Modelling the environmental behaviour of pollutants in Algeciras Bay (south Spain)

An environmental study of Algeciras Bay is carried out through numerical modelling. First, a 2D barotropic model is applied to calculate tides and mean circulation. Results of this model are used by a sediment transport model which provides suspended matter concentrations and sedimentation rates in the Bay. It includes three particle classes. An effective diffusion coefficient has been calibrated simulating temperature distribution inside the Bay. An additional validation is obtained from an independent nitrate dispersion simulation. Then heavy metal dispersion patterns are investigated using a model which includes water-sediment metal interactions and uses the outputs of the hydrodynamic and sediment transport models. The metal transport model has been applied to simulate the dispersion of Zn, Cu and Ni. Results from the hydrodynamic, sediment and metal transport models have been compared with measurements. Model results also indicate that transport inside the Bay is relatively weak. Numerical experiments have been carried out to determine flushing times for conservative and non-conservative pollutants. Flushing time is about 20 days for a conservative tracer, and this value is mainly due to the M(2) residual current. Tides are not effective in removing pollutants.     

Modeling the Effects of Meteorological Factors on SO2 and PM10 Concentrations with Statistical Approaches

Air quality has been deteriorated seriously in urban areas as a result of increasing anthropogenic activities. Meteorological conditions affect air pollution levels in the urban atmosphere significantly due to their important role in transport and dilution of the pollutants. This paper aims to investigate usability of some promising statistical methods for examining the impacts of metrological factors on SO₂ and PM10 levels. Data were collected from city centre of Kocaeli in winter periods from 2007 to 2010 as pollutant concentrations increase in winters due to expanding combustion facilities. Results of bivariate correlation analysis showed that humidity and rainfall have remarkable negative correlations with the pollutants. Multiple linear regression models and artificial neural network (ANN) models were used to predict next day's PM10 and SO₂ levels. In regression models calculated R² values were 0.89 and 0.75 for PM10 and SO₂, respectively. Among the various architectures, single layer networks provided better performance in ANN applications. Highest R² values were obtained as 0.89 and 0.69 for PM10 and SO₂, respectively, by using appropriate networks.     

Impact of clean air action on PM2.5 pollution in China

<正>China suffers from severe air pollution in the past decades,characterized by high-levels of fine particulate matter(PM_(2.5)) concentrations. To mitigate PM_(2.5) pollution, the Chinese government issued the Air Pollution Prevention and Control Action Plan (referred to as the Clean Air Action hereinafter) in 2013, which requires the three key regions,     

中国清洁空气行动对PM2.5污染的影响

随着经济快速发展,中国近十年来大气污染事件频发,严重危害居民公共健康.为应对严重的大气污染问题,切实改善空气质量,国务院于2013年颁布了《大气污染防治行动计划》(简称《大气十条》)(国务院, 2013),要求到2017年全国地级及以上城市可吸入颗粒物(PM10)年均浓度比2012年下降10%以上,优良天数逐年提高。     

Improved water quality in response to pollution control measures at Masan Bay, Korea

The total pollution load management system (TPLMS) was first applied in 2007 to the highly developed Masan Bay watershed, Korea. To evaluate the effect of TPLMS on water quality improvement, we analyzed the water qualities in rivers and bay during 2005-2010, targeting chemical oxygen demand (COD), suspended sediment (SS), total nitrogen (TN), and total phosphorus (TP) loads. Land-based pollutant loading all decreased during this period, with a significant reduction in COD and SS loads (p<0.01). The COD reduction in seawater, following the TPLMS implementation, was also significant (p<0.01). Time-lagged responses in COD and Chl-a supported an estimated seawater residence time of ~1 month. Land-based nutrient loads were also significantly reduced for TN (p<0.01) and TP (p<0.05), however, significant reductions were not observed in the bay, indicating potential alternative nutrient inputs from non-point sources into the bay system.     

PM10 in the atmosphere and incidence of respiratory illness in Chiangmai during the smoggy pollution

Adverse health effects of atmospheric exposure to particles have been described in numerous epidemiological studies. In early of March 2007, there was a big environmental crisis in the northern area of Thailand. Smoggy pollution due to the fires covered many provinces in this area. Here, the author analyzes the correlation on incidence of respiratory illness and PM10 level in Chiangmai, a province in northern Thailand where the pollution occurred. The finding of emerging of the respiratory illness is similar to those previous reports on other smoggy pollutions due to fires. However, there is not a direct statistical significant relationship. It is proved that PM10 might be a risk for respiratory illness attack.     

Finding regions of influence on SO2 and SO= 4 daily concentration measurements at four sites in Spain

Contamination by the pollutants SO₂ and SO⁼₄ was analyzed for the 1989–1992 period at four regional stations in Spain under the auspices of the EMEP-BAPMON program. The evolution of the time series of the daily pollution has also been assessed, and high mean concentrations at La Cartuja and Logroño observed, with values of 3.8 and 4.5 g m⁻³ for SO₂, respectively. Maximum annual concentrations were recorded in 1989, when SO₂ reached values of 6.24, 5.39, 5.71, and 9.30 g m⁻³ for the stations of La Cartuja, San Pablo de los Montes, Roquetas, and Logroño, respectively. This work attempts to establish a relationship between the concentrations of the pollutants - both SO₂ gas and SO⁼₄ aerosol - and the zones of emission or persistence of these long-range transported pollutants. In this way, those regions showing a greater impact on the air quality in each season have been determined. To achieve this, the trajectories of the air masses carrying away the pollution to each of the receiving stations were considered and followed by a sectorial analysis. Nonparametric statistical methods were implemented to contrast the chemical homogeneity among the different sectors. The criterion that several homogeneous sectors form a chemically homogeneous region was used. To improve this sectorial analysis, we have proposed a new technique based on the Potential-Source-Contribution Function (PSCF). Starting out from a set of specified regions, considered to be chemically homogeneous domains, it is possible to determine the likelihood that an air mass with particular characteristics (e.g., that a value of the daily concentration higher than the mean recorded at the station has been obtained) will arrive at a given station after having crossed one of the previously defined regions. Using this technique, it is possible to determine the source regions through which the air masses circulate and bring high pollution concentrations to the studied stations. Thanks to the PSCF, these statistical methods offer, through a sectorial analysis, the possibility to pass from a qualitative to a more quantitative view.     

Average mass concentrations of TSP, PM10 and PM2.5 in Erzurum urban atmosphere, Turkey

In this study, particulate matters (TSP, PM₁₀, PM_2.5 and PM_10–2.5) which are hazardous for environment and human health were investigated in Erzurum urban atmosphere at a sampling point from February 2005 to February 2006. During sampling, two low volume samplers were used and each sampling period lasted approximately 24 h. In order for detection of representative sampling region and point of Erzurum, Kriging method was applied to the black smoke concentration data for winter seasons. Mass concentrations of TSP, PM₁₀ and PM_2.5 of Erzurum urban atmosphere were measured on average, as 129, 31 and 13 μg/m³, respectively, in the sampling period. Meteorological factors, such as temperature, wind speed, wind direction and rainfall were typically found to be affecting PMs, especially PM_2.5. Air temperature did not seem to be significantly affecting TSP and PM₁₀ mass concentrations, but had a considerably negative induction on PM_2.5 mass concentrations. However, combustion sourced PM_2.5 was usually diluted from the urban atmosphere by the speed of wind, soil sourced coarse mode particle concentrations (TSP, PM₁₀) were slightly affected by the speed of wind. Rainfall was found to be decreasing concentrations to 48% in all fractions (TSP, PM₁₀, PM_10–2.5, PM_2.5) and played an important role on dilution of the atmosphere. Fine mode fraction of PM (PM_2.5) showed significant daily and seasonal variations on mass concentrations. On the other hand, coarse mode fractions (TSP, PM₁₀ and PM_10–2.5) revealed more steady variations. It was observed that fine mode fraction variations were affected by the heating in residences during winter seasons.     

Application of MODIS satellite products to the air pollution research in Beijing

The direct correlation between NASA MODIS aerosol optical depth (AOD) products and the air pollution index (API) in Beijing was found relatively low based on the long-term comparison analysis. The correlation improved to some extent after taking account of the seasonal variation of scale height and the vertical distribution of aerosols. The correlation coefficient further improved significantly after considering the influencing factor of Relative Humidity (RH). This study concluded that satellite remote-sensing could serve as an efficient tool for monitoring the spatial distribution of particulate pollutants on the ground-level, as long as corrections have been made in the two aforementioned processes. Taking advantage of the MODIS information, we analyzed a pollution episode occurring in October 2004 in Beijing. It indicated that satellite remote-sensing could describe the formation process of the ground-level pollution episode in detail, and showed that regional transport and the topography were crucial factors to air quality in Beijing. The annual averaged distribution in the urban area of Beijing and its surroundings could be also obtained from the high-resolution retrieval results, implicating that high-resolution satellite remote-sensing might be potential in monitoring the source distribution of particulate pollutants.     

Heavy metal pollution and assessment in the tidal flat sediments of Haizhou Bay,China

The heavy metal inventory and the ecological risk of the tidal flat sediments in Haizhou Bay were investigated. Results show that the average concentrations of heavy metals in the surface sediments exceeded the environment background values of Jiangsu Province coastal soil, suggesting that the surface sediments were mainly polluted by heavy metals (Cd, Cr, Cu, Mn, Pb and Zn). In addition, the profiles of heavy metals fluxes can reflect the socio-economic development of Lianyungang City, and heavy metals inputs were attributed to anthropogenic activities. Cr, Cu, Pb and Zn were mainly present in the non-bioavailable residual form in surface sediments, whereas Cd and Mn were predominantly in the highly mobile acid soluble and reducible fractions. The ecological risk of the polluted sediments stemmed mainly from Cd and Pb. According to the Sediment quality guidelines (SQGs), however, the adverse biological effects caused by the heavy metals occasionally occurred in tidal flat.     

Correlation between plasmid DNA damage induced by PM_(10) and trace metals in inhalable particulate matters in Beijing air

Based on the study of Beijing PM10 bioreactivity with the newly developed plasmid DNA assay method, and analysis for trace elements of PM10, the cause of plasmid DNA damage by PM10 was investigated. The study showed that plasmid DNA oxidative damages by PM10 are of difference in different seasons at various areas. The concentrations of TM50 of PM10 in whole samples respectively collected at urban and comparison sites during winter were 900 μg mL?1 and 74 μg mL?1, while those in their corresponding soluble fractions were 540 μg mL?1 and 86 μg mL?1. In contrast, TM50 contents of PM10 from summer whole samples at urban areas and comparison sites were 116 μg mL?1 and 210 μg mL?1, whereas those in their soluble fractions were 180 μg mL?1 and 306 μg mL?1. The difference of bioreactivity of Beijing PM10 resulted from the variation of trace elements. The oxidative damage of plasmid DNA caused by Pb, Zn, As in PM10 (whole sample) was relatively strong. TM50 and Mn, V, Zn display stronger correlation in the soluble fraction. It implies that Zn could be the major trace element in Beijing PM10 which contributes to oxidative damage to plasmid DNA.     

Benthos abundance pattern and species composition in conditions of pollution in Amursky Bay (the Peter the Great Bay,the Sea of Japan)

Multivariate statistical analysis of data on environmental variables and benthic macrofauna, of 30 sites from four surveys done between 1986 and 1989 in Amursky Bay, is presented. The purpose of this study is to investigate a contamination gradient, assess effects on benthic fauna and evaluate quantitative and qualitative benthic parameters.Contamination was assessed using chemical data from PCA-ordination analysis. Clear patterns were found using three categories, moderate, severe and gross. Significant changes in the number of taxa, density and ecological indices are observed between severe and moderate levels. Changes in these parameters, excluding the number of species, were also detected between gross and moderate levels. Only biomass differs non-significantly. However results of cluster analysis and MDS ordination indicate that two benthic communities exist in Amursky Bay.The most "contaminant insensitive" species polychaetes are Tharyx pacifica, Dorvillea (Schistomeringos) japonica, Dipolydora cardalia, Capitella capitata, phoronid Phoronopsis harmeri. Contaminant sensitive species include Maldane sarsi, Lumbrineris sp. and Scoloplos armiger.     

Bioindication of water and bottom sediment pollution in the Kondopozhskaya Bay of Lake Onega

The situation in the Kondopozhskaya Bay of Onega Lake, polluted by wastewater of a pulp-and-paper mill is considered. The dynamics of wastewater input over 80 years is analyzed; the rate of such input varied widely in this period because of changes in cellulose production processes. A close correlation was found to exist between the characteristics of the state of aquatic organism communities and the environmental physicochemical characteristics. The pollution indices of water mass and the bed are evaluated, including biological and physicochemical data. Those indices can be used to identify polluted zones of water and bottom sediments in Onega Lake subject to the discharge of wastewaters from pulp-and-paper mill.     

Magnetic gradient map of the mine tailings in Portman Bay (Murcia,Spain) and its contribution to the understanding of the bay infilling process

The present study is a pilot magnetic gradient survey inserted in a set of geological and geophysical works that are planned to understand the infilling process of the Portman Bay (Murcia, Spain).In a period of 33 years (from 1957 until 1990) the Portman Bay has been silted up with mine tailings. This mining waste, after being discharged into the sea, was transported by littoral currents which sorted it and concentrated the densest mineral fractions (mainly magnetite and other iron oxides). In this sedimentary context, the magnetic gradient map obtained did not detect any massive accumulation of magnetic minerals, but rather a regular distribution following parallel-banded structures in the successive contours of the bay. It has been observed that one of these magnetic bands perfectly superimposes on the ancient coastline visible in aerial photo of 1972, interpreting that this coincidence is explained by the fact that the magnetite was concentrated along the sandy ridges, oriented according to the refraction of the littoral currents.In this document we analyse the magnetic gradient map obtained in a restricted sector of the Portman Bay. This sector covers an area of 2 ha and it was chosen as a first test. The significant results suggest the suitability of this method to be conducted to the whole bay. The main objective of this study is to show the usefulness of magnetic gradient method to obtain a paleogeographic reconstruction of the infilling process of this bay.     

Vertical structures of PM10 and PM 2.5 and their dynamical character in low atmosphere in Beijing urban areas

The vertical structures and their dynamical character of PM2.5 and PM10 over Beijing urban areas are revealed using the 1 min mean continuous mass concentration data of PM2.5 and PM10 at 8, 100, and 320 m heights of the meteorological observation tower of 325 m at Institute of Atmospheric Physics, Chinese Academy of Sciences (IAP CAS tower hereafter) on 10―26 August, 2003, as well as the daily mean mass concentration data of PM2.5 and PM10 and the continuous data of CO and NO2 at 8, 100 (low layer), 200 (middle layer), and 320 m (high layer) heights, in combination with the same period meteorological field observation data of the meteorological tower. The vertical distributions of aerosols observed on IAP CAS tower in Beijing can be roughly divided into two patterns: gradually and rapidly decreasing patterns, I.e. The vertical distribution of aerosols in calm weather or on pollution day belongs to the gradually decreasing pattern, while one on clean day or weak cold air day belongs to the rapidly decreasing pattern. The vertical distributive characters of aerosols were closely related with the dynamical/thermal structure and turbulence character of the atmosphere boundary layer. On the clean day, the low layer PM2.5 and PM10 concentrations were close to those at 8 m height, while the concentrations rapidly decreased at the high layer, and their values were only one half of those at 8 m, especially, the concentration of PM2.5 dropped even more. On the clean day, there existed stronger turbulence below 150 m, aerosols were well mixed, but blocked by the more stronger inversion layer aloft, and meanwhile, at various heights, especially in the high layer, the horizontal wind speed was larger, resulting in the rapid decrease of aerosol concentration, I.e. Resulting in the obvious vertical difference of aerosol concentrations between the low and high layers. On the pollution day, the concentrations of PM2.5 and PM10 at the low, middle, and high layers dropped successively by, on average, about 10% for each layer in comparison with those at 8 m height. On pollution days, in company with the low wind speed, there existed two shallow inversion layers in the boundary layer, but aerosols might be, to some extent, mixed below the inversion layer, therefore, on the pollution day the concentrations of PM2.5 and PM10 dropped with height slowly; and the observational results also show that the concentrations at 320 m height were obviously high under SW and SE winds, but at other heights, the concentrations were not correlated with wind directions. The computational results of footprint analysis suggest that this was due to the fact that the 320 m height was impacted by the pollutants transfer of southerly flow from the southern peripheral heavier polluted areas, such as Baoding, and Shijiazhuang of Hebei Province, Tianjin, and Shandong Province, etc., while the low layer was only affected by Beijing's local pollution source. The computational results of power spectra and periods preliminarily reveal that under the condition of calm weather, the periods of PM10 concentration at various heights of the tower were on the order of minutes, while in cases of larger wind speed, the concentrations of PM2.5 and PM10 at 320 m height not only had the short periods of minute-order, but also the longer periods of hour order. Consistent with the conclusion previously drawn by Ding et al., that air pollutants at different heights and at different sites in Beijing had the character of "in-phase" variation, was also observed for the diurnal variation and mean diurnal variation of PM2.5 and PM10 at various heights of the tower in this experiment, again confirming the "in-phase" temporal/spatial distributive character of air pollutants in the urban canopy of Beijing. The gentle double-peak character of the mean diurnal variation of PM2.5 and PM10 was closely related with the evident/similar diurnal variation of turbulent momentum fluxes, sensible heat fluxes, and turbulent kinetic energy at various heights in the urban canopy. Besides, under the condition of calm weather, the concentration of PM2.5 and PM10 declined with height slowly, it was 90% of 8 m concentration at the low layer, a little lesser than 90% at the middle layer, and 80% at the high layer, respectively. Under the condition of weak cold air weather, the concentration remarkably dropped with height, it was 70% of 8 m concentration at the low layer, and 20%―30% at the middle and high layers, especially the concentration of PM2.5 was even lower.     

Cl,F, and SO2 in Central American volcanic gases

The Cl, F, SO₂ contents and Cl/F and Cl/SO₄ ratios in Central American volcanic gases are examined. 10³?10⁵ tons SO₂ per day are given off during eruptions and 10² when a prominent vapor cloud persists between eruptive periods. Data regarding Cl and F and SO₄ from leachates, condensates, and incrustations are compared. Our data suggest circumpacific volcanoes are SO₂ poor relative to Cl and may be F poor although F is higher in basaltic Central American volcanoes than others.     

Estimating sediment accumulation rates in Manila Bay, a marine pollution hot spot in the Seas of East Asia

The GEF/UNDP/IMO/PEMSEA project identifies Manila Bay as among the marine pollution hot spots in the Seas of East Asia. ²¹⁰Pb dating of its sediment can provide a historical perspective of its pollution loading. However, the validity of ²¹⁰Pb dating in a complex dynamic coastal system of Manila Bay may come into question. Land-based sediment input can be high and physical and biological processes can possibly disturb the sediment layers. In this report, the ²¹⁰Pb profiles of sediment cores from different parts of the bay are presented. The linear sedimentation rates are shown to be higher in the recent past and are also variable across the bay. The largest change in sedimentation rate, coincided with the occurrence of a volcanic eruption in 1991 and is shown by applying a variant of the CIC model in sedimentation rate calculations. The data suggest that ²¹⁰Pb dating can be useful in estimating relative magnitudes of sedimentation rates, even in a complex dynamic coastal system like Manila Bay.