Table 1. Select physio-chemical properties of the willow biochars used in this study (after Gregory et al [36]).
| Parameter | 350°C Biochar | 550°C Biochar |
|---|---|---|
| pH | 8.6 | 8.6 |
| C content (g kg -1 ) | 739 | 774 |
| N content (g kg -1 ) | 8.0 | 7.0 |
| H content (g kg -1 ) | 35 | 33 |
| Ash content (%) | 5.6 | 4.1 |
| Surface area (m 2 g -1 ) | 6.2 | 59.8 |
| 1 M HCl-extractable K (g kg -1 ) | 11.9 | 10.7 |
| 1 M HCl-extractable Ca (g kg -1 ) | 23.6 | 24.0 |
| 1 M HCl-extractable Mg (g kg -1 ) | 1.5 | 1.4 |
| 1 M HCl-extractable SO 4 -S (g kg -1 ) | 1.9 | 1.8 |
| 2% formic acid-extractable P (g kg -1 ) | 0.7 | 0.8 |