Estimating shipping emissions in the region of the Sea of Marmara, Turkey

Ship emissions are significantly increasing globally and have remarkable impact on air quality on sea and land. These emissions contribute serious adverse health and environmental effects. Territorial waters, inland seas and ports are the regions most affected by ship emissions. As an inland sea the Sea of Marmara is an area that has too much ship traffic. Since the region of the Marmara is highly urbanized, emissions from ships affect human health and the overall environment. In this paper exhaust gas emissions from ships in the Sea of Marmara and the Turkish Straits are calculated by utilizing the data acquired in 2003. Main engine types, fuel types, operations types, navigation times and speeds of vessels are taken into consideration in the study. Total emissions from ships in the study area were estimated as 5,451,224 t y(-1) for CO(2), 111,039 t y(-1) for NO(x), 87,168 t y(-1) for SO(2), 20,281 t y(-1) for CO, 5801 t y(-1) for VOC, 4762 t y(-1) for PM. The shipping emissions in the region are equivalent to 11% of NO(x) 0.1% of CO and 0.12% of PM of the corresponding total emissions in Turkey. The shipping emissions in the area are 46% of NO(x), 25% of PM and 1.5% of CO of road traffic emissions in Turkey data between which and correspond to a higher level than aircraft emissions and rail emissions in Turkey.     

Spatialised fate factors for nitrate in catchments: modelling approach and implication for LCA results

The challenge for environmental assessment tools, such as Life Cycle Assessment (LCA) is to provide a holistic picture of the environmental impacts of a given system, while being relevant both at a global scale, i.e., for global impact categories such as climate change, and at a smaller scale, i.e., for regional impact categories such as aquatic eutrophication. To this end, the environmental mechanisms between emission and impact should be taken into account. For eutrophication in particular, which is one of the main impacts of farming systems, the fate factor of eutrophying pollutants in catchments, and particularly of nitrate, reflects one of these important and complex environmental mechanisms. We define this fate factor as: the ratio of the amount of nitrate at the outlet of the catchment over the nitrate emitted from the catchment's soils. In LCA, this fate factor is most often assumed equal to 1, while the observed fate factor is generally less than 1. A generic approach for estimating the range of variation of nitrate fate factors in a region of intensive agriculture was proposed. This approach was based on the analysis of different catchment scenarios combining different catchment types and different effective rainfalls. The evolution over time of the nitrate fate factor as well as the steady state fate factor for each catchment scenario was obtained using the INCA simulation model. In line with the general LCA model, the implications of the steady state fate factors for nitrate were investigated for the eutrophication impact result in the framework of an LCA of pig production. A sensitivity analysis to the fraction of nitrate lost as N(2)O was presented for the climate change impact category. This study highlighted the difference between the observed fate factor at a given time, which aggregates both storage and transformation processes and a "steady state fate factor", specific to the system considered. The range of steady state fate factors obtained for the study region was wide, from 0.44 to 0.86, depending primarily on the catchment type and secondarily on the effective rainfall. The sensitivity of the LCA of pig production to the fate factors was significant concerning eutrophication, but potentially much larger concerning climate change. The potential for producing improved eutrophication results by using spatially differentiated fate factors was demonstrated. Additionally, the urgent need for quantitative studies on the N(2)O/N(2) ratio in riparian zones denitrification was highlighted.     

Normalisation in product life cycle assessment: an LCA of the global and European economic systems in the year 2000

In the methodological context of the interpretation of environmental life cycle assessment (LCA) results, a normalisation study was performed. 15 impact categories were accounted for, including climate change, acidification, eutrophication, human toxicity, ecotoxicity, depletion of fossil energy resources, and land use. The year 2000 was chosen as a reference year, and information was gathered on two spatial levels: the global and the European level. From the 860 environmental interventions collected, 48 interventions turned out to account for at least 75% of the impact scores of all impact categories. All non-toxicity related, emission dependent impacts are fully dominated by the bulk emissions of only 10 substances or substance groups: CO(2), CH(4), SO(2), NO(x), NH(3), PM(10), NMVOC, and (H)CFCs emissions to air and emissions of N- and P-compounds to fresh water. For the toxicity-related emissions (pesticides, organics, metal compounds and some specific inorganics), the availability of information was still very limited, leading to large uncertainty in the corresponding normalisation factors. Apart from their usefulness as a reference for LCA studies, the results of this study stress the importance of efficient measures to combat bulk emissions and to promote the registration of potentially toxic emissions on a more comprehensive scale.     

The environmental impact of mastitis: a case study of dairy herds

Mastitis is defined as an inflammatory reaction of udder tissue to bacterial, chemical, thermal or mechanical injury, which causes heavy financial losses and milk wastage throughout the world. Until now, studies have focused on the economic aspects from which perspective mastitis can generally be considered as the most serious disease in dairy cows; however, costs are not the only negative consequence resulting from the infection. The environmental impact is also significant; milk is discarded, which means lower efficiency and hence a greater environmental impact per produced liter of milk. Less milk is produced, which leads to an increased need for calf feed, and meat production is also affected. The main aim of this paper was to quantify the environmental impact of mastitis incidence. A standard scenario (representative of present-day reality in Galicia, Spain) and an improved scenario (in which mastitis incidence rate is reduced by diverse actions) have been defined and compared using Life Cycle Assessment (LCA) methodology. Among the impact categories studied, acidification, eutrophication and global warming were found to be the most significant environmental impacts. In all these categories, it was revealed that a decrease in mastitis incidence has a positive influence as the environmental impact is reduced. Even if the quantitative results cannot show a considerable decrease in the environmental burden, the impact cannot be regarded as negligible when the total consumption or total production of a region is considered. For example, the outcome of the proposed improvement measures for Spain's greenhouse gas emissions can be quantified as 0.06% of total emissions and 0.56% of emissions by the agricultural sector.     

Multiple effects and uncertainties of emission control policies in China: Implications for public health, soil acidification, and global temperature

Policies to control emissions of criteria pollutants in China may have conflicting impacts on public health, soil acidification, and climate. Two scenarios for 2020, a base case without anticipated control measures and a more realistic case including such controls, are evaluated to quantify the effects of the policies on emissions and resulting environmental outcomes. Large benefits to public health can be expected from the controls, attributed mainly to reduced emissions of primary PM and gaseous PM precursors, and thus lower ambient concentrations of PM_2.5. Approximately 4% of all-cause mortality in the country can be avoided (95% confidence interval: 1-7%), particularly in eastern and north-central China, regions with large population densities and high levels of PM_2.5. Surface ozone levels, however, are estimated to increase in parts of those regions, despite NO_X reductions. This implies VOC-limited conditions. Even with significant reduction of SO₂ and NO_X emissions, the controls will not significantly mitigate risks of soil acidification, judged by the exceedance levels of critical load (CL). This is due to the decrease in primary PM emissions, with the consequent reduction in deposition of alkaline base cations. Compared to 2005, even larger CL exceedances are found for both scenarios in 2020, implying that PM control may negate any recovery from soil acidification due to SO₂ reductions. Noting large uncertainties, current polices to control emissions of criteria pollutants in China will not reduce climate warming, since controlling SO₂ emissions also reduces reflective secondary aerosols. Black carbon emission is an important source of uncertainty concerning the effects of Chinese control policies on global temperature change. Given these conflicts, greater consideration should be paid to reconciling varied environmental objectives, and emission control strategies should target not only criteria pollutants but also species such as VOCs and CO₂.     

Evaluating river water quality through land use analysis and N budget approaches in livestock farming areas

This study was carried out to evaluate the quality of river water by analysis of land use in drainage basins and by estimating the N budgets. The drainage basins of Shibetsu River (Shibetsu area) and Bekkanbeushi River (Akkeshi area) in eastern Hokkaido, Japan were selected for a case study, and the evaluation of water quality was up-scaled to the regional level in Hokkaido by using the Arcview/GIS and statistical information. Water sampling was carried out in August 2001 and May 2002 in the Shibetsu and Akkeshi areas, respectively. The proportions of major land uses in drainage basins such as upland field, forest, urban area, wetland and wasteland for each sampling site were estimated by using topographic maps scaled at 1:25,000. The linear regression results showed that the correlation between NO3-N concentration and the proportion of upland in the drainage basins was highly and positively significant for both the Shibetsu area (r = 0.84, n = 57) and the Akkeshi area (r = 0.71, n = 73) at < 0.001 significance level. The regression coefficients or impact factors of river water quality were 0.015 and 0.0052 for the Shibetsu and Akkeshi areas, respectively. A comparison of these results with that of the previous study results in Hokkaido indicated that the impact factors were highest for intensive livestock farming areas (0.040), medium for mixed agriculture and livestock farming (0.020-0.030), and the lowest for grassland-based dairy cattle and horse farming areas (0.0052-0.015). The results of a simple regression analysis showed that the impact factors had a significant positive correlation with the cropland surplus N (r = 0.93, P < 0.01), chemical fertilizer N (r = 0.82, P < 0.05), and manure fertilizer N (r = 0.76, P < 0.05), which were estimated by using the N budget approach. Using the best-correlated regression model, impact factors for all cities, towns and villages of the Hokkaido region were estimated. The NO3-N concentrations for all major rivers in Hokkaido were predicted by multiplying the estimated impact factors by the proportion of uplands. The regression analysis indicated that the predicted NO3-N concentrations were significantly correlated (r = 0.62, P < 0.001, n = 203) with the measured NO3-N concentrations, reported previously. It can be concluded that estimating the proportions of upland fields in drainage basins, and calculating cropland surplus N enables us to predict river water quality with respect to NO3-N concentration.     

Measurements of N2O and CH4 from the aerated composting of food waste

Emissions of N2O and CH4 from an aerated composting system were investigated using small-scale simulated reactors. The results show relatively high emissions of N2O at the beginning of composting, in proportion to the application amount of food waste. After 2 days, the N2O emission decreased to 0.53 ppmv on average, near to the background level in the atmosphere (0.45 ppmv). The addition of composted cattle manure increased N2O emissions not only at the beginning of composting, but also during the later period and resulted in two peak emission curves. Good correlation was observed between the N2O concentration at the air outlet and NO2- concentration in waste, suggesting a generation pathway for N2O from NO2- to N2O. Methane was only detected in treatments containing composted cattle manure. The high emission of methane illustrates the involvement of anoxic/anaerobic microorganisms with the addition of composted manure. The result suggests the existence of anoxic or anaerobic microsite inside the waste particles even though ventilation was employed during the composting process.     

Experimental investigation on the performance, gaseous and particulate emissions of a methanol fumigated diesel engine

Experiments were conducted on a 4-cylinder direct-injection diesel engine with fumigation methanol injected into the air intake of each cylinder. The fumigation methanol was injected to top up 10%, 20% and 30% of the power output under different engine operating conditions. The effects of fumigation methanol on engine performance, gaseous emissions and particulate emission were investigated. The experimental results show that there is a decrease in the brake thermal efficiency when fumigation methanol is applied, except at the highest load of 0.67 MPa. At low loads, the brake thermal efficiency decreases with increase in fumigation methanol; but at high loads, it increases with increase in fumigation methanol. The fumigation method results in a significant increase in hydrocarbon (HC), carbon monoxide (CO), and nitrogen dioxide (NO(2)) emissions. The concentration of nitrogen oxides (NOx) is significantly reduced except at close to full load condition. There is also a reduction in the smoke opacity and the particulate matter (PM) mass concentration. For the submicron particles, the total number of particles decreases at low and medium loads but increases at high loads. In all cases, there is a shift of the particles towards smaller geometrical mean diameter, especially at high loads. The increase in nano-sized particles and the increase in NO(2) emission could have serious impact on human health.     

Estimating national exhaust emissions from railway vehicles in Turkey

The estimated exhaust emissions from railway vehicles in Turkey were presented. The emissions of nitrogen oxides (NO(X)), hydrocarbon compounds (HC), carbon monoxide (CO), particulate matter (PM), sulfur dioxide (SO(2)) and carbon dioxide (CO(2)) from the diesel locomotives and railcars were calculated using the railway traffic data recorded by Turkish State Railways (TSR) for the period of 2000-2005. EPA emission factors were used for different vehicle types and operation modes such as shunting and line-hauling. Total emissions from railway vehicles in Turkey were estimated as 384 t y(-1) for HC, 1016 t y(-1) for CO, 6799 t y(-1) for NO(X), 256 t y(-1) for PM, 357 t y(-1) for SO(2) and 383 537 t y(-1) for CO(2) for the year 2005. The distribution of emissions with respect to type of railway vehicles shows that the mainline locomotives contribute approximately 91% to the total emissions. The increases of 22%, 39% and 49% in the current numbers of mainline locomotives, shunting locomotives and diesel railcars, respectively corresponding to the full capacity of railway network in Turkey will increase the annual emissions to 431 t y(-1) for HC, 1121 t y(-1) for CO, 7399 t y(-1) for NO(X), 342 t y(-1) for PM, 552 t y(-1) for SO(2) and 420 256 t y(-1) for CO(2). Total railway emissions constitute 0.15%, 0.08% and 4.21% of total Turkish traffic emissions for HC, CO and NO(X), respectively.     

The potential for a suite of isotope and chemical markers to differentiate sources of nitrate contamination: a review

Nitrate is naturally found within the environment as part of the nitrogen cycle. However, anthropogenic inputs have greatly increased nitrate loads within ground and surface waters. This has had a severe impact on aquatic ecosystems and has given rise to health considerations in humans and livestock. Therefore, the identification of nitrate sources is important in preserving water quality and achieving sustainability of our water resources. Nitrate sources can be determined based on the nitrate nitrogen (N) and oxygen (O) isotopic compositions (δ¹⁵N, δ¹⁸O). However, sewage and manure have overlapping δ¹⁵N and δ¹⁸O values making their differentiation on this basis problematic. The specific differentiation between sources of faecal contamination is of particular importance, because the risk to humans is usually considered higher from human faecal contamination (sewage) than from animal faecal contamination. This review summarises the current state of knowledge in using isotope tracers to differentiate various nitrate sources and identifies potential chemical tracers for differentiating sewage and manure. In particular, an in depth review of the current state of knowledge regarding the necessary considerations in using chemical markers, such as pharmaceuticals and food additives, to differentiate sewage and manure sources of nitrate contamination will be given, through an understanding of their use, occurrence and fate, in order to identify the most suitable potential chemical markers.     

Assessment of pre-service teachers’ knowledge of the impact of livestock production on global warming: a comparative study between Portugal and Spain

In this study we assess how higher education students (pre-service teachers) value and understand the impact of livestock production on global warming. We used a questionnaire with 91 students from a Portuguese institution and 111 from a Spanish one. The students had to mention measures to fight global warming, to explain the relationship between livestock production and global warming and to rank the impact of this cause compared to others. The Portuguese students showed a better understanding of this issue. Even so, the majority of the students do not recognize the high impact of livestock on global warming and consider other causes more relevant.     

Penetration of nitrogen oxides and particles from outdoor into indoor air and removal of the pollutants through filtration of incoming air

We studied the effect of ventilation and air filtration systems on indoor air quality in a children's day-care center in Finland. Ambient air nitrogen oxides (NO, NO2) and particles (TSP, PM10) were simultaneously measured outdoors and indoors with automatic nitrogen oxide analyzers and dust monitoring. Without filtration nitrogen oxides and particulate matter generated by nearby motor traffic penetrated readily indoors. With chemical filtration 50-70% of nitrogen oxides could be removed. Mechanical ventilation and filtration also reduced indoor particle levels. During holidays and weekends when there was no opening of doors and windows and no particle-generating activity indoors, the indoor particle level was reduced to less than 10% of the outdoor level. At times when outdoor particle concentrations were high during weekdays, the indoor level was about 25% of the outdoor level. Thus, the possible adverse health effects of nitrogen oxides and particles indoors could be countered by efficient filtration. We also showed that inclusion of heat recovery equipment can make new ventilation installations economical.     

2002 summer fires in Lithuania: impact on the Vilnius city air quality and the inhabitants health

The episodes with highly elevated concentrations of particulate matter (PM10), NOx, and CO were detected in the city of Vilnius between August and September 2002 and possible reasons were analysed. This increase was attributed to emissions from fires in the vicinity of the city of Vilnius when data on fire location and start, wind direction and concentrations of pollutants were analysed. The correlation coefficient between PM10 and CO, NO, NO2, NOx increased during the fire period in comparison with the same correlation after the fire period. During the fire episodes, there was an increase in concentration of ozone precursors, and meteorological conditions were favourable for photochemical reactions. Therefore, the hourly values for ozone exceeded the values common for Vilnius. Generally, during the episodes, the maximum of NO2 concentrations was 2 times higher than the limit value for NO2 laid down in the Council Directives 1999/30/EC [Council Directive 1999/30/EC of 22 April 1999 relating to limit values for sulphur dioxide, nitrogen dioxide and oxides of nitrogen, particulate matter and lead in ambient air. Official Journal L 163, 29/06/1999: 0041-0060], and that of PM10 was even 5.5 times higher than the limit value for PM10. Human health effects study in Vilnius indicated that the incidents of documented respiratory diseases and exacerbation of the bronchial asthma during the fire period were up to 20 times higher in comparison to periods with no fires.     

A modelling approach to global nitrate leaching caused by anthropogenic fertilisation

Water quality associated with nitrate (NO3-) leaching from agricultural soils is an important environmental issue. This paper describes a new modelling approach to quantitatively evaluate the effect of the use of fertilisers on global nitrate leaching. A global process-based simulation model was previously developed for the nitrogen cycle in terrestrial ecosystems, in which soil inorganic nitrogen in the form of ammonium (NH4+) and NO3- was considered. After introducing data on world fertiliser consumption (FAO, 1995) into the steady-state model, the extent of disturbance to the nitrogen cycle caused by fertilisation was calculated. Although fertilisation resulted in an annual increase in net primary production (NPP, represented as carbon) of 18 Gt year-1, NO3- leaching and gaseous losses of nitrogen oxides and ammonia were also accelerated. Most regions with heavy fertiliser application (over 100 kg ha-1 year-1) showed a high annual leaching load equal to or more than 20 kg ha-1 year-1. About 2.5% of the land area occupied by terrestrial ecosystems suffered a serious leaching load of more than 30 kg ha-1 year-1. Of the total amount of applied fertilisers (138 Tg year-1) 19% was lost to NO3- leaching, 8% to gaseous ammonia, and 3% to gaseous nitrogen oxides. The rest was assumed to be fixed in the ecosystems through vegetation uptake.     

Biogenic emissions of isoprenoids and NO in China and comparison to anthropogenic emissions

In this study, a regional dynamical model (WRF) is used to drive biogenic emission models to calculate high resolution (10x10 km) biogenic emissions of isoprene (C(5)H(8)), monoterpenes (C(10)H(16)), and nitric oxide (NO) in China. This high resolution biogenic inventory will be available for the community to study the effect of biogenic emissions on photochemical oxidants in China. The biogenic emissions are compared to anthropogenic emissions to gain insight on the potential impact of the biogenic emissions on tropospheric chemistry, especially ozone production in this region. The results show that the biogenic emissions in China exhibit strongly diurnal, seasonal, and spatial variations. The isoprenoid (including both isoprene and monoterpenes) emissions are closely correlated to tree density and strongly vary with season and local time. During winter (January), the biogenic isoprenoid emissions are the lowest, resulting from lower temperature and solar radiation, and highest in summer (July) due to higher temperature and solar radiation. The biogenic NO emissions are also higher during summer and lower during winter, but the magnitude of the seasonal variation is smaller than the emissions of isoprene and monoterpenes. The biogenic emissions of NO are widely spread out in the northern, eastern, and southern China regions, where high-density agricultural soil lands are located. Both biogenic NO and isoprenoid emissions are very small in western China. The calculated total biogenic emission budget is smaller than the total anthropogenic VOC emission budget in China. The biogenic isoprenoid and anthropogenic VOC emissions are 10.9 and 15.1 Tg year(-1), respectively. The total biogenic and anthropogenic emissions of NO are 5.9 and 11.5 Tg(NO) year(-1), respectively. The study shows that in central eastern China, the estimated biogenic emissions of isoprenoids are very small, and the anthropogenic emissions of VOCs are dominant in this region. However, in northeastern and southern China, there are relatively large biogenic emissions of isoprenoids, leading to an important impact on the ozone production in these regions. Furthermore, the emissions of isoprenoids are highest during summer and noontime, which correlates to the peak of ozone production period. For example, the ratio between summer and winter for the emissions of isoprenoids is about 15 in China. As a result, the biogenic emissions of isoprenoids are significantly larger than the anthropogenic emissions of VOCs in China during daytime in summer. Biogenic NO emissions are mostly produced by agricultural soils which co-exist with large populations and human activity. As a result, the biogenic emissions of NO are mostly overlapped with the anthropogenic emissions of NO, leading to the enhancement in NO concentrations in the high anthropogenic NO emission regions. Finally, the future emissions of isoprene and monoterpenes over China are estimated. The results show that the future biogenic emissions may increase significantly due to land cover changes in central eastern China, which could have a very important impact on ozone formation in this region. However, these estimates are highly uncertain and are presented as a potential scenario to show the importance of possible changes of biogenic emissions in China.     

Environmental assessment of anaerobically digested sludge reuse in agriculture: Potential impacts of emerging micropollutants

Agricultural application of sewage sludge has been emotionally discussed in the last decades, because the latter contains organic micropollutants with unknown fate and risk potential. In this work, the reuse of anaerobically digested sludge in agriculture is evaluated from an environmental point of view by using Life Cycle Assessment methodology. More specifically, the potential impacts of emerging micropollutants, such as pharmaceuticals and personal care products, present in the sludge have been quantified. Four scenarios were considered according to the temperature of the anaerobic digestion (mesophilic or thermophilic) and the sludge retention time (20 or 10 d), and they have been compared with the non-treated sludge.From an environmental point of view, the disposal of undigested sludge is not the most suitable alternative, except for global warming due to the dominance (65-85%) of the indirect emissions associated to the electricity use. Nutrient-related direct emissions dominate the eutrophication category impact in all the scenarios (>71.4%), although a beneficial impact related to the avoidance of industrial fertilisers production is also quantified (up to 6.7%). In terms of human and terrestrial toxicity, the direct emissions of heavy metals to soil dominate these two impact categories (>70%), and the contribution of other micropollutants is minimal. Moreover, only six (Galaxolide, Tonalide, Diazepam, Ibuprofen, Sulfamethoxazole and 17α-ethinyloestradiol) out of the 13 substances considered are really significant since they account for more than 95% of the overall micropollutants impact.     

Motorcycle emissions and fuel consumption in urban and rural driving conditions

This work reports sampling of motorcycle on-road driving cycles in actual urban and rural environments and the development of representative driving cycles using the principle of least total variance in individual regions. Based on the representative driving cycles in individual regions, emission factors for carbon monoxide (CO), hydrocarbons (HC), nitrogen oxides (NO(x)=NO+NO(2)) and carbon dioxide (CO(2)), as well as fuel consumption, were determined using a chassis dynamometer. The measurement results show that the representative driving cycles are almost identical in the three largest cities in Taiwan, but they differ significantly from the rural driving cycle. Irrespective of driving conditions, emission factors differ insignificantly between the urban and rural regions at a 95% confidence level. However, the fuel consumption in urban centers is approximately 30% higher than in the rural regions, with driving conditions in the former usually poor compared to the latter. Two-stroke motorcycles generally have considerably higher HC emissions and quite lower NO(x) emissions than those of four-stroke motorcycles. Comparisons with other studies suggest that factors such as road characteristics, traffic volume, vehicle type, driving conditions and driver behavior may affect motorcycle emission levels in real traffic situations.     

An environmental assessment of wood and steel reinforced concrete housing construction

Wooden type of housing is ubiquitous in Japan. It is the main structure for housing; however, due to the increase in residential developments, steel reinforced concrete houses are also on the rise. This paper assesses the environmental impacts of these two types of construction. An evaluation of the two types of construction in terms of energy usage and air emissions is done. A comparison of the damage costs due to the generated emissions is also considered. Four types of emissions generated are evaluated, namely carbon emissions (CO₂), nitrogen oxides (NO_x), sulfur oxides (SO_x) and suspended particulate matter (SPM). The life cycle of the two different housing construction types is traced and environmental impacts are determined. External costs are also calculated. Furthermore, different improvement assessment scenarios are simulated to ascertain several emission reduction possibilities. The study looks into the emitted emissions from the housing construction to its final disposal of a typical residential development in Saga, Japan. Results show that much of the environmental impacts from building a house are on the Global Warming Potential due to high carbon emissions. Moreover, the construction phase generated the highest pollutant emissions from nitrogen oxides, sulfur oxides and suspended particulate matter. Steel reinforced concrete (SRC) construction has a higher environmental impact compared to the wooden type of housing construction. A longer design life for a residential house gives a reduction of about 14% in carbon emissions. Using solar energy for the operation phase has gained a reduction of 73% in the total life cycle carbon emissions.     

Remote sensing of PM, NO, CO and HC emission factors for on-road gasoline and diesel engine vehicles in Las Vegas, NV

A novel light detection and ranging-based remote sensing system was assembled and used to measure mass particulate matter (PM) emissions per unit of fuel burned from in-use on-road vehicles. A commercially available remote sensing system was concurrently used to measure emissions of carbon monoxide (CO), nitrogen oxide (NO) and hydrocarbons (HC). The two systems were used to measure 61,207 gasoline and 1180 diesel powered vehicle emissions in Las Vegas, NV from 4/4/2000 to 5/16/2002. Emission factors were related to vehicle age, weight class and fuel type by matching license IDs to the state registration data. Measurements of vehicle speed and acceleration permitted the analysis of emission factors by vehicle specific power (VSP). Average emission factors were calculated for light-duty (<3863 kg [8500 lbs]) gasoline vehicles (LDGV), light-duty diesel vehicles (LDDV), heavy-duty (>3863 kg [8500 lbs]) gasoline vehicles (HDGV) and heavy-duty diesel vehicles (HDDV). LDDV and HDDV emitted approximately 25 times more PM per mass of fuel than LDGV and HDGV. Sufficient numbers of LDGV were measured to relate VSP with CO, HC and NO emissions. No relationship was observed between PM emissions and VSP. PM emission factors from LDGV increased with vehicle age. Fuel-based emission factors measured by remote sensing were compared with MOBILE6 and PART5 emissions model factors. Good agreement was observed for HC emission factors for vehicles less than 20 years old. MOBILE6 CO emission factors were approximately 2 times greater than measured CO emission factors for vehicles less than 13 years old. Measured NO emission factors were approximately 50% greater than MOBILE6 factors for vehicles 7-15 years old but in good agreement for vehicles less than 7 years old. Measured PM emission factors showed a clear increase with vehicle age, however, PART5 uses only a single PM emission factor for LDGV less than 18 years old. The PM emission factors for the fleet of LDGV, HDGV, LDDV and HDDV were 0.06, 0.05, 1.6 and 1.5 g/kg, respectively.     

混凝土与环境

应用生命周期评价法（LCA）,阐述和分析了与混凝土生产有关的环境问题,如废渣、废气和废水,以及能源、原材料、水和土地资源的消耗等,并对有可能引起的地球变暖和酸雨化等潜在的环境问题进行了探讨。该研究对合理利用资源,降低环境影响,保持国民经济可持续发展,具有十分重要的意义。