Extracting NDVI temporal profiles of vegetation types in the Rižana spring catchment area from NOAA-AVHRR data using linear mixture model
This paper presents methodology that was used to derive NDVI temporal profiles of the vegetation types in the Rižana spring catchment area. In the methodology the Landsat TM image was used for the classification of the area into vegetation cover classes and to determine proportions of classes within AVHRR pixels. According to the influence of the vegetation types on the water cycling process in the catchment area, six vegetation classes were defined (deciduous forest, grass, agricultural areas, shrub, coniferous forest and areas with no/sparse vegetation). This data and the NDVI data derived from AVHRR satellite images was then used in the linear mixture modelling that was applied to estimate the mean NDVI value of each vegetation class. The resulting temporal NDVI profiles of vegetation cover classes, with exception of class with no/sparse vegetation, are in general in agreement with the observed vegetation characteristics area.