Figure 4 depicts the relationship between yield and relative yield with either exchangeable Ca or Mg iiI the acid sulfate soil. The correlation between yield and exchangeable Ca was poor, with low R2 value (Figure 4A). The Pearson Correlation Coefficient was 0.32 with probability of 0.058. Thus, the relationship between the two parameters was significant at 5 % level. The same is true for the correlation between relative yield and exchangeable Ca (Figure 4B). As the relationship is poor, it is unable to detennine the critical exchangeable Ca for rice cultivation on this particular acid sulfate soil. Nonetheless, there is indication that rice yield improves on GML application