Yala and Maha Seasons
Sri Lanka experienced severe droughts and floods during the recent years which resulted much crop losses in the paddy production. Effective rainfall periods for the major paddy producing seasons, Maha and Yala seasons are determined according to the crop calendar of the Districts.
Here, the impact of rainfall on the paddy production is analysed for each Districts of Sri Lanka during the period from 1961 to 1980. Significant correlation coefficients reveal the clear effect of rainfall onthe paddy production, especially inharvest acreage in the Wet and Dry zones. The regions in the Wet Zone have significant positive relationship in the Southwest monsoon season and the Dry Zone in the second intermonsoon and Northeast monsoon seasons as their principal cropping seasons.
The Maha rain effects on the sown extent and harvest acreage not only in the same Maha season, but also in the subsequent Yala season sometimes. The excess rainfall amount does not increase the paddy acreage and causes floods even in the drier parts of the country, indicating a negative relationship between rainfall and sown or harvest acreage. Therefore, we can recognize four types of relationships between rainfall and paddy production:(1)significant positive relationship,(2)significant negative relationship, (3) no significant relationship and (4) others, for instance, there is a significant positive relationship below certain critical values and no relationship above the values.