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101.
气象因子对臭氧的影响及其在空气质量预报中的应用 总被引:1,自引:0,他引:1
为提高重庆市臭氧(O_3)预报准确率,利用2013—2015年5—10月O_3监测数据和气象数据,通过主成分分析、逐步回归分析等方法,确定了影响重庆O_3浓度的主要气象因素为最高温度、温差、太阳辐射、降水量、相对湿度、水气压和压差;通过基于O_3污染水平相似的主要气象控制因子筛选和最优组合的预报结果优化方法,提高了O_3预报准确率,使2016年5—8月O_3的AQI类别预报准确率由57.7%增至72.4%,O_3超标的预报准确率由38%增至46%。 相似文献
102.
贵州省部分地区土壤中酞酸酯类污染现状调查 总被引:5,自引:1,他引:4
对贵州省部分地区表层土壤中酞酸酯类的污染状况进行了调查。分别在遵义地区、黔南地区、黔东南地区和毕节地区采集483个土壤样品分析,结果表明,样品中酞酸酯总质量比(ΣPAEs)为未检出~8.22 mg/kg,均值为0.63 mg/kg。其中DEHP和DBP为主要污染物,均值分别为0.32 mg/kg和0.24 mg/kg,检出率分别为90.89%和97.10%。 相似文献
103.
Mecozzi M Pietroletti M Scarpiniti M Acquistucci R Conti ME 《Environmental monitoring and assessment》2012,184(10):6025-6036
The aim of this study is to present and to discuss some characteristics of recalcitrant organic matter mechanism and formation. These aggregates called mucilages that are produced by the degradation reactions of several algae, have been investigated by infrared (FTIR) spectroscopy. FTIR spectra of macroaggregates produced by different algal samples have been daily collected in order to investigate the steps of aggregation. Afterwards, they have been elaborated by means of Independent Component Analysis (ICA). ICA investigation of FTIR spectra showed that the global aggregation process of marine mucilage always consisted of two different phases or independent components (ICs). One IC is related to the first degradation step of algal cells leading to the production of mono and oligosaccharides with aminoacids and oligopeptides. The second IC is related to the polymerization of oligosaccharides with aminoacids and oligopeptides and to their interaction with less polar compounds such as lipids thus producing supramolecular structures. The emerging mechanisms of anomalous size aggregates of organic matter match those of natural organic matter aggregation. The approach we suggest is to use synthetic mucilages which allows to monitor the macroaggregates formation because it can hardly be performed by means of natural marine macroaggregates. 相似文献
104.
Manuela C Francesco T Tiziana C Assunta C Lara S Nadia N Giorgia A Barbara S Maria F Carlotta C Valeria DG Pia SM Gianfranco T Angela S 《Journal of environmental monitoring : JEM》2012,14(6):1542-1550
To evaluate exposure to benzene in urban and rural areas, an investigation into personal exposure to benzene in traffic policemen, police drivers and rural (roadmen) male outdoor workers was carried out. Personal samples and data acquired using fixed monitoring stations located in different areas of the city were used to measure personal exposure to benzene in 62 non-smoker traffic policemen, 22 police drivers and 57 roadmen. Blood benzene, urinary trans-trans muconic acid (t,t-MA) and S-phenyl-mercapturic acid (S-PMA) were measured at the end of work shift in 62 non-smoker traffic policemen, 22 police drivers and 57 roadmen and 34 smoker traffic policemen, 21 police drivers and 53 roadmen. Exposure to benzene was similar among non-smoker traffic policemen and police drivers and higher among non-smoker urban workers compared to rural workers. Blood benzene, t,t-MA and S-PMA were similar among non-smoker traffic policemen and police drivers; blood benzene and t,t-MA were significantly higher in non-smoker urban workers compared to rural workers. Significant increases in t,t-MA were found in smokers vs. non-smokers. In non-smoker urban workers airborne benzene and blood benzene, and t,t-MA and S-PMA were significantly correlated. This study gives an evaluation of the exposure to benzene in an urban area, comparing people working in the street or in cars, to people working in a rural area. Benzene is a certain carcinogen for humans. The results we showed should lead to more in-depth studies about the effects on health of these categories of workers. 相似文献
105.
A simple linear model for estimating ozone AOT40 at forest sites from raw passive sampling data 总被引:1,自引:0,他引:1
M Ferretti F Cristofolini A Cristofori G Gerosa E Gottardini 《Journal of environmental monitoring : JEM》2012,14(8):2238-2244
A rapid, empirical method is described for estimating weekly AOT40 from ozone concentrations measured with passive samplers at forest sites. The method is based on linear regression and was developed after three years of measurements in Trentino (northern Italy). It was tested against an independent set of data from passive sampler sites across Italy. It provides good weekly estimates compared with those measured by conventional monitors (0.85 ≤R(2)≤ 0.970; 97 ≤ RMSE ≤ 302). Estimates obtained using passive sampling at forest sites are comparable to those obtained by another estimation method based on modelling hourly concentrations (R(2) = 0.94; 131 ≤ RMSE ≤ 351). Regression coefficients of passive sampling are similar to those obtained with conventional monitors at forest sites. Testing against an independent dataset generated by passive sampling provided similar results (0.86 ≤R(2)≤ 0.99; 65 ≤ RMSE ≤ 478). Errors tend to accumulate when weekly AOT40 estimates are summed to obtain the total AOT40 over the May-July period, and the median deviation between the two estimation methods based on passive sampling is 11%. The method proposed does not require any assumptions, complex calculation or modelling technique, and can be useful when other estimation methods are not feasible, either in principle or in practice. However, the method is not useful when estimates of hourly concentrations are of interest. 相似文献
106.
Maria Virgínia Alves Martins Fabrizio Frontalini Lazaro L. M. Laut Frederico S. Silva João Moreno Silvia Sousa Noureddine Zaaboub Monia El Bour Fernando Rocha 《Environmental monitoring and assessment》2014,186(12):8875-8897
Ria de Aveiro, which is located in the centre of Portugal (40° 38′ N, 8° 45′ W), is a well-mixed and complex coastal lagoon that is separated from the sea by a sandy barrier and connects with the Atlantic through an artificial inlet. Tidal currents are the main factor controlling the lagoon’s hydrodynamics and, to a great extent, the sedimentary dynamic. The inner lagoonal zones receive input from several rivers and experience the pressure caused by the accumulation of organic matter and pollutants (namely, trace metals) from diverse anthropic activities. This paper is the first piece of work aiming to recognize, characterize and explain the main benthic foraminiferal biotopes in Ria de Aveiro. To provide a broad overview of this kind of setting, our results are compared to those of previous published studies conducted in similar transitional environments. The research is based on an investigation of 225 sites spread throughout this ecosystem. Utilizing a statistical approach, this study analyses the details of dead benthic foraminiferal assemblages composed of 260 taxa, the texture and composition (mineralogical and geochemical) of the sediment and physicochemical data. On the basis of the results of R-mode and Q-mode cluster analyses, several different biotopes can be defined as marsh biotope/near-marsh biotope; marginal urban/marginal urban mixing biotope; inner-outer lagoon biotope or enclosed lagoon; outer lagoon biotope, mixed sub-biotope; and outer lagoon, marine sub-biotope. These biotopes are related to foraminifera assemblages and substrate type and are influenced by local currents, water depth, chemical and physicochemical conditions, river or oceanic proximity, and anthropogenic impact, as evidenced by the mapping of the six factor loadings of the principal component analysis conducted herein. Based on a similar methodology of analysis as that applied in previous studies in the Lagoon of Venice, comparable biotypes were identified in Lagoon of Aveiro. 相似文献
107.
Rivera D Granda S Arumí JL Sandoval M Billib M 《Environmental monitoring and assessment》2012,184(11):6563-6574
Soil moisture is the key link among hydroecological compartments, responding dynamically to sequences of atmospheric processes and management conditions and modulating physical, chemical, and biological processes in the soil. Currently, there are a variety of monitoring techniques to measure, directly or indirectly, the soil moisture. However, some practical issues remain open like the definition a priori of the number, location and depth of the monitoring points, and the impact of failing or poor performance soil moisture sensors. Here, we present a set of techniques, namely Δθ time series, wavelet filtering, and time stability, to identify representative points and monitoring depths through an analysis of hourly soil moisture time series for different configuration of the monitoring network. We used real data from a monitoring network consisting of seven monitoring points, each one with four EC-5 probes (Decagon Devices Inc., Pullman, WA) at 20, 40, 60, and 100?cm. The use of simple time series of Δθ allowed us to assess the spatiotemporal influence of the monitoring points, while the wavelet periodograms allowed us to get insight about the response of the monitoring points at different time scales. Both methods are easy to implement or adapt to specific conditions, being coherent to the results derived from time stability analysis. For our case study, we concluded that we could reallocate 16 sensors (out of 28) without a significant loss of information. However, the final decision strongly relies on a deep knowledge of the site features and the objectives of the monitoring network. 相似文献
108.
Jürgens N Schmiedel U Haarmeyer DH Dengler J Finckh M Goetze D Gröngröft A Hahn K Koulibaly A Luther-Mosebach J Muche G Oldeland J Petersen A Porembski S Rutherford MC Schmidt M Sinsin B Strohbach BJ Thiombiano A Wittig R Zizka G 《Environmental monitoring and assessment》2012,184(2):655-678
The international, interdisciplinary biodiversity research project BIOTA AFRICA initiated a standardized biodiversity monitoring network along climatic gradients across the African continent. Due to an identified lack of adequate monitoring designs, BIOTA AFRICA developed and implemented the standardized BIOTA Biodiversity Observatories, that meet the following criteria (a) enable long-term monitoring of biodiversity, potential driving factors, and relevant indicators with adequate spatial and temporal resolution, (b) facilitate comparability of data generated within different ecosystems, (c) allow integration of many disciplines, (d) allow spatial up-scaling, and (e) be applicable within a network approach. A BIOTA Observatory encompasses an area of 1?km2 and is subdivided into 100 1-ha plots. For meeting the needs of sampling of different organism groups, the hectare plot is again subdivided into standardized subplots, whose sizes follow a geometric series. To allow for different sampling intensities but at the same time to characterize the whole square kilometer, the number of hectare plots to be sampled depends on the requirements of the respective discipline. A hierarchical ranking of the hectare plots ensures that all disciplines monitor as many hectare plots jointly as possible. The BIOTA Observatory design assures repeated, multidisciplinary standardized inventories of biodiversity and its environmental drivers, including options for spatial up- and downscaling and different sampling intensities. BIOTA Observatories have been installed along climatic and landscape gradients in Morocco, West Africa, and southern Africa. In regions with varying land use, several BIOTA Observatories are situated close to each other to analyze management effects. 相似文献
109.
Giuseppa Di Bella Vincenzo Lo Turco Angela Giorgia Potortì Rossana Rando Patrizia Licata Giacomo Dugo 《Environmental monitoring and assessment》2013,185(9):7517-7525
Our study was carried out on two species of clams, Venerupis aurea laeta and Cerastoderma edule glaucum, from Ganzirri Lake considered as “environmental biomarkers” for their changes in physiology, morphology or distribution under the influence of substances in the environment. The aim of the present study was to conduct a statistical analysis on Venerupis and Cerastoderma to investigate the difference between the two autochthonous clams according to the presence of metals, and to link metal concentrations to the reproductive cycle of clam during 2009–2010. Metal analysis was carried out with inductively coupled plasma mass spectrometry (ICP-MS). Accuracy and precision were assessed by analyzing the certified standard matrix: mussel tissue NIST SRM 2976. The multivariate analysis was made using the SPSS 13.0 software package for Windows (SPSS Inc., Chicago, IL). In this study, the concentrations of some metals found in clam tissues showed seasonal cycles with higher values in summer than in winter. The significances of metal concentrations differences between Venerupis and Cerastoderma samples were estimated with Mann–Whitney U-test. The concentrations of Ag, As, Cd, Mn, Se and Zn show a significant p-level that suggests a difference between the two group samples. Statistical analysis showed that the link of metal concentrations to the reproductive cycles of Venerupis and Cerastoderma was not evident. 相似文献
110.
采用隔声窗作为典型道路的交通噪声控制措施,探索隔声性能的现场监测方法。分别选取真空玻璃窗与中空玻璃窗进行监测,两种隔声窗对交通噪声1000 Hz 和2000 Hz 两个倍频带的隔声量最大,真空玻璃隔声窗对500 Hz 倍频带及以下的噪声比中空玻璃隔声窗更有效,如果采用两种隔声窗进行组合,在全频带的隔声量达到25 dB。 相似文献