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1.
Biofuels are emerging as a prominent renewable and sustainable energy sources in developed countries. In this sense, this paper presents a case study in which a biorefinery has to be sited in Northern Spain. Thus, the strategic decision of locating such a facility is deeply investigated through strategic policy evaluation. Then, tactical decisions ranging from purchasing and transportation policies to storage protocols are carried out. Only local and limited biomass can be harvested for supplying the biorefinery through a heterogeneous vehicle fleet. Moreover two different and mutually exclusive storage strategies are evaluated: direct supply from crops to biorefinery and using intermediate-collectors. Additionally, crop exploitation factors and biorefinery sizes are used to generate several scenarios in which the strategic decision of location as well as all the tactic decisions are made. Some mixed integer linear programming models are proposed to figure out all relevant decision problems.The results suggest that the Northwest study area as the best option to locate the biorefinery and recommend the intermediate-collector storage strategy. Moreover, the key information about critical biomass, crops and times are also provided.  相似文献   
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Humanity's role in shaping patterns and processes in the terrestrial biosphere is large and growing. Most of the earth's fertile land is used more or less intensively by humans for resource extraction, production, transport, consumption and waste deposition or as living space. Biomass production on cropland, grazing areas and in managed forests dominates area requirements, but other processes such as soil degradation, human-induced fires and expansion of settlements and infrastructure play an increasingly important role as well. The growing human domination of terrestrial ecosystems contributes to biodiversity loss as well as to a reduced capability of ecosystems to deliver vital services such as buffering capacity, soil conservation or self-regulation. This special section is devoted to the presentation of recent research into the patterns, determinants and implications of the human appropriation of net primary production (HANPP), an integrated socio-ecological indicator of land use intensity. By measuring the combined effect of land conversion and biomass harvest on the availability of trophic energy (biomass) in ecosystems, HANPP explicitly links natural with socioeconomic processes and allows for integrated analyses of land systems. This introductory article explains the rationale that links current HANPP research to Ecological Economics and discusses issues of definition and methods shared by all articles included in the special section. Finally, it gives an overview of the individual papers, provides some general conclusions and presents an outlook for future research: a better understanding of long-term trajectories of HANPP, of the significance of trade patterns as well as of the future role of bioenergy are highlighted as important issues to be addressed in the coming years.  相似文献   
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The establishment of deep-rooted perennial species and their processing for biomass-based products such as renewable energy can have benefits for both local and global scale environmental objectives. In this study, we assess the potential economic viability of biomass production in the South Australian River Murray Corridor and quantify the resultant benefits for local and global scale environmental objectives. We model the spatial distribution of economically viable biomass production in a Geographic Information System and quantify the model sensitivity and uncertainty using Monte Carlo analysis. The total potentially viable area for biomass production under the Most Likely Scenario is 360,728 ha (57.7% of the dryland agricultural area), producing over 3 million tonnes of green biomass per annum, with a total Net Present Value over 100 years of A$ 88 million. The salinity in the River Murray could be reduced by 2.65 EC (μS/cm) over a 100-year timeframe, and over 96,000 ha of land with high wind erosion potential could be stabilised over a much shorter period. With sufficient generating capacity, our Most Likely Scenario suggests that economically viable biomass production could reduce carbon emissions by over 1.7 million tonnes per annum through the production of renewable energy and a reduced reliance on coal-based electricity generation. Our analyses suggest that biomass production is a potentially viable alternative agricultural system that can have substantial local scale environmental benefits with complimentary global scale benefits for climate change mitigation.  相似文献   
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Valuing climate protection through willingness to pay for biomass ethanol   总被引:3,自引:0,他引:3  
This study uses a multi-part, split-sample contingent valuation method (CVM) and fair share (FS) survey to better understand the public's valuation of mitigating global climate change through its willingness to pay for biomass or “cellulosic” ethanol. In addition to a basic CVM question, a related scenario was developed that asked half of the survey respondents to state their fair share cost to lessen a potential food shortage in the next decade, also through the expanded use of cellulosic ethanol. Three alternative biomass feedstocks were assessed: farming residues, forestry residues and paper mill wastes, and municipal solid wastes. Overall a slightly larger proportion of respondents were WTP extra for cellulosic ethanol in the basic CVM scenario than in the FS scenario, though no significant differences were found in the WTP for the different feedstocks. Bid curve lognormal regression results for the two models were similar, supporting the idea that asking a FS rather than a conventional WTP question may be justifiable in some circumstances, such as in cases of a national emergency.  相似文献   
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This paper presents an empirical analysis of the human appropriation of aboveground net primary production (aHANPP) in Hungary in the years 1961-2005. In this period aboveground HANPP dropped from 67% to 49% of the potential vegetation's NPP. The trajectory was not smooth, but aboveground HANPP fluctuated with changes in factors affecting agricultural production conditions. Both aboveground net primary production (aNPP) of the prevailing vegetation and harvested aNPP increased during the socialist regime, dropped when the system collapsed and has shown considerable fluctuations since. We discuss the development of aboveground HANPP and the Hungarian land use system in the context of socioeconomic changes during three distinct phases: (1) industrialisation of agriculture (1961-1989), (2) regime collapse (1989-1993) and (3) restructuring of a new economy (1993-2005). Within these periods, different driving factors influenced aboveground HANPP and its constituents. In the phase of industrialisation, mechanisation and agrochemical inputs reduced aHANPP while harvested amounts of biomass increased progressively. In the second phase, political and economic circumstances devastated production conditions resulting in a decline of productivity of actual vegetation and a temporary rise in aboveground HANPP. During the last twelve years, industrialisation patterns of agricultural production recovered. The restructuring of inefficient agricultural production systems raised harvest at moderate levels of agricultural inputs, while climatic conditions intimidated high yield and harvest security. The paper discusses the effect of different economic and political regimes and of major socioeconomic restructuring on the development of the land use system, biomass production and aboveground HANPP.  相似文献   
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随着农村经济发展和农民收入的逐年提高,我国农村居民能源消费在总量上已得到基本满足,但结构亟待优化。农村能源结构调整的最终目标是“去煤化”,即通过发展现代生物质能、太阳能、风能等新能源来替代化石能源。实现这一目标,应根据“因地制宜、多能互补、综合利用、讲求效益”的方针逐步推进。根据河北省目前的实际情况,应把生物质能源的开发利用放在首要地位,其次要加强太阳能的推广和利用,同时优质低硫煤推广工作也应并行展开。  相似文献   
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Harvesting of prey biomass is analyzed in an integrated ecological-economic system whose submodels, a predator–prey ecosystem and a simple economy, are microfounded dynamic general equilibrium models. These submodels are interdependent because the ecosystem responds to harvesting—through the reactions of optimizing individual organisms—by changing the provision of public ecosystem services to consumers. General analytical results are derived regarding the impact of harvesting policies on short-run equilibria of both submodels, on population dynamics, and on stationary states of the integrated model. A key insight is that prey biomass carries a positive ecosystem price which needs to be added as a tax mark-up to the economic price of harvested biomass to attain allocative efficiency. Further information on the dynamics is gained by resorting to numerical analysis of the policy regimes of zero harvesting, laissez-faire harvesting and efficient harvesting.
It “... is a matter of weighing costs and benefits of taking action, whether the action is the “inert” one of leaving resources alone in order to conserve them, or whether it involves exploiting a resource ... for so-called material ends”. Pearce (1976, p. 320)
Helpful comments from an anonymous referee are gratefully acknowledged. Remaining errors are the authors’ sole responsibility.  相似文献   
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小叶章分株高度的季节动态:典型草甸和沼泽化草甸在8月末均达到最大值,沼泽在7月末达到最大值,而后缓慢下降。小叶章种群茎构件和叶构件生物量的季节动态在三个生境中均表现出较一致的变化规律,均自5月末开始,各生境的数量性状逐渐增加,至7月末达到最大值,而后逐渐下降,呈抛物线型。三个生境小叶章分株F/C值均具有相似季节变化趋势。其极大值均出现在7月末,但三个生境之间亦有明显差异, F/C值的整体水平表现为沼泽>沼泽化草甸>典型草甸,其极大值、极小值亦反映出此规律。  相似文献   
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