Characteristics And Evaluation Of Acoustic Environment Quality In Xinjin County

As one of the main pollution sources,noise pollution has seriously affected people’s daily work and quality of life.Effective control of noise pollution has become an urgent environmental problem in China at present,which is of great significance to improve the urban ecological environment and the quality of life of residents.In this study,the built-up area of Xinjin County,Chengdu City,Sichuan Province is taken as the research object,and the national technical specifications and zoning standards are used to make a comprehensive statistical analysis of the monitoring data of the fixed-point survey of acoustic environment in the county during the 12th Five Year Plan period,to evaluate the acoustic environment quality and the distribution characteristics of noise pollution in Xinjin County during this period,and to use Spearman rank correlationγs to quantitatively analyze the change trend of environmental noise(when the Confidence level is a=5%,n=5,WP=0.90).Combining with EKC Theory and Grey System Theory,this paper studies the relationship between its distribution characteristics,change trend and vehicle flow,GDP,population density.At the same time,the causes and mechanism of noise are discussed.The main conclusions are as follows:(1)The average equivalent sound level of road traffic noise ranges from 64.5d B(A)to 66.6d B(A),and the average value of each year reaches the"good"level,with the highest level in 2011 and 2012;the annual change shows a significant downward trend,and the annual growth trend of the average traffic flow of motor vehicles meets the negative correlation(r~2=0.8577);the pollution distribution has a more obvious space-time characteristics,with light pollution above Mainly concentrated in the early and late peak traffic trunk road convergence,enterprises and institutions concentrated distribution,traffic efficiency is low.It shows that the environmental quality of road traffic in Xinjin County is not simply affected by the single factor of increasing traffic flow,but by the factors of urban development planning and layout,work and rest time,subway construction,road vehicle status,traffic control,environmental protection law enforcement departments’control strength and so on.(2)The average equivalent sound level of environmental noise in urban areas ranges from 51.5d B(A)to 53.0d B(A),which is at a"good"level in each year,with the highest level in 2014;the annual change is generally not significantly increasing,and the annual growth of regional economy(GDP)does not form an inverted U-shaped curve relationship,and the traditional EKC Theory is not fully applicable to the environmental noise emission indicators in Xinjin County The pollution distribution has obvious location and category.The most widely affected area is about 50%of the total domestic noise,followed by industrial noise.It shows that the environment will not improve spontaneously and must be controlled with the help of the government.The environmental quality of Xinjin County’s urban area is relatively complex,which is not only influenced by the GDP growth,but also may be influenced by the scope of people’s living activities,the way of culture and entertainment,business activities,industrial production intensity,urban management and other factors.(3)The average equivalent sound level of noise in the functional area has reached the corresponding standard limit,the highest in 2011,and 53.1d B(A)in the whole county day and night.The annual change of nighttime noise in the four standard areas of the functional area showed a significant upward trend,which was related to the annual change of population density in Xinjin County(r~2=0.2601).It shows that the noise pollution at night on both sides of the main traffic line in Xinjin County is affected to some extent by the population density.(4)The noise of class 1,class 2 and class 3 standard application areas in the functional area does not change significantly in the day and night and in class 4 standard application areas in the daytime;the pollution distribution has obvious seasonality and gradient,and the noise pollution level in the urban area generally conforms to the relevant standards of the acoustic environment function zoning,showing the normal distribution characteristics of the acoustic environment pollution,but there are still local areas,different periods of over standard situation,the spatial and temporal distribution of noise pollution is very unbalanced.It shows that the urban area of Xinjin County has not experienced significant tendentious infrastructure construction or planning adjustment recently,the urban pattern has remained basically stable,the population flow is frequent,the lifestyle is diversified,the production cycle and supervision of industrial enterprises are highly random,and the construction time and location of the urban area are uncertain.According to the above conclusions,during the 12th Five Year Plan period,the overall change of noise pollution level in the built-up area of Xinjin County tends to be stable,and the over standard rate of each monitoring point is low in the daytime and at night.At the end of the paper,it is proposed to strengthen the construction management and guidance of urban traffic,advocate green travel,improve noise protection facilities,strengthen the supervision of construction activities,strengthen guidance and publicity,avoid over concentration of population,pay attention to social management(especially at night),optimize industrial structure,increase the government’s environmental protection investment,reasonable planning and layout,credit management,establish and improve noise Relevant policy system and other prevention and control measures and suggestions.