St
Woods Hole, MA 02543
Phone (508) 289 7485
Online URL:
Data File URL
Data File Name LTE-MP-SET-means
Beginning Date 6/29/1999
End Date 9/30/2013
Number of Data Records 330
Other Files to Reference LTE-MP-SET-raw
Availability Status type 1
Quality Control Information
Maintenance Description Collections occur every month from May through October. Database is updated once annually, usually in the winter. Study and data collection are ongoing as of Dec 2011.
Log of Changes: Version 01: July 11, 2006 Level 3+ EML using Jim Laundre's Excel program
Version 02: June 19, 2007, edited using Jim Laundre's Excel program (June 18, 2007 version)
Version 03: March 12, 2008 Data and metadata update
Version 04: February 17, 2009 Data and metadata update
Version 04: January 13, 2010 Data and metadata update
Version 05: October 25, 2011 Data and metadata update
Version 06: January 12, 2012, 2011 data and metadata update, using MarcrosExportEML_HTML (working)pie_excel2007.xlsm 1/12/12 11:51AM for QA/QC to EML 2.1.0
Version 07: March 15, 2013, 2012 data and metadata updated to comply with importation to Drupal and LTER PASTA. Research location name and description updated.Used MarcrosExportEML_HTML (working)pie_excel2007.xlsm 3/14/13 12:02 PM for QA/QC to EML 2.1.0
Version 08: April 17, 2014, 2013 data and metadata updated to comply with importation to Drupal and LTER PASTA. Research location name and description updated.Used MarcrosExportEML_HTML (working)pie_excel2007_Sep2013.xlsm 9/30/13 02:57 PM for QA/QC to EML 2.1.0
Geographic Description Law's Point on Rowley River, Rowley, MA, site of PIE LTER Spartina alterniflora plot level fertilization experiment. Law's Point on Rowley River, Rowley, MA, site of PIE LTER Spartina patens plot level fertilization experiment Upper Parker River off Orchard St., Newbury, MA, Typha sp. plot level fertilization experiment  
Location Bounding Box        
West Bounding Coordinate        
East Bounding Coordinate        
North Bounding Coordinate        
South Bounding Coordinate        
OR if single point location        
Latitude 42.731742 42.730954 42.756738  
Longitude -70.842472 -70.842915 -70.917717  
Taxonomic Protocols
Organisms studied Typha; Spartina alterniflora; Spartina patens
There are three on-going plot-level fertilization sites. The first (LTE-MP-LPA) is in the S. alterniflora-dominated low marsh at Law's Point between the Rowley River and West Creek. The second (LTE-MP-LPP) is in the S. patens-dominated high marsh at Law's Point between the Rowley River and West Creek. The third (LTE-MP-ORT) is in a Typha-dominated brackish water marsh on an upstream tributary of the Parker River. SET sampling at the LTE-MP-ORT)was discontinued after May 2008.

At each site a system of boardwalks was built to incorporate 12 experimental plots (1m2 each). There are 4 treatments (three reps each) within the boardwalk structure. The 4 treatments are Control, N-fertilized, P-fertilized, N+P fertilized. Additionally, at each site there are 3 control plots and 3 N+P fertilization plots external to the boardwalk structure. These external plots contain porewater samplers, and, in some cases, biomass census plots. In May 2006 the control porewater plots and control census plots at all three sites were moved because of potential contamination from fertilized plots.

Fertilizer is buried at several locations within each plot, approximately monthly, from May-Sept. From 1999-2001 the annual fertilization rate was 30 molN/m2/y and 15 mol P/m2/y. From 2002 to present fertilization rate is 7.5 mol N/m2/y and/or 3.75 mol P/m2/y. N fertilizer was NH4NO3 through 2008, and currently is nitrate/urea/sulfate (34-0-0). P fertilizer is P2O5 (0-44-0).

Sampling Description:
Triplicate original-style SET benchmark posts were installed between fertilized and control plots in 1999 at LTE-MP-LPA and 2000 at LTE-MP-LPP and LTE-MP-ORT. Each SET consists of a permanently-installed post and a removable arm. The arm has a vertical and a horizontal component. The vertical component fits into the SET benchmark post; the horizontal component reaches out over an experimental subplot and has a square plate at the end through which 9 pins are lowered. Each SET benchmark post is positioned such that 27 elevation readings can be taken in a fertilized plot (9 readings in each of 3 subplots) and 27 elevation readings can be taken in a control plot (9 readings in each of 3 subplots). Plots are numbered; subplots are identified as L, C, or R for left, center and right, when facing the plot (back to the SET post). To measure pin heights, the SET arm is locked in place over each subplot and the plate at the end of the arm is leveled. The 9 brass pins are then lowered to touch the sediment surface and held in place with a clip. Pin heights are measured from the top of the nut on the plate to the top of the pin, and read into a digital recorder. The recordings are transcribed into one master SET pin height data set. SET readings occur approximately monthly, from May-October at LTE-MP-LPA and LTE-MP-LPP, and in May and October only at LTE-MP-ORT. Sampling at the ORT SET was discontinued in 2008.

The horizontal portion of the removable part of the PIE LTER SET can be correctly installed and leveled in several positions: i.e. the arm can be extended all the way forward, all the way back, and anywhere in between. All SET measurements are made with the arm all the way back, i.e. with the plate being as close to the SET post as possible and the SET arm being as short as possible.

The SET was manufactured by Nolanís Machine Shop in Lafayette LA; 337-235-5261. Replacement pins or collars can be purchased from Nolanís. Stainless steel parts (roll pins etc) come from McMaster-Carr. Measuring pins are held in place with badge clips, available at office supply stores.

Data Processing:
Data are transcribed from a digital recorder to an Excel spreadsheet. Change in marsh elevation is determined by subtracting pin height at time X from the mean pin height for the subplot at time 0. SAS programs are used to determine treatment means and standard error for each month. (SAS System for Windows; release 9.1; SAS Institute, Inc; Cary, NC)

LTE-MP-LPA, approx 1.1 meters NAVD88
LTE-MP-LPP, approc 1.4 meters NAVD88

Data Table

Variable Name Variable Description Units Measurement Scale Code Information Number Type DateTime Format Missing Value Code Missing Value Code Explanation
SITE current name of sampling station, following naming protocol   nominal          
TRT treatment   nominal NP=fertilized | C=control        
MONTH month   nominal     mm    
DAY day   datetime     dd    
YEAR year   datetime     yyyy    
MEAN ELEV CHANGE (cm) treatment mean change in height of marsh surface since beginning of experiment (cm) centimeter ratio   real   . .=not measured
STDERR treatment standard error centimeter ratio   real   . .=not measured