APPENDIX 

 SOILS OF SOUTHEASTERN FLOODPLAINS 



Tables A-1 through A-8 describe soil 

 characteristics in sampled dominance types 

 and river floodplain classes within the 

 study area. 



Soil samples were collected non- 

 randomly from a depth of 8 to 30 cm (3 to 

 12 inches) below surface litter zones, in 

 the center of the most mature group of 

 trees. No samples were taken from atypi- 

 cal microtopographic relief features at 

 the site, nor were samples taken where 

 there was evidence of logging, vehicle 

 passage, scour channels, or upland erosion 

 sources. 



Mechanical analysis of percent clay, 

 silt, and sand was by the Bouyoucos 

 method. Samples with very high organic 

 matter were subjected to hydrogen peroxide 



or ashed at 500°C for 4 hours prior to 

 analysis. 



Organic matter was determined by the 

 Walkley-Black method. Depending on the 

 amounts of silt and clay present, organic 

 matter may be overestimated. The error of 

 overestimation due to water driven off 

 from clay and silt was computed on the 

 basis of 8% error with 5% clay-silt and 

 30% error with 85% clay-silt (Broadbent 

 1953; Klawitter 1962); corrected percent 

 organic matter appears in parentheses in 

 Tables A-1 through A-8. 



Macronutrient concentrations were 

 determined by plasma emission spec- 

 trometry, following extraction by the 

 double-acid method. 



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