Environmental improvement operations with Furusato no Mori (local ...

Environmental improvement operations with Furusato no Mori (local forests)
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Fig.4 Noise measurement results
4-2-4 Estimates of the soundproofing effect of the Espec forest
At the slope in front of KTC facing the Chugoku highway, the tree height is currently 1 to 2
meters, and there is almost no soundproofing effect. The noise at point A3 in Fig.5 is
approximately 75 dB. If the two rows of forested zones grow well, in 10 years the tree height
is expected to reach 6 to 7 meters. 1) The types of trees composing the forest and the forest
density differ slightly, but if we assume that this will achieve a similar soundproofing effect
to that of the Kashihara Bypass highway vegetation, we can estimate that a single zone of
trees will create a damping of -7 dB, and two zones will achieve a damping of -14 dB.
Fig.6 presents examples of the effects of noise levels on people. In the future, the
soundproofing effect of the forest is predicted to suppress the effect of vehicular traffic noise
and create a pleasant work environment surrounded by the forest.
Fig.5 Soundproofing effect of the Espec forest
ESPEC Technology Report No.17