Potassium dynamics of a forest soil developed on a weathered schist regolith
Soils of the humid tropics are poor in available potassium due to intensive weathering and leaching of nutrients. A study was conducted to investigate the mineralogy and potassium supplying capacity of a forest soil developed on a weathered schist regolith. The quantity–intensity (Q/I) approach was...
| Main Authors: | , |
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| Format: | Article |
| Language: | English |
| Published: |
Taylor & Francis
2013
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| Online Access: | http://psasir.upm.edu.my/id/eprint/30697/ http://psasir.upm.edu.my/id/eprint/30697/1/Potassium%20dynamics%20of%20a%20forest%20soil%20developed%20on%20a%20weathered%20schist%20regolith.pdf |
| Summary: | Soils of the humid tropics are poor in available potassium due to intensive weathering and leaching of nutrients. A study was conducted to investigate the mineralogy and potassium supplying capacity of a forest soil developed on a weathered schist regolith. The quantity–intensity (Q/I) approach was used in thisstudy. The schist regolith showed deep weathering and intense leaching throughout the profile, resulting in low cation exchange capacity (CEC) and available K in soil and saprolite layers. The mineralogy of the regolith was dominanted by kaolinite, gibbsite and goethite. Feldspar, mica and mica–smectite minerals were observed in the lower saprolite layers. The Q/I parameters showed that the soils and saprolites were low in K supply power. This observation was attributed to weathering and intense leaching. The free energy values of K replacement (ΔG r°) also suggest that soils and saprolites of the schist regolith were deficient in K. The Q/I parameters significantly correlated with organic carbon and clay content, CEC, pH and exchangeable K. |
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