Spatio-temporal evolution of forest in Târgu Lăpuș, northern Transylvania, Romania, using Landsat satellite data

Abstract
The use of remote sensing indices in order to obtain information for vegetation distributions, heath and patterns is a popular practice with applicability at different scales of detail. The present article presents an example of using the Normalized Difference Vegetation Index (NDVI) and Change Detection method to identify the spatio temporal evolution of forest area in Târgu Lăpuș city, northern Transylvania, Romania. NDVI method is applied at different NDVI threshold values such as 0.1, 0.15, 0.3, 0.45 and 0.6. For the analyzed area, an area of 1.56 km2 with forest gain and 3.59 km2 with forest loss was identified. The advantage of using this method is the large time gap for which it can be done, in our situation being an analysis for the period 1983-2020 so that we can identify the trend of evolution of areas occupied by forests in a city where spatially built it often extends uncontrollably, affecting the degree of compactness of the forests and implicitly their protection functions.