NDP-061A

Effects of CO2 and Nitrogen Fertilization on Growth and Nutrient Content of Juvenile Ponderosa Pine



Contributed by

Dale W. Johnson,1,2 J. Timothy Ball,1 and Roger F. Walker2

1Biological Sciences Center
Desert Research Institute
P.O. Box 60220
Reno, NV 89506

2Environmental and Resource Sciences
College of Agriculture
University of Nevada
Reno, NV 89512






Prepared by Robert M. Cushman
Carbon Dioxide Information Analysis Center
Environmental Sciences Division
Publication No. 4754
Date Published: March 1998

Prepared for the
Environmental Sciences Division
Office of Biological and Environmental Research
Budget Activity Number KP 12 04 01 0

Prepared by the
Carbon Dioxide Information Analysis Center
OAK RIDGE NATIONAL LABORATORY
Oak Ridge, Tennessee 37831-6335
managed by
LOCKHEED MARTIN ENERGY RESEARCH CORP.
for the
U.S. DEPARTMENT OF ENERGY
under contract DE-AC05-96OR22464

CONTENTS


ABSTRACT

PART 1: INFORMATION ABOUT THE DATA PACKAGE

1. NAME OF THE NUMERIC DATA PACKAGE
2. PRINCIPAL INVESTIGATORS
3. KEYWORDS
4. BACKGROUND INFORMATION
5. EXPERIMENTAL SETUP AND METHODS
6. APPLICATIONS OF THE DATA
7. DATA LIMITATIONS AND RESTRICTIONS
8. REFERENCES
9. QUALITY-ASSURANCE CHECKS AND DATA-PROCESSING ACTIVITIES PERFORMED BY CDIAC
10. HOW TO OBTAIN THE DATA AND DOCUMENTATION

PART 2: CONTENT AND FORMAT OF DATA FILES

11. LISTING OF FILES PROVIDED
12. DESCRIPTION OF THE DOCUMENTATION FILE
13. DESCRIPTION OF THE DATA FILES
14. LISTING OF THE FORTRAN DATA RETRIEVAL PROGRAMS
15. LISTING OF THE SAS DATA RETRIEVAL PROGRAMS
16. PARTIAL LISTINGS OF THE FLAT ASCII DATA FILES

ABSTRACT

JOHNSON, D. W., J. T. BALL, AND R. F. WALKER. 1998. Effects of CO2 and Nitrogen Fertilization on Growth and Nutrient Content of Juvenile Ponderosa Pine. ORNL/CDIAC-107, NDP-061A, Carbon Dioxide Information Analysis Center, Oak Ridge National Laboratory, U.S. Department of Energy, Oak Ridge, Tennessee.

This data set presents measured values of plant diameter and height, biomass of plant components, and nutrient (carbon, nitrogen, phosphorus, sulfur, potassium, calcium, magnesium, boron, copper, iron, manganese, and zinc) concentrations from a study of the effects of carbon dioxide and nitrogen fertilization on ponderosa pine (Pinus ponderosa Dougl. ex Laws.) conducted in open-top chambers in Placerville, California, from 1991 through 1996. This data set contains values from 1991 through 1993.

PART 1: INFORMATION ABOUT THE DATA PACKAGE

1. NAME OF THE NUMERIC DATA PACKAGE

EFFECTS OF CO2 AND NITROGEN FERTILIZATION ON GROWTH AND NUTRIENT CONTENT OF JUVENILE PONDEROSA PINE


2. PRINCIPAL INVESTIGATORS

Dale W. Johnson,1,2 J. Timothy Ball,1 and Roger F. Walker2

1Biological Sciences Center
Desert Research Institute
P.O. Box 60220
Reno, NV 89506

2Environmental and Resource Sciences
College of Agriculture
University of Nevada
Reno, NV 89512


3. KEYWORDS

Boron, calcium, carbon, carbon dioxide fertilization, copper, growth, iron, magnesium, manganese, nitrogen, nitrogen fertilization, nutrients, phosphorus, ponderosa pine, potassium, sulfur, zinc


4. BACKGROUND INFORMATION

This data set presents measured values of plant diameter and height, biomass of plant components, and nutrients in vegetation from a study of the effects of carbon dioxide and nitrogen fertilization on ponderosa pine (Pinus ponderosa Dougl. ex. Laws.) conducted in open-top chambers in Placerville, California, from 1991 through 1996. This data set contains values from 1991 through 1993. Further background for the study, as well as the results and conclusions from the study, may be found in Johnson et al. (1997), which is the primary reference for this data set. Users who wish to use these data in specific model exercises or research exercises should first refer to Johnson et al. (1997).


5. EXPERIMENTAL SETUP AND METHODS

Detailed information concerning the site and experimental setup, treatments, and sampling and analytical methods is given in Johnson et al. (1997) and Walker et al. (1997); the methods are summarized below.

Twenty-four hexagonal open-top chambers, 3.6 m in diameter, were established in February April 1991 at the Institute of Forest Genetics in Placerville, California, on a soil of Aiken clay loam, an andesite-derived Xeric Haplohumult. The studied pines were grown from seeds (21 locations per chamber) planted in May 1991.

Treatment began in May 1991. There were three treatment levels of nitrogen (N) fertilization (0, 10, and 20 g N per square meter per year applied as ammonium sulfate) and four CO2 treatments (ambient, no chamber; ambient, chambered; 525 microliters CO2 per liter air; and 700 microliters CO2 per liter air). All combinations of the treatments were studied, except for the combination of 10 g N per square meter per year and 525 microliters CO2 per liter air. Each of the unchambered treatments was replicated twice, each of the chambered treatments thrice. All plots were watered identically.

Three trees from each chamber were harvested in October 1991, 1992, and 1993 (including complete root systems for all three harvested trees per chamber in 1991 and 1992 and for one tree per chamber in 1993). Seedlings were dried, weighed by component (foliage, branch, stem, and roots; in 1991 and 1992, branches were sufficiently trivial that their weights were included with those of stems), and analyzed as follows:

N: analyzed on a Perkin-Elmer 2400 CHN Analyzer

Other nutrients (P, S, K, Ca, Mg, B, Cu, Fe, Mn, Zn): dry-ashed at 550 degrees Celsius for 4 h, dissolved in 5% (v/v) nitric acid, and analyzed by inductively-coupled plasma (ICP) emission spectroscopy

In 1992, no elemental analyses were conducted for branches in the unchambered treatment.

Tree biomass for needles, stems (including branches), and roots was measured directly in 1991 for the trees analyzed for nutrient concentration. For 1992 and 1993, the following regression was established (based on measured diameters, heights, and biomass), relating biomass in grams for each component (Comp) to diameter (d), measured in mm at 10 cm, and height (h), measured in cm:

ln(Comp) = a + (b)ln(d2h), where a and b are regression constants given in the following table: 

_____________________________________________________________

Component         a              b             r2
_____________________________________________________________

                          1992 Harvest

Needles        -2.9797        0.65540        0.692

Stems +
branches       -4.8812        0.86967        0.724

Roots          -4.9412        0.84429        0.615


                          1993 Harvest

Needles        -6.2504        1.0395         0.729

Branches      -12.173         1.4685         0.631

Stems          -9.4724        1.3200         0.819

Roots          -6.7686        1.038          0.868
______________________________________________________________
Measurements in 1993 were based on one whole tree, plus two additional tree tops, harvested per chamber. The user should note that two sets of height and diameter data are reported for 1993 (in association with the measured nutrient concentration data, and in association with the biomass data used to generate the regressions); the height and diameter measurements used to generate the regressions were taken a short time after the measurements at harvest.

In the data files and this documentation, the terms "leaf" and "needle" are equivalents, as are "stem" and "trunk."

6. APPLICATIONS OF THE DATA

These data may be used to study the effect of elevated levels of atmospheric carbon dioxide, in combination with various levels of nitrogen fertilization, on the growth and nutrient content of ponderosa pine (Pinus ponderosa Dougl. ex Laws.), an important timber species of western North America. Johnson et al. (1997) used the data documented in this numeric data package to evaluate two hypotheses: (1) that elevated CO2 would increase growth and yield of biomass per unit uptake of N even if N is limiting, and (2) that elevated CO2 would increase biomass yield per unit uptake of other, nonlimiting nutrients only by growth dilution.

For several years, research has been conducted on the effects of elevated carbon dioxide, alone or in combination with other factors such as the availability of water and nutrients, on many different wild and cultivated plant species. There has been a trend towards more realistic conditions: from flowerpot studies in growth chambers to open-top chamber studies (the experiment whose data are documented in this numeric data package is one such study), in which the plants are exposed to the atmosphere and in which the roots are not necessarily confined to pots. A further step towards realism was taken in the 1990s with the development of the FACE (Free Air CO2 Enrichment) studies (Ellsworth et al. 1995), in which plants are grown without confinement in chambers and carbon dioxide is typically released around the perimeter of the circular study area (with attention paid to wind speed and direction) in sufficient quantity to maintain desired concentrations of carbon dioxide within the study area.

An early review of the literature on the effects of elevated carbon dioxide on vegetation may be found in Strain and Cure (1985), while a recent review may be found in Amthor (1995). Two bibliographies that include much of the pertinent literature are Strain and Cure (1986) and Strain and Cure (1994). Curtis (1997) is an on-line data base that summarizes many studies of the effects of elevated carbon dioxide on woody vegetation.


7. DATA LIMITATIONS AND RESTRICTIONS

Users should appreciate that the study whose data are documented in this numeric data package suffers from the inherent limitation common to all open-top chambers studies: the plants are confined in chambers and therefore are not growing in completely natural conditions. For a critique of open-top chamber studies, and descriptions of other experimental approaches for measuring the responses of plants to elevated carbon dioxide, the user is referred to Allen et al. (1992) and Ceulemans and Mousseau (1994).

Johnson et al. (1997) have noted that observed declines in soil carbon and nitrogen during the study probably resulted from plowing that occurred before planting, rather than from the experimental treatment. It is possible that some observed changes in plant growth and nutrient content may also have been responses to plowing, rather than to the experimental treatment. That is, preplanting plowing may be considered a potential artifact of the experiment.

Users are cautioned against using sample tree averages to estimate treatment effects because that would yield a biased result; that is, the sample trees did not reflect the average dimensions of all trees in the chambers. An unbiased estimate of biomass and nutrient content can be obtained by applying regressions to the diameter and height measurements of all trees in the chambers.


8. REFERENCES

Allen, L.H., Jr., B.G. Drake, H.H. Rogers, and J.H. Shinn. 1992. Field techniques for exposure of plants and ecosystems to elevated CO2 and other trace gases. Critical Reviews in Plant Sciences 11:85-119.

Amthor, J.S. 1995. Terrestrial higher-plant response to increasing atmospheric [CO2] in relation to the global carbon cycle. Global Change Biology 1:243-274.

Ceulemans, R., and M. Mousseau. 1994. Effects of elevated atmospheric CO2 on woody plants (Tansley Review No. 71). New Phytologist 127:425-446.

Curtis, P.S. 1997. A Comprehensive Database of Woody Vegetation Responses to Elevated Atmospheric CO2. Carbon Dioxide Information Analysis Center, Oak Ridge National Laboratory, U.S. Department of Energy.

Ellsworth, D.S., R. Orem, C. Huang, N. Phillips, and G.R. Hendrey. 1995. Leaf and canopy responses to elevated CO2 in a pine forest under free-air CO2 enrichment. Oecologia 104:139-146.

Johnson, D.W., J.T. Ball, and R.F. Walker, 1997. Effects of CO2 and nitrogen fertilization on vegetation and soil nutrient content in juvenile ponderosa pine. Plant and Soil 190:29-40.

Strain, B.R., and J.D. Cure (eds.). 1985. Direct effects of increasing carbon dioxide on vegetation. DOE/ER-0238. U.S. Department of Energy, Washington, D.C.

Strain, B.R., and J.D. Cure. 1986. Direct effects of atmospheric CO2 enrichment on plants and ecosystems: A bibliography with abstracts. ORNL/CDIC-13. Carbon Dioxide Information Analysis Center, Oak Ridge National Laboratory, U.S. Department of Energy.

Strain, B.R., and J.D. Cure. 1994. Direct effects of atmospheric CO2 enrichment on plants and ecosystems: An updated bibliographic data base. ORNL/CDIAC-70. Carbon Dioxide Information Analysis Center, Oak Ridge National Laboratory, U.S. Department of Energy.

Walker, R.F., D.R. Geisinger, D.W. Johnson, and J.T. Ball, 1997. Elevated atmospheric CO2 and soil N fertility effects on growth, mycorrhizal colonization, and xylem water potential of juvenile ponderosa pine in a field soil. Plant and Soil 195:25-36.


9. QUALITY-ASSURANCE CHECKS AND DATA-PROCESSING ACTIVITIES PERFORMED BY CDIAC

An important part of the data-packaging process at the Carbon Dioxide Information Analysis Center (CDIAC) is the quality assurance (QA) of the data before their distribution. The QA process is an important component in the value-added concept of ensuring accurate, usable information. The complete QA of a data set can be a time-consuming process, since data received by CDIAC are rarely in condition for immediate distribution, regardless of source. The following summarizes the QA checks and data-processing performed on the data sets presented in this document:

1. The EXCEL (registered trademark of the Microsoft Corporation, Redmond, Washington) spreadsheet files were provided by the principal investigators.

2. Cell formulas contained in the spreadsheets received by CDIAC were checked for correctness using EXCEL and QUATTRO PRO (registered trademark of the Corel Corporation, Ottawa, Ontario, Canada).

3. Values entered directly into the spreadsheets were verified wherever possible by values calculated from data already in the spreadsheets.

4. The files were simplified and reduced to include only direct measurements (of diameter, height, biomass, and nutrient concentrations); estimated values (e.g., biomass calculated from regressions, nutrient content derived from estimated biomass and measured concentration) and statistics were removed.

5. The files for the 1992 and 1993 data were compared with respect to carbon dioxide and nitrogen treatment levels, chamber label, and replicate number, to ensure correctness and consistency of nomenclature.

6. Variables were renamed for internal consistency, with the new names ranging from one to six characters each.

7. Spreadsheet files were reformatted into 1-2-3 (registered trademark of the Lotus Development Corporation, Cambridge, Massachusetts) *.wk1 spreadsheet files and converted into flat ASCII files, in which -9, -9.9, or -9.99 represent missing values.


10. HOW TO OBTAIN THE DATA AND DOCUMENTATION

These data may be used with spreadsheet software (e.g., 1-2-3, EXCEL, or QUATTRO PRO) or with other database management and statistical software. The spreadsheets in this data package were saved as both 1-2-3 *.wk1 spreadsheet files and *.dat flat ASCII files. The computerized data are available on Exabyte 8-mm tapes, QIC 1/4" tape cartridges, IBM DOS-compatible floppy diskettes (3.5" or 5.25"), and through CDIAC's World Wide Web site and anonymous File Transfer Protocol (FTP) area (addresses given below). Requests for magnetic media should include any specific instructions required by the user and/or the user's local computer system. Requests for this package should be addressed to:

Carbon Dioxide Information Analysis Center
Oak Ridge National Laboratory
Oak Ridge, TN 37831-6335
U.S.A.

Telephone: (865) 574-3645
Fax: (865) 574-2232
Email: cdiac@ornl.gov

FTP: cdiac.esd.ornl.gov
URL: http://cdiac.esd.ornl.gov

The data files may be acquired via Internet from CDIAC's anonymous FTP service as follows:




PART 2: CONTENT AND FORMAT OF DATA FILES

11. LISTING OF FILES PROVIDED

The following table lists the files distributed by CDIAC along with this documentation.

Table 1. List and description of the digital files
______________________________________________________________________________

File
number          Name                  Description               File size (kB)
______________________________________________________________________________

  1          ndp061a.txt        ASCII descriptive                   90
                                information file

  2          regr92.dat         1992 height, diameter,               5
                                and biomass data

  3          regr93.dat         1993 height, diameter,               5 
                                and biomass data 

  4          trees91.dat        1991 biomass and                     9 
                                nutrient data

  5          trees92.dat        1992 height, diameter,              15
                                and nutrient data

  6          trees93.dat        1993 height, diameter,             262
                                and nutrient data
 
  7          regr92.wk1         spreadsheet file corresponding      14
                                to gr92.dat (File 2)

  8          regr93.wk1         spreadsheet file corresponding      16 
                                to regr93.dat (File 3)

  9          trees91.wk1        spreadsheet file corresponding      27 
                                to trees91.dat (File 4)

 10          trees92.wk1        spreadsheet file corresponding      35
                                to trees92.dat (File 5)

 11          trees93.wk1        spreadsheet file corresponding     400
                                to trees93.dat (File 6)

 12          regr92.for         FORTRAN 77 data retrieval            1
                                routine to read regr92.dat 
                                (File 2)

 13          regr93.for         FORTRAN 77 data retrieval            1
                                routine to read regr93.dat 
                                (File 3)
  
 14          trees91.for        FORTRAN 77 data retrieval            1
                                routine to read trees91.dat
                                (File 4)
  
 15          trees92.for        FORTRAN 77 data retrieval            2
                                routine to read trees92.dat 
                                (File 5)
  
 16          trees93.for        FORTRAN 77 data retrieval            3
                                routine to read trees93.dat 
                                (File 6)
 
 17          regr92.sas         SAS data retrieval routine           1
                                to read regr92.dat (File 2)

 18          regr93.sas         SAS data retrieval routine           1
                                read regr93.dat (File 3)

 19          trees91.sas        SAS data retrieval routine           1
                                to read trees91.dat (File 4)

 20          trees92.sas        SAS data retrieval routine           1
                                to read trees92.dat (File 5)

 21          trees93.sas        SAS data retrieval routine           2
                                to read trees93.dat (File 6)

______________________________________________________________________________



12. DESCRIPTION OF THE DOCUMENTATION FILE

ndp061a.txt (File 1)

This file contains a detailed description of the data base (name of the numeric data package, principal investigators, keywords, background information, experimental setup and methods, applications of the data, data limitations and restrictions, references, QA checks and data-processing activities performed by CDIAC) and how to obtain the data and documentation. A description of the formats, units, and other pertinent information about each file associated with this database is included.


13. DESCRIPTION OF THE DATA FILES

DATA FORMAT AND UNITS

The data contained in this NDP are available as both 1-2-3 spreadsheet files and flat ASCII files. SAS and FORTRAN programs designed to read each ASCII data file are also provided.

In all files, C (carbon dioxide treatment) is defined as follows:

1 = no chamber;
2 = ambient (350 microliters CO2 per liter air);
3 = 525 microliters CO2 per liter air;
4 = 700 microliters CO2 per liter air.

N (nitrogen treatment) is defined as follows:

1 = unfertilized;
2 = 10 g N per square meter per year;
3 = 20 g N per square meter per year.

Each variable label consists of up to six characters, where

BM denotes biomass,
BR denotes branch,
CC denotes a concentration (mass per unit mass) of a nutrient in plant tissue,
CD denotes candle (new shoots where needles have not come out yet),
CHBR denotes open-top chamber identification label,
CR denotes coarse root [the sum of medium root plus tap root (i.e., diameter >2 mm)],
DIA denotes diameter,
FO denotes foliage,
FR denotes fine root (diameter <2 mm),
HT denotes height,
LF denotes leaf (needle),
LR denotes lateral root,
MR denotes medium root (diameter from 2 mm to 1 cm),
N1 denotes first-flush needle (the first flush of needles in a given year),
N2 denotes second-flush needle (the second flush of needles in a given year),
NO denotes old needle (needles that appeared before 1993),
NS denotes senesced needle (brown needles that were about ready to fall off the tree),
REP denotes seedling replicate identification label,
RT denotes root,
ST denotes stem (includes branches in 1991 and 1992),
TB denotes trunk bottom (10 cm from the bottom of the trunk),
TM denotes trunk middle (halfway up the trunk),
TR denotes tap root,
TT denotes trunk top (the middle of the top shoot),

and where the standard chemical symbol (in all upper case) is used for elements. The general pattern for indicating nutrient concentrations (i.e., the final two letters are "CC") is that the first two letters indicate the plant tissue, and the following one or two letters indicate the nutrient; thus, "LFMNCC" represents the measured concentration of manganese in leaf tissue.


FLAT ASCII DATA FILES

The following tables describe the contents and formats of the five flat ASCII files that are distributed with this data package. Missing values are represented by -9.99, with two exceptions: -9 represents missing values of REP in trees91.dat (File 4), and -9.9 represents missing values of HT in regr93.dat (File 3). The data files in this package do not contain any negative values other than the missing-value indicators. The following tables also indicate the column in the corresponding spreadsheet files in which each variable is found. For trees92.dat (File 5), the user should note that, for the sake of consistency of format, all data in columns >35 are shown with an apparent precision of two digits to the right of the decimal (i.e., hundredths of the specified unit); for trees93.dat (File 6), this applies to all data in columns >42. This should not be construed as the true precision of measurement; for many variables the user will observe only zeros to the right of the decimal (other than in the case of -9.99, the missing-value indicator).

The user is strongly urged to pay careful attention to the variable widths specified in the following tables and in the FORTRAN and SAS data retrieval programs provided with this package (*.for and *.sas, respectively). In some cases (i.e., where values occupy all the allotted six or seven spaces), adjacent values will run together, and there will be no space between adjacent values. Therefore, importing the data into a program with space or tab delimiters would produce erroneous results. It is highly recommended that the *.wk1files provided with this data package be used for spreadsheet applications.

1-2-3 SPREADSHEET FILES

Five 1-2-3 data files, from which the corresponding flat ASCII files described in the preceding section were generated, are also provided with this data package: