TITLE
Sulfate isotopes in precipitation and streamwater
PRINCIPAL INVESTIGATOR(s)
Christine
Alewell
University of Basel
Institute of Environmental Geosciences
Department of Geosciences
Bernoullistrasse 30
Basel CH-4056
Switzerland
Email: christine.alewell@unibas.ch
University of Basel
Institute of Environmental Geosciences
Department of Geosciences
Bernoullistrasse 30
Basel CH-4056
Switzerland
Email: christine.alewell@unibas.ch
Gene
Likens
Institute of Ecosystems Studies
65 Sharon Turnpike
P.O. Box AB
Millbrook , NY 12545
USA
Email: LikensG@ecostudies.org
Institute of Ecosystems Studies
65 Sharon Turnpike
P.O. Box AB
Millbrook , NY 12545
USA
Email: LikensG@ecostudies.org
OTHERS INVOLVED
Roy
Krouse
BEGIN DATE
1966-01-01
END DATE
1994-12-31
LOCATION
Precip Watershed 6 (Raingage 11)
West bounding coordinate: -71.735443
East bounding coordinate: -71.735443
North bounding coordinate: 43.950092
South bounding coordinate: 43.950092
East bounding coordinate: -71.735443
North bounding coordinate: 43.950092
South bounding coordinate: 43.950092
Precip RG (Raingage 22 at Robert S. Pierce Ecosystem Laboratory)
West bounding coordinate: -71.701859
East bounding coordinate: -71.701859
North bounding coordinate: 43.943943
South bounding coordinate: 43.943943
East bounding coordinate: -71.701859
North bounding coordinate: 43.943943
South bounding coordinate: 43.943943
Stream Watershed 6 (at the weir)
West bounding coordinate: -71.735641
East bounding coordinate: -71.735641
North bounding coordinate: 43.949940
South bounding coordinate: 43.949940
East bounding coordinate: -71.735641
North bounding coordinate: 43.949940
South bounding coordinate: 43.949940
Stream Watershed 5 (at the weir)
West bounding coordinate: -71.731918
East bounding coordinate: -71.731918
North bounding coordinate: 43.948845
South bounding coordinate: 43.948845
East bounding coordinate: -71.731918
North bounding coordinate: 43.948845
South bounding coordinate: 43.948845
ABSTRACT
Sulfur deposition in the northeastern U.S. has been decreasing since
the 1970s and there has been a concomitant decrease in the SO4 lost from drainage
waters from forest catchments of this region. It has been established previously
that the SO4 lost from drainage waters exceeds SO4 inputs in bulk precipitation, but
the cause for this imbalance has not been resolved. The use of stable S isotopes and
the availability of archived bulk precipitation and stream water samples at the
Hubbard Brook Experimental Forest (HBEF) in New Hampshire provided a unique
opportunity to evaluate potential sources and sinks of S by analyzing the long-term
patterns (1966–1994) of the d34S values of SO4 . In bulk precipitation adjacent to
the Ecosystem Laboratory and near Watershed 6 the d34S values were greater (mean:
4.5 and 4.2l, respectively) and showed more variation (variance: 0.49 and 0.30) than
stream samples from Watersheds 5 (W5) and 6 (W6) (mean: 3.2 and 3.7; variance: 0.09
and 0.08, respectively). These results are consistent with other studies in forest
catchments that have combined results for mass balances with stable S isotopes.
These results indicate that for those sites, including the HBEF, where atmospheric
inputs are 10 kg S ha-1 yr-1, most of the deposited SO4 cycles through the biomass
before it is released to stream water. Results from W5, which had a whole-tree
harvest in 1983–1984 showed that adsorption/desorption processes play an important
role in regulating net SO4 retention for this watershed-ecosystem. Although the
isotopic results suggest the importance of S mineralization, conclusive evidence
that there is net mineralization has not yet been shown. However, S mass balances
and the isotopic result are consistent with the mineralization of organic S being a
major contributor to the SO4 in stream waters at the HBEF.
METHODS
At both W5 and W6, stream samples are collected weekly just above the
weirs which are used for measuring stream flow. Archived solutions, which had been
stored in clean polyethylene bottles, collected from 1966 through 1994 were sampled.
The policy of the Hubbard Brook Ecosystem Study is to allow each approved request to
sample no more than 10% of the volume of the archived samples. To yield sufficient
sulfate for the stable isotope analysis, weekly samples of the solutions were
subsampled and combined to form composited half-year samples divided into “summer”
(June 1 through November 30) and “winter” (December 1 through May 31) samples that
encompass the water year that begins on June 1 and ends on May 31 of the next
calendar year. These composited water samples then were analyzed for sulfate with
ion Chromatography at SUNY-ESF. Sulfate in the solutions was precipitated as BaSO4
by adding BaCl2 and the S isotopic composition of the BaSO4 measured on-line with an
elemental analyzer coupled to an isotope ratio mass spectrometer.
REFERENCES
- Alewell , C., Mitchell , M. , Likens , G. , and Krouse , R. 1999 . ources of stream sulfate at the Hubbard Brook Experimental Forest: long-term analysis using stable isotopes. Biogeochemistry 44: 281-299.
DATA ACCESS GUIDELINES
The access to all LTER data is subject to requirements set forth by this
policy document to enable data providers to track usage, evaluate its impact in the
community, and confirm users' acceptance of the terms of acceptable use. These
requirements are standardized across the LTER Network to provide contractual exchange of
data between Site Data Providers, Network Data Providers, and Data Users that can be
encoded into electronic form and exchanged between computers. This will allow direct
access to data via a common portal once these requirements have been fulfilled. The
following information may be required directly or by proxy prior to the transference of
any data object:
Registration
Name
Affiliation
Email address
Full Contact Info
Acceptance of the General Public Use Agreement or Restricted Data Use Agreement, as applicable
A Statement of Intended Use that is compliant with the above agreements. Such statements may be made submitted explicitly or made implicitly via the data access portal interface.
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:
Acceptable Use. Use of the dataset will be restricted to academic, research, educational, government, recreational, or other not-for-profit professional purposes. The Data User is permitted to produce and distribute derived works from this dataset provided that they are released under the same license terms as those accompanying this Data Set. Any other uses for the Data Set or its derived products will require explicit permission from the dataset owner.
Redistribution. The data are provided for use by the Data User. The metadata and this license must accompany all copies made and be available to all users of this Data Set. The Data User will not redistribute the original Data Set beyond this collaboration sphere.
Citation. It is considered a matter of professional ethics to acknowledge the work of other scientists. Thus, the Data User will properly cite 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.
Acknowledgement. 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 significantly to its content. Acknowledgements should identify the supporting party, the party that received the support, and any identifying information such as grant numbers.
Notification. The Data User will notify the Data Set Contact when any derivative work or publication based on or derived from the Data Set is distributed. The Data User will provide the data contact with two reprints of any publications resulting from use of the Data Set and will provide copies, or on-line access to, any derived digital products. Notification will include an explanation of how the Data Set was used to produce the derived work.
Collaboration. The Data Set has been released in the spirit of open scientific collaboration. Data Users are thus strongly encouraged to consider consultation, collaboration and/or co-authorship with the Data Set Creator.
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.
By viewing or downloading the data, I certify that I accept the conditions herein
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.
Digital data and its metadata derived from any research activity such as field observations, collections, laboratory analysis, experiments, or the post-processing of existing data and identified by a unique identifier issued by a recognized cataloging authority such as a site, university, agency, or other organization.
ndividual to whom access has been granted to this Data Set, including his or her immediate collaboration sphere, defined here as the institutions, partners, students and staff with whom the Data User collaborates, and with whom access must be granted, in order to fulfill the Data User's intended use of the Data Set
individual or institution that produced the Data Set
individual or institution that holds intellectual property rights to the dataset. Note that this may or may not be defined as a legal copyright. If no other party is designated in the metadata as Data Set Owner, it may be presumed that these rights are held by the Data Set Creator.
individual or institution providing access to the Data Sets.
party designated in the accompanying metadata of the Data Set as the primary contact for the Data Set.
Registration
Name
Affiliation
Email address
Full Contact Info
Acceptance of the General Public Use Agreement or Restricted Data Use Agreement, as applicable
A Statement of Intended Use that is compliant with the above agreements. Such statements may be made submitted explicitly or made implicitly via the data access portal interface.
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:
Acceptable Use. Use of the dataset will be restricted to academic, research, educational, government, recreational, or other not-for-profit professional purposes. The Data User is permitted to produce and distribute derived works from this dataset provided that they are released under the same license terms as those accompanying this Data Set. Any other uses for the Data Set or its derived products will require explicit permission from the dataset owner.
Redistribution. The data are provided for use by the Data User. The metadata and this license must accompany all copies made and be available to all users of this Data Set. The Data User will not redistribute the original Data Set beyond this collaboration sphere.
Citation. It is considered a matter of professional ethics to acknowledge the work of other scientists. Thus, the Data User will properly cite 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.
Acknowledgement. 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 significantly to its content. Acknowledgements should identify the supporting party, the party that received the support, and any identifying information such as grant numbers.
Notification. The Data User will notify the Data Set Contact when any derivative work or publication based on or derived from the Data Set is distributed. The Data User will provide the data contact with two reprints of any publications resulting from use of the Data Set and will provide copies, or on-line access to, any derived digital products. Notification will include an explanation of how the Data Set was used to produce the derived work.
Collaboration. The Data Set has been released in the spirit of open scientific collaboration. Data Users are thus strongly encouraged to consider consultation, collaboration and/or co-authorship with the Data Set Creator.
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.
By viewing or downloading the data, I certify that I accept the conditions herein
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.
Digital data and its metadata derived from any research activity such as field observations, collections, laboratory analysis, experiments, or the post-processing of existing data and identified by a unique identifier issued by a recognized cataloging authority such as a site, university, agency, or other organization.
ndividual to whom access has been granted to this Data Set, including his or her immediate collaboration sphere, defined here as the institutions, partners, students and staff with whom the Data User collaborates, and with whom access must be granted, in order to fulfill the Data User's intended use of the Data Set
individual or institution that produced the Data Set
individual or institution that holds intellectual property rights to the dataset. Note that this may or may not be defined as a legal copyright. If no other party is designated in the metadata as Data Set Owner, it may be presumed that these rights are held by the Data Set Creator.
individual or institution providing access to the Data Sets.
party designated in the accompanying metadata of the Data Set as the primary contact for the Data Set.
CONTACT PERSON
Data file:
sulfur_isotopes
Description: Sulfate isotopes in precipitation and streamwater
CODES
Description: Sulfate isotopes in precipitation and streamwater
| Column | Variable | Description | Units | Coded? | Missing value label |
| 1 | YEAR | Year sample was collected | YYYY | n | none |
| 2 | SAMPLE_TYPE | Sample type | none | y | none |
| 3 | LOCATION | Location where sample was collected | none | y | none |
| 4 | SEASON | Season sample was collected | none | y | none |
| 5 | d34S | Delta 34S (per mil) | perMil | n | -9999.99 |
| 6 | SO4 | Sulfate concentration | microMolesPerLiter | n | -9999.9 |
Variable: SAMPLE_TYPE
|
Code
|
Description
|
|
precip
|
Precipitation sample
|
|
stream
|
Stream sample
|
|
Code
|
Description
|
|
W6
|
Watershed 6
|
|
W5
|
Watershed 5
|
|
RG
|
Rain gage 22
|
|
Code
|
Description
|
|
Winter
|
December 1 through May 31
|
|
Summer
|
June 1 through November 30
|