5.2 Conclusions
MODIS time series dataset was able to monitor impact on drought. Drought-induced reduced in vegetation photosynthesis can be seen in the EVI temporal profiles. Decreasing trend of EVI values over 6-years data were found over major land cover types including rice, crops (sugar cane and cassava), and deciduous forest. Strong pronounced dry-wet “greenness” values due to seasonal vegetation responses were found in this study. The rice, sugar cane, casava and deciduous forest seasonal profiles were driven by water. These agricultural and deciduous forest sites showed the highest wet-dry seasonal contrast with a pronounced dry season from November to April and an increase in wet season from May to October. The evergreen forest seasonal profile showed the least variations and least impact from drought. However, the dominant land cover type, dry paddy rice, exhibited seasonal profiles with large spatial variations due to land use management practices (Figure 5), which resulted in more complex rainfall- vegetation relationship. Therefore, it is suggested that land use practices be taken into account for drought assessment and that the use of other land cover types, i.e. dryland crops be considered.