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ŠUMARSKI LIST 7-8/2022 str. 62     <-- 62 -->        PDF

difference between the average noise levels according to the diameter classes was examined at the 0.05 significance level with the One-Way ANOVA method.
SPreAD-GIS noise propagation model – SPreAD-GIS model širenja buke
The noise propagation map of the study area was developed with the SpreAD-GIS by using the noise values ​​collected from the chainsaw. SPreAD-GIS, an open source software, has been adapted to the ArcGIS 10.4 software environment using ModelBuilder and Python algorithms. SPreAD-GIS takes into account six propagation factors (spherical propagation, atmospheric absorption, land cover and vegetation, wind, terrain structure, predicted noise propagation) to calculate the spatial propagation of noise (Reed et al. 2009). Among the noise propagation factors, the spherical propagation loss is calculated depending on the distance from the noise source. Atmospheric absorption loss is calculated as a function of air temperature, relative humidity and altitude. Losses due to land cover and vegetation are calculated according to the values ​​absorbed by the ground and scattered by the vegetation according to the land cover types (i.e. coniferous forest, hardwood forest, agriculture/grassland/herbaceous, shrubland, bare land, water/swamp, urban). Wind-induced loss is calculated according to the prevailing wind direction, wind speed and seasonal conditions.
The losses due to the terrain structure are calculated according to the decrease in the sound level due to the barrier effect of the hills or ridges on the site. Finally, predicted noise propagation is calculated depending on the difference between the noise emitted from the measured source and the ambient noise level. Thus, it can be determined that the noise emitted from the source can be heard by exceeding the ambient noise and adversely affects the wildlife in the area (Reed et al. 2009). SPreAD-GIS enables the modeling of noise propagation for 1/3 octave frequency bands (400, 500, 630, 800, 1000, 1250, 1600, 2000 Hz) by considering different noise sources. In this way, noise levels from different machines operating simultaneously can be determined and maps representing noise propagation can be produced.