Temporal and spatial evaluation of environmental noise in urban area: a case study in Iran

Environmental noise pollution is a disrupting factor in the urban areas which can lead to adverse health effects, behavior and quality of life. Present study was carried out in Tabriz (Iran) and aimed to achieve a real condition of noise pollution. Thirty-five measurement stations were selected, and noise levels were recorded. The equivalent noise level in (A) frequency weighting network, route-mean-square sound pressure level, minimum sound pressure level, maximum sound pressure level and noise pollution level were computed as applicable indices. Temporal and spatial variability of these noise indices were plotted by Arc GIS. Public awareness about the noise pollution was assessed through interview. Mixed model and pairwise comparisons were used for comparison of noise indices based on stations and times. It was found that noise levels were significantly different and higher than permissible levels at most stations, especially at heavily travelled crossroads and squares. Mean equivalent noise level for morning, noon, afternoon and night was 71.35 ± 7.49, 71.63 ± 4.90, 70.67 ± 4.52 and 68.74 ± 5.22 dB(A), respectively. The noise indices of all stations and measurement times had significant difference (p value = 0.028 and 0.019, respectively). It was observed that in normal traffic, the highest sound levels are produced by buses, trucks and motorbikes due to low-technology engines. Using the horn was the first reflex of the most drivers. A main part of the noise pollution problem of the studied city can be attributed to driving culture and non-compliance with traffic laws.     

Accuracy assessment of noise mapping on the main street

Among the sounds constituting a part of our daily lives, the undesired and disturbing ones are named noise. The noises can be defined as the acoustic energy that affects the physiological and psychological welfare of humans due to its direct or indirect effects on the human health. But, the traffic noise, which is one of the disturbing noises having wide dispersion in urban areas, affects the health of a gradually increasing number of people. The number of studies on measurement, dispersion, and mapping of traffic noise in developed and developing countries is gradually increasing. It can be seen that the studies concentrate on mapping based on the city centers and neighborhoods, where the traffic is intense. In this article, unlike the regional noise measurement studies, the transversal cross sections were established with a certain interval according to the land status along the main street, and the noise measurement points were determined using the global navigation satellite system (GNSS). The daily mean noise levels (L_den) were calculated by performing the measurements at daytime, evening, and nighttime. Using ArcGIS 10.4 software, the accuracy of noise maps created via inverse distance weighting (IDW), radial basis function (RBF), and ordinary kriging (OK) geostatistical analysis interpolation methods and the dispersion effect of traffic noise were compared. According to the visual method and error corrections, it was found that the best noise map was obtained using the RBF method. It is believed that the map provides accurate and reliable results because of the flat land surface, higher noise values measured on the road region, decrease in the noise at the points farther from the road region, and soft transitions between the noise values depending on the distance from the road. In order to take measures in order to decrease or eliminate noise on the main street, the local administrators and decision-makers can make use of these maps, the accuracy of which has been confirmed.     

Evaluation and analysis of traffic noise along bus rapid transit system corridor

Due to increasing motorization, construction of flyovers and growth in transport network, the noise level has exceeded the prescribed limits in many Indian cities. The health implications of high noise levels are being identified as hypertension, sleeplessness, mental stress, etc. Due to this adverse effect of noise level, it is essential to assess the impact of traffic noise on residents and road users. This research is an effort to quantify and analyze the traffic noise emissions along bus rapid transit corridor in Delhi. Field measurements were carried out to understand and assess various aspects of the impact of bus rapid transit system corridor on land use and social lives of residents and road users. The present analysis presents the comparison between observed and predicted noise level at selected corridors and also describes the mitigatory measures to overcome such type of traffic noise pollution through design of noise barrier along the road and motivate people towards the use of public transport system.     

Noise pollution

Noise, sometimes referred to as the unseen pollutant, is the most inescapable form of pollution — and one which poses a long list of potential health hazards. As the world becomes more urbanized, the use of machine-technology increases, and levels of development become higher and more complex, human exposure to noise increases. One authority estimates that the average noise level in the American city is increasing by 1 dB annually.Despite the importance and great scale of the problem, geographers generally have ignored the field of noise pollution research, perhaps because specialized equipment is necessary to accumulate the data required for analysis. As a result, most noise pollution research has been performed by traffic engineers, industrial designers and urban planners to solve immediate problems with little regard for more general consideration. This article provides background which may serve as a foundation for future research on this most significant human problem. The emphasis is upon developments in North America, but reference is made at appropriate points, to noise pollution research in Europe, China and elsewhere. *** DIRECT SUPPORT *** ABI02038 00003     

Unplanned urbanization: Assessment through calculation of environmental degradation index

Urbanization is an inevitable phenomena for the country like Bangladesh. The push and pull factors help to migrate people from rural area to urban area. As a result haphazard and unplanned urbanization create environmental degradation. Survey data reveals that inadequate solid waste disposal services, lack of adequate public water supply, traffic congestion, water logging, air pollution, noise pollution, hill cutting are the main problems in the city area. Concentration of dust as well as SOx, NOx exceeded the allowable limit at the selected points. Groundwater level of Sylhet city has a considerable lowering over the last few decades. It has lowered from 3380 mm below ground in 1982 to 7880 mm below ground. Sylhet is located in highly seismic risk zone but most of the buildings and other structures in this area are constructed without considering earthquake risk. Environmental degradation index was calculated based on economical condition of the country.     

Assessment of heavy metals contamination in deposited street dusts in different urbanized areas in the city of Ma’an, Jordan

190 Street dust samples were collected from nine different localities including high traffic (desert highway), moderate traffic (city center), light traffic (minor streets), residential streets, school gardens, hospital and health centers, industrial sites, parks and background sites (control) of Ma’an area. The concentrations of Fe, Zn, Ni, Pb, Mn, Cu and Cd were analyzed by flame atomic absorption spectrophotometer to assess and to compare road dust contamination levels of metals among the different types of urban environment. The results showed that dust samples from the urban and industrial site contained significant levels of the metals studied compared to the values obtained from the background site. The variation in concentration of the heavy metals determined from different locations was in the decreasing order as: industrial > high traffic > parks > moderate traffic > hospital and health centers > school gardens > light traffic > background sites. The mean concentrations of the metals were in the order of C _Fe > C _Zn > C _Ni > C _Pb > C _Mn > C _Cu > C _Cd where C is the concentration of these metals in solution. Enrichment factor calculations indicated that Cd, Pb, Zn and Ni were highly enriched. Fossil fuel combustion, wear of brake lining materials, traffic emissions and several industrial processes are considered the main sources of these metals. Assessment of the contamination level in dust sample was estimated based on the geoaccumulation index (I _geo), the pollution index, and integrated pollution index (IPI). The values of IPI are in the following order: Pb > Zn > Cu > Ni > Cd > Mn. All the indices for the metals under consideration were either low or corresponded to middle level of contamination. The use of factor analysis showed that anthropogenic activities seem to be the responsible source of contamination for metals in dust samples.     

贵州省城镇用地扩展强度时空分异及影响因素

以贵州省1995年、2000年、2007年TM遥感影像资料为数据源,利用Er-das软件对该三期影像进行矫正和监督分类,应用ArcView进行修改。然后,再以ArcGIS空间分析模块,提取贵州省1995年、2000年、2007年三个时期的城镇土地利用数据。在此基础上,运用城镇扩展强度指数公式计算城镇扩展强度指数,并从交通、经济和自然环境等方面对贵州省城镇土地利用扩展的影响因素进行分析研究。结果表明:(1)2001-2007年,高速扩展城镇16个,高于1995—2000年期间的5个;(2)从空间上看,南北(遵崇公路、贵遵公路、贵新公路及国道210)沿线、东西(凯麻公路、贵黄公路以及国道320)沿线大城市扩展较快,并以交通十字交点为中心形成中高速扩展区域,而且这种由节点城镇向轴线发展的趋势表现日益突出。(3)从扩展强度等级上看,存在扩展强度等级逐渐递增的规律,即由低速扩展→低中速扩展→中速扩展→中高速扩展→高速扩展。道路等级与城镇扩展强度成正比例关系,即道路等级越高,其沿线城镇土地利用扩展强度越大;经济是城镇扩展的重要影响因素,经济的快速增长能提高城镇扩展强度;平坦开阔的地形地貌将利于城镇扩展,而山高坡陡等崎岖的地形地貌将阻碍城镇的扩展。      

Worldwide distribution of polyclyclic aromatic hydrocarbons in urban road dust

Polycyclic aromatic hydrocarbons (PAHs) are considered as one of the most important groups of organic environmental contaminants due to their toxicity, persistence and ubiquity. PAHs have been monitored in urban road dust at various locations worldwide in about last three decades. Resuspension of road dust containing PAHs is an important route of human exposure to PAHs. This paper collates the available information on reported concentrations of PAHs in urban road dust at various worldwide locations classified as industrial, residential, traffic, city and commercial and other areas, reported sources of PAHs and related interpretations. The available information has been reviewed and documented country-wise. Variation in PAHs concentrations over various worldwide locations have been scrutinized, and interestingly, most of the reported average PAHs concentrations were found to be distributed within a very narrow range of values, implying only little variation in average PAH concentrations in spite of great distances between locations, climatic variation and differences in anthropogenic activities.     

Comparison of magnetic parameters with vehicular Br levels in urban roadside soils

Chemical methods are generally chosen to monitor soil pollution but magnetic measurements proved to yield additional information at low cost and less time consumption. In this investigation, the novel use of rapid and non-destructive magnetic measurements to characterize Br levels in Xuzhou (China) urban roadside soils was reported. X-ray fluorescence spectrometry (XRF) was used to quantify Br in the soil samples. Data from 21 roadside soil samples confirm Br contamination, with a mean level of 4.36 mg kg⁻¹ and a range of 2.4–8.7 mg kg⁻¹. These values are higher than that of unpolluted soils in Xuzhou that averages 1.1 mg kg⁻¹. Hierarchical clustering analysis shows Br in Xuzhou roadside soils is mainly from road traffic. Clear correlations between Br levels and simple magnetic parameters [mass specific susceptibility (χ _LF), susceptibility of anhysteretic remanent magnetization (χ _ARM), saturation isothermal remanence (SIRM)] are observed. The present study shows that these three magnetic parameters can be used as a proxy for Br levels in Xuzhou urban roadside soils.     

Spatio-temporal analysis of road traffic accident fatality in Bangladesh integrating newspaper accounts and gridded population data

Road traffic accidents pose serious threats to human lives and often cause premature deaths, disabilities, and socioeconomic impacts. The objective of this study is to analyze the fatal road traffic accidents in Bangladesh by performing a space–time characterization of fatality rates involving an innovative newspaper-based method in concert with gridded population data to construct a road traffic fatality database. Kernel density estimation, temporal data plots and space–time pattern mining tools that combine the Getis-Ord Gi* statistic with the Mann–Kendall test are used to describe spatio-temporal hotspots/coldspots and trends. Results show different patterns between the urban and rural areas of Bangladesh and higher rates of road traffic accidents occur in the metropolitan regions (Dhaka) and in a northern region centered on Sirajganj area. Most of the road traffic accidents took place in between 9:00 and 12:00 pm while the accident rates remain low between 12:00 and 3:00 am. Spacetime analysis results reveal a core region of persistently high rates along with four smaller regions with high and intensifying rates. The output of this study could be useful to reduce road traffic fatalities, injuries, increase awareness, and adopt necessary interventions for public safety through integrating both the local, regional, and central level decision makers of public transportation policy and issues in Bangladesh. The approach has potential to be translated to other developing countries.     

Assessment of noise exposure and associated health risk in school environment

Noise exposure has become one of the most important factors in determining the quality of life in indoor environments. This paper assesses and analyzes noise exposure levels at school and preschool classrooms with different indoor environments. The sound level [A-weighting equivalent steady sound level L _Aeq (dBA)] was measured using a CEL-63× digital sound level meter. The noise level measurements were performed inside two preschools at three classrooms (an activity room, classroom KG1 and classroom KG2) and three schools at different classrooms, starting from grade 1 to grade 12. The logarithmic average noise levels (L _{Aeq avg}) and the 8-h average noise exposure level (L _{EX, 8-h}) were estimated for each classroom. Furthermore, health risk issues associated with the exposure to high noise levels were investigated using a questionnaire and an interview with more than 250 teachers at the preschools and the schools. Then, the results were analyzed using different statistical tools and were compared with the World Health Organization, Occupational Health and Safety and National Institute for Occupational Safety and Health standards. Also, the results were compared with those from different countries worldwide. The study results show that the 8-h average noise exposure level exceeded the allowable limits in some schools, which indicates that students and teachers can face a serious health effects from noise exposure. The comparisons show that the values of noise levels in Kuwait are higher than those in different countries. The maximum value of noise levels was found in secondary schools. The health problems found during the survey are potentially associated with issues related to hearing, voice, headache and the physiological function of teachers.     

Sediment-water column exchange of persistent organic pollutants (PAH<Subscript>s</Subscript> and PCB<Subscript>s</Subscript>) and their transport vector in El Bey watershed,Tunisia

El Bey river, which drains 60% of the pollutant load of several urban cities in the northeast of Tunisia, provides a good example of the transfer of organic and metallic pollutants that result from industrial and urban activity, and can be used to show how these charges are transported and discharged into the Gulf of Tunis. Persistent organic pollutants (PAH and PCB) in dissolved, particulate matter, bed sediments, and three wastewater effluents in El Bey watershed were analyzed. PAH (∑14PAHs) concentration ranged from 0.248 to 9.955 mg L^?1 and from 0.836 to 28.539 mg L^?1 in dissolved and particulate fraction respectively. The particulate/dissolved partition coefficient value (Kd) was less than one which confirmed the affinity of PAH to be adsorbed. In sediment, the high-molecular weight PAHs were found principally with percentage between 50 and 100% witch present 239.99 to 5362.19 μg kg^?1, which is relatively higher in comparison with other estuaries river. Contrary to PAH patterns, PCB were bound to dissolve fraction. Kd _(PCB) value (Kd?>?1) reflected this affinity which is related to environment energy. The spatial distribution and profile of analyzed organic pollutants confirmed the direct impact of wastewater effluent on the organic pollution level in three compartment of El Bey watershed and his profiles suggested different transport patterns.     

Contamination and potential mobility assessment of heavy metals in urban soils of Hangzhou,China: relationship with different land uses

Concentration and distribution of heavy metals (Cd, Cu, Pb and Zn) in urban soils of Hangzhou, China, were measured based on different land uses. The contamination degree of heavy metals was assessed on the basis of pollution index (PI), integrated pollution index (IPI) and geoaccumulation index (I _geo). The 0.1 mol l⁻¹ HCl extraction procedure and gastric juice simulation test (GJST) were used to evaluate the potential mobility and environmental risk of heavy metals in urban soils. The average concentration of Cd, Cu, Pb and Zn in urban soils was measured at 1.2 (with a range of 0.7–4.6), 52.0 (7.4–177.3), 88.2 (15.0–492.1) and 206.9 (19.3–1,249.2) mg kg⁻¹, respectively. The degree of contamination increased in the order of industrial area (IA) > roadside (RS) > residential and commercial areas (RC) > public park and green areas (PG). The PIs for heavy metals indicated that there is a considerable Cd, Cu, Pb and Zn pollution, which originate from traffic and industrial activities. The IPI of these four metals ranged from 1.6 to 11.8 with a mean of 3.5, with the highest IPI in the industrial area. The assessment results of I _geo also supported that urban soil were moderately contaminated with Cd and to a lesser extent also with Cu, Pb and Zn. The IP and I _geo values reveal the pollution degree of heavy metal was the order of Cd > Pb > Zn ≈ Cu. It was shown that mobility and bioavailability of the heavy metals in urban soils increased in the order of Cd > Cu > Zn ≈ Pb. Owing to high mobility of Cd and Cu in the urban soils, further investigations are needed to understand their effect on the urban environment and human health. It is concluded that industrial activities and emissions from vehicles may be the major source of heavy metals in urban contamination. Results of this study present a rough guide about the distribution and potential environmental and health risk of heavy metals in the urban soils.     

Ecological model analysis of respiratory health risk factors by ambient air pollution in Lucknow,the capital City of Uttar Pradesh,India

Ambient air pollution, particularly in the urban environment of developing countries, has turned out to be a major health risk factor. We explore the compounded impact of age sensitivity, exposure, poverty, co-morbidity, etc., along with composite air pollution in determining morbidity and health burden of people in Lucknow, India. This cross-sectional study is confined to analyse respiratory health status across different socio-economic and geographic locations using n = 140 in-depth questionnaire method. We used mean daily ambient air pollution data of PM₁₀, PM_2.5, SO_2, and NO₂ for the 2008–2018 period. We used the ecological model framework to assess the risk at different hierarchical levels and compounded severity on a spatial scale. We also used Logistic regression model with log odds and odds ratio to analyze the association of risks outcomes with composite air pollution scores calculated using the principal component analysis method. There is a strong association of location-specific respiratory disease prevalence with an overall 32 percent prevalence. The prevalence of ecological model 1 (individual domain) is 4.3 percent, while ecological model 2 (community domain) has the highest prevalence at 32.4 percent. The logistic regression model shows that respiratory disease load is positively associated with age sensitivity (P < .001) and composite pollution level (P < .001). For another model with suffocation as the outcome variable, composite pollution level (P < .001) and exposure (P < .001) are positively associated. Optimum interventions are required at Ecological models 1, 2, and 3 levels for better respiratory health outcomes.

     

N-Alkanes and polycyclic aromatic hydrocarbons (PAHs) profile of soil from some polluted sites in Niger Delta, Nigeria

Soil samples were collected at different locations from Etche and Obio Akpor local government area (LGA) of River State in Niger Delta. The n-alkane and polycyclic aromatic hydrocarbons were determined qualitatively and quantitatively using GC-FID. The concentration of PAHs in the soil samples ranged from 7.40 to 78.3 ng/g. The highest concentration of PAHs was recorded in Agbada 1 flow station, while the lowest concentration was recorded in Agbada 2 flow station. A significant level of pollution was also observed in the soil of Bomu pipeline at Obio Akpor LGA. Also, the distribution of n-alkanes in the samples was also used to assess the level of pollution in the studied area. Various n-alkanes and PAHs ratios were obtained to know the major source of pollution in the area under study. The main source of pollution was pyrolytic, which might be due to the gas flaring activities going on in the study area. Also, the results showed that n-alkanes could also be a complementary tool in assessing pollution and source apportionment.     

Pine (Pinus Eldarica Medw.) needles as indicator for heavy metals pollution

In this study, the pine tree (Pinus Eldarica Medw.) needles were evaluated as the biomonitors of heavy metal contamination in Tehran, Iran. The pine needle samples supplied from the old trees according to the main wind direction (highest wind speed) were obtained from each parts of tree and then were homogeneously mixed. The samples were taken from different locations with different degrees of metal pollution (urban, industrial, highway and control sites). Then, the concentrations of lead, zinc, copper, nickel and chromium were measured using a flame atomic absorption spectrophotometer. The result of this study showed that the highest and the lowest metal concentrations were found in the heavy traffic sites and the control site, respectively. However, samples taken from highway sites contained the high concentrations of nickel, copper and lead. Moreover, industrial areas were found to have high contents of zinc and chromium. The variation in heavy metal concentrations between the studied locations is due to changes in traffic density and anthropogenic activities. This research proved significant correlations between the heavy metal concentrations in pine needle samples. Finally, it is concluded that Pinus Eldarica Medw. needles can be applied to monitor polluted sites.     

Stream chloride concentrations as a function of land use: a comparison of an agricultural watershed to an urban agricultural watershed

The concentration of chloride (Cl^?) in streams in northern regions has increased as a result of applications of deicers. This study focused on quantifying the relationship between land use and stream Cl^? concentrations. The study area comprises two adjacent watersheds in central Illinois, with similar geology and climate but different land uses (agricultural and urban). GIS analysis delineated watershed land use and calculated road surface areas. Stream water samples were collected and analyzed for anionic composition. During the winter months, streams dominated with urban land use experienced a 20-fold increase in Cl^? concentrations (range between 36 and 1350 mg L^?1); Cl^? concentrations in agricultural dominated streams also increased, but the increase was smaller (3X) and concentrations remained low (between 11 and 58 mg L^?1). As road salts are not the sole source of Cl^? in a stream, Cl^? and bromide (Br^?) mass ratios (Cl/Br) and Cl^? and sodium (Na) molar ratios ([Cl]/[Na]) were used to identify potential sources of Cl^?. The ratios indicate urbanized watersheds were impacted by road salts; agricultural watersheds ratios indicate other anthropogenic sources. A nonlinear relationship between urban land use and stream Cl^? concentrations indicates urban land use as low as 23% results in elevated Cl^? concentrations (greater than 150 mg L^?1) in stream waters.     

Tree-ring growth recovers,but δ13C and δ15N do not change,after the removal of point-source air pollution: a case study for poplar (Populus cathayana) in northwestern China

Pollution from urban centers and fossil fuel combustion can decrease forest growth and interfere with physiological processes. To evaluate whether tree growth and the carbon isotope ratio (δ¹³C) and nitrogen isotope ratio (δ¹⁵N) in tree rings can serve as proxies for air pollution, this study compared these indices for poplar (Populus cathayana) growing at urban and suburban locations in Lanzhou, in northwestern China. Basal area increment values were much lower at the urban site than in the suburbs from 1985 to 2009, were negatively correlated with NO₂ (r = ?0.56, p < 0.01) and SO₂ (r = ?0.52, p < 0.05) emissions from 1990 to 2009, and increased abruptly after the Lanzhou urban steel factory closed. Urban tree-ring δ¹³C values were not significantly correlated with NO₂ and SO₂ concentrations, and did not differ significantly between the two sites, indicating that other environmental effects (such as precipitation) masked the pollution effects. Tree-ring δ¹⁵N values in the urban samples were much higher than the suburban values. Such differences may be attributable to uptake of ¹⁵N-enriched compounds caused by a higher urban N deposition rate. Tree growth is a promising tool for detecting ecophysiological responses of trees to both diffuse and point-source air pollution, but δ¹³C and δ¹⁵N in poplar were not sensitive to point-source air pollution in a heavily polluted environment.     

Low-field magnetic susceptibility: a proxy method of estimating increased pollution of different environmental systems

 A need for rapid and inexpensive (proxy) methods of outlining areas exposed to increased pollution by atmospheric particulates of industrial origin caused scientists in various fields to use and validate different non-traditional (or non-chemical) techniques. Among them, soil magnetometry seems to be a suitable tool, at least in some cases. This method is based on the knowledge that ferrimagnetic particles, namely magnetite, are produced from pyrite during combustion of fossil fuel. Besides the combustion processes, magnetic particles can also originate from road traffic, for example, or can be included in various waste-water outlets. Magnetite, Fe₃O₄, ranks among the main ferrimagnetic minerals and its identification in various ecosystems can contribute to fast and simple outlining of areas and sites exposed to higher pollution impact. Here the method of magnetic mapping of anthropogenic pollution will be introduced using a review of our recent case studies on different ecosystems in the Czech Republic and Germany. Received: 20 June 1998 · Accepted: 9 November 1998     

Comparison of different methods for assessing heavy metal contamination in street dust of Xianyang City, NW China

Street dust is one of the important indicators that reflect the status of urban environmental pollution. There are many studies of heavy metals contamination of street dust in capital cities; however, little attention has been paid to this kind of study in medium cities, including China. The dust samples were collected in the district of traffic crossroads in Xianyang city, Shaanxi Province. Pb, Cd, Cu, Ni, Zn, Cr and Mn concentrations were determined using atomic absorption spectrometry (AAS). The results indicate that the concentrations of heavy metals are higher than the background values of soils in Shaanxi Province. The contamination level of heavy metals is assessed by potential ecological risk index (E _r), geoaccumulation index (I _geo), enrichment factor (EF) and pollution index (Pi). The low I _geo, EF, E _r, Pi and PI_n (integrated pollution index) for Mn in street dusts indicate an absence of distinct Mn pollution. The high EF, Pi and PI_n of Cu and Zn indicate that there is considerable Cu and Zn pollution. It is suggested that more attention should be paid to heavy metals contamination of Cu and Zn. The assessment results of Pi and PI_n suggest that Pb, Ni and Cr present strong pollution; however, their EFs indicate that they cause moderate pollution and their I _geo indicates that they are unpolluted to moderately polluted. The contamination class value with different assessing methods is of the order: Pi ≈ PI_n > EF > I _geo > E _r.