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191.
Addressing food supply chain and consumption inefficiencies: potential for climate change mitigation
Globally, more than 30 % of all food that is produced is ultimately lost and/or wasted through inefficiencies in the food supply chain. In the developed world this wastage is centred on the last stage in the supply chain; the end-consumer throwing away food that is purchased but not eaten. In contrast, in the developing world the bulk of lost food occurs in the early stages of the supply chain (production, harvesting and distribution). Excess food consumption is a similarly inefficient use of global agricultural production; with almost 1 billion people now classed as obese, 842 million people are suffering from chronic hunger. Given the magnitude of greenhouse gas emissions from the agricultural sector, strategies that reduce food loss and wastage, or address excess caloric consumption, have great potential as effective tools in global climate change mitigation. Here, we examine the challenges of robust quantification of food wastage and consumption inefficiencies, and their associated greenhouse gas emissions, along the supply chain. We find that the quality and quantity of data are highly variable within and between geographical regions, with the greatest range tending to be associated with developing nations. Estimation of production-phase GHG emissions for food wastage and excess consumption is found to be similarly challenging on a global scale, with use of IPCC default (Tier 1) emission factors for food production being required in many regions. Where robust food waste data and production-phase emission factors do exist—such as for the UK—we find that avoiding consumer-phase food waste can deliver significant up-stream reductions in GHG emissions from the agricultural sector. Eliminating consumer milk waste in the UK alone could mitigate up to 200 Gg CO2e year?1; scaled up globally, we estimate mitigation potential of over 25,000 Gg CO2e year?1. 相似文献
192.
Nicole Mölders Stacy E. Porter Catherine F. Cahill Georg A. Grell 《Atmospheric environment (Oxford, England : 1994)》2010,44(11):1400-1413
The impact of ship emissions on air quality in Alaska National Parks and Wilderness Areas was investigated using the Weather Research and Forecasting model inline coupled with chemistry (WRF/Chem). The visibility and deposition of atmospheric contaminants was analyzed for the length of the 2006 tourist season. WRF/Chem reproduced the meteorological situation well. It seems to have captured the temporal behavior of aerosol concentrations when compared with the few data available. Air quality follows certain predetermined patterns associated with local meteorological conditions and ship emissions. Ship emissions have maximum impacts in Prince William Sound where topography and decaying lows trap pollutants. Along sea-lanes and adjacent coastal areas, NOx, SO2, O3, PAN, HNO3, and PM2.5 increase up to 650 pptv, 325 pptv, 900 pptv, 18 pptv, 10 pptv, and 100 ng m?3. Some of these increases are significant (95% confidence). Enhanced particulate matter concentrations from ship emissions reduce visibility up to 30% in Prince William Sound and 5–25% along sea-lanes. 相似文献
193.
Jodi D. Hoffman Diana W. Bianchi Lisa M. Sullivan Brenda L. Mackinnon Jamie Collins Fergal D. Malone T. Flint Porter David A. Nyberg Christine H. Comstock Radek Bukowski Richard L. Berkowitz Susan J. Gross Lorraine Dugoff Sabrina D. Craigo Ilan E. Timor-Tritsch Stephen R. Carr Honor M. Wolfe Mary E. D'Alton 《黑龙江环境通报》2008,28(13):1204-1208
194.
随着我国红色旅游业的快速发展,以翻译为主要途径的外宣工作的重要性日益彰显,如何评价外宣文本的可读性逐渐成为学界关注的热点问题。文中以井冈山景区的英译文本为例,通过问卷调查和访谈的方式收集了十五位目标语读者关于外宣文本的反馈意见。结果显示:译文的可读性受文本质量、文本长度和读者背景等诸多因素的影响。由于译者对英译文本的目标语读者和文本功能认识不足,译文在词汇、语句和语篇等层面均存在不同程度的问题。 相似文献
195.
David A. Storey Daniel A. Lass Joseph Diamond Bruce E. Lindsay 《Journal of the American Water Resources Association》1982,18(3):409-414
ABSTRACT: Under the terms of the Thames River Valley Flood Control Compact, Connecticut has been paying Massachusetts 40 percent of the annual property tax losses suffered by seven Massachusetts towns where four flood control structures were located. The permissable alternative of a single lump sum payment was investigated in the study summarized here. The lump sum payment should be the proportion of total benefits (flood control and recreation) from the four structures which Connecticut receives, multiplied by the present value of projected tax losses in the seven tom Flood control benefits and their distribution between the two states were fixed in the Compact, but a survey was necessary to determine recreational benefits and their distribution. Regression analysis of 1957 to 1978 tax loss data provided equations used to project future tax losses. Resent values of projected tax low were calculated using discount rates ranging from 6 to 12 percent. A plausible range of lump sum reinbursements as of 1979 was identified. 相似文献
196.
197.
L. K. Porter 《Journal of contaminant hydrology》1995,20(3-4)
Deep percolation of nitrate can contribute to the deterioration of groundwater resources. Leaching of nitrate is a complex process affected by fertilizer and irrigation practices, efficiency of N use by the crop, and how the soil's water holding capacity and water transmission properties are affected by soil texture. Depleted (15NH4)2SO4 fertilizer at N rates of 0, 125, 250 and 375 kg ha−1 was applied annually for 3 years to continuous corn grown within three different water regimes. This time period and the labeled N permitted an evaluation of N use efficiency by the crop and NO3 leaching and carryover on a Weld silty clay loam, a fine-textured soil, typical of the “hardland” soils of the semi-arid Great Plains. Three water regimes, W1 ( 1.5 ET), W2 ( ET) and W3 ( 0.8 ET), were used. Beneath each plot within each water regime, Duke-Haise vacuum trough extractors were installed under undisturbed soil profiles at 1.22-m depth to measure weekly percolate and the NO3 concentration in the percolate. The corn was harvested in the fall in the dent stage to measure the total above-ground biomass N uptake. Soil profiles (1.8 m) were sampled annually in the fall after crop harvest to determine NO3---N in the soil or carryover.Great variability was encountered in measuring the amount of extractor water and its NO3 content under each water regime, which made estimates of N03 leaching losses unreliable. Also, the variability demonstrates formidable problems in quantifying percolation losses with vacuum trough extractors under undisturbed fine-textured soil profiles. With the highest N rate of 376 kg ha−1 yr−1 and within the water regime W1, where leaching was expected to be greatest, only 1% of the cumulative labeled N applied was found in extractor waters and most movement of the labeled N into extractors occurred the third year. The 125-kg-ha−1 yr−1 fertilizer N rate significantly increased the crop yield over the unfertilized plots without increasing residual NO3---N accumulation; whereas fertilizer N rates of > 125 kg ha−1 yr−1 did not appreciably increase plant yields over the 125-kg-ha−1-N rate, but did appreciably increase residual NO3. 相似文献
198.
This paper reviews the use of ion exchange resins for adsorbing proteins and viruses and for purifying viral suspensions. The analysis of resin performance under different conditions provides some information on the fundamental nature of virus/protein-resin interaction.A variety of systems are considered and the influence of factors such as resin type, resin pretreatment, chemical characteristics of the solution and virus type on adsorption are discussed and compared. Analogies are made between virus-host and virus-resin interactions, both of which are specific to the virus-host or virus-resin pair. Consideration is given to the use of proteins as models for virus adsorption. The use of viral parameters such as iso-electric point and the amino acid content of the protein coat for predicting virus adsorption behavior is also discussed. Anion exchange resins were found to be more effective virus sorbents than cation exchange resins. Cation exchange resins were ineffective in low ionic strength media, while anion exchange resins were most effective in low ionic strength media. 相似文献
199.
Arlindo Canigo Gomes Isolina Cabral Gon?alves Maria Norberta de Pinho John Jefferson Porter 《Water environment research》2007,79(5):498-506
The filtration characteristics of simulated dyeing effluents containing Acid Orange 7, sodium sulfate, and a pH buffer made of acetic acid and sodium acetate is described using a commercially available nanofiltration membrane. The original membrane filtration properties were characterized with deionized water to provide a baseline of membrane performance. At high volumetric concentration of the test solutions, greater than 98% rejection of dye and sodium sulfate were obtained. Rejection of buffering chemicals was approximately 50% in all experiments, giving a permeate water not suitable for reuse in most dyeing operations. The final composite concentrate had a chemical oxygen demand (COD) value > 2000 mg/L. No problems were encountered with anaerobic treatment of the concentrate obtained from the dyeing wastewater. Adjusting the sulfate concentration to give COD-to-sulfate ratios to 2.9, 5.4, and 18.2 in the reactor feed had no significant alterations in the performance of the upflow anaerobic sludge blanket reactor. 相似文献
200.
McFarland MJ Palmer GR Kordich MM Pollet DA Jensen JA Lindsay MH 《Journal of the Air & Waste Management Association (1995)》2005,55(8):1111-1121
The U.S. Department of Defense approved activities conducted at the Utah Test and Training Range (UTTR) include both operational readiness test firing of intercontinental ballistic missile motors as well as the destruction of obsolete or otherwise unusable intercontinental ballistic missile motors through open burn/open detonation (OB/ OD). Within the Utah Division of Air Quality, these activities have been identified as having the potential to generate unacceptable noise levels, as well as significant amounts of hazardous air pollutants. Hill Air Force Base, UT, has completed a series of field tests at the UTTR in which sound-monitoring surveillance of OB/OD activities was conducted to validate the Sound Intensity Prediction System (SIPS) model. Using results generated by the SIPS model to support the decision to detonate, the UTTR successfully disposed of missile motors having an aggregate net explosive weight (NEW) of 56,500 lbs without generating adverse noise levels within populated areas. These results suggest that, under appropriate conditions, missile motors of even larger NEW may be detonated without exceeding regulatory noise limits. In conjunction with collecting noise monitoring data, air quality data was collected to support the development of air emission factors for both static missile motor firings and OB/OD activities. Through the installation of 15 ground-based air samplers, the generation of combustion fixed gases, hazardous air pollutants, and chlorides were monitored during the 56,500-lb NEW detonation event. Comparison of field measurements to predictions generated from the U.S. Navy's energetic combustion pollutant formation model, POLU4WN, indicated that, as the detonation fireball expanded from ground zero, organic compounds as well as carbon monoxide continued to oxidize as the hot gases reacted with ambient air. Hazardous air pollutant analysis of air samplers confirmed the presence of chloromethane, benzene, toluene, 1,2-propadiene, and 2-methyl-l-propene, whereas the absence of hydrogen chloride gas suggested that free chlorine is not generated during the combustion process. 相似文献