Dynamic monitoring of drought conditons in Henan province based on LAI-TS space

Drought occurs frequently in the world and it has great influence on the crops. Satellite remote sensing has been widely used in drought monitoring because of its wide range, fast information and short cycle. Temperature vegetation dryness index based on NDVI-Ts space is widely used to assess drought conditions. In this study, LAI-Ts space, constructed from MODIS MOD15A2 and MOD11A2 products, was used to replace the NDVI-Ts feature space and drought condition of winter wheat in Henan province was evaluated from February 26 to June 1 during 2000–2015. The results show that there is a negative correlation between TVDI and soil moisture and LAI-Ts space can be used to monitor drought status. The LAI-Ts feature space is a triangle in the low vegetation cover and evolves into a trapezoid with the improvement of vegetation cover. Drought is mainly distributed in the Midwest, southwest and northern regions in Henan province.