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1.
This study compares energy savings and greenhouse gas (GHG) emission reductions of biobased polymers with those of bioenergy on a per unit of agricultural land-use basis by extending existing life-cycle assessment (LCA) studies. In view of policy goals to increase the energy supply from biomass and current efforts to produce biobased polymers in bulk, the amount of available land for the production of nonfood crops could become a limitation. Hence, given the prominence of energy and greenhouse issues in current environmental policy, it is desirable to include land demand in the comparison of different biomass options. Over the past few years, numerous LCA studies have been prepared for different types of bio-based polymers, but only a few of these studies address the aspect of land use. This comparison shows that referring energy savings and GHG emission reduction of biobased polymers to a unit of agricultural land, instead of to a unit of polymer produced, leads to a different ranking of options. If land use is chosen as the basis of comparison, natural fiber composites and thermoplastic starch score better than bioenergy production from energy crops, whereas polylactides score comparably well and polyhydroxyalkaonates score worse. Additionally, including the use of agricultural residues for energy purposes improves the environmental performance of bio-based polymers significantly. Moreover, it is very likely that higher production efficiencies will be achieved for biobased polymers in the medium term. Biobased polymers thus offer interesting opportunities to reduce the utilization of nonrenewable energy and to contribute to GHG mitigation in view of potentially scarce land resources.  相似文献   

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Based on regional stakeholder preferences and planning guidelines as allocation criteria for SRC, this study aims at providing a transparent approach to evaluate multiple environmental effects and the regional significance of SRC systems. Using the example of two poplar SRC-systems (4-year rotation, 9-year rotation) the potential effects on ground water supply, wind erosion, and biodiversity aspects are evaluated in comparison to arable land for two selected municipalities in the district of Uelzen, Germany. Building on fuzzy membership functions and simple fuzzy-logic rules, the qualitative multi-criteria assessment is transparent and easily to adapt. This approach is transferable to other regions and spatial levels, since it derives from commonly available data and scientific evidence. Results show that implementation of SRC could provide multiple beneficial environmental effects, especially in areas with low landscape heterogeneity. The tools provided allow for a multi-criteria evaluation of environmental effects, and reveal the sensitivity to distinct allocation patterns. Physiographical conditions of the study area implicate a preference for mini-SRC systems. This is supported by smaller decline of annual deep percolation water compared to maxi-SRC. On average, decline in groundwater recharge of mini-SRC (92mm a−1) is comparable to irrigated arable land (80mm a−1), which is common practice in the study area. Currently, the utilization of beneficial environmental SRC effects is quite limited, since only 3 % of arable land is suitable for SRC implementation regarding farmers’ preferences for SRC allocation. Allocation preferences could however change substantially with increasing incentives for SRC, e.g., due to regional bioenergy schemes or “Greening” initiatives within the European Common Agricultural Policy, which is to be reformed by 2013.  相似文献   

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For hundreds of years, sugarcane has been a main source of sugar, used as a sweetener, and alcohol, fermented from the plant juice. The high cost of petroleum towards the end of the twentieth century stimulated the development of new fermentation technologies for producing economically viable bioethanol from sugarcane as an alternative to importing petroleum. More recently, awareness of the effects of greenhouse gas emissions due to the global climate changes propelled bioethanol as a viable renewable fuel. Consequently, sugarcane gained importance as a bioenergy feedstock. However, the lack of knowledge about sugarcane physiology, notably on aspects of photosynthesis and source–sink relationship, has slowed the advance of this expanding bioenergy-producing system. Besides the changes in source–sink relationship, another option to increase bioethanol production even more would be to use a greater fraction of the total biomass of plants, i.e., not only the soluble sugars but also the sugars present in the cell wall fractions. Here, we review the history of sugarcane as a bioenergy crop and discuss some of the relevant routes that could be adopted in the near future to make sugarcane an even better feedstock for producing biofuels.  相似文献   

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This protocol describes a fluorescence microscope-based screening of Arabidopsis seedlings and describes how to map recessive mutations that alter the subcellular distribution of a specific tagged fluorescent marker in the secretory pathway. Arabidopsis is a powerful biological model for genetic studies because of its genome size, generation time, and conservation of molecular mechanisms among kingdoms. The array genotyping as an approach to map the mutation in alternative to the traditional method based on molecular markers is advantageous because it is relatively faster and may allow the mapping of several mutants in a really short time frame. This method allows the identification of proteins that can influence the integrity of any organelle in plants. Here, as an example, we propose a screen to map genes important for the integrity of the endoplasmic reticulum (ER). Our approach, however, can be easily extended to other plant cell organelles (for example see1,2), and thus represents an important step toward understanding the molecular basis governing other subcellular structures.  相似文献   

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Noncyclic fluorine-substituted and cyclic analogs of glutamic acid were tested for their ability to inhibit glutamate uptake in isolated bovine presynaptic vesicles, in order to assess the specific structural requirements of the glutamate translocation system in the vesicle membrane. Cyclic analogs that permitted close interaction between the positive and negative charges of the glutamate molecule were effective inhibitors; maximum inhibitory potency was observed with L-trans-1-aminocyclopentane-1,3-dicarboxylic acid (l-t-ACPD), while d-t-ACPD was less active. Analogs with a larger or smaller ring (as in trans-1-aminocyclohexane-1,3-dicarboxylic acid or trans-1-aminocyclobutane-1,3-dicarboxylic acid) were also inhibitory, but somewhat less so. trans-ACPD was also taken up by the vesicles with a time course and ATP dependence similar to uptake of glutamate, and this uptake was inhibited by glutamate. The K m value for t-ACPD uptake was similar to its K i for inhibition of glutamate uptake, while its rate of uptake was lower than that of glutamate. Fluorine-substituted noncyclic analogs with substitutions at the 4-carbon were less effective than glutamic acid itself, although 4,4-difluoroglutamic acid was equal in activity to the unsubstituted compound. Inhibition by these derivatives appeared to be competitive in nature, and they probably were also transported by the vesicle uptake system. Special issue article in honor of Dr. Frode Fonnum.  相似文献   

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With high productivity and stress tolerance, numerous grass genera of the Andropogoneae have emerged as candidates for bioenergy production. To optimize these candidates, research examining the genetic architecture of yield, carbon partitioning, and composition is required to advance breeding objectives. Significant progress has been made developing genetic and genomic resources for Andropogoneae, and advances in comparative and computational genomics have enabled research examining the genetic basis of photosynthesis, carbon partitioning, composition, and sink strength. To provide a pivotal resource aimed at developing a comparative understanding of key bioenergy traits in the Andropogoneae, we have established and characterized an association panel of 390 racially, geographically, and phenotypically diverse Sorghum bicolor accessions with 232,303 genetic markers. Sorghum bicolor was selected because of its genomic simplicity, phenotypic diversity, significant genomic tools, and its agricultural productivity and resilience. We have demonstrated the value of sorghum as a functional model for candidate gene discovery for bioenergy Andropogoneae by performing genome-wide association analysis for two contrasting phenotypes representing key components of structural and non-structural carbohydrates. We identified potential genes, including a cellulase enzyme and a vacuolar transporter, associated with increased non-structural carbohydrates that could lead to bioenergy sorghum improvement. Although our analysis identified genes with potentially clear functions, other candidates did not have assigned functions, suggesting novel molecular mechanisms for carbon partitioning traits. These results, combined with our characterization of phenotypic and genetic diversity and the public accessibility of each accession and genomic data, demonstrate the value of this resource and provide a foundation for future improvement of sorghum and related grasses for bioenergy production.  相似文献   

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The biomass production potential at temperate latitudes (56°N), and the quality of the biomass for energy production (anaerobic digestion to methane and direct combustion) were investigated for the green macroalgae, Ulva lactuca. The algae were cultivated in a land based facility demonstrating a production potential of 45 T (TS) ha−1 y−1. Biogas production from fresh and macerated U. lactuca yielded up to 271 ml CH4 g−1 VS, which is in the range of the methane production from cattle manure and land based energy crops, such as grass-clover. Drying of the biomass resulted in a 5-9-fold increase in weight specific methane production compared to wet biomass. Ash and alkali contents are the main challenges in the use of U. lactuca for direct combustion. Application of a bio-refinery concept could increase the economical value of the U. lactuca biomass as well as improve its suitability for production of bioenergy.  相似文献   

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Short rotation coppice (SRC) willow is an emerging cropping system in focus for production of biomass for energy. To increase production, the willow is commonly fertilized, but studies have shown differing effects of fertilization on biomass production, ranging from almost no response to considerable positive effects. Focus has also been on replacing mineral fertilizer with organic waste products, such as manure and sludge. However, the effect on biomass production and environmental impact of various dosage and types of fertilizer is not well described. Therefore we studied the environmental impacts of different doses of mineral fertilizer, manure and sewage sludge in a commercially grown SRC willow stand. We examined macro nutrient and heavy metal leaching rates and calculated element balances to evaluate the environmental impact. Growth responses were reported in a former paper (Sevel et al. “Fertilization of SRC Willow, I: Biomass Production Response” Bioenergy Research, 2013). Nitrogen leaching was generally low, between 1 and 7 kg N ha?1 year?1 when doses of up to 120 kg N ha?1 year?1 were applied. Higher doses of 240 and 360 kg N ha?1 as single applications caused leaching of 66 and 99 kg N ha?1 year?1, respectively, indicating N saturation of the system. Previous intensive farming including high doses of fertilizer may be responsible for a high soil N status and the high N leaching rates. However, moderate fertilization input could not compensate P and K exports with the biomass harvest. No elevated leaching of heavy metals was observed for any fertilization treatments and more cadmium than applied with the fertilizer was removed with the biomass from the system.  相似文献   

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For lignocellulosic bioenergy to become a viable alternative to traditional energy production methods, rapid increases in conversion efficiency and biomass yield must be achieved. Increased productivity in bioenergy production can be achieved through concomitant gains in processing efficiency as well as genetic improvement of feedstock that have the potential for bioenergy production at an industrial scale. The purpose of this review is to explore the genetic and genomic resource landscape for the improvement of a specific bioenergy feedstock group, the C4 bioenergy grasses. First, bioenergy grass feedstock traits relevant to biochemical conversion are examined. Then we outline genetic resources available bioenergy grasses for mapping bioenergy traits to DNA markers and genes. This is followed by a discussion of genomic tools and how they can be applied to understanding bioenergy grass feedstock trait genetic mechanisms leading to further improvement opportunities.  相似文献   

12.
The sustainability assessment of public sector organizations including municipalities, with a focus on the integration of health, safety, and environmental (HSE) issues in the context of sustainability performance indicators, has almost remained underexplored. Moreover, since a large number of the activities of megacities’ municipalities have directly to do with HSE issues, there seems to be a substantial gap in the study of megacities and corresponding local public administrations. The present study is aimed at developing a performance evaluation tool, supported by indicators, to monitor the HSE aspects of sustainable development in the municipalities of megacities. To put the proposed tool into practice, a set of performance evaluation indicators is proposed to be adopted in Iranian municipalities, integrated in the megacity of Tehran. The selection process was conducted by employing Delphi technique. In doing so, a 2-round questionnaire was responded by qualified experts to select the most robust indicators of HSE performance and evaluate the priority of each indicator. A total of 80 indicators were generated and grouped into 13 categories, 29 sub-categories, and 7 themes- (Health (H), Safety (S), Environment (E), Health-Safety (HS), Health-Environment (HE), Safety-Environment (SE), and Health, Safety and Environment (HSE)). Findings indicate that amongst the overall average score of the 13 categories, “Fire and emergency response” is the most important category, closely followed by “Waste”, “Transportation”, and “Natural systems” categories. Moreover, among the 7 proposed themes, the integrated “HSE theme”, nearly followed by “safety theme”, plays the most significant role in enhancing the HSE performance of sustainability in Tehran municipalities. It is concluded that in the HSE context of the megacities municipalities under scrutiny, social aspects of sustainability gain more attention in comparison with the environmental ones. Furthermore, in municipalities of megacities, the indicators related to health and safety could be considered as ‘key indicators’ and should be thus classified into independent categories so that their roles can be highlighted in the management and assessment of municipal sustainable development.  相似文献   

13.
Health care organization foundations and other fund-raising departments often function at an arm’s length from the system at large. As such, operations related to their mandate to raise funds and market the organization do not receive the same level of ethical scrutiny brought to bear on other arms within the organization. An area that could benefit from a more focused ethics lens is the use of language and rhetoric employed in order to raise funds and market the organization. Such departments and divisions often utilize overblown promises of miracles and extraordinary advances to convince donors to contribute and to persuade the general public. The result can be a heightened sense of expectation on the part of patients, their families, and the general public as to what can realistically be achieved by the health care system, leading to disappointment and conflict when these expectations are not or cannot be met. This article suggests that such advertising and marketing be subject to the same advertising standards as other businesses.  相似文献   

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Biomass energy crops are prompting major land-use changes in agricultural and marginal land in an effort to reduce dependency on fossil fuels. Miscanthus × giganteus, a perennial giant grass, is one of the main such crops in Europe but few studies exist of its interaction with farmland wildlife, particularly mammals. Understanding ecological impacts of bioenergy planting schemes is vital for mitigating potential negative effects on already declining farmland biodiversity and for maximising any benefits from these low-management, structurally diverse crops. We assessed in a mixed farming area in the UK the impact of Miscanthus crops on the brown hare (Lepus europaeus), a widespread but declining farmland species of conservation concern. We intensively radio-tracked hares in Miscanthus blocks of contrasting size and analysed hare diet for evidence of the consumption of Miscanthus. Home ranges differed starkly averaging 10.5 versus 49.6 ha in the small and the large Miscanthus blocks, respectively. Despite entirely avoiding the crop as food, hares appeared able to exist and even thrive in areas planted with Miscanthus though their populations may be significantly limited by reduced food availability and increased energy use where dense Miscanthus is planted over a wide area. As a component of a mixed farming landscape, Miscanthus may provide biodiversity benefits by increasing spatial heterogeneity and refuge areas for declining farmland species like brown hares but any effect is likely to be strongly scale-dependant.  相似文献   

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The prominent attributes of foxtail millet (Setaria italica L.) including its small genome size, short life cycle, inbreeding nature, and phylogenetic proximity to various biofuel crops have made this crop an excellent model system to investigate various aspects of architectural, evolutionary and physiological significances in Panicoid bioenergy grasses. After release of its whole genome sequence, large-scale genomic resources in terms of molecular markers were generated for the improvement of both foxtail millet and its related species. Hence it is now essential to congregate, curate and make available these genomic resources for the benefit of researchers and breeders working towards crop improvement. In view of this, we have constructed the Foxtail millet Marker Database (FmMDb; http://www.nipgr.res.in/foxtail.html), a comprehensive online database for information retrieval, visualization and management of large-scale marker datasets with unrestricted public access. FmMDb is the first database which provides complete marker information to the plant science community attempting to produce elite cultivars of millet and bioenergy grass species, thus addressing global food insecurity.  相似文献   

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Because many natural resources are limited, sustainability becomes an important concept in maintaining the human population, health, and environment. Mushrooms are a group of saprotrophic fungi. Mushroom cultivation is a direct utilization of their ecological role in the bioconversion of solid wastes generated from industry and agriculture into edible biomass, which could also be regarded as a functional food or as a source of drugs and pharmaceuticals. To make the mushroom cultivation an environmentally friendly industry, the basic biology of mushrooms and the cultivation technology must be researched and developed. This is very true for Lentinula edodes, Volvariella volvacea, and Ganoderma lucidum, which are commonly consumed in Asian communities but are now gaining popularity worldwide. Besides the conventional method, strain improvement can also be exploited by protoplast fusion and transformation. Biodiversity is the key contribution to the genetic resource for breeding programs to fulfill different consumer demands. The conservation of these mushrooms becomes essential and is in immediate need not only because of the massive habitat loss as a result of human inhabitation and deforestation, but also because of the introduced competition by a cultivar with the wild germ plasm. Spent mushroom compost, a bulky solid waste generated from the mushroom industry, however, can be exploited as a soil fertilizer and as a prospective bioremediating agent.  相似文献   

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Sarkar A  Patil S  Hugar LB  vanLoon G 《EcoHealth》2011,8(4):418-431
In order to support agribusiness and to attain food security for ever-increasing populations, most countries in the world have embraced modern agricultural technologies. Ecological consequences of the technocentric approaches, and their sustainability and impacts on human health have, however, not received adequate attention particularly in developing countries. India is one country that has undergone a rapid transformation in the field of agriculture by adopting strategies of the Green Revolution. This article provides a comparative analysis of the effects of older and newer paradigms of agricultural practices on ecosystem and human health within the larger context of sustainability. The study was conducted in three closely situated areas where different agricultural practices were followed: (a) the head-end of a modern canal-irrigated area, (b) an adjacent dryland, and (c) an area (the ancient area) that has been provided with irrigation for some 800 years. Data were collected by in-depth interviews of individual farmers, focus-group discussions, participatory observations, and from secondary sources. The dryland, receiving limited rainfall, continues to practice diverse cropping centered to a large extent on traditional coarse cereals and uses only small amounts of chemical inputs. On the other hand, modern agriculture in the head-end emphasizes continuous cropping of rice supported by extensive and indiscriminate use of agrochemicals. Market forces have, to a significant degree, influenced the ancient area to abandon much of its early practices of organic farming and to take up aspects of modern agricultural practice. Rice cultivation in the irrigated parts has changed the local landscape and vegetation and has augmented the mosquito population, which is a potential vector for malaria, Japanese encephalitis and other diseases. Nevertheless, despite these problems, perceptions of adverse environmental effects are lowest in the heavily irrigated area.  相似文献   

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In recent years, comparative observations of primate anatomies have been extended using measurements and computer analyses: morphometrics. A question then follows. Can we extend field observations of animal lifestyles using measurement and computer analysis, using, in other words, a new «niche metrics», for comparison with the morphometrics of animal anatomies? This has been attempted (Oxnard, Crompton & Lieberman, 1990) by «measuring» 17 lifestyle variables (on locomotion, environment and diet) for 28 prosimian primate species. These data have been analysed by multivariate statistical methods entirely similar to those used in morphometrics. The results define groups of prosimian species that seem not to be related directly with taxonomy and evolution, but with functional adaptation to lifestyle. Comparisons between the morphometric and niche metric results reveal a degree of similarity of species grouping in each that is apparently related to adaptation and remarkably detailed. But further study of both the morphometric and niche metric results suggests that questions pertaining to evolution may also be asked. Thus, both morphometric investigations seeking clusterings of anatomical variables and niche metric studies seeking clustering of higher taxonomic groups of species produce results that seem to be of developmental and phylogenetic rather than directly adaptive import. Through the combination of these two approaches, it may eventually be possible to partition both evolutionary and adaptive components, even though, of course, there must always be overlap between them.  相似文献   

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