关于建立城市声环境自动监测系统的设想

文章以随机过程“各态历径”理论说明了“定点测量法”与“网格测量法”的内在联系 ,提出了以城市建成区内各类不同环境功能区为基础进行城市声环境自动监测系统监测点位布设的技术规范设想。     

Locating air quality monitoring station using wind impact area diagram

In this study a new methodology is suggested to approximate the impact area downwind of an air pollution source, where air quality monitoring can be carried out to capture the maximum pollutant concentration. Hourly wind speed for a given month is grouped in to different wind speed ranges and the distance of pollutant travel is approximated from the average wind speed of that wind speed range. Since change in wind direction causes the impact distance to rotate, its rotation is approximated by the SD of wind direction change. Using this approach, area or region down wind of a source is determined and plotted. The pattern of monthly change of wind is better represented by the new type of diagram as compared to the wind rose diagram.     

Quality control and quality assurance for particle size distribution measurements at an urban monitoring station in Augsburg, Germany

Long-term observations of atmospheric constituents such as aerosol particles are increasingly needed to assess their impact on climate and human health. In contrast to particle mass concentration (MC), there are currently no standardized quality control (QC) and quality assurance (QA) procedures for the measurement of particle size distribution (PSD). This study describes some fundamental QC and QA procedures associated with the collection and evaluation of a 2 year dataset between 2005 and 2006 at an urban background monitoring site in Augsburg, Germany. The considered parametres include ambient PSD between 3 nm and 10 microm (merged from a twin differential mobility and an aerodynamic particle sizer, TDMPS and APS, respectively) as well as total particle number (TNC), length (LC) and MC determined by independent instruments. The hourly 1st and 0th moment of PSD showed good correlations with the independently measured LC (R(2) = 0.86) and TNC (R(2) = 0.79), respectively, the deviation for LC with 4% and for TNC with 22% being rather small. The volume concentration (3rd moment) of hourly measured PSD and the resultant MC (when assuming a realistic apparent density of 1.5 g cm(-3)) correlated well with the independently measured MC of PM(2.5) or PM(10) (R(2) > 0.86) and showed only small deviation from PM(2.5) (1%) or PM(10) (5%), respectively. The study demonstrates that the described QC and QA measures define both a high accuracy of the PSD measurements and their long-term comparability against data obtained in similar measurement programmes.     

Using a neural network approach and time series data from an international monitoring station in the Yellow Sea for modeling marine ecosystems

The international marine ecological safety monitoring demonstration station in the Yellow Sea was developed as a collaborative project between China and Russia. It is a nonprofit technical workstation designed as a facility for marine scientific research for public welfare. By undertaking long-term monitoring of the marine environment and automatic data collection, this station will provide valuable information for marine ecological protection and disaster prevention and reduction. The results of some initial research by scientists at the research station into predictive modeling of marine ecological environments and early warning are described in this paper. Marine ecological processes are influenced by many factors including hydrological and meteorological conditions, biological factors, and human activities. Consequently, it is very difficult to incorporate all these influences and their interactions in a deterministic or analysis model. A prediction model integrating a time series prediction approach with neural network nonlinear modeling is proposed for marine ecological parameters. The model explores the natural fluctuations in marine ecological parameters by learning from the latest observed data automatically, and then predicting future values of the parameter. The model is updated in a “rolling” fashion with new observed data from the monitoring station. Prediction experiments results showed that the neural network prediction model based on time series data is effective for marine ecological prediction and can be used for the development of early warning systems.     

区域环境噪声标准适用区域划分的定量化

根据国家环保局关于区域环境噪声环境划分的规定，提出了区域环境噪声标准定量化划分的模型，该模型综合了自然因素和噪声污染因素，模型在南通市区域环境噪声标准划分中得到了验证。     

Instability in a small hypereutrophic urban lake

Two summer intensive monitoring programs were conducted on a small Louisiana urban lake following restoration. Monitoring objectives were directed towards providing high resolution data needed to examine lake temporal and spatial variability. During the first year of post-restoration (1983), anaerobic conditions developed in the lake and a major fish kill (Ictalurus sp.) was observed. Total phosphorus concentrations at stations nearest the lake bottom were exceedingly high (>0.400 mg L^–1), suggesting the source of phosphorus was sediment release. Monitoring conducted in 1984 indicated the re-establishment of high benthic demand and internal nutrient recycling patterns. Mean phosphorus levels increased by more than 50% over the observed 1983 values, while dissolved oxygen concentrations demonstrated gradients from surface to bottom and were consistently below 2.0 mg L^–1 in the bottom waters.     

Assessing health risk from benzene pollution in an urban area

A health hazard, specifically the leukaemia risk, is evaluatedfrom different sources of benzene exposure with relation to apopulation living in an urban area of Italy. The population exposure is calculated for a reference year by sexand lyfestyle, with respect to smokers and non smokers. Potentialhealth risk is therefore quantified by means of mathematicalmodels and the relative significance of the different sources is described. The results of the analysis are useful for the identification ofappropriate risk reduction strategies to minimize exposure, inparticular when resulting from lifestyle and personal activities.     

Fate of selenium in a small urban watershed

A field study was conducted on a small urban watershed (residential and golf course dominated) in southern Nevada to assess the concentration and speciation of selenium (Se) in a series of drain lines and monitoring wells and to quantify the mass discharge of Se from the drain system. Water samples were collected on a monthly basis and analyzed for total Se, selenate (SeO₄ ⁼) and selenite (SeO₃ ⁼). In addition, where possible, flow was assessed as was, temperature, redox potential, pH, dissolved oxygen (DO) along with all major cations and anions. The data were then modeled with PhreeqC to identify selenium speciation. Results revealed a SeO₄ ⁼ dominated system with SeO₄ ⁼ concentrations ranging from 13 to 62 ppb. In the monitoring wells, 66 % of the variation in the total Se concentration could be described based on depth to groundwater, temperature and sulfate concentrations (P?<?0.001). In particular, higher total Se concentrations were predicted for shallower depth to groundwater, suggesting the solubilization of Se evapo-concentrates near the surface could be reduced by lowering water tables. The highest of all correlations was found between SeO₄ ⁼ concentrations (↑) and the sodium (↑) and DO (↑) concentrations in the monitoring wells (R ²?=?0.77, P?<?0.001). An excellent curvilinear relationship was found between total Se and the electrical conductivity in the water (R ²?=?0.73, P?<?0.001). Based on the Se data and time line identified in this study, high concentrations of Se could be expected to drain from this area for many years to come, with salinity acting as a good proxy for Se concentration. In the drain lines, Se concentrations were found to be invariant to flow (P?>?0.05). Flow discharge from the main drain system to the Las Vegas Wash was estimated at 559 acre feet during the 1 year study period. This flow was estimated to carry 4,203 Mg of salts 6.71 Mg of nitrate-N and 27.1 kg of total Se.     

Investigation of the aerosol structure over an urban area using a polarization lidar

The paper presents a lidar study of the aerosol structure in the planetary boundary layer in the case of radiation fog and haze. A conceptual model of the dynamics of the depolarization coefficient profile during the mixing layer development, taking into account the presence of a multilayered inversions and radiation fogs, is proposed. Various techniques are employed in the processing of the lidar signal in order to determine the mixing layer height as well as more details of the aerosol structure in the low atmosphere, namely, finding the maximum of the signal returned from the lowest temperature inversion, the crossing point of the S function's first derivative with the x axis, and profiles of the depolarization ratio. After the complete destruction of the stable stratification, a low constant value of the depolarization ratio within the newly formed mixing layer is being observed. The study of stable boundary layer disintegration and convective boundary layer formation in the presence of fogs and/or clouds is of both scientific and practical significance in what concerns the protection of the environment and the aviation meteorology.     

Evaluation and optimization of an urban PM2.5 monitoring network

The objective of this study was to evaluate the PM(2.5) monitoring network established in the Greater Cincinnati and Northern Kentucky metropolitan area for measuring the 24 h integrated PM(2.5) concentration, as well as-at selected sites-hourly PM(2.5) concentration and 24 h integrated PM(2.5) speciation. The data collected during three years at 13 measurement sites were analyzed for spatial and temporal variations. It was found that both daily and hourly concentrations of PM(2.5) have low spatial variation due to a regional influence of secondary ammonium sulfate. In contrast, the trace element concentrations had high spatial variation. Seasonal variation accounted for most of the total temporal variation (60%), while yearly, monthly, weekly and daily variations were lower. The variance components and cluster analyses were applied to optimize the number of sites for measuring the 24 h PM(2.5) concentration. It was found that the 13-site network may be optimized by reducing the number of sites to 8, which would result in a relative precision reduction of 9% and a relative cost reduction of 36%. At the same time, the data suggest that the spatial resolution of speciation monitors and real-time PM(2.5) mass monitors should be increased to better represent spatial and temporal variations of the markers of local air pollution sources.     

Measurements of semivolatile and particulate polycyclic aromatic hydrocarbons in a bus station and an urban tunnel in Salvador,Brazil

Motor vehicles constitute a significant source of polycyclic aromatic hydrocarbon (PAH) emissions to the atmosphere. Particle-phase priority pollutant PAH concentrations and total suspended particle mass (TSP) were measured in the Lapa bus station and the Americo Simas Tunnel, located in the city of Salvador, Brazil. Separate samples were collected at the bus station at different times of the day, including rush- and non-rush-hour periods. The highest concentrations for nearly all 16 priority PAHs measured at the bus station were observed at 18:30 h, with chrysene showing the highest mean value (26.6 ng m-3). The highest average PAH concentrations measured in the tunnel were observed for pyrene (79.4 +/- 11.5 ng m-3) followed by fluoranthene (39.0 +/- 5.2 ng m-3) and chrysene (28.0 +/- 4.17 ng m-3). TSP levels reached 423 micrograms m-3 in the bus station, and values as high as 2 mg m-3 in the tunnel. The measured Salvador tunnel PAH profiles are very similar to the Salvador bus station profiles, and are similar to PAH profiles reported for the Kojouike Tunnel, located in Kurashiki City, Japan, and the Caldecott Tunnel, located in Berkeley, California.     

Air quality assessment of Estarreja, an urban industrialized area, in a coastal region of Portugal

Despite the increasing concern given to air quality in urban and industrial areas in recent years, particular emphasis on regulation, control, and reduction of air pollutant emissions is still necessary to fully characterize the chain emissions–air quality–exposure–dose–health effects, for specific sources. The Estarreja region was selected as a case study because it has one of the largest chemical industrial complexes in Portugal that has been recently expanded, together with a growing urban area with an interesting location in the Portuguese coastland and crossed by important road traffic and rail national networks. This work presents the first air quality assessment for the region concerning pollutant emissions and meteorological and air quality monitoring data analysis, over the period 2000–2009. This assessment also includes a detailed investigation and characterization of past air pollution episodes for the most problematic pollutants: ozone and PM10. The contribution of different emission sources and meteorological conditions to these episodes is investigated. The stagnant meteorological conditions associated with local emissions, namely industrial activity and road traffic, are the major contributors to the air quality degradation over the study region. A set of measures to improve air quality—regarding ozone and PM10 levels—is proposed as an air quality management strategy for the study region.     

Polycyclic aromatic hydrocarbons (PAHs) in atmospheric urban area: monitoring on various types of sites

The air quality over the Toulouse urban area (France) is recorded daily by the regional "Midi-Pyrénées" atmospheric pollution measurements network (ORAMIP). Relevant data is collected from about 100 analysers spread over more than thirty stations. The regulations covering major indicators of atmospheric pollution (ozone, nitrogen dioxide, sulphur dioxide) have been updated in recent years to include additional compounds like polycyclic aromatic hydrocarbons (PAHs). The ORAMIP, in partnership with the ENSIACET has undertaken background PAH average concentration measurements over the urban agglomeration of Toulouse during spring 2006 for various types of sites (traffic, urban, industrial). The sampling was performed using a low volume air sampler equipped with quartz fiber filters and polyurethane foams For the two urban sites, total atmospheric concentrations between 12 and 20 ng/m(3) have been obtained, whereas for the industrial site the values averaged 22 ng/m(3). In addition, and regardless of site, the average concentrations of benzo[a]pyrene, at present the only regulated PAH, were always less than the 1 ng/m(3) limit.     

苏州市区大气监测点位调整中的相关性和聚类分析

根据苏州市8个国控大气监测站点2013—2015年的PM_(10)、PM_(2.5)、O_3、SO_2监测数据,计算了各站点之间监测数据的相关系数;通过分析相关系数矩阵,发现苏州市大气国控点位的监测数据相关性均较高,点位设置存在一定的冗余,国控监测点位的优化调整十分必要。利用最长距离法对各站点的监测数据进行聚类分析,从而得出中心城区的点位调整方案。点位调整前后4种污染物监测数据四季平均值的相对误差均小于5%;正负偏差的二项检验结果表明,调整后未对监测结果产生显著的正/负影响。因此,经过优化的大气监测网络具有较好的客观性和代表性。     

电视台卫星地面站电磁辐射对城市其它微波站的干扰分析

通过理论分析计算 ,掌握电视台卫星地面站电磁辐射对城市其它微波站的干扰情况 ,为此类电磁辐射源环境影响管理提供参考性意见     

工业企业噪声监测工作中几个难点问题的探讨

通过举例对噪声监测实践工作中常易遇到的几个具有普遍性的难点问题作一探讨,以提高大家在解决实际问题时对声学理论、噪声标准及测量方法的重视。     

Sources of potentially toxic elements and organic pollutants in an urban area subjected to an industrial impact

Urban and industrial development has caused a major impact on environmental soil quality. This work assesses the extent and severity of contamination in a small urban area subjected to an industrial impact and identifies the major anthropogenic inputs. Twenty-six soil samples were collected from agricultural and urban sites, and concentrations of potentially toxic elements (As, Cd, Cu, Cr, Fe, Mn, Ni, Pb and Zn), PAHs and PCBs, were determined. In spite of the low median concentrations observed, some sites represent a potential hazard for human health and ecosystems. Concentrations of contaminants were higher than those found in a nearby city, indicating that the study area is affected by the surrounding industry. The use of multivariate statistical analyses allowed for the identification of the main factors controlling the variability of potentially toxic elements and organic pollutants in the soils. The presence of Cr, Fe, Mn and Ni was associated with geogenic inputs, and Cu, Pb, Zn, As, PAHs and PCBs were associated with anthropogenic inputs. Industry and traffic were the most important anthropogenic sources. Soil characteristics were identified as important factors controlling the spatial variability of elements, both from recognised natural and anthropogenic origin. Differences between land uses were observed, which may be attributed to both management practices and proximity to sources.     

Co-assessment of biomass and soil organic carbon stocks in a future reservoir area located in Southeast Asia

An assessment of the organic carbon stock present in living or dead vegetation and in the soil on the 450 km² of the future Nam Theun 2 hydroelectric reservoir in Lao People??s Democratic Republic was made. Nine land cover types were defined on the studied area: dense, medium, light, degraded, and riparian forests; agricultural soil; swamps; water; and others (roads, construction sites, and so on). Their geographical distribution was assessed by remote sensing using two 2008 SPOT 5 images. The area is mainly covered by dense and light forests (59%), while agricultural soil and swamps account for 11% and 2%, respectively. For each of these cover types, except water, organic carbon density was measured in the five pools defined by the Intergovernmental Panel on Climate Change: aboveground biomass, litter, deadwood, belowground biomass, and soil organic carbon. The area-weighted mean carbon densities for these pools were estimated at 45.4, 2.0, 2.2, 3.4, and 62.2 tC/ha, respectively, i.e., a total of about 115 ± 15 tC/ha for a soil thickness of 30 cm, corresponding to a total flooded organic carbon stock of 5.1 ± 0.7 MtC. This value is much lower than the carbon density for some South American reservoirs for example where total organic carbon stocks range from 251 to 326 tC/ha. It can be mainly explained by (1) the higher biomass density of South American tropical primary rainforest than of forests in this study and (2) the high proportion of areas with low carbon density, such as agricultural or slash-and-burn zones, in the studied area.     

Particle-bound polycyclic aromatic hydrocarbons in an urban, industrial and rural area in the western Mediterranean

Particle-bound PAHs were measured at three sites in southeastern Spain (an urban background location, a suburban-industrial site in the vicinity of two cement plants and a rural area) in order to investigate the influence of the type of location on PAH concentrations. A clear influence of cement production on particulate PAH levels could not be established since for the urban background and suburban-industrial sites the average concentrations of total PAHs in the PM2.5 fraction were very similar (1.085 and 1.151 ng m(-3), respectively), with benzo[b+k]fluoranthene and chrysene as the predominant compounds. Diagnostic ratios, used to identify PAH emission sources, pointed to traffic as the main source of particulate PAH at both locations. As expected, PAH levels at the rural site were significantly lower (0.408 ng m(-3) in the PM10 fraction) due to increasing distance from the emission sources. PAH seasonal variations at the urban background and suburban-industrial sites were the same as reported in many previous studies. Average winter to summer ratios for total PAHs were 4.4 and 4.9 for the urban background and industrial sites, in that order. This seasonal cycle could be partially explained by the higher temperature and solar radiation during summer enhancing PAH evaporation from the particulate phase and PAH photochemical degradation, respectively. The study of PAH distribution between the fine and coarse fraction at the urban site revealed that on average around 80% of total PAHs were associated with fine particles.