TITLE
Forest Floor Mass, Organic Matter and Chemistry (Ca, Mg and some trace metals): Watershed 6 (the reference watershed) in 1976
PRINCIPAL INVESTIGATOR(s)
Thomas G.
Siccama
Yale School of Forestry and Environmental Studies
New Haven, CT 06511
USA
Yale School of Forestry and Environmental Studies
New Haven, CT 06511
USA
OTHERS INVOLVED
Chuck
Peters
New York Botanical Garden
Bronx, NY 10458
USA
New York Botanical Garden
Bronx, NY 10458
USA
Gene
Likens
Institute of Ecosystem Studies
Millbrook, NY 12545
USA
Institute of Ecosystem Studies
Millbrook, NY 12545
USA
F.H.
Bormann
Yale School of Forestry and Environmental Studies
New Haven, CT 06511
USA
Yale School of Forestry and Environmental Studies
New Haven, CT 06511
USA
BEGIN DATE
1969
END DATE
Ongoing
LOCATION
Watershed 6 is a 13.23 ha watershed extending from the weir at 560 m to the ridge at 790 m.
West bounding coordinate: -71.743462
East bounding coordinate: -71.735649
North bounding coordinate: 43.957001
South bounding coordinate: 43.949928
East bounding coordinate: -71.735649
North bounding coordinate: 43.957001
South bounding coordinate: 43.949928
Elevation
Minimum: 560
Maximum: 790
(Unit: meter)
Maximum: 790
(Unit: meter)
SAMPLING BACKGROUND
The forest floor was first sampled in 1969-70. Hydrology has been monitored since 1963, and stream water chemistry has been monitored since 1963. The watershed is forested by typical northern hardwood species (sugar maple, beech and yellow birch) on the lower 90 % of its area and by a montane boreal transition forest of red spruce, balsam fir and white birch on the highest 10%. Surveying techniques were used in 1965 to install a grid system of 208 grid cells, each 25 x 25 m square. These grid units serve as the coordinate system for sample plot selection. For more spatial information please visit the following links: http://www.hubbardbrook.org/watersheds/maps/w6_zones.htm and http://www.hubbardbrook.org/watersheds/w6_grid_elevations.htm.
Sampling was initiated in 1969-1970, repeated in 1976, 1977, 1978, 1982 and at 5 year intervals after that. These data were collected in the summer of 1976. Repeated sampling at 5 year intervals is anticipated to continue.
SAMPLING DESIGN
Sampling was initiated in 1969-1970, repeated in 1976, 1977, 1978, 1982 and at 5 year intervals after that. These data were collected in the summer of 1976. Repeated sampling at 5 year intervals is anticipated to continue.
Each row of the Watershed 6 grid system of 25 x 25 m cells was considered a stratified sampling set and one or more cells was randomly chosen from these lines as cells to be sampled. Some rows are short, with only 1 to 4 cells, and others are longer, up to 10 cells across. The longer rows may have 2 or 3 cells sampled. The short rows may not have any cells sampled. The location of the sampling plot within each cell was selected by an x-y random number system and the location determined by pacing in to the selected coordinates from the corner of the 25 x 25 m cell. 59 of the 208 cells were sampled in 1976.
FIELD COLLECTION PROCEDURES
Once a sampling point was located by pacing, a 12" x 12" plywood board with a 15 x 15 cm square hole was placed on the forest floor and 4 nails were placed through pre-drilled holes, one on each corner. This served to hold the template in place on the forest floor. A keyhole saw was used to cut around the edge of the 15 x15 cm hole in the board. The forest floor within the hole was isolated and removed down to the mineral soil. The contents of the hole were then placed in total in a plastic bag for return to the laboratory. (Note that in some years the forest floor was divided into sub layers --Oi, Oe, Oa or combinations of these. In 1976 the whole of the forest floor was collected undivided).
This method made it difficult to see what was being removed, so it was modified in subsequent years. After 1976, a 15 x 15 cm wooden template was secured to the forest floor and a keyhole saw was used to cut around the outside of the template. The surrounding forest floor material was then scraped back from the block leaving it as a pedestal so that the horizons were easier to distinguish before removal.
NOTES
This method made it difficult to see what was being removed, so it was modified in subsequent years. After 1976, a 15 x 15 cm wooden template was secured to the forest floor and a keyhole saw was used to cut around the outside of the template. The surrounding forest floor material was then scraped back from the block leaving it as a pedestal so that the horizons were easier to distinguish before removal.
The primary objectives of the forest floor samplings in 1976-1978 were 1) the determination of the amount of lead(Pb) in the forest floor, 2) monitoring the total mass of the forest floor over time and 3) development of a field collection methodology which was efficient and easily implemented. It was determined that separation of the forest floor at least into Oie and Oa, would have been better than no separation whatsoever, so this procedure was implemented from 1987 onwards. It was also determined that air drying the Oa would have been preferable to oven drying. Air drying makes possible the determination of exchangeable nutrients, whereas oven drying alters the cation exchange complex. Air drying of the Oa was implemented from 1992 onwards.
LABORATORY PROCEDURES
The forest floor mass was oven dried at 80 oC to a constant weight, then ground in a Wiley mill to pass a 2 mm screen. Material too big or too tough (big sticks, roots, and rocks) to be put in the Wiley mill was removed. Samples of the ground forest floor were put in 4 oz. glass jars for long term preservation in the Hubbard Brook archives.
For determination of organic content and chemical analysis, a 2.0 g sample of the oven dry ground material was placed in a pre-weighed crucible and ashed overnight at 450 oC. The ashed material was cooled and weighed. The ash was eluted with 10 ml of 6N HNO3 and heated for a few minutes (to a simmer) on a hot plate. The hot extract solution was poured into a filter paper in a funnel and into a 50 ml volumetric flask. The crucible and the material on the filter paper were rinsed several times with distilled deionized water. Following these several rinsing, the volume in the flask was brought up to 50 ml with the distilled deionized water. The 50 ml of extract solution was then placed in 120 ml plastic bottles for storage until chemical analysis. The elements Zn, Pb and Cu were determined for each sample using an AA spectrophotometer.
In 1995, a 0.5 g sample of oven dry ground material from each jar was ashed and eluted by the method described above. The elements Ca and Mg were determined for each sample using an ICP spectrometer. Carbon and nitrogen were determined using oven dried ground material on a CHN analyzer- C and N data are not yet available. These elements are being analyzed by Steve Hamburg at Brown University.
CALCULATIONS
For determination of organic content and chemical analysis, a 2.0 g sample of the oven dry ground material was placed in a pre-weighed crucible and ashed overnight at 450 oC. The ashed material was cooled and weighed. The ash was eluted with 10 ml of 6N HNO3 and heated for a few minutes (to a simmer) on a hot plate. The hot extract solution was poured into a filter paper in a funnel and into a 50 ml volumetric flask. The crucible and the material on the filter paper were rinsed several times with distilled deionized water. Following these several rinsing, the volume in the flask was brought up to 50 ml with the distilled deionized water. The 50 ml of extract solution was then placed in 120 ml plastic bottles for storage until chemical analysis. The elements Zn, Pb and Cu were determined for each sample using an AA spectrophotometer.
In 1995, a 0.5 g sample of oven dry ground material from each jar was ashed and eluted by the method described above. The elements Ca and Mg were determined for each sample using an ICP spectrometer. Carbon and nitrogen were determined using oven dried ground material on a CHN analyzer- C and N data are not yet available. These elements are being analyzed by Steve Hamburg at Brown University.
Concentrations of elements in the forest floor were calculated on an oven dry weight basis. Total amounts of the elements were estimated on a per square meter basis by extrapolating up from the 15 x 15 cm sample mass. Total mass, organic matter mass, LOI , and concentrations and amounts of Cu, Pb, and Zn (1976 analysis) are presented in dataTable 1. Concentrations and amounts of Ca and Mg (1995 analysis) are presented in dataTable 2.
DATA ACCESS GUIDELINES
Publications using these data from the Hubbard Brook Ecosystem Study must include the following paragraph: Some data used in this publication were obtained by scientists of the Hubbard Brook Ecosystem Study; this publication has not been reviewed by those scientists. The Hubbard Brook Experimental Forest is operated and maintained by the Northeastern Research Station, U.S. Department of Agriculture, Newtown Square, Pennsylvania. Please note that data sharing and availability policy varies among the datasets available. Publishers of Hubbard Brook data are encouraged to contact the original data provider to obtain information for an acknowledgement of the original funding source of the research.
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By viewing or downloading the data, I certify that I accept the conditions herein
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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.
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party designated in the accompanying metadata of the Data Set as the primary contact for the Data Set.
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.
NOTES ON DATA
Original field data sheets are in Greeley Lab, 370 Prospect Street, Yale School of Forestry and Environmental Studies. Samples of forest floor material in jars will be located in the USFS archive building at the HBEF in Woodstock, NH.
CONTACT PERSON
Thomas G.
Siccama
Yale School of Forestry and Environmental Studies
New Haven, CT 06511
Phone: (203)-432-5140
Email: tgs3@pantheon.yale.edu
Yale School of Forestry and Environmental Studies
New Haven, CT 06511
Phone: (203)-432-5140
Email: tgs3@pantheon.yale.edu
Data file:
w676ffa.txt
Description: Hubbard Brook Forest Floor Data - Watershed 6 1976 - 59 15x15 cm excavated blocks Element amounts
CODES
Description: Hubbard Brook Forest Floor Data - Watershed 6 1976 - 59 15x15 cm excavated blocks Element amounts
| Column | Variable | Description | Units | Coded? | Missing value label |
| 1 | Plot | plots 1 to 208 from the top of the watershed to the base (not all plots were sampled) | none | y | none |
| 2 | Calcium (g/m2) | Calcium amount for forest floor in total (g/m2) | gramsPerSquareMeter | n | none |
| 3 | Magnesium (g/m2) | Magnesium amount for forest floor in total (g/m2) | gramsPerSquareMeter | n | none |
| 4 | Copper (g/m2) | Copper amount for forest floor in total (g/m2) | gramsPerSquareMeter | n | none |
| 5 | Zinc (g/m2) | Zinc amount for forest floor in total (g/m2) | gramsPerSquareMeter | n | none |
| 6 | Lead (g/m2) | Lead amount for forest floor in total (g/m2) | gramsPerSquareMeter | n | none |
Variable: Plot
|
Description:
|
A counting number representing an existent plot
|
Data file:
w676ffc.txt
Description: Hubbard Brook Forest Floor Data - Watershed 6 1976 - 59 15x15 cm excavated blocks Element concentrations
CODES
Description: Hubbard Brook Forest Floor Data - Watershed 6 1976 - 59 15x15 cm excavated blocks Element concentrations
| Column | Variable | Description | Units | Coded? | Missing value label |
| 1 | Plot | plots 1 to 208 from the top of the watershed to the base (not all plots were sampled) | none | y | none |
| 2 | Calcium (ppm) | Calcium concentration in sample (ppm) | number | n | none |
| 3 | Magnesium (ppm) | Magnesium concentration in sample (ppm) | number | n | none |
| 4 | Copper (ppm) | Copper concentration in sample (ppm) | number | n | none |
| 5 | Zinc (ppm) | Zinc concentration in sample (ppm) | number | n | none |
| 6 | Lead (ppm) | Lead concentration in sample (ppm) | number | n | none |
Variable: Plot
|
Description:
|
A counting number representing an existent plot
|
Data file:
w676ffm.txt
Description: Hubbard Brook Forest Floor Data - Watershed 6 1976 - 59 15x15 cm excavated blocks Mass data
CODES
Description: Hubbard Brook Forest Floor Data - Watershed 6 1976 - 59 15x15 cm excavated blocks Mass data
| Column | Variable | Description | Units | Coded? | Missing value label |
| 1 | Plot | plots 1 to 208 from the top of the watershed to the base (not all plots were sampled) | none | y | none |
| 2 | Total mass (kg/m2) | Oven dry wt of total mass of forest floor (kg/m2) | kilogramsPerSquareMeter | n | none |
| 3 | OM Mass (kg/m2) | Oven dry wt of organic matter mass of forest floor from 1976 analysis (kg/m2) | kilogramsPerSquareMeter | n | none |
| 4 | LOI % 1976 | Loss on Ignition of forest floor from 1976 analysis (%) | dimensionless | n | none |
| 5 | LOI % 1995 | Loss on Ignition of forest floor from 1995 analysis (%) | dimensionless | n | none |
Variable: Plot
|
Description:
|
A counting number representing an existent plot
|