Chemistry of Streamwater at the Hubbard Brook Experimental Forest, Watershed 9, 1995 - present
Chemistry of Streamwater at the Hubbard Brook Experimental Forest, Watershed 9, 1995 - present
Gene E. Likens
Cary Institute of Ecosystem Studies
2801 Sharon Turnpike
Millbrook, NY 12545

Phone: (845) 677-5343
Streamwater chemistry has been measured at the Hubbard Brook Experimental Forest since 1963. These data include volume-weighted, average, monthly concentrations of cations, anions, and pH measured in 9 watersheds. Monthly averages are calculated from samples collected at weekly intervals from a point above the stream gauging station.
KEYWORD SET: Hubbard Brook Ecosystem Study LTER
aluminum, ammonium, calcium, chemistry, chloride, flow, HBEF Watershed 9, HBR, Hubbard Brook LTER, magnesium, nitrate, pH, phosphate, potassium, silica, sodium, stream, sulfate, watershed.
KEYWORD SET: LTER Core Research Areas
disturbance, inorganic nutrients.
HBEF watershed 9 (WS-9). Collected from a waterfall 5m above the stream gauging station at HBEF WS-9.
West bounding coordinate: -71.747185
East bounding coordinate: -71.747185
North bounding coordinate: 43.926014
South bounding coordinate: 43.926014
Samples are collected in acid-washed, deionized water-rinsed, polyethylene bottles, from a small waterfall above the stream gauging station, to avoid contamination from ponded debris or weir construction materials. The normal sampling interval is weekly, with more frequent samples taken at times of increased discharge. At low flow summer (drought) conditions, samples may be taken with a clean polyethylene syringe, from undisturbed standing pools in the stream channel.
Daily export values (in g/ha-mo) are derived by multiplying daily streamflow amounts (in mm) for watershed 9, by the concentration of solutes (in mg/L) in the WS-9 sample taken on that day. For periods between samples, the average chemistry of the previous and next discrete sample is used for a daily concentration value. Measured and estimated daily values are summed to produce monthly export, and export divided by total monthly streamflow to produce volume-weighted, average monthly concentrations for streamwater at HBEF WS-9.
In June 2013, after careful inter-laboratory comparisons, chemical analyses were transferred from the Cary Institute of Ecosystem Studies Lab to the USDA Forest Service Lab in Durham, NH. Samples are split into 3 aliquots for different analyses. Monomeric Aluminum is measured on an unfiltered-refrigerated aliquot using an automated Pyrocatechol Violet method. A filtered-refrigerated aliquot is acidified and analyzed for cations and metals using ICP-OES (USEPA 200.7). A filtered-frozen sample is used for measuring NH4 (USEPA 350.1 Rev. 2.0), PO4 (USEPA 365.1 Rev. 2.0), Anions (USEPA 300.1) , DOC (USEPA 450.1) and TDN (High Temperature Catalytic Oxidation with chemiluminescent N detection).
  • Buso, D.C., Likens, G.E., and Eaton, J.S. 2000. Chemistry of precipitation, streamwater, and lakewater from the Hubbard Brook Ecosystem Study: a record of sampling protocols and analytical procedures. USDA Forest Service, Northeastern Research Station Gen. Tech. Rep. NE-275. 52 pp. USDA Forest Service, Newtown Square, PA.
  • Federer, C.A., Flynn, L.D., Martin, C.W., Hornbeck, J.W., and Pierce, R.S. 1990. Thirty years of hydrometeorologic data at the Hubbard Brook Experimental Forest, New Hampshire. USDA Forest Service, Northeastern Research Station Gen. Tech. Rep. NE-141. 44 pp. USDA Forest Service, Newtown Square, PA.
  • Likens, G.E., Bormann, F.H., Pierce, R.S., Eaton, J.S., and Johnson, N.M. 1977. Biogeochemistry of a Forested Ecosystem. Springer-Verlag New York Inc. 146 pp.
  • Likens, G.E., and Buso, D.C. 2006. Variation in streamwater chemistry throughout the Hubbard Brook Valley. Biogeochemistry 78:1-30.
  • Likens, G.E., and Buso, D.C. 2012. Dilution and the elusive baseline. Environmental science and technology 46(8):4382-4387.
Data Access Guidelines for Streamwater Chemistry

We are happy to share these data on the chemistry of Hubbard Brook ecosystems. The public dissemination of these data that we have collected is a responsibility that we take very seriously. As stewards of these long-term data, our highest priorities are:

a. to maintain the integrity of these long-term data;

b. to allow adequate time for the analysis, quality assurance, and publication of results by principal investigators;

c. to acknowledge properly and responsibly the appropriate funding sources.

Therefore, it is HBES policy to make these streamwater data available on this web page two years after the date of collection. Also, in sharing these data with users like yourself, we ask that you adhere to the following guidelines as a matter of common courtesy and ethical responsibility:

1. Please inform us in advance of your interest and plans for use of these data (

2. The sources of funding used to collect these data must be acknowledged properly. We will provide the appropriate information when we learn what data are being used.

3. We would like to review any manuscripts that utilize extensive amounts (e.g. multiple years) of these data. If data use is extensive, or if these data have not been published previously, it may be appropriate for us to be included as authors on publication that are generated given the additional requirements from us for analysis and interpretation.

Data Use Policy

The re-use of scientific data has the potential to greatly increase communication, collaboration and synthesis within and among disciplines, and thus is fostered, supported and encouraged. Permission to use this dataset is granted to the Data User free of charge subject to the following terms:

1) Acceptable use. Use of the dataset will be restricted to academic, research, government or other not-for-profit professional purposes.

2) Redistribution. The data and metadata are provided for use by the Data User. The Data User will not redistribute the original Data Set or metadata to others without the explicit permission of the Principal Investigator.

3) Citation. It is considered a matter of professional ethics to acknowledge the work of other scientists. Thus, the Data User will properly attribute the Data Set in any publications or in the metadata of any derived data products that were produced using the Data Set. Citation should take the following general form: Creator, Year of Data Publication, Title of Dataset, Publisher, Dataset identifier.

Citation example: Holmes, R.T. 2012. Bird Abundances at Hubbard Brook (1969-2010) and on three replicate plots (1986-2000) in the White Mountain National Forest. Durham, NH. Hubbard Brook Data Archive [Database]. (23 July 2012)

4) Acknowledgment: The Data User should acknowledge any institutional support or specific funding awards referenced in the metadata accompanying this dataset in any publications where the Data Set contributed to its content. Acknowledgments should identify the supporting party, the party that received the support, and any identifying information such as grant numbers.

Acknowledgment example: Data on [topic] were provided by [name of PI] on [date]. These data were gathered as part of the Hubbard Brook Ecosystem Study (HBES). The HBES is a collaborative effort at the Hubbard Brook Experimental Forest, which is operated and maintained by the USDA Forest Service, Northern Research Station, Newtown Square, PA. Significant funding for collection of these data was provided by [agency]-[grant number], [agency]-[grant number], etc.

5) Consultation and questions. Data users are strongly encouraged to consult with the Principal Investigator(s) who collected these data for further information. Also, when appropriate, Data Users should consider including the Principal Investigator as a collaborator and/or co-author in the use of these data.

6) Notification. The Data User will notify the Principal Investigator of any publication or derivative work based on the Data Set. The Data User will also provide the Principal Investigator and/or the administrator of the Hubbard Brook Ecosystem Study with a pdf or two reprints of any publication(s) resulting from use of the Data Set.

7) Disclaimer. While substantial efforts are made to ensure the accuracy of data and documentation contained in this Data Set, complete accuracy of data and metadata cannot be guaranteed. All data and metadata are made available "as is". The Data User holds all parties involved in the production or distribution of the Data Set harmless for damages resulting from its use or interpretation.

8) Terms of Agreement. By accepting this Data Set, the Data User agrees to abide by the terms of this agreement. The Data Owner shall have the right to terminate this agreement immediately by written notice upon the Data User's breach of, or non-compliance with, any of its terms. The Data User may be held responsible for any misuse that is caused or encouraged by the Data User's failure to abide by the terms of this agreement.


Information Manager, Hubbard Brook LTER
234 Mirror Lake Road
North Woodstock, NH 03262

Phone: (603) 726-8902

Data file: w9_stream_chem.txt
Description: Stream chemistry data of watershed 9 at Hubbard Brook LTER
Notes on Data: DATA DESCRIPTION Volume-weighted, average, monthly concentrations in streamwater. Data are only used to calculate solute export for HBEF Watershed 9. Routine collections began in June 1995. These data are physically located at the Cary Institute of Ecosystem Studies, Robert S. Pierce Ecosystem Laboratory, Hubbard Brook Experimental Forest, W. Thornton, NH. NOTE REGARDING NITRATE DATA: After careful and exhaustive inter- and intra-laboratory tests we determined that nitrate concentrations in stream water were no longer remaining stable after collection, as they had in the past (see Buso, Likens and Eaton 2000). It is possible that the biological community in some streams of the HBEF has changed in recent years, affecting the nitrate concentration in complicated ways. While there was no systematic bias to the data, the situation occurred primarily during summer, when nitrate concentrations and streamflows are very low. Thus, we urge some caution in using the streamwater nitrate data collected since 2006, when nitrate stability was last confirmed. In 2013, new protocols were instituted to prevent decay of nitrate concentrations after collection and the problem has been resolved. There is no evidence that nitrate concentrations in the long-term precipitation record have been affected.
ColumnVariableDescriptionUnitsCoded?Missing value label
4flowtotal streamflow in mm/month (over any unit of area)millimeterPerMonthn
5Cacalcium concentration in mg/LmilligramPerLitern
6Mgmagnesium concentration in mg/LmilligramPerLitern
7Kpotassium concentration in mg/LmilligramPerLitern
8Nasodium concentration in mg/LmilligramPerLitern
9Altotal aluminum in mg/LmilligramPerLitern
10NH4ammonium concentration in mg/LmilligramPerLitern
12SO4sulfate concentration in mg/LmilligramPerLitern
13NO3nitrate concentration in mg/LmilligramPerLitern
14Clchloride concentration in mg/LmilligramPerLitern
15PO4phosphate concentration in mg/L (soluble-reactive phosphate)milligramPerLitern
16SiO2silica concentration in mg/L (measured as silicate)milligramPerLitern


Variable: ws
the number of the watershed is 9 throughout this dataset

Missing Value Code
Code Explanation
Data missing or not taken
Data missing or not taken
Data missing or not taken
Data missing or not taken
Data missing or not taken
Data missing or not taken
Data missing or not taken
Data missing or not taken
Data missing or not taken
Data missing or not taken
Data missing or not taken
Data missing or not taken
Data missing or not taken