SPATIO-TEMPORAL ANALYSIS OF RICE FIELD PHENOLOGY USING SENTINEL-1 IMAGE IN KARAWANG REGENCY WEST JAVA, INDONESIA
Keywords:Rice field, Phenology, Sentinel-1, Spatiotemporal analysis
The paddy is an important food crop for Indonesian people. It has become the primary staple food and the most gradually increased crop regarding its productivity. It recorded in 2015 that national production for paddy field was 15.13% produced by West Java province. With the national food security issues, monitoring in rice field growth becomes important to give some baseline information regarding the provision of staple food. The phase begins when the rice is planted in the ground and ends when the rice is ready for harvesting. Rice phenology divided into five classes, namely, land preparation, early vegetative, late vegetative, generative, and harvesting. One of the effective ways in monitoring is through rapid measurement using a remote sensing system, in this case, Sentinel-1 Synthetic Aperture Radar (SAR). The objective of the study to implement Sentinel-1 image in a spatiotemporal analysis of the rice field phenology. Sentinel-1 images at the C-Band are capable of monitoring rice phenology. The study aims to provide a spatial and temporal assessment of rice phenology in Karawang using Sentinel-1 images. As results, in northern irrigation area, the paddy is grown quickly even it receives water last compared to southern and middle Karawang irrigation areas.
Furthermore, we found that the rice phenology phase distribution in Karawang does not follow the irrigation pattern. Rice in northern irrigation areas have the lowest backscatter values. The temporal analysis shows that rice reaches the harvesting stage quicker in dry season compared to the rainy season with the same backscatter values.