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91.
Disputes over agriculture and foodproduction have occurred against a background ofdisputed authority with regard to governments,experts, and single issue pressure groups. Consumershave intervened in quite significant ways with manyaltering their buying patterns. The conventionalassessment of consumer ``preferences' throughaggregated purchases fails to reflect the ethicalnature of significant numbers of purchase decisions.Nevertheless, consumers seem to offer a wider basis onwhich to consider ethical issues. The author proposesthat a valuable inclusion of consumer opinion in thedebates would require a move away from neo-classicaleconomics and the selective inclusion of consumeropinion to unravel the complexity of (aggregated)consumer behavior. It is argued that Hirschman'sframework of ``exit, voice, and loyalty' is a moreappropriate tool for the understanding of ethics infood consumption.  相似文献   
92.
The reduction of CO2 emissions constitutes one of the largest challenges of the current era. Sustainable transportation, and especially cycling, can contribute to the mitigation of CO2 emissions since cycling possesses an intrinsic zero‐emission value. Few studies have been conducted that appraise the CO2 reduction potential of cycling. Opportunity costs enable the estimation of avoided CO2 emissions resulting from bicycle trips. The methodology developed in this research allows the attribution of a climate value to cycling by substituting bicycle trips with their most likely alternative transportation modes and calculating the resulting additional CO2 emissions. The methodology uses data on the current modal shares of cycling mobility, the competition of cycling with other transportation modes, and CO2 emission factors to calculate the climate value of cycling. When it is assumed that the avoided CO2 emissions of cycling mobility could be traded on financial carbon markets, the climate value of cycling represents a monetary value. Application of the methodology to the case of Bogotá, Colombia — a city with a current bicycle modal share of 3.3% on a total of 10 million daily trips — results in a climate value of cycling of 55,115 tons of CO2 per year, corresponding to an economic value of between 1 and 7 million US dollars when traded on the carbon market.  相似文献   
93.
Water demand management, or making better use of the water we have — as opposed to augmenting supply — is increasingly proposed as a way of mitigating water-scarcity problems. Moving water away from agriculture to uses with higher economic value is one of the main measures widely seen as desirable. Sectoral "allocation stress" is seen as resulting from the disproportionate share, and inefficient use of water in the agricultural sector. This apparent misallocation is often attributed to the failure of government to allocate water rationally.
This paper revisits this commonly-accepted wisdom and examines the nature of urban water scarcity, showing the importance of economic and political factors, shaped by incentives to decision-makers, and sometimes compounded by climatic conditions. It shows that cities' growth is not generally constrained by competition with agriculture. In general, rather than using a narrow financial criterion, cities select options that go along the "path of least resistance," whereby economic, social and political costs are considered in conjunction. The question of allocation stress is thus reframed into an inquiry of how transfers effectively occur and can be made more effective.  相似文献   
94.
We investigate the efficiency and environmental impacts of electricity market restructuring by examining changes in fuel efficiency, cost of coal purchases, and utilization among coal-fired power plants based on a panel data set from 1991 to 2005. Our study focuses exclusively on coal-fired power plants and uses panel data covering several years after implementation of restructuring. The estimation compares how investor-owned (IOs) plants in states with restructuring changed their behavior relative to IOs in states without. Our analysis finds that restructuring led to: (1) a 1.4 percent improvement in fuel efficiency, (2) an 8 percent decrease in unit cost of heat input, and (3) a lower capacity factor even after adjusting for cross-plant generation re-allocation due to cost reductions. The estimates imply that restructuring has led to nearly 15 percent savings in operating expenses and up to 7.5 percent emissions reduction among these plants.  相似文献   
95.
Through the lens of institutional economics, this paper reviews the reform and development experience in China's rural forest sector and discusses lessons that can be learned by China and other countries. We find that the impacts of the reforms, characterized by changes in forest tenures and market settings, hinge on how they are implemented. If farmers are granted not only land use rights but also liberalized market access, as shown in the northern farm region and the production of non-timber forest products, the incentive structure will be improved, and thus forest production will grow and producers and consumers will benefit. If the reforms are implemented in such a way as to cause market control and distortions, as witnessed in the southern traditional timber production region, the incentive structure will improve little. The chances for production increase will thus be diminished, making it difficult for producers and consumers to enhance their welfare. While tenure arrangements have evolved across the country in the 1990s, timber production in the south remains subject to allowable quota, cutting permit, government procurement, and heavy taxation. We wonder what the land use and tree ownership rights mean without the right to access market freely and fairly, and how practical it is to substitute government efforts for private initiatives in a successful forestry program. The time has come for Chinese policymakers to address these problems.  相似文献   
96.
Bushmeat markets exist in many countries in West and Central Africa, and data on species sold can be used to detect patterns of wildlife trade in a region. We surveyed 89 markets within the Cross–Sanaga rivers region, West Africa. In each market, we counted the number of carcasses of each taxon sold. During a 6‐month period (7594 market days), 44 mammal species were traded. Thirteen species were on the International Union for Conservation of Nature (IUCN) Red List or protected under national legislation, and at least 1 threatened species was traded in 88 of the 89 markets. We used these data to identify market groups that traded similar species assemblages. Using cluster analyses, we detected 8 market groups that were also geographically distinct. Market groups differed in the diversity of species, evenness of species, and dominant, prevalent, and characteristic species traded. We mapped the distribution of number of threatened species traded across the study region. Most threatened species were sold in markets nearest 2 national parks, Korup National Park in Cameroon and Cross River in Nigeria. To assess whether the threatened‐species trade hotspots coincided with the known ranges of these species, we mapped the overlap of all threatened species traded. Markets selling more threatened species overlapped with those regions that had higher numbers of these. Our study can provide wildlife managers in the region with better tools to discern zones within which to focus policing efforts and reduce threats to species that are threatened by the bushmeat trade. Mapeo de Sitios Críticos para Especies Amenazadas Comercializadas en Mercados de Vida Silvestre en la Región de los Ríos Cross‐Sanaga  相似文献   
97.
Climate change mitigation, in the context of growing population and ever increasing economic activity, will require a transformation of energy and agricultural systems, posing significant challenges to global water resources. We use an integrated modelling framework of the water-energy-land-climate systems to assess how changes in electricity and land use, induced by climate change mitigation, impact on water demand under alternative socioeconomic (Shared Socioeconomic Pathways) and water policy assumptions (irrigation of bioenergy crops, cooling technologies for electricity generation). The impacts of climate change mitigation on cumulated global water demand across the century are highly uncertain, and depending on socioeconomic and water policy conditions, they range from a reduction of 15,000 km3 to an increase of more than 160,000 km3. The impact of irrigation of bioenergy crops is the most prominent factor, leading to significantly higher water requirements under climate change mitigation if bioenergy crops are irrigated. Differences in socioeconomic drivers and fossil fuel availability result in significant differences in electricity and bioenergy demands, in the associated electricity and primary energy mixes, and consequently in water demand. Economic affluence and abundance of fossil fuels aggravate pressures on water resources due to higher energy demand and greater deployment of water intensive technologies such as bioenergy and nuclear power. The evolution of future cooling systems is also identified as an important determinant of electricity water demand. Climate policy can result in a reduction of water demand if combined with policies on irrigation of bioenergy, and the deployment of non-water-intensive electricity sources and cooling types.  相似文献   
98.
The alteration of physico-chemical properties of sediment organic matter (SOM) incubated under current-harvesting conditions as well as no-current producing conditions over 120 days using sediment microbial fuel cell systems was examined. The SOM was microbially oxidized under anaerobic conditions with an electrode serving as a terminal electron acceptor. It was found that SOM around the electrochemically-active electrodes became more humified, aromatic, and polydispersed, and had a higher average molecular weight, along with its partial degradation and electricity generation compared to that for the original sediment. These changes in SOM properties were analogous to those commonly observed in the early stages of the SOM diagenetic process (i.e. humification). Such a humification-like process was evidently more stimulated when electrical current was produced than no-current condition. These new findings associated with microbially-catalyzed electricity generation may present a potential for the energy-efficient remediation, monitoring, and/or management of the geo-environment.  相似文献   
99.
Tropical wood is attracting global attention in the light of dwindling sources of industrial raw material supplies, increasing concern for conservation and growing requirements for huge investments. This study examines the changing character of the world hardwood trade, and the factors that will affect future supply, demand and price. It also considers the likely implications of recent large-scale attempts to grow tropical species for pulp, developments in microtechnology and biotechnology on wood, and the proposed international commodity agreement for tropical timber. The study emphasizes the need for huge investments on a global scale in afforestation and research to fully realize the potential of the tropical biomass.  相似文献   
100.
Water scarcity presents an obstacle to economic development in the western United States. Water rights markets help improve water allocation, allowing states to derive the highest economic benefit from available resources, and supporting new uses and economic development. However, the implicit (marginal) prices of water rights attributes are uncertain. To address this problem, we apply econometric analysis to a unique dataset to estimate the implicit values that market participants place on the attributes of shares of ditch company water rights in Colorado's South Platte River Basin. Our analysis demonstrates that ditch company share buyers value proximity of water diversion, reliability of water deliveries, and temporal flexibility of water use. To assess reliability we introduce the use of the coefficient of variation to capture, in one variable, the randomness of supply from ditch company shares that are not a single water right, but a portfolio of rights with different appropriation dates. Finally, we test and correct for spatial autocorrelation for the first time in a study of water market prices.  相似文献   
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