TITLE OF THE DATA SET

Carbon Dioxide Enrichment: Data on the Response of Cotton to
Varying CO2, Irrigation, and Nitrogen.

DATA CONTRIBUTORS

B. A. Kimball (1)    J. R. Mauney (2)       R. L. La Morte (1)
G. Guinn (2)         F. S. Nakayama (1)     J. W. Radin (2)
E. A. Lakatos (3)    S. T. Mitchell (1)     L. L. Parker (2)
G. J. Peresta (1)    P. E. Nixon III (1)    B. Savoy (2)
S. M. Harris (1)     R. MacDonald (2)       H. Pros (2)
J. Martinez (1)

(1) U.S. Water Conservation Laboratory  and  (2) Western Cotton
Research Laboratory
U.S. Department of Agriculture, Agricultural Research Service
Phoenix, Arizona

(3) Soil and Water Science Department
University of Arizona
Tucson, Arizona

SOURCE AND SCOPE OF THE DATA

     The data set included in this subdirectory ("pub/ndp037")       
details five season-long experiments, carried out over the period
1983-1987, examining the effects of CO2 enrichment on cotton
growth.  Because conditions of insufficient water and nutrients are
commonplace in much of the world's agriculture and in the unmanaged
biosphere, these studies employed a multivariate design whereby the
effects of water and nutrient stress could be examined alongside
the effects of elevated CO2 level on plant growth parameters.  The
initial experiment examined the effects of varying CO2
concentration only.  In the following two seasons, the interactive
effects of CO2 concentration and water availability were studied. 
In the final two seasons, the effects of the three-way interaction
between CO2 concentration, water availability, and nitrogen
fertility were investigated.  The 1983 experiment was conducted on
the lysimeter field at the U.S. Water Conservation Laboratory,
Phoenix, Arizona.  The experiments during the four subsequent years
were conducted at a site near the Western Cotton Research
Laboratory, Phoenix, Arizona.  At each site, a system of open-top
chambers was constructed to provide a stable regime of CO2
enrichment through the course of a growing season.  A summary of
the preparations and treatments undertaken in each of the five
growing seasons is provided in Tables 2a-2d of the documentation that
accompanies this tape.  For detailed descriptions of the design and
methodology of these experiments, the reader should refer to the
supplemental text provided in the appendix of the accompanying
documentation.  Further information is also provided in Kimball et
al. (1983, 1984, 1985, 1986, 1987).  
     The data comprise three types of information: identification
variables (such as year, institution and site codes, and treatment
regimens), intermediate growth measurements (such as plant height,
leaf area index, number of flowers, and dry weight of leaves) taken
at various times during the growing season, and crop harvest
results (such as lint yield, seed yield, and total aboveground dry
biomass).  The data selected for inclusion in the "pub/ndp037"  
subdirectory are those that are likely to be useful to the largest 
number of users.  Data are also available for many other parameters, 
including daily weather, soil profile properties (e.g., initial 
soil moisture and nitrogen conditions), and irrigation and
fertilizer treatments.  These highly specialized data comprise a
very large number of separate files.  The file structures of these
data conform to the International Benchmark Sites of Agrotechnology
Transfer (IBSNAT) standards, developed in 1986 by plant growth 
modelers for crop model input and output files (IBSNAT 1986).  The
IBSNAT-formatted data files, along with a documentation file 
("IBSNAT.txt"), are provided in the subdirectory "pub/ndp037/IBSNAT". 
Persons wishing to use the IBSNAT-formatted data are also advised to
consult the supplemental file "suppl.wp" provided in this subdirectory
("pub/ndp037").  The file "suppl.wp" is formatted as a Word Perfect
file and will require WP 5.1 software for access.  Because the file
is not formatted as a standard DOS ASCII text, FTP users should copy
the file in the "binary" transfer mode.  The information provided in
"suppl.wp" is also included as part of the written documentation for
NDP-037 and is available upon request from CDIAC.  This documentation 
also presents all of the IBSNAT-formatted data in hard copy form.
     Measurements of plant physiological parameters, such as leaf
temperature, stomatal resistance, and leaf water potential, are not
available from CDIAC at this time.  However, these data are
discussed in Kimball et al. (1983, 1984, 1985, 1986, 1987).

DATA FORMAT

     Five files are provided in this subdirectory ("pub/ndp037")
including this documentation file ("ndp037.txt"), a FORTRAN IV retrieval
program ("ndp037.for"), a SAS input/output routine ("ndp037.sas"), a
file containing the CO2 enrichment response data ("ndp037.dat"), and
a supplemental information file ("suppl.wp"), formatted in Word Perfect
5.1.
     Table 4 (located in the written documentation that accompanies
these data) presents a partial listing of the CO2 enrichment response
data.  The data file is formatted in the following way:

      INTEGER YEAR, CO2, REP, YRCODE, EXPTNO, TRTNO, JEMRGD,
     1  JSQRJD, JFLRJD, XLTYLD, XSDYLD, XBLSM, XSPB, XBIOM,
     2  XSTMBR, JDOY, XPLTHT, JNNODM, JNSQRM, JNFLWM, JNGBLM,
     3  JNMBLM, JNABSM, XWLEFH, XWSTMH, XWROTH, XWGBLH, XWMBLH
      CHARACTER CO2COD, IRRIG, NITRO, INSTE*2, SITEE*2, DUMMY*3
      REAL XLAI, XSDWT, XLAIMX
   10 READ (5,400,END=900) YEAR, CO2, CO2COD, REP, IRRIG, NITRO
      READ (5,500) INSTE, SITEE, YRCODE, EXPTNO, TRTNO, JEMRGD,
     1  JSQRJD, JFLRJD, XLTYLD, XSDYLD, XSDWT, XBLSM, XSPB,
     2  XLAIMX, XBIOM, XSTMBR
   20 READ (5,600) DUMMY 
      IF (DUMMY.EQ.'   ') THEN
        GOTO 10
      ELSE
        BACKSPACE (5)
        READ (5,800) JDOY, XPLTHT, XLAI, JNNODM, JNSQRM, JNFLWM,
     1    JNGBLM, JNMBLM, JNABSM, XWLEFH, XWSTMH, XWROTH, XWGBLH,
     2    XWMBLH
        GOTO 20
      END IF
  400 FORMAT (1X,I4,2X,I3,2X,A1,2X,I1,2X,A1,2X,A1)
  500 FORMAT (1X,A2,A2,I2,I2,1X,I2,1X,I3,1X,I3,1X,I3,1X,
     1        I4,1X,I4,1X,F6.4,1X,I3,1X,I2,1X,F5.2,1X,I5,1X,I4)
  600 FORMAT (1X,A3)
  800 FORMAT (1X,I3,1X,I3,1X,F5.2,1X,I3,1X,I3,1X,I3,1X,I3,
     1        1X,I3,1X,I4,1X,I4,1X,I4,1X,I4,1X,I4,1X,I5)

where

YEAR               is the year of sampling of the data record being
                   read;

CO2                is the mean daily carbon dioxide concentration
                   (umol/mol) for the sampled plot;

CO2COD             is a one-character flag code presenting
                   additional information about the sampled plot:
                   'A'= chamber at ambient (i.e., nonenriched)
                   concentration, 'N'= no chamber (i.e., open field),
                   and 'L'= chamber containing lysimeter;

REP                is the replicate number, with a value of either
                   '1' or '2' (two replicates were included for
                   each CO2 treatment);

IRRIG              is a one-character code describing the
                   irrigation regimen, given only for years in which
                   two levels were present: '0'= water-stressed ("dry")
                   treatment and '1'= well-watered ("wet") treatment;

NITRO              is a one-character code describing the nitrogen
                   fertilization regimen, given only for years in
                   which two levels were present: '0'= low nitrogen (N-)
                   treatment and '1'= high nitrogen (N+) treatment;

INSTE              is a two-character identification code
                   describing the institution at which the cotton
                   growth experiment was carried out; this code conforms
                   to the IBSNAT format described on pages A-64, A-89,
                   and A-90 of the accompanying documentation;

SITEE              is a two-character identification code describing
                   the location of the sampled plot and the
                   experimental treatment; diagrams of the plot
                   locations and listings of the corresponding
                   treatments are given on pages A-19, A-22, and A-26
                   of the accompanying documentation;

YRCODE             is the last two digits of YEAR; this code is the
                   same as the variable YEAR in the IBSNAT format
                   described on pages A-71, A-89, and A-90 of the
                   accompanying documentation;

EXPTNO             is the experiment number, which conforms to the
                   IBSNAT format described on pages A-63, A-89,
                   and A-90 of the accompanying documentation;

TRTNO              is the treatment number, which conforms to the
                   IBSNAT format described on pages A-69, A-89,
                   and A-90 of the accompanying documentation;

JEMRGD             is the day of year (Julian) at which 50% of the
                   plants in the field emerge from the soil;

JSQRJD             is the day of year (Julian) at which 50% of the
                   plants in the field displayed their first
                   square;

JFLRJD             is the day of year (Julian) at which 50% of the
                   plants in the field displayed their first
                   flower;

XLTYLD             is the actual field-measured lint yield (dry
                   weight basis, kg/ha), which is the yield
                   attainable by hand harvesting;

XSDYLD             is the actual field-measured seed yield (dry
                   weight basis, kg/ha);

XSDWT              is the measured seed dry weight (g/seed);

XBLSM              is the field-measured boll number (bolls/square
                   meter);

XSPB               is the field-measured number of seeds per boll;

XLAIMX             is the maximum leaf area index attained during
                   the season (square meters/square meters);

XBIOM              is the field-measured aboveground dry biomass at
                   maturity (kg/ha);

XSTMBR             is the field-measured stem plus burr weight at
                   maturity (kg/ha);

JDOY               is the day of year (Julian) on which the
                   intermediate growth measurements on the
                   remainder of the line were made;

XPLTHT             is the plant height (cm);

XLAI               is the leaf area index (square meters/
                   square meters);

JNNODM             is the number of nodes per square meter;

JNSQRM             is the number of squares per square meter;

JNFLWM             is the number of flowers per square meter;

JNGBLM             is the number of green bolls per square meter;

JNMBLM             is the number of open mature bolls per square
                   meter;

JNABSM             is the number of abscised sites per square
                   meter;

XWLEFH             is the dry leaf weight (kg/ha);

XWSTMH             is the dry stem weight (kg/ha);

XWROTH             is the dry root weight (kg/ha);

XWGBLH             is the dry green boll weight (kg/ha);

XWMBLH             is the dry mature boll weight (kg/ha);

Stated in tabular form, the contents include the following.

__________________________________________________________________
            Variable    Variable              Starting    Starting
Variable      type       width       Line      column      column
__________________________________________________________________
YEAR         Numeric       I4          1          2           5
CO2          Numeric       I3          1          8          10
CO2COD      Character      A1          1         13          13
REP          Numeric       I1          1         16          16
IRRIG       Character      A1          1         19          19
NITRO       Character      A1          1         22          22
INSTE       Character      A2          2          2           3
SITEE       Character      A2          2          4           5
YRCODE       Numeric       I2          2          6           7
EXPTNO       Numeric       I2          2          8           9
TRTNO        Numeric       I2          2         11          12
JEMRGD       Numeric       I3          2         14          16
JSQRJD       Numeric       I3          2         18          20
JFLRJD       Numeric       I3          2         22          24
XLTYLD       Numeric       I4          2         26          29
XSDYLD       Numeric       I4          2         31          34
XSDWT        Numeric      F6.4         2         36          41
XBLSM        Numeric       I3          2         43          45
XSPB         Numeric       I2          2         47          48
XLAIMX       Numeric      F5.2         2         50          54
XBIOM        Numeric       I5          2         56          60
XSTMBR       Numeric       I4          2         62          65
JDOY         Numeric       I3        3...n        2           4
XPLTHT       Numeric       I3        3...n        6           8
XLAI         Numeric      F5.2       3...n       10          14
JNNODM       Numeric       I3        3...n       16          18
JNSQRM       Numeric       I3        3...n       20          22
JNFLWM       Numeric       I3        3...n       24          26
JNGBLM       Numeric       I3        3...n       28          30
JNMBLM       Numeric       I3        3...n       32          34
JNABSM       Numeric       I4        3...n       36          39
XWLEFH       Numeric       I4        3...n       41          44
XWSTMH       Numeric       I4        3...n       46          49
XWROTH       Numeric       I4        3...n       51          54
XWGBLH       Numeric       I4        3...n       56          59
XWMBLH       Numeric       I5        3...n       61          65
__________________________________________________________________

Missing values for integer variables are represented by -9. 
Missing values for real variables are represented by -9.0,
-9.00, etc., according to the format of each variable.
Line numbers refer to positions within a given data block,
containing data for a given year, site, and treatment regimen.

REFERENCES

IBSNAT, the International Benchmark Sites Network for
     Agrotechnology Transfer.  1986.  IBSNAT Technical Report 5,
     Decision Support System for Agrotechnology Transfer (DSSAT),
     Documentation for IBSNAT Crop Model Input and Output Files,
     Version 1.0.  Department of Agronomy and Soil Science,
     University of Hawaii, Honolulu.  53 pp.

Kimball, B. A., J. R. Mauney, G. Guinn, F. S. Nakayama, P. J. Pinter, Jr.,
     K. L. Clawson, R. J. Reginato, and S. B. Idso.  1983.  Effects of
     Increasing Atmospheric CO2 on the Yield and Water Use of Crops.
     No. 021, U.S. Department of Energy Series, Response of Vegetation
     to Carbon Dioxide.  Agricultural Research Service, U.S. Department
     of Agriculture, Washington, D.C.  37 pp.

Kimball, B. A., J. R. Mauney, G. Guinn, F. S. Nakayama, P. J. Pinter, Jr.,
     K. L. Clawson, S. B. Idso, G. D. Butler, Jr., and J. W. Radin.  1984.
     Effects of Increasing Atmospheric CO2 on the Yield  and Water Use of
     Crops.  No. 023, Response of Vegetation to Carbon Dioxide, U.S.
     Department of Energy, Carbon Dioxide Research Division, and the U.S.
     Department of Agriculture, Agricultural Research Service, Washington,
     D.C.  60 pp.

Kimball, B. A., J. R. Mauney, G. Guinn, F. S. Nakayama, S. B. Idso,
     J. W. Radin, D. L. Hendrix, G. D. Butler, Jr., T. I. Zarembinski,
     and P. E. Nixon, III.  1985.  Effects of Increasing Atmospheric
     CO2 on the Yield and Water Use of Crops.  No. 027, Response of
     Vegetation to Carbon Dioxide, U.S. Department of Energy, Carbon
     Dioxide Research Division, and the U.S. Department of Agriculture,
     Agricultural Research Service, Washington, D.C.  75 pp.

Kimball, B. A., J. R. Mauney, J. W. Radin, F. S. Nakayama, S. B. Idso,
     D. L. Hendrix, D. H. Akey, S. G. Allen, M. G. Anderson, and W. Hartung.
     1986.  Effects of Increasing Atmospheric CO2 on the Growth, Water
     Relations, and Physiology of Plants Grown under Optimal and Limiting
     Levels of Water and Nitrogen.  No. 039, Response of Vegetation to
     Carbon Dioxide, U.S. Department of Energy, Carbon Dioxide Research
     Division, and the U.S. Department of Agriculture, Agricultural
     Research Service, Washington, D.C.  125 pp.

Kimball, B. A., J. R. Mauney, D. H. Akey, D. L. Hendrix, S. G. Allen,
     S. B. Idso, J. W. Radin, and E. A. Lakatos.  1987.  Effects of
     Increasing Atmospheric CO2 on the Growth, Water Relations, and
     Physiology of Plants Grown under Optimal and Limiting Levels of
     Water and Nitrogen.  No. 049, Response of Vegetation to Carbon
     Dioxide, U.S. Department of Energy, Carbon Dioxide Research
     Division, and the U.S. Department of Agriculture, Agricultural
     Research Service, Washington, D.C.  124 pp.