Abstract
The concentration of nitrogen and phosphorous in field water standing on clay loam in eight pots was measured 1, 3, 5 and 7 days after the experiment was conducted. The experimental conditions were as follows: 1. Unpuddled and no fertilizer, 2. Puddled and no fertilizer, 3. Unpuddled and phosphate fertilizer, 4. Puddled and phosphate fertilizer, 5. Unpuddled and synthesized chemical fertilizer, 6. Puddled and, synthesized chemical fertilizer, 7. Unpuddled and coated fertilizer and 8. Puddled and coated fertilizer.
By analysis of variance, the effective factor for nitrogen and phosphorous concentration was the puddling operation. The mean value of T-N concentration in the first day was 9.9mg/L for puddled pots and 2.1mg/L for other unpuddled pots; 2.2mg/L and 0.21mg/L for T-P respectively. The effect of the kind of nitrogen fertilizer seems to be more significant with synthesized chemical fertilizer than others.
