THE EFFECT OF RAINFALL VARIATION ON PALM OIL PRODUCTIVITY IN NORTH SUMATRA

• Main Author: Sirait, Rinaldi
• Format: Final Project
• Language: Indonesia
• Subjects: Geologi, hidrologi & meteorologi
• Online Access: https://digilib.itb.ac.id/gdl/view/70579
• Institution: Institut Teknologi Bandung

Indonesian region is crossed by the equator and is located between the two continents (Australia and Asia) and the two oceans (Pasific and Indian). This position causes the region to have varied rainfall. The variation in rainfall indirectly affect foodstuffs, welfare of life and the social economy of the community. This study examines the effect of variations in rainfall on oil palm productivity in North Sumatra with monthly rainfall data from 2002-2018, oil palm productivity from 2012-2017, Nino 3.4 index, and dipole mode index (DMI). The butterworth bandpass filter method is used to filter rainfall with the highest power spectrum. Rainfall data is used to see the response to the large-scale climate phenomena, also to see the effect on oil palm productivity. The rainfall pattern at the observation station is equatorial. Based on the power spectrum analysis, there are three highest periods, namely semiannual, annual, and interannual. The effect of ENSO and IOD phenomena on rainfall is different at each station, the strongest ENSO phenomenon is at KGPAR stations with a correlation -0.46, while the strongest IOD phenomena is at KAMBT stations with a correlation -0.365. Station whose correlation is in accordance with ENSO and IOD phenomena are only at KBDSL station with a correlation -0.32 to ENSO and -0.17 to IOD. Generally, the effect of these phenomena is weak. The semiannual rainfall pattern has a strong correlation to oil palm productivity at several stations, while the annual rainfall pattern has a strong effect on oil palm productivity at all stations. The interannual pattern of rainfall has a strong correlation at different stations, in general the strong correlation is at lag 0, 6 and 12.