Analysis of Spatial Patterns of Multiple Cropping Systems in Thailand Using Multi-temporal NDVI Data

The objective of this research is to investigate the spatial patterns of multiple cropping systems in Thailand by using temporal NDVI. The data used in this study are 16-day composite NDVI over the period of 2001-2005. After the data preprocessing the fast Fourier transform was applied to the NDVI data on a per pixel basis for the entire study area. The mean NDVI and the amplitudes of the first three harmonics and phase in the first harmonic were used to identify the cropping information. The result showed that area with one cropping system mostly existed on middle or high terrace in ChaoPraya basin and Khorat plateau while two seasons or three seasons per year cropping systems were mostly distributed in flood plain of ChaoPraya River and Mun River. Because perennial tree crops are their major crop types in the southern peninsula and south-east coastal region of Thailand and FFT used in the paper is based on one year cycle, the extraction error is greater in these regions than other regions. The result was assessed by statistic data and CBERS data. It was shown that cropping information in most parts of Thailand coincided well with other data except southern peninsula and south-east coastal region.