SECTION IV 

 RESULTS AND DISCUSSION 



7. SULFUR DISTRIBUTION IN SELECTED FLORIDA SOILS 



7.1 SPODOSOLS 



Extractable sulfate S was very low throughout the profile in all 

 of the Spodosols studied (Table 12). Extractable S in the surface 

 soils ranged from 1 ppm in a Myakka fine sand from Alachua County to 

 8 ppm in a Leon fine sand from Duval County. Most of these profiles 

 were from rural locations. However, the City of Jacksonville encom- 

 passes Duval County, and the higher S0„ emission rates from industry in 

 that area could account for the higher sulfate-S level. Duval County 

 had one of the highest S0 o emission rates in Florida in 1978. Between 

 100 and 200 kg/ha of S were emitted on a county-wide basis. The aver- 

 age for the entire state is 32 kg/ha. Rainfall in the Jacksonville 

 area was found to contain 43.5 ueq/liter of SOT in 1979 — also among 

 the highest in the State (Brezonik et al. , 1980: Edgerton et al. , 

 I93G) . Spodic horizons contained slightly more sulfate S than the 

 eluviated A2 horizons but less than the surface horizons. 



Extractable sulfate S did not appear to be related to total S in 

 the soil. Extractable S varied little with horizon depth, whereas con- 

 siderable differences were observed in the total S levels. The distri- 

 butions cf the mean total and extractable S level in the nine Spodosol 

 profiles are given in Fig. 7. 



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