Coapplication of Chicken Litter Biochar and Urea Only to Improve Nutrients Use Efficiency and Yield of Oryza sativa L. Cultivation on a Tropical Acid Soil

Table 5

Effects of biochar and nitrogen fertilization on soil chemical properties in the pot study.

Treatment	T1	T2	T3	T4	T5	T6	T7	T8
pHw	5.3^b  ±  0.10	5.2^b  ±  0.07	5.6^a  ±  0.06	5.8^a  ±  0.07	5.8^a  ±  0.06	5.9^a  ±  0.08	5.8^a  ±  0.01	5.7^a  ±  0.09
	%
Organic matter	9.80^c  ±  0.48	17.0^b  ±  1.47	20.5^ab  ±  1.04	20.0^ab  ±  1.00	19.5^ab  ±  0.29	22.0^a  ±  1.08	18.8^ab  ±  1.03	19.3^ab  ±  1.03
Total carbon	1.13^c  ±  0.06	1.97^b  ±  0.17	2.38^ab  ±  0.12	2.32^ab  ±  0.12	2.26^ab  ±  0.03	2.55^a  ±  0.13	2.18^ab  ±  0.12	2.23^ab  ±  0.12
Total N	0.077^a  ±  0.007	0.056^a  ±  0.004	0.063^a  ±  0.007	0.084^a  ±  0.006	0.070^a  ±  0.008	0.070^a  ±  0.008	0.084^a  ±  0.016	0.077^a  ±  0.007
	mg kg^−1
Available NO^3−	1.05^c  ±  0.20	1.93^abc  ±  0.34	2.10^abc  ±  0.29	2.45^a  ±  0.45	2.10^abc  ±  0.29	2.28^ab  ±  0.18	1.75^abc  ±  0.20	1.23^bc  ±  0.18
Exchangeable	1.75^c  ±  0.20	8.76^a  ±  0.45	9.81^a  ±  0.70	10.33^a  ±  0.44	10.05^a  ±  0.44	10.51^a  ±  0.40	10.16^a  ±  0.35	4.55^b  ±  0.45
Exchangeable P	3.75^c  ±  0.24	7.21^c  ±  0.77	19.6^ab  ±  0.92	18.56^ab  ±  0.96	17.07^b  ±  4.01	18.23^ab  ±  0.77	17.59^ab  ±  0.53	21.26^a  ±  1.40
Total P	70.08^d  ±  0.65	116.65^c  ±  8.78	225.45^a  ±  16.34	187^b  ±  5.73	187.65^b  ±  4.19	202.44^ab  ±  5.75	214.34^b  ±  29.05	183.15^b  ±  19.42
	cmol kg^−1
CEC	6.60^ab  ±  0.15	6.35^b  ±  0.07	7.90^a  ±  0.30	7.45^ab  ±  0.44	6.95^ab  ±  0.26	6.18^b  ±  0.11	7.33^ab  ±  0.30	7.13^ab  ±  44
Exchangeable Acidity	0.68^a  ±  0.027	0.68^a  ±  0.006	0.37^b  ±  0.014	0.35^bc  ±  0.016	0.34^bc  ±  0.005	0.32^bc  ±  0.008	0.31^bc  ±  0.020	0.29^c  ±  0.011
Exchangeable Al^3+	0.53^a  ±  0.013	0.53^a  ±  0.009	0.22^b  ±  0.009	0.22^b  ±  0.006	0.24^b  ±  0.015	0.24^b  ±  0.009	0.22^b  ±  0.010	0.20^b  ±  0.008
Exchangeable H^+	0.15^ab  ±  0.023	0.18^a  ±  0.013	0.15^ab  ±  0.014	0.13^ab  ±  0.020	0.09^b  ±  0.012	0.09^b  ±  0.014	0.09^b  ±  0.012	0.09^b  ±  0.015
Total K^+	2.06^a  ±  0.32	1.45^a  ±  0.14	1.57^a  ±  0.26	1.38^a  ±  0.12	1.58^a  ±  0.14	1.61^a  ±  0.33	1.28^a  ±  0.25	1.34^a  ±  0.12
Exchangeable K^+	0.30^ab  ±  0.03	0.18^b  ±  0.05	0.31^ab  ±  0.02	0.28^ab  ±  0.05	0.31^ab  ±  0.02	0.37^a  ±  0.05	0.21^b  ±  0.03	0.27^ab  ±  0.03
Exchangeable Cu^2+	0.050f  ±  0.0016	0.060^e  ±  0.0028	0.082^c  ±  0.0018	0.089^c  ±  0.007	0.097^b  ±  0.0023	0.103^ab  ±  0.0012	0.110^a  ±  0.0013	0.072^a  ±  0.0026
Exchangeable Mn^2+	0.15^ab  ±  0.014	0.13^ab  ±  0.004	0.17^ab  ±  0.002	0.13^ab  ±  0.027	0.13^ab  ±  0.036	0.08^ab  ±  0.031	0.15^ab  ±  0.019	0.18^a  ±  0.003
Exchangeable Fe^2+	0.38^ab  ±  0.10	0.53^a  ±  0.04	0.37^ab  ±  0.03	0.30^ab  ±  0.08	0.30^b  ±  0.08	0.18^b  ±  0.03	0.26^b  ±  0.04	0.35^b  ±  0.01
Exchangeable Zn^2+	0.006^ab  ±  0.0003	0.005^ab  ±  0.0003	0.008^ab  ±  0.0009	0.007^ab  ±  0.0006	0.006^ab  ±  0.0010	0.007^ab  ±  0.0010	0.009^a  ±  0.0017	0.004^b  ±  0.0006
Exchangeable Na^+	6.28^a  ±  2.07	3.42^a  ±  0.90	6.46^a  ±  0.97	5.64^a  ±  3.35	2.60^a  ±  0.10	6.91^a  ±  2.10	6.88^a  ±  1.98	4.64^a  ±  1.98
Exchangeable Ca^2+	17.59^b  ±  2.27	20.35^b  ±  1.49	32.74^a  ±  1.38	29.16^ab  ±  1.43	26.69^ab  ±  3.13	25.16^ab  ±  4.02	28.89^ab  ±  2.91	27.03^ab  ±  1.25
Exchangeable Mg^2+	6.67^a  ±  0.86	4.08^b  ±  0.24	6.75^a  ±  0.44	5.45^ab  ±  0.21	4.05^b  ±  0.52	3.97^b  ±  0.28	3.29^b  ±  0.51	7.57^a  ±  0.59

Different letters within a row indicate significant difference between means of four replicates ± standard error using Tukey’s test at ≤ 0.05.