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Fig. 3. Soil organic carbon (OC) and total soil N concentrations in the top 10 cm before (15 April) and/or after (5, 13, 19, and 31 May) litter application, incorporation, and rice planting, but before flooding, by location for five litter rates and an unamended control. Significant differences in total soil N among litter rates, denoted with an asterisk (*), occurred on 5 and 13 May. LSD0.05 values are 0.006 and 0.008 for 5 May and 0.012 and 0.015 for 13 May, for comparing total soil N among litter treatments and for comparing a litter treatment to the unamended control, respectively. Significant differences in soil OC among litter rates, denoted with an asterisk (*), occurred on 5, 13, and 19 May. LSD0.05 values are 0.05 and 0.06 for 5 May and 0.06 and 0.07 for 13 and 19 May for comparing soil OC among litter treatments and for comparing a litter treatment with the unamended control, respectively. Soil OC in the 134 kg total N ha–1 litter rate at PTBS (P = 0.012) and total soil N (P = 0.032) in the 67 kg total N ha–1 litter rate, total soil N in the 202 kg total N ha–1 litter rate (P = 0.038), and soil OC in the unamended control (P = 0.032) at RREC decreased significantly over time.
