Abstract:
Because of the burstiness of the hail and the significant spatial heterogeneity of post-disaster impact, there are relatively fewer studies about hail monitoring and post-disaster evaluation. The typical hail in Gannan county of Heilongjiang province was selected as the study area, remote sensing images of HJ-1A/1B CCD and ground-measured hyperspectral reflectance data were used to carry on hail monitoring and post-disaster evaluation. This paper analyzed the reflection spectral characteristics and vegetation index of crops in different hail disasters extends based on measured spectral data. Hail monitoring and evaluation were conducted by vegetation index classification and ground investigation, using remote sensing image data of two time phases, and then the validation was made with the data of another phase. The results showed that the spectral reflectance characteristics of crops with different disaster degrees were significantly different; It was feasible to carry on hail monitoring by vegetation index classification; The different hail degree range got by NDVI difference value drawings of the RVI appeared coincident with the actual situation; spatial distribution characteristics are analyzed according to remote sensing classification results. The results can provide theoretical and technical support for hail monitoring and evaluation.