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-LPP-biomass.10
Dataset Title:Aboveground biomass of Spartina patens at Law's Point salt marsh on the Rowley River.
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, primary production, nutrients, aboveground biomass, salt marsh, nutrient cycling, Spartina patens
Abstract:Aboveground biomass is determined destructively during the growing season at a Spartina patens salt marsh on the Rowley River within the Plum Island Ecosystems (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-LPP-biomass
Beginning Date 8/24/2000
End Date 9/30/2013
Number of Data Records 540
Other Files to Reference
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 2013.
Log of Changes: Version 01: July 11, 2006 Level 3+ EML using Jim Laundre's Excel program
Version 02: January 10, 2007 data and metadata update
Version 03: March 12, 2008 Data and metadata update
Version 04: February 20, 2009 Data and metadata update
Version 05: January 13, 2010 Data and metadata update
Version 06: October 25, 2011 Data and metadata update
Version 07: 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 08: March 22, 2012 edited missing values for comment variable
Version 09: March 14, 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 10: April 18, 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 patens 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 42.730954  
Longitude -70.842915  
Taxonomic Protocols
Organisms studied Spartina patens
This data set is part of a study including three on-going plot-level fertilization sites. The first (LTE-MP-LPA) is in the low marsh at Law's Point along the Rowley River. The second (LTE-MP-LPP) is in the high marsh at Law's Point along the Rowley River. The third (LTE-MP-ORT) is in a brackish water marsh on an upstream tributary of the Parker River. Biomass sampling is slightly different at each site, and is accomplished non-destructively at the LTE-MP-LPA and LTE-MP-ORT sites, and destructively at the LTE-MP-LPP site. Biomass sampling at LTE-ME-ORTwas discontinued after August 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, 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:
The plant census method at LPP is destructive. One randomly placed 10x10 cm quadrat is clipped approximately monthly from May to October from each of 3 Control plots and 3 NP plots located outside of the boardwalk. Plants are clipped to 1 cm from the marsh surface and placed into a labelled plastic bag. Live and dead plants are separated, and live plants are separated species. Plants are placed into labelled paper bags, dried at 60C and weighed.

LPP census plots were established in August 2000. From 2000-2003, biomass was estimated for all 4 treatments. It is assumed that biomass was clipped from N plots and P plots within the boardwalk even though this was destructive. Biomass was not clipped from the C plots and NP plots within the boardwalk because these were also SET plots. Instead, 3 additional Control and 3 additional NP plots were established that were external to the boardwalk. Beginning in spring 2004, biomass was collected only from the external C and NP plots; biomass collection from the N plots and P plots was discontinued.

Data processing:
All data are entered into an Excel spreadsheet where mean treatment biomass in gdw/m2 are determined.

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          
YEAR year   datetime     yyyy    
MONTH month   datetime     mm    
DAY day of month   datetime     dd    
PLOT plot identification number   nominal          
TRT treatment   nominal N=fertlized with nitrogen only | P= fertilized with phosphorus only | NP=fertilized with nitrogen and phosphorus | C=control (not fertilized)        
SP biomass biomass of live Spartina patens (dry weight) gramPerMeterSquared ratio   real   . .=not sampled
DS biomass biomass of live Distichlis spicata (dry weight) gramPerMeterSquared ratio   real   . .=not sampled
SA biomass biomass of live Spartina alterniflora (dry weight) gramPerMeterSquared ratio   real   . .=not sampled
SE biomass biomass of live Salicornia europa (dry weight) gramPerMeterSquared ratio   real   . .=not sampled
LIVE biomass biomass of all live vegetation (dry weight) gramPerMeterSquared ratio   real   . .=not sampled
DEAD biomass biomass of all dead vegetation (dry weight) gramPerMeterSquared ratio   real   . .=not sampled