Click on image to view larger version.
Fig. 4. Soil NO3–N and NH4–N concentrations in the top 10 cm before (15 April) and after (5, 13, 19, and 31 May) litter application, incorporation, and rice planting, but before flooding, by location for fresh and pelletized litter and an unamended control. Significant differences in soil NO3–N among litter rates occurred on 19 and 31 May. LSD0.05 values are 1.50 and 2.60 for 19 May and 2.31 and 4.00 for 31 May for comparing soil NO3–N among litter forms and for comparing a litter form with the unamended control, respectively. Soil NO3–N decreased in the unamended control at PTBS (P = 0.001) and increased in pelletized litter at RREC (P = 0.043) over time.
