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1.
Eva-Mari Aro 《Ambio》2016,45(1):24-31
Roadmaps towards sustainable bioeconomy, including the production of biofuels, in many EU countries mostly rely on biomass use. However, although biomass is renewable, the efficiency of biomass production is too low to be able to fully replace the fossil fuels. The use of land for fuel production also introduces ethical problems in increasing the food price. Harvesting solar energy by the photosynthetic machinery of plants and autotrophic microorganisms is the basis for all biomass production. This paper describes current challenges and possibilities to sustainably increase the biomass production and highlights future technologies to further enhance biofuel production directly from sunlight. The biggest scientific breakthroughs are expected to rely on a new technology called “synthetic biology”, which makes engineering of biological systems possible. It will enable direct conversion of solar energy to a fuel from inexhaustible raw materials: sun light, water and CO2. In the future, such solar biofuels are expected to be produced in engineered photosynthetic microorganisms or in completely synthetic living factories.  相似文献   

2.
Use of biofuels as transport fuel has high prospect in developing countries as most of them are facing severe energy insecurity and have strong agricultural sector to support production of biofuels from energy crops. Rapid urbanization and economic growth of developing countries have spurred air pollution especially in road transport sector. The increasing demand of petroleum based fuels and their combustion in internal combustion (IC) engines have adverse effect on air quality, human health and global warming. Air pollution causes respiratory problems, adverse effects on pulmonary function, leading to increased sickness absenteeism and induces high health care service costs, premature birth and even mortality. Production of biofuels promises substantial improvement in air quality through reducing emission from biofuel operated automotives. Some of the developing countries have started biofuel production and utilization as transport fuel in local market. This paper critically reviews the facts and prospects of biofuel production and utilization in developing countries to reduce environmental pollution and petro dependency. Expansion of biofuel industries in developing countries can create more jobs and increase productivity by non-crop marginal lands and wastelands for energy crops plantation.Contribution of India and China in biofuel industry in production and utilization can dramatically change worldwide biofuel market and leap forward in carbon cut as their automotive market is rapidly increasing with a souring proportional rise of GHG emissions.  相似文献   

3.
Emissions from land transport, and from road transport in particular, have significant impacts on the atmosphere and on climate change. This assessment gives an overview of past, present and future emissions from land transport, of their impacts on the atmospheric composition and air quality, on human health and climate change and on options for mitigation.In the past vehicle exhaust emission control has successfully reduced emissions of nitrogen oxides, carbon monoxide, volatile organic compounds and particulate matter. This contributed to improved air quality and reduced health impacts in industrialised countries. In developing countries however, pollutant emissions have been growing strongly, adversely affecting many populations. In addition, ozone and particulate matter change the radiative balance and hence contribute to global warming on shorter time scales. Latest knowledge on the magnitude of land transport's impact on global warming is reviewed here.In the future, road transport's emissions of these pollutants are expected to stagnate and then decrease globally. This will then help to improve the air quality notably in developing countries. On the contrary, emissions of carbon dioxide and of halocarbons from mobile air conditioners have been globally increasing and are further expected to grow. Consequently, road transport's impact on climate is gaining in importance. The expected efficiency improvements of vehicles and the introduction of biofuels will not be sufficient to offset the expected strong growth in both, passenger and freight transportation. Technical measures could offer a significant reduction potential, but strong interventions would be needed as markets do not initiate the necessary changes. Further reductions would need a resolute expansion of low-carbon fuels, a tripling of vehicle fuel efficiency and a stagnation in absolute transport volumes. Land transport will remain a key sector in climate change mitigation during the next decades.  相似文献   

4.
A database of global agricultural primary production has been constructed and used to estimate its energy content. The portion of crops available for food and biofuel after postharvest losses was evaluated. The basic conditions for agriculture and plant growth were studied, to ensure sustainable scenarios regarding use of residues. The available energy contents for the world and EU27 was found to be 7,200–9,300 and 430 TWh, respectively, to be compared with food requirements of 7,100 and 530 TWh. Clearly, very little, or nothing, remains for biofuel from agricultural primary crops. However, by using residues and bioorganic waste, it was found that biofuel production could theoretically replace one-fourth of the global consumption of fossil fuels for transport. The expansion potential for global agriculture is limited by availability of land, water, and energy. A future decrease in supply of fossil energy and ongoing land degradation will thus cause difficulties for increased biofuel production from agriculture.  相似文献   

5.
Extensive production of ethanol and vehicular use of this biofuel have recently been suggested as possible sources of elevated volatile organic carbon (VOC) in rain in Brazil (Campos, M.L.A.M., Nogueira, R.F.P., Dametto, P.R., Francisco, J.G., Coelho, C.H., 2007. Dissolved organic carbon in rainwater: glassware decontamination and sample preservation and volatile organic carbon. Atmos. Environ. 41, 8924–8931; Coelho, C.H., Francisco, J.G., Nogueira, R.F.P., Campos, M.L.A.M., 2008. Dissolved organic carbon in rainwater from areas heavily impacted by sugar cane burning. Atmos. Environ. 42, 7115–7121). Furthermore, these studies suggested that the global flux of rainwater dissolved organic carbon (DOC) may be underestimated since most DOC analytical methods do not measure VOC. The current study examined rain VOC in Wilmington, North Carolina USA in order to assess the importance of rain VOC in a location that does not have the unique conditions of ethanol production and usage found in Brazil. VOC was observed in one of six whole rain events analyzed in the current study. This event had an air mass back trajectory that originated over the Midwestern USA, the primary region where ethanol is produced and used as fuel. The other five storms which had no influence from the central US prior to arrival at the rain collection site had non-detectable VOC suggesting that air mass back trajectory has a dramatic impact on the VOC content of rainwater. VOC was also observed in the initial 1 mm of rain from two of these events but was not detectable in the whole event samples suggesting VOC is efficiently washed out of the atmosphere and is not rapidly resupplied in rainwater at this location. Considering the results of the previous Brazilian studies and the current study, and the likelihood of increased global production and consumption of ethanol based biofuels, it is imperative that future measurements of rainwater DOC include measurement of VOC. Monitoring changes in the VOC contribution to rain DOC will provide an assessment of the impact of increased ethanol biofuel usage on rainwater composition and allow for future refinements of global rainwater DOC flux estimates.  相似文献   

6.
Before climate change is considered in long-term coastal management, it is necessary to investigate how institutional stakeholders in coastal management conceptualize climate change, as their awareness will ultimately affect their actions. Using questionnaires in eight Baltic Sea riparian countries, this study examines environmental managers' awareness of climate change. Our results indicate that problems related to global warming are deemed secondary to short-term social and economic issues. Respondents agree that problems caused by global warming will become increasingly important, but pay little attention to adaptation and mitigation strategies. Current environmental problems are expected to continue to be urgent in the future. We conclude that an apparent gap exists between decision making, public concerns, and scientific consensus, resulting in a situation in which the latest evidence rarely influences commonly held opinions.  相似文献   

7.
Sven Kullander 《Ambio》2010,39(3):249-256
Humankind is currently faced with the huge challenge of securing a sustainable energy supply and biofuels constitute one of the major options. However, the commercially traded edible crops are barely sufficient to meet food demand of the present world population. Certain regions, for example EU-27, do not even have a sufficient indigenous crop production. Of this follows that motor biofuels based on edible crops should be avoided. To replace more than some percent of the fossil motor fuels, non-edible biomass—rest products and wastes—should instead be considered for conversion to biofuels. In this way, about 10% of the current fossil fuels can be replaced. Feeding a world population expected to grow by some 50% during the next 50 years will be a major challenge. For environmental reasons it seems that agricultural land cannot be expanded very much, maybe not at all. The solution to the increasing food demand seems therefore to be using the present crop production more efficiently and increasing output from present agricultural land, maintaining biodiversity and climate stability within reasonable limits. In the future, agriculture will need more energy and more water irrigation. Food production is, however, already very energy demanding, requiring several times more externally provided energy than the energy content of the food itself. A sufficient energy supply will be a key issue for the future farming!  相似文献   

8.
Seafood from a changing Arctic   总被引:1,自引:0,他引:1  
We review current knowledge about climate change impacts on Arctic seafood production. Large-scale changes in the Arctic marine food web can be expected for the next 40–100 years. Possible future trajectories under climate change for Arctic capture fisheries anticipate the movement of aquatic species into new waters and changed the dynamics of existing species. Negative consequences are expected for some fish stocks but others like the Barents Sea cod (Gadus morhua) may instead increase. Arctic aquaculture that constitutes about 2% of global farming is mainly made up of Norwegian salmon (Salmo salar) farming. The sector will face many challenges in a warmer future and some of these are already a reality impacting negatively on salmon growth. Other more indirect effects from climate change are more uncertain with respect to impacts on the economic conditions of Arctic aquaculture.  相似文献   

9.
Humanity has entered a new phase of sustainability challenges, the Anthropocene, in which human development has reached a scale where it affects vital planetary processes. Under the pressure from a quadruple squeeze—from population and development pressures, the anthropogenic climate crisis, the anthropogenic ecosystem crisis, and the risk of deleterious tipping points in the Earth system—the degrees of freedom for sustainable human exploitation of planet Earth are severely restrained. It is in this reality that a new green revolution in world food production needs to occur, to attain food security and human development over the coming decades. Global freshwater resources are, and will increasingly be, a fundamental limiting factor in feeding the world. Current water vulnerabilities in the regions in most need of large agricultural productivity improvements are projected to increase under the pressure from global environmental change. The sustainability challenge for world agriculture has to be set within the new global sustainability context. We present new proposed sustainability criteria for world agriculture, where world food production systems are transformed in order to allow humanity to stay within the safe operating space of planetary boundaries. In order to secure global resilience and thereby raise the chances of planet Earth to remain in the current desired state, conducive for human development on the long-term, these planetary boundaries need to be respected. This calls for a triply green revolution, which not only more than doubles food production in many regions of the world, but which also is environmentally sustainable, and invests in the untapped opportunities to use green water in rainfed agriculture as a key source of future productivity enhancement. To achieve such a global transformation of agriculture, there is a need for more innovative options for water interventions at the landscape scale, accounting for both green and blue water, as well as a new focus on cross-scale interactions, feed-backs and risks for unwanted regime shifts in the agro-ecological landscape.  相似文献   

10.
Mounting research highlights the contribution of ecosystem services provided by urban forests to quality of life in cities, yet these services are rarely explicitly considered in environmental policy targets. We quantify regulating services provided by urban forests and evaluate their contribution to comply with policy targets of air quality and climate change mitigation in the municipality of Barcelona, Spain. We apply the i-Tree Eco model to quantify in biophysical and monetary terms the ecosystem services “air purification,” “global climate regulation,” and the ecosystem disservice “air pollution” associated with biogenic emissions. Our results show that the contribution of urban forests regulating services to abate pollution is substantial in absolute terms, yet modest when compared to overall city levels of air pollution and GHG emissions. We conclude that in order to be effective, green infrastructure-based efforts to offset urban pollution at the municipal level have to be coordinated with territorial policies at broader spatial scales.  相似文献   

11.
Emissions of exhaust gases and particles from oceangoing ships are a significant and growing contributor to the total emissions from the transportation sector. We present an assessment of the contribution of gaseous and particulate emissions from oceangoing shipping to anthropogenic emissions and air quality. We also assess the degradation in human health and climate change created by these emissions. Regulating ship emissions requires comprehensive knowledge of current fuel consumption and emissions, understanding of their impact on atmospheric composition and climate, and projections of potential future evolutions and mitigation options. Nearly 70% of ship emissions occur within 400 km of coastlines, causing air quality problems through the formation of ground-level ozone, sulphur emissions and particulate matter in coastal areas and harbours with heavy traffic. Furthermore, ozone and aerosol precursor emissions as well as their derivative species from ships may be transported in the atmosphere over several hundreds of kilometres, and thus contribute to air quality problems further inland, even though they are emitted at sea. In addition, ship emissions impact climate. Recent studies indicate that the cooling due to altered clouds far outweighs the warming effects from greenhouse gases such as carbon dioxide (CO2) or ozone from shipping, overall causing a negative present-day radiative forcing (RF). Current efforts to reduce sulphur and other pollutants from shipping may modify this. However, given the short residence time of sulphate compared to CO2, the climate response from sulphate is of the order decades while that of CO2 is centuries. The climatic trade-off between positive and negative radiative forcing is still a topic of scientific research, but from what is currently known, a simple cancellation of global mean forcing components is potentially inappropriate and a more comprehensive assessment metric is required. The CO2 equivalent emissions using the global temperature change potential (GTP) metric indicate that after 50 years the net global mean effect of current emissions is close to zero through cancellation of warming by CO2 and cooling by sulphate and nitrogen oxides.  相似文献   

12.

The international community is paying more attention to climate change because a consensus has been reached that climate change has an adverse effect not only on the environment but also on agriculture. Therefore, in this study, present and future climate datasets (obtained from general circulation models) including atmospheric carbon concentration were used to assess the impact of climate change on grain production for an important base of China (Northeast). An empirical model has been developed using climate and other additional variables (effective irrigation area, fertilizer, and labor force) to assess the effect of climate change on grain production. The results revealed that maximum temperature is a key climate determinant in grain production of the study area. Atmospheric carbon concentration showed a significant impact on grain outputs in most of the cases. During the analysis, it was observed that precipitation displayed a declining trend while an effective irrigation area showed positive non-significant contribution to grain production. Analysis based on different representative concentration pathways exhibited that maximum temperature may contribute negatively to grain production in the future. Overall, the analysis showed that climate change has a significant contribution to grain production. In conclusion, the implications for future research and policymakers have been addressed. Particularly, the importance of considering regional differences in adaptation planning in agricultural regions was also considered.

  相似文献   

13.
Global climate change: The quantifiable sustainability challenge   总被引:1,自引:0,他引:1  
Population growth and the pressures spawned by increasing demands for energy and resource-intensive goods, foods, and services are driving unsustainable growth in greenhouse gas (GHG) emissions. Recent GHG emission trends are consistent with worst-case scenarios of the previous decade. Dramatic and near-term emission reductions likely will be needed to ameliorate the potential deleterious impacts of climate change. To achieve such reductions, fundamental changes are required in the way that energy is generated and used. New technologies must be developed and deployed at a rapid rate. Advances in carbon capture and storage, renewable, nuclear, and transportation technologies are particularly important; however, global research and development efforts related to these technologies currently appear to fall short relative to needs. Even with a proactive and international mitigation effort, humanity will need to adapt to climate change, but the adaptation needs and damages will be far greater if mitigation activities are not pursued in earnest. In this review, research is highlighted that indicates increasing global and regional temperatures and ties climate changes to increasing GHG emissions. GHG mitigation targets necessary for limiting future global temperature increases are discussed, including how factors such as population growth and the growing energy intensity of the developing world will make these reduction targets more challenging. Potential technological pathways for meeting emission reduction targets are examined, barriers are discussed, and global and U.S. modeling results are presented that suggest that the necessary pathways will require radically transformed electric and mobile sectors. While geoengineering options have been proposed to allow more time for serious emission reductions, these measures are at the conceptual stage with many unanswered cost, environmental, and political issues.

Implications:?This paper lays out the case that mitigating the potential for catastrophic climate change will be a monumental challenge, requiring the global community to transform its energy system in an aggressive, coordinated, and timely manner. If this challenge is to be met, new technologies will have to be developed and deployed at a rapid rate. Advances in carbon capture and storage, renewable, nuclear, and transportation technologies are particularly important. Even with an aggressive international mitigation effort, humanity will still need to adapt to significant climate change.  相似文献   

14.
The on-road transportation (ORT) and power generation (PG) sectors are major contributors to carbon dioxide (CO2) emissions and a host of short-lived radiatively-active air pollutants, including tropospheric ozone and fine aerosol particles, that exert complex influences on global climate. Effective mitigation of global climate change necessitates action in these sectors for which technology change options exist or are being developed. Most assessments of possible energy change options to date have neglected non-CO2 air pollutant impacts on radiative forcing (RF). In a multi-pollutant approach, we apply a global atmospheric composition-climate model to quantify the total RF from the global and United States (U.S.) ORT and PG sectors. We assess the RF for 2 time horizons: 20- and 100-year that are relevant for understanding near-term and longer-term impacts of climate change, respectively. ORT is a key target sector to mitigate global climate change because the net non-CO2 RF is positive and acts to enhance considerably the CO2 warming impacts. We perform further sensitivity studies to assess the RF impacts of a potential major technology shift that would reduce ORT emissions by 50% with the replacement energy supplied either by a clean zero-emissions source (S1) or by the PG sector, which results in an estimated 20% penalty increase in emissions from this sector (S2). We examine cases where the technology shift is applied globally and in the U.S. only. The resultant RF relative to the present day control is negative (cooling) in all cases for both S1 and S2 scenarios, global and U.S. emissions, and 20- and 100-year time horizons. The net non-CO2 RF is always important relative to the CO2 RF and outweighs the CO2 RF response in the S2 scenario for both time horizons. Assessment of the full impacts of technology and policy strategies designed to mitigate global climate change must consider the climate effects of ozone and fine aerosol particles.  相似文献   

15.
Climate change is likely to be one of the most important factors affecting our future food security. To mitigate negative impacts, we will require our crops to be more genetically diverse. Such diversity is available in crop wild relatives (CWRs), the wild taxa relatively closely related to crops and from which diverse traits can be transferred to the crop. Conservation of such genetic resources resides within the nation where they are found; therefore, national-level conservation recommendations are fundamental to global food security. We investigate the potential impact of climate change on CWR richness in Norway. The consequences of a 1.5 and 3.0 °C temperature rise were studied for the years 2030, 2050, 2070, 2080 and then compared to the present climate. The results indicate a pattern of shifting CWR richness from the south to the north, with increases in taxa turnover and in the numbers of threatened taxa. Recommendations for in situ and ex situ conservation actions over the short and long term for the priority CWRs in Norway are presented. The methods and recommendations developed here can be applied within other nations and at regional and global levels to improve the effectiveness of conservation actions and help ensure global food security.  相似文献   

16.
Global change encompasses changes in atmospheric composition, climate and climate variability, and land cover and land use. The occurrence of these changes and their interactive effects on biological systems are worldwide; thus, an effective global change research and impact assessment program must be based on international and interdisciplinary research and communication. With this in mind, several collaborative research networks with a focus on global change have been established in the biological sciences. They include the Global Change and Terrestrial Ecosystems (GCTE) Core Project of the International Geosphere-Biosphere Programme (IGBP) which aims to predict the effects of global change on terrestrial ecosystems, including agriculture and production forestry. Because of the importance of plant pests (arthropods, microbial pathogens, weeds) as yield-reducing factors in agriculture and as early indicators of global change, GCTE initiated a network Activity on "Global Change Impacts on Pests, Diseases and Weeds" with the overall goal of developing a predictive capability for impact assessment and adaptation. The network's specific objectives, contributing research projects, initial results and future challenges are discussed.  相似文献   

17.
Transport affects climate directly and indirectly through mechanisms that operate on very different timescales and cause both warming and cooling. We calculate contributions to the historical development in global mean temperature for the main transport sectors (road transport, aviation, shipping and rail) based on estimates of historical emissions and by applying knowledge about the various forcing mechanisms from detailed studies. We also calculate the development in future global mean temperature for four transport scenarios consistent with the IPCC SRES scenarios, one mitigation scenario and one sensitivity test scenario. There are large differences between the transport sectors in terms of sign and magnitude of temperature effects and with respect to the contributions from the long- and short-lived components. Since pre-industrial times, we calculate that transport in total has contributed 9% of total net man-made warming in the year 2000. The dominating contributor to warming is CO2, followed by tropospheric O3. By sector, road transport is the largest contributor; 11% of the warming in 2000 is due to this sector. Likewise, aviation has contributed 4% and rail ~1%. Shipping, on the other hand, has caused a net cooling up to year 2000, with a contribution of ?7%, due to the effects of SO2 and NOx emissions. The total net contribution from the transport sectors to total man-made warming is ~15% in 2050, and reaches 20% in 2100 in the A1 and B1 scenarios. For all scenarios and throughout the century, road transport is the dominating contributor to warming. Due to the anticipated reduction in sulphur content of fuels, the net effect of shipping changes from cooling to warming by the end of the century. Significant uncertainties are related to the estimates of historical and future net warming mainly due to cirrus, contrails and aerosol effects, as well as uncertainty in climate sensitivity.  相似文献   

18.
Estuarine and shallow coastal systems (ESCS) are recognized as not only significant organic carbon reservoirs but also emitters of CO2 to the atmosphere through air–sea CO2 gas exchange, thus posing a dilemma on ESCS’s role in climate change mitigation measures. However, some studies have shown that coastal waters take up atmospheric CO2 (Catm), although the magnitude and determinants remain unclear. We argue that the phenomenon of net uptake of Catm by ESCS is not unusual under a given set of terrestrial inputs and geophysical conditions. We assessed the key properties of systems that show the net Catm uptake and found that they are often characteristic of human-dominated systems: (1) input of high terrestrial nutrients, (2) input of treated wastewater in which labile carbon is highly removed, and (3) presence of hypoxia. We propose that human-dominated ESCS are worthy of investigation as a contributor to climate change mitigation.  相似文献   

19.
We study changes in crop cover under future climate and socio-economic projections. This study is not only organised around the global and regional adaptation or vulnerability to climate change but also includes the influence of projected changes in socio-economic, technological and biophysical drivers, especially regional gross domestic product. The climatic data are obtained from simulations of RCP4.5 and 8.5 by four global circulation models/earth system models from 2000 to 2100. We use Random Forest, an empirical statistical model, to project the future crop cover. Our results show that, at the global scale, increases and decreases in crop cover cancel each other out. Crop cover in the Northern Hemisphere is projected to be impacted more by future climate than the in Southern Hemisphere because of the disparity in the warming rate and precipitation patterns between the two Hemispheres. We found that crop cover in temperate regions is projected to decrease more than in tropical regions. We identified regions of concern and opportunities for climate change adaptation and investment.  相似文献   

20.
A literature review and a survey of professionals whose work deals with climate change indicate that more is known and considered certain by the natural science community concerning responses of natural systems to climate change. There is less of a consensus among social scientists that social systems are directly responding to climate change. The emphasis in the literature on policy and mitigation is corroborated by the survey results, which revealed only social variables that are tightly linked to climate or natural systems. Identifying variables of both natural and social systems that respond to climate change is imperative for a better understanding of the implications of climate change.  相似文献   

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