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1.
The possibility of adopting national targets for carbon dioxide (CO2) emissions from tropical deforestation in a future international climate treaty has received increasing attention recently. This attention has been prompted by proposals to this end and more intensified talks on possible commitments for developing countries beyond the United Nations Framework Convention on Climate Change Kyoto Protocol. We analyze four main scientific and political challenges associated with national targets for emissions from tropical deforestation: (1) reducing the uncertainties in emission inventories, (2) preserving the environmental integrity of the treaty, (3) promoting political acceptance and participation in the regime, and (4) providing economic incentives for reduced deforestation. We draw the following conclusions. (1) Although there are large uncertainties in carbon flux from deforestation, these are in the same range as for other emissions included in the current Kyoto protocol (i.e., non-CO2 GHGs), and they can be reduced. However, for forest degradation processes the uncertainties are larger. A large challenge lies in building competence and institutions for monitoring the full spectrum of land use changes in developing countries. (2 and 3) Setting targets for deforestation is difficult, and uncertainties in future emissions imply a risk of creating ‘tropical hot air’. However, there are proposals that may sufficiently deal with this, and these proposals may also have the advantage of making the targets more attractive, politically speaking. Moreover, we conclude that while a full carbon accounting system will likely be politically unacceptable for tropical countries, the current carbon accounting system should be broadened to include forest degradation in order to safeguard environmental integrity. (4) Doubts can be cast over the possible effect a climate regime alone will have on deforestation rates, though little thorough analysis of this issue has been made.
U. Martin PerssonEmail:
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2.
In view of the increasing interest in the development and dissemination of technologies for harnessing new and renewable sources of energy in India, there have also been some efforts towards their use in the domestic lighting sector. However, the cumulative number of Solar Photovoltaic (SPV) lighting systems such as SPV lanterns and solar home lighting systems in India is far below their theoretical potential despite government subsidy programmes. One of the major barriers is the high capital investment in these systems. The Clean Development Mechanism (CDM) provides industrialized countries with an incentive to invest in emission reduction projects in developing countries to achieve a reduction in CO2 emissions at lowest cost that also promotes sustainable development in the host country. SPV lanterns and solar home lighting systems could be of interest under the CDM because they directly displace greenhouse gas emissions while contributing to sustainable rural development. However, only two SPV projects have been submitted under the CDM so far. This study assesses the maximum theoretical as well as the realistically achievable CDM potential of SPV lanterns and solar home lighting systems in India. The SPV lantern project is financially viable at a certified emissions reductions (CER) price of 34 € whereas the solar home lighting project is financially viable at a CER price of 46 €. While the maximum mitigation volume is about 35 million tonne CO2 on an annual basis, an estimate of achievable CER levels is done using the past diffusion trends of SPV systems. We find that annual CER volumes could reach 0.8 to 2.4 million by 2012 and 5.6 to 13.6 million by 2020. This would require that the government sets the subsidy level for SPV lighting systems at a level that allows them to become viable with the CER revenue. From a macro-economic point of view this makes sense if the sustainability benefits are deemed sufficiently high to warrant promotion of this type of project.
Axel MichaelowaEmail:
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3.
An important aspect of present global energy scenarios is the assumption that the amount of biomass that can be grown on the available area is so limited that a scenario based on biomass as the major source of energy should be unrealistic. We have been investigating the question whether a Biomass Scenario may be realistic. We found that the global energy demand projected by the International Energy Agency in the Reference Scenario for the year 2030 could be provided sustainably and economically primarily from lignocellulosic biomass grown on areas which have been degraded by human activities in historical times. Moreover, other renewable energies will contribute to the energy mix. There would be no competition with increasing food demand for existing arable land. Afforestation of degraded areas and investment for energy and fuel usage of the biomass are not more expensive than investment in energy infrastructure necessary up to 2030 assumed in the fossil energy based Reference Scenario, probably much cheaper considering the additional advantages such as stopping the increase of and even slowly reducing the CO2 content of the atmosphere, soil, and water conservation and desertification control. Most importantly, investment for a Biomass Scenario would be actually sustainable, in contrast to investment in energy-supply infrastructure of the Reference Scenario. Methods of afforestation of degraded areas, cultivation, and energetic usage of lignocellulosic biomass are available but have to be further improved. Afforestation can be started immediately, has an impact in some few years, and may be realized in some decades. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Jürgen O. MetzgerEmail:
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4.
This paper addresses methodological issues in estimating carbon (C) sequestration potential, baseline determination, additionality and leakage in Khammam district, Andhra Pradesh, southern part of India. Technical potential for afforestation on cultivable wastelands, fallow, and marginal croplands was considered for Eucalyptus clonal plantations. Field studies for aboveground and belowground biomass, woody litter, and soil organic carbon for baseline and project scenarios were conducted to estimate the carbon sequestration potential. The baseline carbon stock was estimated to be 45.3 t C/ha, predominately in soils. The additional carbon sequestration potential under the project scenario for 30 years is estimated to be 12.8 t C/ha/year inclusive of harvest regimes and carbon emissions due to biomass burning and fertilizer application. Considering carbon storage in harvested wood, an additional 45% carbon benefit can be accounted. The project scenario has a higher benefit/cost ratio compared to the baseline scenario. The initial investment cost requirement, however, is high and lack of access to investment is a significant barrier for adoption of agroforestry in the district.
N. H. RavindranathEmail:
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5.
Climate equity is a crucial but difficult element in negotiations on a post-2012 climate regime. With respect to the trading of greenhouse gas emissions the equity aspect is considered in the Kyoto Protocol which demands that emissions trading should be supplemental to domestic abatement efforts. The question arises whether a linking of the European Union Emissions Trading Scheme (EU ETS) to non-EU emission trading schemes or the Clean Development Mechanism (CDM) could have an impact on principles of climate justice and thus potentially affect ongoing negotiations. In this study, we present the results of a three step analysis: In a first step, it estimates mid-term greenhouse gas emission entitlements for Annex B and Non-Annex B countries for the year 2020 which keep within reach a stabilization of the CO2 concentration at 450 ppmv in the long-term. In the second step, the resulting emission entitlements are used as an input to an economic partial-equilibrium model in order to assess the shift of abatement efforts under different scenarios of linking the EU ETS. In a third step, we analyze the outcome of the economic model with respect to the future trend of European per capita emissions under the current EU ETS relative to different scenarios of linking the EU ETS. The model results indicate that European per capita emissions have to be reduced to a considerably smaller extent if a linking of the EU ETS is accompanied by an optimal design of the National Allocation Plans and if low-cost CO2 permits became available via the CDM to a large extent.
B. BrounsEmail:
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6.
We investigate the role of domestic allowance allocation and global emissions constraints for the carbon-market impacts of linking the EU Emissions Trading Scheme (ETS) internationally. Employing a quantitative simulation model of the global carbon market, we find that the economic benefits from connecting the European ETS to emerging non-EU schemes strongly depend on the regional allowance allocation of the linking participants: In a world of moderate carbon constraints, an economically efficient regional allowance allocation induces a much stronger fall in total compliance costs than a sub-optimal (i.e. too high) domestic allocation of emissions permits. However, a more efficient (i.e. stricter) allocation shifts abatement efforts and compliance costs to energy-intensive industries which are covered by the domestic ETS. We further find that committing to ambitious global emissions reduction targets (compatible with stabilizing CO2 concentrations at 450 ppm) induces much stronger regional abatement efforts and substantially higher compliance costs for the abating regions. In such an ambitious climate policy regime, an efficient domestic allocation of allowances is even more important from an economic perspective: Here, linking emissions trading schemes diminishes the associated compliance costs on the largest scale.
J. OnigkeitEmail:
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7.
Fossil footprints are important in understanding Cretaceous avian diversity because they constitute evidence of paleodiversity and paleoecology that is not always apparent from skeletal remains. Early Cretaceous bird tracks have demonstrated the existence of wading birds in East Asia, but some pedal morphotypes, such as zygodactyly, common in modern and earlier Cenozoic birds (Neornithes) were unknown in the Cretaceous. We, herein, discuss the implications of a recently reported, Early Cretaceous (120–110 million years old) trackway of a large, zygodactyl bird from China that predates skeletal evidence of this foot morphology by at least 50 million years and includes the only known fossil zygodactyl footprints. The tracks demonstrate the existence of a Cretaceous bird not currently represented in the body fossil record that occupied a roadrunner (Geococcyx)-like niche, indicating a previously unknown degree of Cretaceous avian morphological and behavioral diversity that presaged later Cenozoic patterns. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Masaki MatsukawaEmail:
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8.
Almost two decades ago, Fleischmann and Pons reported excess enthalpy generation in the negatively polarized Pd/D-D2O system, which they attributed to nuclear reactions. In the months and years that followed, other manifestations of nuclear activities in this system were observed, viz. tritium and helium production and transmutation of elements. In this report, we present additional evidence, namely, the emission of highly energetic charged particles emitted from the Pd/D electrode when this system is placed in either an external electrostatic or magnetostatic field. The density of tracks registered by a CR-39 detector was found to be of a magnitude that provides undisputable evidence of their nuclear origin. The experiments were reproducible. A model based upon electron capture is proposed to explain the reaction products observed in the Pd/D-D2O system.
Pamela A. Mosier-BossEmail:
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9.
Setting a baseline for carbon stock changes in forest and land use sector mitigation projects is an essential step for assessing additionality of the project. There are two approaches for setting baselines namely, project-specific and regional baseline. This paper presents the methodology adopted for estimating the land available for mitigation, for developing a regional baseline, transaction cost involved and a comparison of project-specific and regional baseline. The study showed that it is possible to estimate the potential land and its suitability for afforestation and reforestation mitigation projects, using existing maps and data, in the dry zone of Karnataka, southern India. The study adopted a three-step approach for developing a regional baseline, namely: (i) identification of likely baseline options for land use, (ii) estimation of baseline rates of land-use change, and (iii) quantification of baseline carbon profile over time. The analysis showed that carbon stock estimates made for wastelands and fallow lands for project-specific as well as the regional baseline are comparable. The ratio of wasteland Carbon stocks of a project to regional baseline is 1.02, and that of fallow lands in the project to regional baseline is 0.97. The cost of conducting field studies for determination of regional baseline is about a quarter of the cost of developing a project-specific baseline on a per hectare basis. The study has shown the reliability, feasibility and cost-effectiveness of adopting regional baseline for forestry sector mitigation projects.
N. H. RavindranathEmail:
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10.
Approaches to semi-synthetic minimal cells: a review   总被引:1,自引:0,他引:1  
Following is a synthetic review on the minimal living cell, defined as an artificial or a semi-artificial cell having the minimal and sufficient number of components to be considered alive. We describe concepts and experiments based on these constructions, and we point out that an operational definition of minimal cell does not define a single species, but rather a broad family of interrelated cell-like structures. The relevance of these researches, considering that the minimal cell should also correspond to the early simple cell in the origin of life and early evolution, is also explained. In addition, we present detailed data in relation to minimal genome, with observations cited by several authors who agree on setting the theoretical full-fledged minimal genome to a figure between 200 and 300 genes. However, further theoretical assumptions may significantly reduce this number (i.e. by eliminating ribosomal proteins and by limiting DNA and RNA polymerases to only a few, less specific molecular species). Generally, the experimental approach to minimal cells consists in utilizing liposomes as cell models and in filling them with genes/enzymes corresponding to minimal cellular functions. To date, a few research groups have successfully induced the expression of single proteins, such as the green fluorescence protein, inside liposomes. Here, different approaches are described and compared. Present constructs are still rather far from the minimal cell, and experimental as well as theoretical difficulties opposing further reduction of complexity are discussed. While most of these minimal cell constructions may represent relatively poor imitations of a modern full-fledged cell, further studies will begin precisely from these constructs. In conclusion, we give a brief outline of the next possible steps on the road map to the minimal cell.
Pier Luigi Luisi (Corresponding author)Email:
Francesca FerriEmail:
Pasquale StanoEmail:
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11.
Recent paleogeographic scenarios postulate the isolation of continental Africa during the Late Cretaceous. The absence of abelisaurid theropods from Upper Cretaceous African strata was offered as support of hypothesized African isolation with the acknowledgement that the paucity of African abelisaurids may be mostly an issue of sampling. Here we report on a shed theropod tooth from the Upper Cretaceous (Maastrichtian, ∼70 Ma) Duwi Formation of Egypt. The tooth was referred to the Malagasy abelisaurid “Megalosauruscrenatissimus (=Majungasaurus crenatissimus) in 1921. A discriminant function analysis was run to test for morphological congruence between the Egyptian tooth and the dentitions of 24 theropod taxa. The analysis correctly classified 96.6% of the teeth in the sample and assigned the tooth to Majungasaurus. As current paleogeographic reconstructions posit Madagascar had attained its current position relative to Africa before the Late Cretaceous, it is unlikely that the Egyptian tooth actually pertains to Majungasaurus. Nevertheless, its classification as an abelisaurid supports its referral to the clade. This tooth thus constitutes defensible evidence of an abelisaurid from the post-Cenomanian Cretaceous of mainland Africa. Combined with recent discoveries of abelisaurids in Niger and Morocco, the result indicates that Abelisauridae was a diverse group in Africa during the Cretaceous, existing in multiple places for at least ∼25 Ma and weakens support for hypotheses of an isolated Africa during the Late Cretaceous.Electronic Supplementary Material  Supplementary material is available for this article at
Joshua B. Smith (Corresponding author)Email: Phone: +1-314-9357033Fax: +1-314-9357361
Matthew C. LamannaEmail:
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12.
There is a need to assess climate change mitigation opportunities in forest sector in India in the context of methodological issues such as additionality, permanence, leakage and baseline development in formulating forestry mitigation projects. A case study of forestry mitigation project in semi-arid community grazing lands and farmlands in Kolar district of Karnataka, was undertaken with regard to baseline and project scenario development, estimation of carbon stock change in the project, leakage estimation and assessment of cost-effectiveness of mitigation projects. Further, the transaction costs to develop project, and environmental and socio-economic impact of mitigation project was assessed. The study shows the feasibility of establishing baselines and project C-stock changes. Since the area has low or insignificant biomass, leakage is not an issue. The overall mitigation potential in Kolar for a total area of 14,000 ha under various mitigation options is 278,380 t C at a rate of 20 t C/ha for the period 2005–2035, which is approximately 0.67 t C/ha/year inclusive of harvest regimes under short rotation and long rotation mitigation options. The transaction cost for baseline establishment is less than a rupee/t C and for project scenario development is about Rs. 1.5–3.75/t C. The project enhances biodiversity and the socio-economic impact is also significant.
N. H. RavindranathEmail:
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13.
Institutions play an important role in the adaptive capacity of a system in responding to climate change. This review paper characterizes the status of the collective institutional response (government, industry, First Nation, community, civil society) to climate change in the forest sector of the Canadian province of Ontario, and highlights the presence and nature of inter-institutional networks as part of the response. Based on a synthesis of the commonalities in the public administration and policy literature on tackling wicked problems, and the resilience literature, inter-institutional networks, which foster exchange of different types of knowledge, are an important aspect of enhancing the adaptive capacity of social–ecological systems such as the forest sector. Based on a content analysis of publicly available documents and insights gained from representatives of government, community members and non-governmental organizations, mitigation and adaptations strategies are described. At the provincial level there have been some new innovations in inter-institutional networks, but expansion of the forest stakeholders involved in such networks would further enhance adaptive capacity. In particular, it is important to network with First Nations and other forest-dependent communities who have a heightened vulnerability to climate change. The presence of a collaborative capacity builder could foster the transfer, receipt and integration of knowledge across the networks, and ultimately build long-term collaborative problem-solving capacity in the Ontario forest sector.
H. Carolyn Peach BrownEmail:
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14.
If hydrogen (H2) is to significantly reduce greenhouse gas emissions and oil use, it needs to displace conventional transport fuels and be produced in ways that do not generate significant greenhouse gas emissions. This paper analyses alternative ways H2 can be produced, transported and used to achieve these goals. Several H2 scenarios are developed and compared to each other. In addition, other technology options to achieve these goals are analyzed. A full fuel cycle analysis is used to compare the energy use and carbon (C) emissions of different fuel and vehicle strategies. Fuel and vehicle costs are presented as well as cost-effectiveness estimates. Lowest hydrogen fuel costs are achieved using fossil fuels with carbon capture and storage. The fuel supply cost for a H2 fuel cell car would be close to those for an advanced gasoline car, once a large-scale supply system has been established. Biomass, wind, nuclear and solar sources are estimated to be considerably more expensive. However fuel cells cost much more than combustion engines. When vehicle costs are considered, climate policy incentives are probably insufficient to achieve a switch to H2. The carbon dioxide (CO2) mitigation cost would amount to several hundred US$ per ton of CO2. Energy security goals and the eventual need to stabilize greenhouse gas concentrations could be sufficient. Nonetheless, substantial development of related technologies, such as C capture and storage will be needed. Significant H2 use will also require substantial market intervention during a transition period when there are too few vehicles to motivate widely available H2 refueling.
Dolf GielenEmail:
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15.
Recent interest in sustainable forest management planning in the Yukon has coincided with growing public awareness of climate change, providing an opportunity to explore how forestry plans are incorporating climate change. In this paper, the Strategic Forest Management Plans for the Champagne and Aishihik First Nations Traditional Territory (CATT) and the Teslin Tlingit Traditional Territory (TTTT) are examined for evidence of adaptation to climate change. For each plan, management policies and practices that are also recognized as ways to adapt to climate change are identified to provide information on the incremental costs and benefits of additional adaptation efforts. A typology for classifying sustainable forest management plans according to how they address climate change is proposed and applied to the CATT and TTTT plans. This typology, which may be useful to any future retrospective assessments on how successful these or other sustainable forest management plans have been in addressing and managing the risks posed by climate change, consists of a matrix that categorizes plans into one of four types; (1) proactive-direct, (2) proactive-indirect, (3) reactive-direct, and (4) reactive-indirect. Neither of the plans available for the southern Yukon explicitly identifies climate change vulnerabilities and actions that will be taken to reduce those vulnerabilities and manage risks. However, both plans have incorporated some examples of ‘best management practices’ for sustainable forest management that are also consistent with appropriate climate adaptation responses. Even in a jurisdiction facing rapid ecological changes driven by climate change, where there is a relatively high level of awareness of climate change and its implications, forestry planning processes have yet to grapple directly with the risks that climate change may pose to the ability of forest managers to achieve the stated goals and objectives of sustainable forest management plans.
J. L. InnesEmail:
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16.
Over the past decade “bicellar” lipid mixtures composed of the long-chain dimyristoyl phosphatidylcholine (DMPC) and the short-chain dihexanoyl PC (DHPC) molecules have emerged as a powerful medium for studying membrane associated, biologically relevant macromolecules and assemblies. Depending on temperature, lipid concentration and composition these lipid mixtures can assume a variety of morphologies, some of them alignable in the presence of a magnetic field. This article will examine the biophysical studies that have elucidated the various morphologies assumed by these lipid mixtures, and their use in the biochemical studies of biomolecules.
John KatsarasEmail:
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17.
Kirschbaum (Mitig Adapt Strat Glob Change 11:1151–1164, 2006) explores the climatic impact over time of temporarily sequestering carbon from the atmosphere. He concludes that temporary storage of carbon in the terrestrial biosphere “achieves effectively no climate-change mitigation”. His strongly worded statement begs for a response. This paper argues that Kirschbaum’s conclusion is an artifact of the specific perspective of his analysis and his choice of a definition for climate-change impact. Even temporary sinks put us on a lower path for climate change, a path that will not otherwise be accessible. For carbon sinks in the terrestrial biosphere, we argue that sooner is better and longer is better, but even known temporary sinks have value.
Gregg Marland (Corresponding author)Email:
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18.
Molecular topology is an application of graph theory and statistics in fields like chemistry, biology, and pharmacology, in which the molecular structure matters. Its scope is the topological characterization of molecules by means of numerical invariants, called topological indices, which are the main ingredients of the molecular topological models. These are statistical models that are instrumental in the discovery of new applications of naturally occurring molecules, as well as in the design of synthetic molecules with specific chemical, biological, or pharmacological properties. In this review, we focus on pharmacology, which is a novel field of application of molecular topology. Besides summarizing some recent developments, we also seek to bring closer this interesting biomedical application of mathematics to an interdisciplinary readership.
Vincent M. VillarEmail:
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19.
India occupies 2.4% of the world’s geographical area with a large percentage of its land under agriculture. About 228 Million hectares (Mha) of its geographical area (nearly 69%) fall within the dryland (arid, semi-arid and dry sub-humid) region. Of the total cultivated area of 142 Mha, major part of agriculture in the country is rainfed, extending to over 97 Mha and constituting nearly 68% of the net cultivated area, therefore making the agricultural sector vulnerable and exposed to the vagaries of weather conditions. Climate change adds to this dimension of stress. A strong need is felt for targeting programmes in these areas that address issues related to employing suitable soil and water conservation measures. In this context this paper seeks to examine the case for watershed development as an adaptive strategy. An examination of the possibility of fortifying the existing programme with a view to adapting to expected changes in climate in future is undertaken. Also, the possibility of watershed development integrating into a suitable mitigation strategy for the country is assessed.
Preety M. BhandariEmail:
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20.
This paper studies the effects of adaptation and mitigation on the impacts of sea level rise. Without adaptation, the impact of sea level rise would be substantial, almost wiping out entire countries by 2100, although the globally aggregate effect is much smaller. Adaptation would reduce potential impacts by a factor 10–100. Adaptation would come at a minor cost compared to the damage avoided. As adaptation depends on socio-economic status, the rank order of most vulnerable countries is different than the rank order of most exposed countries. Because the momentum of sea level rise is so large, mitigation can reduce impacts only to a limited extent. Stabilising carbon dioxide concentrations at 550 ppm would cut impacts in 2100 by about 10%. However, the costs of emission reduction lower the avoided impacts by up to 25% (average 10%). This is partly due to the reduced availability of resources for adaptation, and partly due to the increased sensitivity to wetland loss by adaptation.
Richard S. J. TolEmail:
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