prilagođeno pretraživanje po punom tekstu

ŠUMARSKI LIST 7-8/2022 str. 60     <-- 60 -->        PDF

environment where the sound is emitted, meteorological parameters (temperature, wind, air movements), the absorption of the ground, the presence of forests and wooded areas, and natural and/or artificial barriers in the environment (Aydın 2015).
Some special units and indicators are used in the measurement and evaluation of sound. The A-weighted sound pressure level (dB or dBA) is the unit of sound pressure in which the middle and high frequencies to which the human ear is sensitive are emphasized. The most commonly used sound levels are A-weighted sound levels in noise control studies. Noise, which affects human health physiologically, physically and psychologically, is an environmental pollution that reduces people’s performance in working environment, education and home life. Scientific studies conducted on the subject show that more than 20% of the world population is exposed to noise levels above normal and approximately 60% of the European population is exposed to high noise levels during the day (Rivas et al. 2003).
Within the framework of the sustainability of forest resources, the process of benefiting from the functions offered by forests continues and it is expected that this situation will continue in the face of increasing population. When considering the business objectives of the forest resources, one of the most important purposes is the production of wood raw material. Harvesting operations in forestry is one of the working environments where the noise effect can be intense. Depending on the difficulty of the work and the type of equipment used, the effects of the noise exposure of forest workers and operators vary (Neitzel and Yost 2001, Serin and Akay, 2010). The most commonly used equipment in harvesting operations is the chainsaw, which is used in tree cutting, delimbing and bucking stages in the production of forest products. Studies on this subject have shown that the chainsaw is one of the most critical equipment in terms of noise level as well (Cavalli et al. 2004, Potocnik and Poje 2010).
Potocnik and Poje (2010) investigated the chainsaw noise level during forest harvesting operation and found that in addition to moving away from the noise source, atmospheric absorption and other factors were also effective in the reduction of noise propagation in the forest. They reported that they reached the natural noise level of the forest at 252 m away from the noise source generated by the chainsaw. Melemez et al. (2012), as a result of the health examinations of forest workers in harvesting operations, found that the inner ear nerves of the forest worker were damaged due to the noise of the chainsaw. It was stated that the workers could hear the deep sounds they encountered in daily life, but they had difficulties hearing the high-pitched sounds such as telephone and doorbell rings. Taş et al. (2018) measured the average noise level as 80.18 dBA in a study where the effect of the chainsaw on the operator was investigated. The maximum noise level was measured at the back-cut stage (100.77 dBA) of tree felling operation. Neri et al. (2018) investigated the effect of using electric chainsaw in terms of vibration and noise effects during forest harvesting operation in coniferous forests. After analyzing the noise measurements, they found that the noise level generated by Li-Ion battery saws was between 81 and 90 dBA.
Noise is a pollution element that has an impact on human health, therefore it must be controlled like all other environmental pollution elements. Noise maps showing noise propagation can be effectively used in the assessment and control of the noise impact. The noise map is defined as a numerical model of noise sources (Probst and Huber 2003). They are used to calculate average noise levels in an area, to determine whether the noise is within acceptable limits, and to identify risky areas where employees are adversely affected (Aydın 2015). Barber et al. (2011) investigated the effect of anthropogenic noise caused by energy systems, aircraft and roads in US national parks (Mesa Verde, Grand Teton and Glacier). They developed a noise propagation model with one of the well know GIS based software, called SPread-GIS, by measuring the noise emitted from oil and gas compressor systems located near Mesa Verde National Park. In the model, they found that the noise emitted from 64 compressors was 34.8 dBA in average throughout the park, and 56.8 dBA in the densest area adjacent to the park. The studies conducted on the mapping of anthropogenic noise propagation caused by forestry equipment are rather limited. Proto et al. (2016) examined the modeling of noise propagation caused by harvesting equipment using SPread-GIS software. The measurements were made on the noises caused by the chainsaw during tree cutting, and the tractor and cable logging during the timber extraction from the harvesting unit. They stated that the highest noise emission was realized by the chainsaw.
Knowing that the noise sources and noise levels in a working environment provides important information for determining the effects of noise pollution on different species and ecosystems (Keyel et al. 2017). In a study conducted by Slabbekoorn and Ripmeester (2008), it was stated that the anthropogenic noise that occurs as a result of increasing human activities often interferes with the communication sounds between birds, causing stress in areas such as not being able to receive warning against the predator, not being able to find a partner, and feeding. In a review study conducted by Akay and Acar (2019), how to use SPreAD-GIS program for modeling noise map was described and the main factors affecting noise propagation in forest (i.e. elevation, land use type, temperature, humidity, wind direction and intensity, climate and weather conditions) were evaluated. Kunc and Schmidt (2019) reported that noise is considered as a serious form of environmental change and