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81.
Turalioğlu FS 《Environmental monitoring and assessment》2005,104(1-3):119-130
Sulphur dioxide and PM10 levels are investigated in Erzurum during the periods of 1990–2000 heating season to assess air pollution level. For that reason, emissions of sulphur dioxide and particulate matter were calculated by using consumption of fuels and Turkish emission factors. These emission values were evaluated together with air pollution levels, which were measured at six stations in Erzurum atmosphere during 1990–2000 winter periods. Results reveal that in 1990–1994 heating period, there is an increasing trend in the emissions and air pollution levels over Erzurum, and the air quality limits were not met. The daily 24 h limit (short-term limit) was exceeded 127 days in 1992–1993 winter period. The reason for this increase was found to be the switching to use of low-quality fossil fuels instead of cleaner ones. Results also indicated that there was a considerable decrease in emissions of air pollutants and air pollution levels after 1995. This can be explained by the consumption of more high-quality fossil fuels. The correlation coefficient of SO2 with PM10 is obtained as r2 = 0.85, which is a high value supporting the idea that both pollutants are emitted from the same source. 相似文献
82.
Geostatistical Uncertainty Modelling for the Environmental Hazard Assessment During Single Erosive Rainstorm Events 总被引:1,自引:0,他引:1
Diodato N 《Environmental monitoring and assessment》2005,105(1-3):25-42
This paper presents an environmental hazard assessment to account the impacts of single rainstorm variability on river-torrential landscape identified as potentially vulnerable mainly to erosional soil degradation processes. An algorithm for the characterisation of this impact, called Erosive Hazard Index (EHI), is developed with a less expensive methodology. In EHI modelling, we assume that the river-torrential system has adapted to the natural hydrological regime, and a sudden fluctuation in this regime, especially those exceeding thresholds for an acceptable range of flexibility, may have disastrous consequences for the mountain environment. The hazard analysis links key rainstorm energy variables expressed as a single-storm erosion index (EIsto), with impact thresholds identified using an intensity pattern model. Afterwards, the conditional probabilities of exceeding these thresholds are spatially assessed using non-parametric geostatistical techinques, known as indicator kriging. The approach was applied to a test site in river-torrential landscape of the Southern Italy (Benevento province) for 13 November 1997 rainstorm event. 相似文献
83.
IMPACTS OF VISITORS ON SOIL AND VEGETATION OF THE RECREATIONAL AREA “NACIMIENTO DEL RÍO MUNDO” (CASTILLA-LA MANCHA, SPAIN) 总被引:1,自引:0,他引:1
Andrés-Abellán M Del Alamo JB Landete-Castillejos T López-Serrano FR García-Morote FA Del Cerro-Barja A 《Environmental monitoring and assessment》2005,101(1-3):55-67
This study examines the effects of recreational use on the soil and vegetation at a site of ecological importance (Nacimiento del Río Mundo, Albacete, Spain). The most visited sites showed increased soil compaction of approximately 50%, bare ground increase to 61 ± 10% and a decrease in richness (from 25 ± 2 to 15 ± 2 species), diversity (from 4.0 ± 0.1 to 2.7 ± 0.4) and stratification of plant species (from 80 ± 11 to 21 ± 4%). The most visited sites had 90% less plant species as compared to the least visited. Intense use was associated with the presence of nitrophilous plant and vegetal species with a morphology adapted to heavy trampling. The recreational areas showed a distribution pattern of impact radiating outwards from the most used and degraded point. At the most visited point, Los Chorros (the spring of the river), the impact radiated outwards for about 20 m. A pilot experiment examining the effects of one-year restriction to visitors for access to a formerly impacted area showed a plant cover increase by anthropic and not by native species of 57 percent units. 相似文献
84.
Krzysztof Brzozowski 《Environmental Modeling and Assessment》2006,11(4):371-380
The paper presents a new method of air pollution modelling on a micro scale. For estimation of concentration of car exhaust pollutants, each car is treated as an instantaneous moving emission source. This approach enables us to model time and spatial changes of emission, especially during cold and cool start of an engine. These stages of engine work are a source of significant pollution concentration in urban areas. In this work, two models are proposed: one for the estimation of emission after cold start of the engine and another for the prediction of pollutant concentration. The first model (defined for individual exhaust gas pollutants) enables us to calculate the emission as a function of time after the cold or cool start, ambient temperature and average speed of motion. This model uses the HBEFA database. The second mathematical model is developed in order to calculate the pollutant dispersion and concentrations. The finite volume method is applied to discretise the set of partial differential equations describing wind flow and pollutant dispersion in the domain considered. Models presented in this paper can be called short-term models on a small spatial scale. The results of numerical simulation of pollutant emission and dispersion are also presented. 相似文献
85.
中国土壤中溴,碘的背景含量 总被引:1,自引:0,他引:1
通过对全国八百余个表层土样的分析测试,获得了中国土壤中溴、碘背景含量的总体水平及在各土类中的含量,相对于地壳丰度,中国土壤中溴、碘普遍得到了富集,溴、碘含量分异变化较大,并具有明显的地域分异特征,影响中国土壤中溴、碘含量的主要因素是降水量、土壤吸附体的含量以及某些特殊母质。 相似文献
86.
本文系笔者对贵阳地区主要地质环境和工程地质特点进行的初步总结,内容为贵阳地区主要岩土构成情况、分布范围及与之相应的岩土工程地质特点和主要的岩土工程地质问题的描述,旨在给同行提供宏观性的了解和方向性的参考。 相似文献
87.
大气CO2浓度升高对农田生态系统的影响 总被引:1,自引:0,他引:1
自由大气CO2浓度升高(简称FACE,即Free A ir CO2Enrichment)对陆地生态系统的影响是全球变化研究中的一个热点。综述了FACE条件下,农田土壤植物生物量质量变化和土壤微生物对植物的反馈作用,以及土壤痕量气体排放的趋势变化。 相似文献
88.
地下车库汽车尾气污染源强计算浅析 总被引:2,自引:0,他引:2
近年来,地下车库空气污染越来越严重。在建设项目环境影响评价文件中.因为所采用的源强计算公式不同而导致不同的评价结果;所以就三种源强计算经验公式进行对比分析.发现公式二更适合地下车库污染源强的计算。 相似文献
89.
Quantity of trace arsenic in grain and soil was determined by hydride nondispersive atomic fluorescence method.Optimum conditions of measurement were selected in the experiment including the pH of the medium, reductive agent, the concentration and flowing velocity of KBH4, rate of carrier gas and atomized temperature. The reference sample of rice C was determined and the linear relationship of the calibration curve was plotted, indicating that the method was highly precise. In the experiment of recovery rate, the method was quite satisfactory.Based on the determination of hundreds of samples, it is proved that atomic fluorescence method is rapid, sensitive and low in interference. It is very efficient on determination of trace arsenic in soils and grains, especially in grains. 相似文献
90.