共查询到20条相似文献,搜索用时 622 毫秒
1.
Bernd Lengers Inga Schiefler Wolfgang Büscher 《Environmental monitoring and assessment》2013,185(12):9751-9762
The overall measurement of farm level greenhouse gas (GHG) emissions in dairy production is not feasible, from either an engineering or administrative point of view. Instead, computational model systems are used to generate emission inventories, demanding a validation by measurement data. This paper tests the GHG calculation of the dairy farm-level optimization model DAIRYDYN, including methane (CH4) from enteric fermentation and managed manure. The model involves four emission calculation procedures (indicators), differing in the aggregation level of relevant input variables. The corresponding emission factors used by the indicators range from default per cow (activity level) emissions up to emission factors based on feed intake, manure amount, and milk production intensity. For validation of the CH4 accounting of the model, 1-year CH4 measurements of an experimental free-stall dairy farm in Germany are compared to model simulation results. An advantage of this interdisciplinary study is given by the correspondence of the model parameterization and simulation horizon with the experimental farm’s characteristics and measurement period. The results clarify that modeled emission inventories (2,898, 4,637, 4,247, and 3,600 kg CO2-eq. cow?1 year?1) lead to more or less good approximations of online measurements (average 3,845 kg CO2-eq. cow?1 year?1 (±275 owing to manure management)) depending on the indicator utilized. The more farm-specific characteristics are used by the GHG indicator; the lower is the bias of the modeled emissions. Results underline that an accurate emission calculation procedure should capture differences in energy intake, owing to milk production intensity as well as manure storage time. Despite the differences between indicator estimates, the deviation of modeled GHGs using detailed indicators in DAIRYDYN from on-farm measurements is relatively low (between ?6.4 % and 10.5 %), compared with findings from the literature. 相似文献
2.
Beniamino Gioli Maria F. Carfora Vincenzo Magliulo Maria C. Metallo Attilio A. Poli Piero Toscano Franco Miglietta 《Environmental monitoring and assessment》2014,186(4):2053-2066
Aircraft measurements were used to estimate the CO2 emission rates of the city of Rome, assessed against high-resolution inventorial data. Three experimental flights were made, composed of vertical soundings to measure Planetary Boundary Layer (PBL) properties, and circular horizontal transects at various altitudes around the city area. City level emissions and associated uncertainties were computed by means of mass budgeting techniques, obtaining a positive net CO2 flux of 14.7?±?4.5, 2.5?±?1.2, and 10.3?±?1.2 μmol m?2 s?1 for the three flights. Inventorial CO2 fluxes at the time of flights were computed by means of spatial and temporal disaggregation of the gross emission inventory, at 10.9?±?2.5, 9.6?±?1.3, and 17.4?±?9.6 μmol m?2 s?1. The largest differences between the two dataset are associated with a greater variability of wind speed and direction in the boundary layer during measurements. Uncertainty partitioned into components related to horizontal boundary flows and top surface flow, revealed that the latter dominates total uncertainty in the presence of a wide variability of CO2 concentration in the free troposphere (up to 7 ppm), while it is a minor term with uniform tropospheric concentrations in the study area (within 2 ppm). Overall, we demonstrate how small aircraft may provide city level emission measurements that may integrate and validate emission inventories. Optimal atmospheric conditions and measurement strategies for the deployment of aircraft experimental flights are finally discussed. 相似文献
3.
A. O. Isichei J. I. Muoghalu F. A. Akeredolu O. A. Afolabi 《Environmental monitoring and assessment》1995,38(2-3):279-289
Nigeria is one of the 13 low-latitude countries that have significant biomass burning activities. Biomass burning occurs in moist savanna, dry forests, and forest plantations. Fires in the forest zone are associated with slash-and-burn agriculture; the areal extent of burning is estimated to be 80% of the natural savanna. In forest plantations, close to 100% of litter is burned. Current estimates of emissions from land-use change are based on a 1976 national study and extrapolations from it. The following non-carbon dioxide (CO2) trace gas emissions were calculated from savanna burning: methane (CH4), 145 gigagrams (Gg); carbon monoxide (CO), 3831 Gg; nitrous oxide (N2O), 2 Gg; and nitrogen oxides (NOx), 49 Gg. Deforestation rates in forests and woodlands are 300 × 103 ha (kilohectare, or kha) and 200 × kha per year, respectively. Trace gas emissions from deforestation were estimated to be 300 Gg CH4, 2.4 Gg N2O, and 24 Gg NOx. CO2 emissions from burning, decay of biomass, and long-term emissions from soil totaled 125 561 Gg. These estimates should be viewed as preliminary, because greenhouse gas emission inventories from burning, deforestation, and land-use change require two components: fuel load and emission factors. Fuel load is dependent on the areal extent of various land uses, and the biomass stocking and some of these data in Nigeria are highly uncertain. 相似文献
4.
Y. Sokona 《Environmental monitoring and assessment》1995,38(2-3):291-299
The first greenhouse gas (GHG) emission estimates for Senegal, for the year 1991, were produced according to the draft IPCC/OECD guidelines for national inventories of GHGs. Despite certain discrepancies, nonavailability of data, the quality of some of the data collected, and the methodology, the estimates provide a provisional basis for Senegal to fulfill its obligations under the UN Framework Convention on Climate Change. This inventory reveals that GHG emissions in Senegal, like those in many developing countries, can mainly be attributed to the use of biomass for energy, land-use change and forestry, and savanna burning. Taking into account the direct global warming potential of the main GHGs (CO2, CH4, and N2O), Senegal's emissions are estimated at 17.6 Tg ECO2. The major gases emitted are CO2 (61% of GHG emissions), followed by CH4 (35%) and N2O (4%). Energy accounts for 45% of total emissions (12% from fossil energy and 33% from traditional biomass energy); land-use change and forests, 18%; agriculture, 24%; waste, 12%; and industry, 1%. 相似文献
5.
Emissions of soil CO2 under different management systems have a significant effect on the carbon balance in the atmosphere. Soil CO2 emissions were measured from an apricot orchard at two different locations: under the crown of trees (CO2-UC) and between tree rows (CO2-BR). For comparison, one other measurement was performed on bare soil (CO2-BS) located next to the orchard field. Analytical data were obtained weekly during 8 years from April 2008 to December 2016. Various environmental parameters such as air temperature, soil temperature at different depths, soil moisture, rainfall, and relative humidity were used for modeling and estimating the long-term seasonal variations in soil CO2 emissions using two different methods: generalized linear model (GLM) and artificial neural network (ANN). Before modeling, data were randomly split into two parts, one for calibration and the second for validation, with a varying number of samples in each part. Performances of the models were compared and evaluated using means absolute of estimations (MAE), square root of mean of prediction (RMSEP), and coefficient of determination (R2) values. CO2-UC, CO2-BR, and CO2-BS values ranged from 11 to 3985, from 9 to 2365, and from 8 to 1722 kg ha?1 week?1, respectively. Soil CO2 emissions were significantly correlated (p?<?0.05) with some environmental variables. The results showed that GLM and ANN models provided similar accuracies in modeling and estimating soil CO2 emissions, as the number of samples in the validation data set increased. The ANN was more advantageous than GLM models by providing a better fit between actual observations and predictions and lower RMSEP and MAE values. The results suggested that the success of environmental variables for estimations of CO2 emissions using the two methods was moderate. 相似文献
6.
In order to arrive at transparent and comparable inventories, the IPCC, in cooperation with the OECD, is currently developing a common methodology and reporting guidelines for the estimation of anthropogenic greenhouse gas emissions. To gain experience with the IPCC methodology, inventories are currently being carried out in various countries. This paper describes the African experience regarding emission inventories and preliminary results of the studies. It focuses on several important sources of non-CO2 greenhouse gas emissions in Africa: biomass burning; rice cultivation; and animals. 相似文献
7.
Accurate emission inventory (EI) is the foremost requirement for air quality management. Specifically, air quality modeling
requires EI with adequate spatial and temporal distributions. The development of such EI is always challenging, especially
for sporadic emission sources such as biomass open burning. The country of Thailand produces a large amount of various crops
annually, of which rough (unmilled) rice alone accounted for over 30 million tonnes in 2007. The crop residues are normally
burned in the field that generates large emissions of air pollutants and climate forcers. We present here an attempt at a
multipollutant EI for crop residue field burning in Thailand. Available country-specific and regional primary data were thoroughly
scrutinized to select the most realistic values for the best, low and high emission estimates. In the base year of 2007, the
best emission estimates in Gigagrams were as follows: particulate matter as PM2.5, 128; particulate matter as PM10, 143; sulfur dioxide (SO2), 4; carbon dioxide (CO2), 21,400; carbon monoxide (CO), 1,453; oxides of nitrogen (NOx), 42; ammonia (NH3), 59; methane (CH4), 132; non-methane volatile organic compounds (NMVOC), 108; elemental carbon (EC), 10; and organic carbon (OC), 54. Rice
straw burning was by far the largest contributor to the total emissions, especially during the dry season and in the central
part of the country. Only a limited number of EIs for crop residue open burning were reported for Thailand but with significant
discrepancies. Our best estimates were comparable but generally higher than other studies. Analysis for emission uncertainty,
taking into account possible variations in activity data and emission factors, shows considerable gaps between low and high
estimates. The difference between the low and high EI estimates for particulate matter and for particulate EC and OC varied
between −80% and +80% while those for CO2 and CO varied between −60% and +230%. Further, the crop production data of Thailand were used as a proxy to disaggregate
the emissions to obtain spatial (76 provinces) and temporal (monthly) distribution. The provincial emissions were also disaggregated
on a 0.1° × 0.1° grid net and to hourly profiles that can be directly used for dispersion modeling. 相似文献
8.
Verifying emission factors and national POPs emission inventories for the UK using measurements and modelling at two rural locations 总被引:2,自引:0,他引:2
Lohmann R Lee RG Abbott J Coleman P Jones KC 《Journal of environmental monitoring : JEM》2006,8(1):79-88
Different approaches are used to verify the adequacy of emission factors (EFs) and their use in emission inventories of persistent organic pollutants (POPs). The applicability of EFs was tested using atmospheric dispersion modelling to predict atmospheric concentrations of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) and resulting toxic equivalents (SigmaTEQ) and particulate matter <10 microm (PM(10)) in two rural locations in northern England (UK). The modelling was based on general assumptions of fuel composition, consumption and heating needs to simulate emissions of POPs from the domestic burning of coal and wood where ambient measurements were made in the winter of 1998. The model was used to derive the local contribution to ambient air concentrations, which were estimated independently based on comparative air measurements. The results support the hypothesis that in both villages, the majority of PAHs and the lower chlorinated PCDFs were locally released. The situation for PCBs and polychlorinated naphthalenes (PCNs) was different. While the EFs show the release of both compound groups from the domestic burning of coal and wood, the ambient levels of these "legacy POPs" in the villages were still clearly dominated by other sources. Rural areas relying mainly on fossil fuels can exceed the proposed UK ambient air quality standard for benzo[a]pyrene during winter. The measured EFs were then used to estimate the importance of the domestic burning of coal and wood to national emission inventories for these compound classes. Extrapolations to the UK suggest that the domestic burning of pure wood and coal were minor emitters for chlorinated POPs but contributed strongly to PAH and PM(10) levels in 2000. Finally, the UK's national POPs emission inventories based on source inventories and EF, as used here, were compared to estimates derived using the increase in atmospheric concentration of selected POPs. 相似文献
9.
Moti L. Mittal Chhemendra Sharma Richa Singh 《Environmental monitoring and assessment》2014,186(10):6857-6866
This study aims to estimate the emissions of carbon dioxide (CO2), sulfur dioxide (SO2), and nitric oxide (NO) for coal combustion in thermal power plants in India using plant-specific emission factors during the period of 2001/02 to 2009/10. The mass emission factors have been theoretically calculated using the basic principles of combustion under representative prevailing operating conditions in the plants and fuel composition. The results show that from 2001/02 to 2009/10 period, total CO2 emissions have increased from 324 to 499 Mt/year; SO2 emissions have increased from 2,519 to 3,840 kt/year; and NO emissions have increased from 948 to 1,539 kt/year from the Indian coal-fired power plants. National average emissions per unit of electricity from the power plants do not show a noticeable improvement during this period. Emission efficiencies for new plants that use improved technology are found to be better than those of old plants. As per these estimates, the national average of CO2 emissions per unit of electricity varies between 0.91 and 0.95 kg/kWh while SO2 and NO emissions vary in the range of 6.9 to 7.3 and 2.8 to 2.9 g/kWh, respectively. Yamunagar plant in Haryana state showed the highest emission efficiencies with CO2 emissions as 0.58 kg/kWh, SO2 emissions as 3.87 g/kWh, and NO emissions as 1.78 g/kWh, while the Faridabad plant has the lowest emission efficiencies with CO2 emissions as 1.5 kg/kWh, SO2 emissions as 10.56 g/kWh, and NO emissions as 4.85 g/kWh. Emission values at other plants vary between the values of these two plants. 相似文献
10.
B. C. Nguyen J. P. Putaud N. Mihalopoulos B. Bonsang C. Doan 《Environmental monitoring and assessment》1994,31(1-2):131-137
Atmospheric samples collected during rice straw burning at four different locations in Viet-Nam during the dry (March 1992, February 1993) and wet season (August 1992) were analysed for CO2, CO, and CH4. The emission ratios relative to CO2 for CO and CH4 for rice straw burning during the dry season were comparable to those observed on samples collected during burning of savanna in Africa or forest in the USA. During the wet season, however the emission ratios for CO and CH4 relative to CO2 were 3 to 10 times higher. With these emission ratios and estimates of rice production from Southeastern Asia, we estimated that burning of rice straw emits annually about 2.2 Tmol of CO (26 TgC) and 0.2 Tmol of CH4 (2.4 TgC) to the atmosphere. Taking into account these new results, CO and CH4 fluxes from biomass burning could be reevaluated by 5–21% and 5–24%, respectively, in respect with previous estimates of these gas emissions from all biomass burning activities. 相似文献
11.
Ground-level concentrations of carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) were monitored over three seasons, i.e., post-monsoon (September–October), winter (January–February), and summer (May–June) for 1 year during 2013–2014 in Nagpur City in India. The selected gases had moderate to high variation both spatially (residential, commercial, traffic intersections, residential cum commercial sites) and temporally (at 7:00, 13:00, 18:00, and 23:00 hours in all three seasons). Concentrations of gases were randomly distributed diurnally over city in all seasons, and there was no specific increasing or decreasing trend with time in a day. Average CO2 and N2O concentrations in winter were higher over post-monsoon and summer while CH4 had highest average concentration in summer. Observed concentrations of CO2 were predominantly above global average of 400 ppmv while N2O and CH4 concentrations frequently dropped down below global average of 327 ppbv and 1.8 ppmv, respectively. Two-tailed Student’s t test indicated that post-monsoon CO2 concentrations were statistically different from summer but not so from winter, while difference between summer and winter concentrations was statistically significant (P < 0.05). CH4 concentrations in all seasons were statistically at par to each other. In case of N2O, concentrations in post-monsoon were statistically different from summer but not so from winter, while difference between summer and winter concentrations was statistically significant (P < 0.05). Average ground-level concentrations of the gases calculated for three seasons together were higher in commercial areas. Environmental management priorities vis a vis greenhouse gas emissions in the city are also discussed. 相似文献
12.
为验证二氧化碳排放量的测试技术适用性及可行性,获取燃煤电厂机组碳排放特征,系统比较不同测试方法之间碳排放量的差异,对某典型火电机组二氧化碳排放开展测试,结果表明,不同测试原理及设备二氧化碳排放实测体积分数均较为接近。测试机组CO2实测体积分数为11.28%~14.21%,与负荷变化呈一定的正相关关系,不同负荷下基准氧含量(体积分数6%)基本无变化。测试机组排放量与负荷正相关,使用了缺省值的指南排放量最高,与其他方法排放量相对偏差均值为31.6%;使用入炉煤实测数据的指南排放量差异不大,相对偏差为0.1%;使用入炉煤实测数据的2版指南排放量高于直接测量法,相对偏差均值为4.9%;直接测量各类方法间相对偏差均值为1.0%,其中在线法与手工法间相对偏差均值为1.2%。CO2排放强度与负荷负相关,实验条件下,机组负荷越高,碳排放强度越低。 相似文献
13.
Infrared spectrometry is a versatile basis to analyse greenhouse gases in the atmosphere. A multicomponent air pollution software (MAPS) was developed for retrieval of gas concentrations from radiation emission as well as absorption measurements. Concentrations of CO, CH4, N2O, and H2O as well as CO2, NO, NO2, NH3, SO2, HCl, HCHO, and the temperature of warm gases are determined on-line. The analyses of greenhouse gases in gaseous emission sources and in ambient air are performed by a mobile remote sensing system using the double-pendulum interferometer K300 of the Munich company Kayser-Threde. Passive radiation measurements are performed to retrieve CO, N2O, and H2O as well as CO2, NO, SO2, and HCl concentrations in smoke stack effluents of thermal power plants and municipal incinerators and CO and H2O as well as CO2 and NO in exhausts of aircraft engines. Open-path radiation measurements are used to determine greenhouse gas concentrations at different ambient air conditions and greenhouse gas emission rates of diffusive sources as garbage deposits, open coal mining, stock farming together with additional compounds (e.g. NH3), and from road traffic together with HCHO. Some results of measurements are shown. A future task is the verification of emission cadastres by these inspection measurements. 相似文献
14.
David S. Pal Rajan Tripathee Matthew C. Reid Karina V. R. Schäfer Peter R. Jaffé 《Environmental monitoring and assessment》2018,190(3):176
Biogeochemical processes in wetland soils are complex and are driven by a microbiological community that competes for resources and affects the soil chemistry. Depending on the availability of various electron acceptors, the high carbon input to wetland soils can make them important sources of methane production and emissions. There are two significant pathways for methanogenesis: acetoclastic and hydrogenotrophic methanogenesis. The hydrogenotrophic pathway is dependent on the availability of dissolved hydrogen gas (H2), and there is significant competition for available H2. This study presents simultaneous measurements of dissolved methane and H2 over a 2-year period at three tidal marshes in the New Jersey Meadowlands. Methane reservoirs show a significant correlation with dissolved organic carbon, temperature, and methane emissions, whereas the H2 concentrations measured with dialysis samplers do not show significant relationships with these field variables. Data presented in this study show that increased dissolved H2 reservoirs in wetland soils correlate with decreased methane reservoirs, which is consistent with studies that have shown that elevated levels of H2 inhibit methane production by inhibiting propionate fermentation, resulting in less acetate production and hence decreasing the contribution of acetoclastic methanogenesis to the overall production of methane. 相似文献
15.
Monitoring and dispersion modelling of emissions from the fluidised bed combustion of poultry litter
Henihan AM Kelleher BP Leahy MJ Cummins E Leahy JJ 《Environmental monitoring and assessment》2003,85(3):239-255
Gaseous emissions from the fluidised bed combustion of chickenlitter were monitored and recorded. Emission data was used tocreate a dispersion model for a proposed site on a poultry farmin Limerick, Ireland. Variables within the combustion unit notonly influenced combustion but also emission levels ofpollutants such as SO2 and NOx. CO emissions decreased withuse of the correct ratio between fluidising and secondary air,the staging of secondary air and the degree of turbulence withwhich the secondary air is introduced. Dispersion modelling ofactual combustion at a proposed poultry unit predicted thatground level concentrations for the set of emissions data wouldbe below the limits and guidelines set by air quality standards.This was true for both and line source. Line sourceconcentration levels were less than those for point source. 相似文献
16.
17.
María A. Rubio Irene Fuenzalida Elizabeth Salinas Eduardo Lissi Ralf Kurtenbach Peter Wiesen 《Environmental monitoring and assessment》2010,162(1-4):209-217
CO/CO2 ratios have been measured in different locations of Santiago de Chile city. Measurements were carried out in a tunnel (prevailing emissions from cars with catalytic converter) and close to heavy traffic streets. Concentrations measured along the city traffic tunnel or temporal profiles of concentrations measured near heavy traffic streets allow an estimation of CO/CO2 ratios emitted from mobile sources. Values obtained range from 0.0045 ± 0.0006 to 0.0100 ± 0.0004 and depend on the prevailing type of mobile sources. In particular, lowest values were found close to a street with heavy traffic dominated by diesel-powered public transportation, while the highest values were found at the city tunnel. Places located near streets of mixed mobile sources (public buses and cars) showed intermediate values. Average CO/CO2 ratios are compatible with emission factors proposed for Santiago’s main mobile sources. 相似文献
18.
南通市温室气体排放估算 总被引:1,自引:1,他引:0
以2009年南通市主要领域碳排放情况为基数,采用IPCC指南中的计算方法,选取IPCC 指南明确的领域中对南通市而言具有代表性的部分内容,对2009年南通市全市碳排放量进行估算。估算结果表明,能源活动(化石燃料燃烧)为南通市主要温室气体排放源,其比例占据了主导地位。在能源活动中,原煤燃烧排放的CO2远高于其他化石燃料燃烧的排放量。因此,南通市可在产业结构和能源结构调整、提高能源利用效率及加强能源管理等方面进行努力,以减少南通市温室气体排放量。 相似文献
19.
Clare Paton-Walsh Stephen R. Wilson Travis Naylor David W. T. Griffith O. T. Denmead 《Environmental Modeling and Assessment》2011,16(5):441-452
The Great Barrier Reef World Heritage Area contains highly sensitive ecosystems that are threatened by the effects of anthropogenic
activity including eutrophication. The nearby sugarcane plantations of tropical north Queensland are fertilised annually and
there has been ongoing concern about the magnitude of the loss of applied nitrogen to the environment. Previous studies have
considered the potential of rainwater run-off to deposit reactive nitrogen species into rivers and ultimately into the Great
Barrier Reef Lagoon, but have neglected the possibility of transport via the atmosphere. This paper reports the results of
a modelling study commissioned by Australia’s National Heritage Trust aimed at assessing whether or not atmospheric deposition
of reactive nitrogen from Queensland’s sugarcane plantations posed a potential threat to the Great Barrier Reef Lagoon. Atmospheric
dispersion modelling was undertaken using The Air Pollution Model, developed by Australia’s Commonwealth Scientific and Industrial
Research Organisation. Despite the predominance of onshore southeasterly winds, the dispersion model results indicate that
9% of the time during the sugarcane fertilization season (in the modeled years 2001–2006) the meteorological conditions resulted
in emissions from the coastal regions of north Queensland being transported out over the ocean around the Great Barrier Reef.
The results suggest that there may be a greater efficiency for transport out over the reef during October than for November
and December. For the 2 months that exhibited the greatest potential for transport of coastal pollution to the Great Barrier
Reef, the modeled deposition of nitrogen oxides (NOX) into the Great Barrier Reef lagoon was less than 1% of the total emissions from the sugarcane plantations, but was not zero.
Our model has a simple chemical scheme that does not cover the full chemistry of all reactive nitrogen compounds and so the
results are only indicative of the potential levels of deposition. Nevertheless, our study shows that small amounts of NOX that originate from sugarcane fertilization may be transported and dry deposited into the Great Barrier Reef lagoon. Other
pathways not included in the modeling scheme may provide a more efficient transport mechanism. Whilst modern practices for
the application of fertilizer to sugarcane plantations have drastically reduced emissions, the potential efficiency of transport
of pollutants via the atmosphere may be of concern for other more highly polluting agricultural industries. 相似文献
20.
A cost-efficient way to allocate carbon dioxide (CO2) emission reductions among countries or regions is to harmonise their marginal reduction costs. This could be achieved by a market of emission reduction units (ERUs). To model such a market, we use a multi-regional MARKAL-MACRO model. It gives insights into the consequences of co-ordinating CO2 abatement on regional energy systems and economies. As a numerical application, we assess the establishment of a market of ERUs among three European countries for curbing their CO2 emissions. 相似文献