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... University, Beijing 100875, China. different methods have been developed to estimate crop yields (Guérif and Duke, 2000; Liang et al., 2004; Walthall et al., 2004; Doraiswamy et al., 2004; Wu, 2004; =-=Xiao et al., 2005-=-; Tao et al., 2005). One practical approach using satellite data is the development of empirical relationships between the integrated Normalized Difference Vegetation Index (NDVI) and crop yield. NDVI...

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...lope and defined the so-called water band index (WI) as the ratio between the reflectance at 970 nm and the one at 900 nm (as a reference wavelength). Gao (1996) defined the normalised difference water index (NDWI), analogously to the wellknown normalised difference vegetation index (NDVI), by using the 1200 nm feature and 860 nm as a reference wavelength. This resulted in a diversity of approaches applied in some more recent studies (Chen et al., 2005; Cheng et al., 2006; Danson and Bowyer, 2004; Fensholt and Sandholt, 2003; Penuelas et al., 1997; Roberts et al., 2006; Sims and Gamon, 2003; Xiao et al., 2005; Zarco-Tejada et al., 2003). Therefore, these indices are also tested in this study and definitions of the indices will be given in Section 2.5. Finally, a continuum removal approach can be applied to the two absorption features at about 970 nm and 1200 nm. This is a way of normalizing the reflectance spectra (Kokaly and Clark, 1999). The maximum band depth, the area under the continuum, and the band depth normalized to the area (Curran et al., 2001) have been used thus far for estimating foliar biochemicals like chlorophyll. Few studies have applied this to the water absorption features at 9...

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...efforts to utilize MODIS time series data sets to identify the inundation periods in rice paddy fields and irrigated agricultural schemes, i.e., flooding and transplanting periods along river systems =-=[30,31]-=-. In these studies, Normalized Difference Vegetation Index (NDVI, MOD13Q1) time-series at 250-meter resolution as well as MODIS Land Surface Water Index (LSWI) time series from 500-meter surface refle...

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...egetation index data from coarse resolution sensors like AVHRR and MODIS [19,21,47-52]. There are various ways to translate multi-temporal information to a map of irrigation. For example, Xiao et al. =-=[48]-=- developed a paddy rice mapping algorithm that uses time series of three vegetation indices, namely the Land Surface Water Index (LSWI), the Enhanced Vegetation Index (EVI) and NDVI, derived from MODI...

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...a ReferencesNormalizedsDifferencesVegetation IndexsNDVIs[39]sRatio VegetationsIndexsRVIs[40]sEnhanced VegetationsIndexsEVIs[41]sSoil-AdjustedsVegetation IndexsSAVIs[42]sLand Surface WatersIndexsLSWI*s=-=[22]-=-sNormalizedsDifference Built-upsIndexsNDBIs[43]sTriangularsVegetation IndexsTVIs[44]sDifferencesVegetation IndexsDVIs[45]sInfrared PercentagesVegetation IndexsIPVIs[46]sPerpendicularsVegetation Indexs...

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... SPOT VGT-derived NDVI images over Mekong delta, Vietnam. Theysemployed unsupervised classification and divergence statistics to determine signaturesseparabilities; and found overall accuracy of 94%.s=-=[4,14]-=-sEmployed MODIS-derived LSWI, NDVI, and EVI images over Southern China, andsSouth and Southeast Asia. They introduced rice mapping algorithm based on thesrelationships between LSWI, NDVI and EVI durin...

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...gy between land surface and the atmosphere [2, 33, 42]. In thissproduct, band 2, centered at 858.5 nm, band 5 at 1240 nm, and band 6 at 1640 nm have beensused for retrieving water content information =-=[12, 19, 39, 47-49]-=-.sRadiative transfer modelsssuch as PROSPECT [50] linked to canopy models show that other biochemical constituentsssuch as dry matter content (cellulose, lignin, nitrogen, etc.) along with canopy stru...