Compost and Crude Humic Substances Produced from Selected Wastes and Their Effects on Zea mays L. Nutrient Uptake and Growth
Table 8
Total and exchangeable cations (mg kg−1) in crude humins from different composts.
Cations
Rice straw
Rice husk
Sawdust
EFB
K (%)
2.33b (±0.06)
1.79c (±0.06)
1.95c (±0.02)
2.84a (±0.08)
Ca (%)
1.46a (±0.16)
1.03ab (±0.11)
0.76b (±0.06)
1.44a (±0.09)
Mg (%)
0.79a (±0.08)
0.53bc (±0.05)
0.33c (±0.03)
0.73ab (±0.06)
Na (%)
0.18a (±0.00)
0.14b (±0.01)
0.17a (±0.01)
0.18a (±0.01)
Fe (%)
0.21a (±0.01)
0.07c (±0.00)
0.05c (±0.00)
0.13b (±0.01)
Cu (mg kg−1)
39.70c (±2.23)
29.43d (±2.23)
86.53b (±1.21)
97.50a (±2.82)
Mn (mg kg−1)
226.60a (±16.93)
232.83a (±15.87)
46.57c (±6.42)
148.50b (±6.63)
Zn (mg kg−1)
164.43b (±5.27)
81.33d (±2.65)
117.60c (±1.21)
184.93a (±3.63)
Exchangeable K (cmol kg−1)
38.25a (±1.16)
28.95b (±0.44)
25.79b (±1.83)
37.57a (±1.01)
Exchangeable Ca (cmol kg−1)
12.58b (±0.46)
12.60b (±0.05)
12.45b (±1.13)
21.50a (±0.53)
Exchangeable Mg (cmol kg−1)
6.96b (±0.16)
6.81b (±0.09)
9.50a (±0.58)
10.04a (±0.20)
Exchangeable Na (cmol kg−1)
4.11a (±0.09)
3.10b (±0.04)
3.14b (±0.21)
3.55b (±0.08)
Different alphabets within a row indicate significant difference between means using Tukey’s test at . ( ) values in parenthesis represent standard error of the mean.