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-2001.01
Dataset Title:Year 2001, 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:Charles
Last Name:Vorosmarty
Address line 1:Morse Hall
Address line 2:UNH
Address line 3:
City:Durham
State:NH
Zip Code:03824
Country:USA
Investigator 2: 
First Name:Wilfred
Last Name:Wollheim
Address line 1:Morse Hall
Address line 2:UNH
City:Durham
State:NH
Zip Code:03824
Country:USA
Associate Investigators: Brian Pellerin
Keywords:PIE LTER, Cart Cr, forest, discharge, water temperature, conductivity, pH, dissolved oxygen.
Abstract:Continuous measurements, every 15 minutes, were made of stage, water temperature, conductivity, dissolved oxygen, and pH in 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
Email: pie_im@mbl.edu
Online URL: http://ecosystems.mbl.edu/PIE/
DATA FILE INFORMATION:
Data File URL http://ecosystems.mbl.edu/PIE/data/WAT/data/WAT-YSI-Forest-2001.dat
Data File Name WAT-YSI-Forest-2001
Beginning Date 6/21/2001
End Date 12/31/2001
Number of Data Records 16344
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 updated in September 2007 to incorporate an improved rating curve that includes higher discharge events. Flow data from previous version is maintained for comparison.
RESEARCH LOCATION: Site 1
Geographic Description YSI-CC
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
Methods: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.

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

STATION STATE X STATE Y
YSI-CC 247680 946790

NOTES AND COMMENTS:

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.

This file includes a column called OLD-Discharge, which uses an earlier rating curve with fewer points, a smaller range of depth. This is maintained for comparison with the new and improved rating curve. 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.


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


OLD RATING CURVE ( prior to Sept 2007 revision):
Discharge measurements in Cart Creek are based on an exponential rating curve that contains measurements up to a depth of 0.475m (Using the column YSI_Depth). Flows above this amount are estimated using a linear extrapolation using the six measurements with the highest flow. Thus flows determined from levels greater than 0.475m are approximate (0 % of the readings in 2001 deployment period). Rating curve below 0.475m is based on an exponential relationship with an R2 = 0.99. Measurements are based on 17 measurements taken between 2001 and 2003.

OLD CALCULATIONS (NO LONGER USED):
When stage in Cart Cr. is less than 0.475m :
Discharge (l/s) = 0.2481 * 2.71828 ^ (12.389 * depth)

When stage in Cart Cr. is greater than 0.475m :
Discharge (l/s) = 629.7 * depth – 212.8

where depth = YSI_Depth

Data Table

Variable Name Variable Description Units Measurement Scale Code Infomation Number Type DateTime Format Missing Value Code Missing Value Code Explanation
Date date (yyyy-mm-dd)   datetime     yyyy-mm-dd   blank cell
Time time (hh:mm) 24 hour   datetime     hh:mm   blank cell
Temp water temperature (oC) celsius interval   real     blank cell
SpCond specific conductivity (mS/cm) millisiemensPerCentimeter ratio   real     blank cell
DO% dissolved oxygen percent of saturation (%) percent ratio   real     blank cell
DOConc dissolved oxygen concentration (mg/l) milligramsPerLiter ratio   real     blank cell
pH log of the H+ ion concentration dimensionless ratio   real     blank cell
YSI_Depth stage height measured by YSI (m) meter ratio   real     blank cell
OLD-Discharge discharge using YSI_Depth and earlier rating curve (l/s) litersPerSecond ratio   real     blank cell
HOBO_Depth stage height standardized to HOBO depth (m) meter ratio   real     blank cell
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       blank cell
Discharge discharge litersPerSecond ratio   real     blank cell