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:WAT-YSI-Forest-2004.03
Dataset Title:Year 2004, 15 minute measurements of stage, water temperature, conductivity, dissolved oxygen, and pH in a small headwater stream draining draining a mainly forested catchment (55% forest + 19% wetland), Cart Cr., Newbury, MA.
Investigator 1: 
First Name:Wilfred
Last Name:Wollheim
Address line 1:Morse Hall
Address line 2:UNH
Address line 3:
Zip Code:03824
Associate Investigators: Brian Pellerin
Keywords:PIE LTER, disturbance, Parker River watershed, Cart Creek, forest, discharge, water temperature, water stage, conductivity
Abstract:Continuous measurements, every 15-30 minutes, were made of stage, water temperature, conductivity, dissolved oxygen, and pH in Cart Creek, Newbury, MA, a small headwater stream draining a mainly forested catchment (55% forest + 19% wetland). Measurements are for part of the ice free season (June December). Discharge is determined from stage using discharge vs stage regressions. Several day gaps occur periodically due to removal for recalibration.
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 WAT-YSI-Forest-2004
Beginning Date 3/24/2004
End Date 12/31/2004
Number of Data Records 19967
Other Files to Reference All in the YSI series.
Availability Status Type 1
Quality Control Information
Maintenance Description Periodic with improvement of rating curve, particularly as more high discharge events are incorporated.
Log of Changes: This file was initially posted in September 2007.
Version 01, 30 Oct 2007 updated metadata to EML level 3+
Version 02, 21Jan2010 keyword update
Version 03, 15May2013, metadata and data updated to comply with importation to Drupal and LTER PASTA. Used MarcrosExportEML_HTML (working)pie_excel2007.xlsm 3/14/13 12:02 PM for QA/QC to EML 2.1.0
Geographic Description Watershed water collection and stream characterization site for Cart Creek (forest landuse), Newbury, MA  
Location Bounding Box    
West Bounding Coordinate    
East Bounding Coordinate    
North Bounding Coordinate    
South Bounding Coordinate    
OR if single point location    
Latitude 42.7692  
Longitude -70.9165  
Taxonomic Protocols
Organisms studied
In addition to the YSI information collected as in previous years, this file includes depth measured by the Sigma Autosampler. We generally rely on depth measured by the YSI, as these are more reliable. We rely on the Sigma measurements for discharge for the last nine days in December 2004.

YSI: YSI 6200 data sondes were deployed vertically in a pool deep enough to contain water during dry conditions. The sonde was deployed in a PVC tube, which was attached to ree-bar driven into the stream bed. The PVC tube had holes drilled to allow adequate water circulation. Dissolved oxygen measurements are of good quality because detritus did not accumulate in the bottom of the pool (unlike our suburban site).

The PVC tube was surveyed upon original deployment in 2001 and resurveyed in 2002 to ensure that elevation did not change during winter ice period. No change was detected. No evidence of change has been noted through 2006 based on discharge measurements. See discussion below for development of the discharge-stage relationship.

Recalibration of oxygen, pH, conducitivty and depth was performed roughly every 4-6 weeks. Instrument drift during deployment periods was not significant.

SIGMA AUTOSAMPLER: Depth is also recorded at times using a depth sonde integrated with the Sigma autosampler. Sonde was secured to cinder block driven into the stream bottom and referenced to standardized depth. Discharge reported by the Sigma is included for when the autosampler was programmed to sample on a flow weighted basis. Sigma discharge is based on a rating curve programmed into the Sigma that is based on the old rating curve developed prior to 2004 and is therefore approximate.

When available, YSI depth is used in preference to Sigma depth to determine discharge because the latter is less reliable. Sigma depth is used for discharge from from 2004-12-23 to 2004-12-31. Sigma depth is referenced to YSI depth based on overlap of readings prior to Dec 23 2004, and then further corrected to the HOBO depth. YSI_Depth = Sigma_Depth - 0.032. HOBO_Depth = YSI_Depth + 0.17549. Discharge when Depth_Device = SIGMA should be used with caution because of instrument unreliability and the several conversions that are made to standardize the depth.

ADDITIONAL RESEARCH LOCATION COORDINATES: In addition to the decimal degree coordinates given above, locations are also given here in Massachusetts State Plane coordinates. The stream is called Cart Cr. and is located in Newbury MA. Some residential area is present. (~ 10% of the basin). In addition, I-95 passes through the center of the catchment, resulting in roughly 8% impervious surface area

YSI-CC 247680 946790


Velocity measurements were made using a Marsh McBirney current meter. Discharge estimates in Cart Cr. are based on a power rating curve that contains measurements up to a depth of 0.8 meters, as standardized to depth measured with a HOBO datalogger (Column = HOBO_Depth), which is above bankfull stage. Rating curve has been standardized to HOBO_Depth to allow application of a single rating curve across years. Rating curve has an R2 of 0.96 using 32 measurements between 2001 and 2007. All files in this series (2001-2006) are currently standardized to HOBO_depth.

The column Depth_Device is included when combining files from several years, over which several different devices were used to calculate depth. HOBO_Depth is the depth that is standardized across all measurement devices so that a single rating curve can be applied.

Discharge rating curve :
Discharge (l/s) = 731.91 (depth) ^ 5.5172
where depth is HOBO_Depth

Data Table

Variable Name Variable Description Units Measurement Scale Code Information Number Type DateTime Format Missing Value Code Missing Value Code Explanation
Date date (yyyy-mm-dd)   datetime     yyyy-mm-dd NA NA = not available
Time time (hh:mm) 24 hour   datetime     hh:mm NA NA = not available
Temp water temperature (oC) celsius interval   real   NA NA = not available
SpCond specific conductivity (mS/cm) millisiemenPerCentimeter ratio   real   NA NA = not available
DO% dissolved oxygen percent of saturation (%) percent ratio   real   NA NA = not available
DOConc dissolved oxygen concentration (mg/l) milligramPerLiter ratio   real   NA NA = not available
pH log of the H+ ion concentration dimensionless ratio   real   NA NA = not available
YSI_Depth stage height measured by YSI (m) meter ratio   real   NA NA = not available
SIGMA_DEPTH stage height measured by SIGMA (m) meter ratio   real   NA NA = not available
SIGMA_FLOW discharge using SIGMA_Depth and earlier rating curve (l/s) literPerSecond ratio   real   NA NA = not available
HOBO_Depth stage height standardized to HOBO depth (m) meter ratio   real   NA NA = not available
Depth_Device depth measurement device used to determine discharge   nominal YSI = YSI depth sonde | SIGMA = Sigma autosampler depth sonde | TEMP_HOBO = HOBO depth sonde deployed in temporary stilling well | HOBO = HOBO depth sonde deployed in permanent stilling well     NA NA = not available
Discharge discharge literPerSecond ratio   real   NA NA = not available