RICE GROWING PERIOD BASED ON THORTHWAITE MATHERDROUGHT INDEX FOR CLIMATE CHANGE ADAPTATION IN GROBOGAN, CENTRAL JAVA, INDONESIA

Abstract

The length of the dry season due to climate anomalies, which can cause drought. The drought can have an impact on agriculture, including rice production.The purposes of this research are to 1) determine the effect of the drought on rice production in Grobogan district; 2) provide the direction of rice growing period based on Thorthwaite Mather drought index in Grobogan district.

Research steps are as follows: 1) To know the influence of drought towards the rice production, using the comparison between an average of rice production for five years divided by rice field area. 2) Determination of rice growing period using the runoff analysis based on Thorthwaite Mather calculation.

The results of this research showed that: 1) Drought gave negative influence on rice production, it could be seen on the average of rice production. Sub-district which included in a high level of drought showed an average of rice productivity to 5.314 ton/ha, sub-district which included in a medium-level drought had an average of rice productivity to 5.701 ton/ha,  and sub-district which included in a low-level drought had an average of rice productivity 5.902 ton/ha.; 2) Rice growing period obtained from the calculation of runoff is started from December to April.