## 4 Discussion
In the III distance category, higher sound levels compared to the present study were found in areas P1 and P3 (5-10 dB), while lower levels were noted in areas P2 and P4 (1.5-5.5 dB). Studies on species richness and the number of individuals at varying distances from the road revealed the impact of traffic noise on both the number of individuals and the number of species. The lowest number of birds was recorded at the measuring points along the traffic routes. Generally, the number of individuals and species increased in the II and III distance categories. The most substantial negative impact of traffic routes on birds was found in a distance of up to 250 m [81]. This spatial range of the impact of road noise on forest birds is supported by research presented in the paper [85], which states that the acoustic impact distance of the transport route was approximately 300 m. The most noise-sensitive species were those that communicate using low-frequency sounds and nest near the ground. According to [86], traffic noise pollution is the most critical factor influencing bird density in a forest environment at distances greater than 50 m from the road. Similar findings are presented in the paper [40], which concluded that noise pollution in protected areas significantly affects both bird species richness and individual abundance near transport infrastructure, with highways exerting a more pronounced negative impact than railways. In other studies [87], the detrimental effect of traffic volume on species diversity and bird abundance along roads was observed. Available research indicates a negative impact of traffic noise on birds at levels above 47 dB [23], while a slightly higher harmful threshold of 53 dB is noted in the paper [88]. Furthermore, the adverse effects of noise on birds persist for more than 3 h after the noise event. This implies that the acoustic impact on birds is not merely temporary but may have lasting effects on their behavior [89]. Thus, the level of traffic noise in Roztoczanski National Park, directly along the traffic routes, as determined by conducted studies and the cited pilot studies, negatively impacts birds. Noise monitoring in remote or extensive protected areas is costly and often technologically limited. The absence of standardized noise limits in protected areas complicates the implementation of clear and feasible guidelines for industries operating near these zones [90]. Special attention should be given to various sources of noise, such as road traffic \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \multirow{2}{*}{**Research Area**} & \multicolumn{4}{c}{**Sound Level at Different Distances from the Traffic Route [dB]**} \\ \cline{2-7}  & **I Distance Category** & **II Distance Category** & **III Distance Category** & **III Distance Category** \\ \hline P1 & 64.2 * & 67.3 ** & 54.5 * & 43.4 ** & 51.8 * & 41.5 ** \\ P2 & 47.5 * & 63.3 ** & 37.8 * & 45.3 ** & 35.1 * & 40.6 ** \\ P3 & 56.9 * & 68.4 ** & 47.2 * & 42.3 ** & 44.5 * & 39.6 ** \\ P4 & 53.6 * & 66.8 ** & 43.9 * & 38.3 ** & 41.2 * & 42.7 ** \\ \hline \hline \end{tabular}
* Results are presented in [81]. ** Own results.  
\end{table} 
Table 7: Results of equivalent sound level measurements in Roztocze National Park. and tourism activities [11]. Quantifying noise mitigation as an ecosystem service is crucial for understanding how the distribution, development, or fragmentation of protected areas affects their ability to provide silence and reduce noise [91]. Noise impact assessments on biodiversity should include acoustic monitoring and soundscape analysis, which will provide insights into the level of anthropogenic noise in natural areas and its effect on the soundscape's composition [92]. Additionally, it is important to consider that methods based on decibel indicators (such as \(L_{Aeq}\) or \(L_{den}\)) do not fully capture the response to environmental noise, hindering the development of an effective management strategy.