Abstract:
Using MODND1D China′ s 500 m resolution NDVI product data,changes of NDVI in each growth period of winter wheat in Hebei Province from October 2018 to May 2019 were analyzed,and a large-area dry hot wind process in Hebei Province during winter wheat filling period on May 22,2019 was analyzed to compare changes of NDVI before and after dry hot wind.Results showed that NDVI could better reflect growth of winter wheat in each growth period and effect of dry hot wind on winter wheat filling period.When dry hot wind occurred,NDVI showed an obvious downward trend,and its downward range increased with aggravation of dry hot wind disaster.