Hanson, P. J., D. E. Todd, J. S. Riggs, M. E. Wolfe, and E. G. O'Neill. 2001. Walker Branch Throughfall Displacement Experiment Data Report: Site Characterization, System Performance, Weather, Species Composition, and Growth. ORNL/CDIAC-134, NDP-078A. Carbon Dioxide Information Analysis Center, U.S. Department of Energy, Oak Ridge National Laboratory, Oak Ridge, Tennessee, U.S.A.


APPENDIX B:

PHYSICAL AND CHEMICAL CHARACTERISTICS OF THE SOILS OF THE WALKER BRANCH THROUGHFALL DISPLACEMENT EXPERIMENT SITE

Initial characteristics of the TDE typic Paleudult soils (Fullerton cherty silt loam). Most data are from Tables 55-58 of Peters et al. (1970), supplemented by measurements on the TDE site.

Physical characteristics (sil = silt, sic = silty clay, c = clay) 
                                                             Peters    Peters    Joslin/Wolfe
                                                             Coarse    Coarse       Coarse
Horizon Depth   Bulk density   Texture Sand    Silt    Clay Fraction  Fraction     Fraction 
        (cm)      (g cm^-3)             (%)     (%)     (%)  % (g/g)   %(v/v)       %(v/v)

A       0-7         1.06       sil      34      63       3        30      12.0        14.2
E       7-33        1.27       sil      28      60      12        29      13.9        14.2
AB      33-43       1.43       sil      28      64       8        36      19.4        17
B1      43-51       1.31       sil      24      56      20        31      15.3        17
B21t    51-71       1.29       sic      17      43      40        18       8.8        17
B22t    71-107+      1.2       c        13      36      51        17       7.7        --
Exchangeable cations (CEC = cation exchange capacity) 
Horizon  pH   CEC        Ca        Mg         K          Base
                                                      saturation
            (meq/100g) (meq/100g) (meq/100g) (meq/100g)  (%)

A        4.5  5.64       0.68      0.17       0.11       29
E        4.2  1.94       0.09      0.04       0.03        9
AB       4.4  2.08       0.12      0.04       0.04       14
B1       4.2  2.73       0.08      0.04       0.03        7
B21t     4.2  5.42       0.1       0.11       0.03        6
B22t     4.2  8.92       0.15      0.2        0.05        6
Elemental analysis (O.M. = organic matter) 
Horizon     Ca      Mg      K       Fe     N        P         O.M.
            (%)     (%)     (%)     (%)    (%)      (%)       (%)

A           0.06    0.08    0.37    0.96   0.158    0.02      6.54
E           0.05    0.1     0.45    1.47   0.05     0.02      1.75
AB          0.03    0.1     0.4     1.43   0.031    0.01      0.65
B1          0.06    0.12    0.56    1.68   0.031    0.02      0.62
B21t        0.04    0.22    0.57    2.19   0.041    0.01      0.63
B22t        0.05    0.23    0.72    2.48   0.039    0.02      0.62
Root distribution by depth (J. D. Joslin, Tennessee Valley Authority, personal communication) 
Depth   % of all roots
(cm)
0-30          66
30-60         23
60-90         11
REFERENCE

Peters, L. N., D. F. Grigal, J. W. Curlin, and W. J. Selvidge. 1970. Walker Branch Watershed Project: Chemical, physical and morphological properties of the soils of Walker Branch Watershed. ORNL/TM-2968. Oak Ridge National Laboratory, Oak Ridge, Tennessee.