Mapping spatiotemporal dynamics of maize in China from 2005 to 2017 through designing leaf moisture based indicator from Normalized Multi-band Drought Index

•Maize was extracted by combined consideration of vegetation phenology and leaf moisture variation.•Indicator was designed by Ratio of Cumulative Positive slope to Negative slope in NMDI.•The maize mapping method is suitable for national scale application.•Annual maize maps were generated for the first time using MODIS data from 2005 to 2017.•Maize area increased by 33.20% during 2005–2015 but declined by 2.60% during 2015–2017.