Using crop simulation model to study the time lag between precipitation and NDVI and its effect on NDVI based agricultural applications

One of the problems in normalized difference vegetation index (NDVI) based agricultural applications is the time lag between precipitation and NDVI. In this study, the CERES-Wheat model under decision support system for agrotechnology transfer shell was used to simulate the time lag between precipitation and NDVI under minted conditions in the Guanzhong Plain, China. The results showed that there were about 14 to 37 days´ time lags between precipitation and NDVI, and the time lags depended on the growing stages of winter wheat. The time lag was about 14 days at the crop´s tasselling stage, while it was about 37 days for the crop´s reviving stage. The results also indicated that there were year to year variations of the time lags and the time lag should be considered for NDVI based agricultural applications