Publications

Tatsumi, K (2016). Cropping intensity and seasonality parameters across Asia extracted by multi-temporal SPOT vegetation data. JOURNAL OF AGRICULTURAL METEOROLOGY, 72(4-Mar), 142-150.

Abstract
Detailed analyses are presented of cropping intensity (CI) and crop-seasonality parameters, such as the start and end of a season, the length of a season, and the seasonal amplitude for the period 1999-2010 across Mainland Asia. The analyses used fitted Normalized Difference Vegetation Index (NDVI) time-series data derived from SPOT VEGETATION 10day synthesis (VGT S10) instruments. Savitzky-Golay noise filtering was applied to the NDVI time series, and the results of an automated extraction procedure were compared with the results of other research analyses. The results indicated that: 1) the projected spatial distribution of CI agreed with other analyses; 2) detected double-cropping regions generally extend over large areas equipped for irrigation; 3) the developed extracting algorithm was capable of estimating CI within Mainland Asia; 4) measured spatial variation at the start of a season adequately represented the crop calendar for each grid and region; 5) low standard deviations (SD) for the start of seasons and seasonal amplitude of NDVI across the period 1999-2010 were closely related to the presence of irrigated cropland, and SD values were relatively high for arid, rainfed zones; 6) there were large elements of uncertainty in estimations of cropping-seasonality parameters caused by (i) cloud contamination of images, (ii) the single setting of the smoothing filter and determinations of seasons' starts/ends, and (iii) spatial and temporal resolution of satellite data. Detailed analyses of crop seasonality will contribute to progress across a range of agricultural concerns, including local and large-scale food security and the management of complex agricultural systems.

DOI:
10.2480/agrmet.D-16-00003

ISSN:
0021-8588