Mineralizable N in some Malaysian rice soils
Mineralizable soil N is a very important N source in rice soils. In some cases more than 60% of the N requirement in an N fertilized rice crop is derived from soil N. A laboratory study was conducted to determine mineralizable (N) and mineralization constant (K) of 14 rice soils with varying soil pr...
Saved in:
| Main Authors: | , |
|---|---|
| Format: | Conference or Workshop Item |
| Language: | English |
| Published: |
1988
|
| Online Access: | http://psasir.upm.edu.my/id/eprint/19831/1/ID%2019831.pdf http://psasir.upm.edu.my/id/eprint/19831/ |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| Summary: | Mineralizable soil N is a very important N source in rice soils. In some cases more than 60% of the N requirement in an N fertilized rice crop is derived from soil N. A laboratory study was conducted to determine mineralizable (N) and mineralization constant (K) of 14 rice soils with varying soil properties under submerged condition. Soils were collected at the depth of 0-15cm and incubated for eight weeks. Ammonium N was extracted at 0,2,4,6 and 8 weeks and determined by steam distillation. The ammonium-N mineralized was used to calculate No and K. The No ranged between 20.0 to 154.1mg/kg which represented between 1.0% and 7.3% of the total N. The K values ranged between 0.11 to 0.72Wk-1. The mineralized N at a specified time can be determined by using No and K values. The calculated and the observed mineralized N were compared: the results showed good agreement between the two values. The No and K values were not significantly affected by the total N,organic C and C/N ratio,however there is a significant correlation between No and K (r=0.76). |
|---|