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	Provedor de dados Acta Botanica (2) Rev. Bras. Bot. (1) Autor Mamede,Maria Candida Henrique (2) Barth,Ortrud Monika (1) Makino-Watanabe,Hiroko (1) Melhem,Therezinha Sant'Anna (1) Palavra-chave Camarea (3) Malpighiaceae (3) Anatomia (2) Flores cleistógamas e casmógamas (1) Fruto (1) Morfologia (1) Pollen grains (1) Mais... Tipo do documento Info:eu-repo/semantics/article (3) Ano 1998 (1) 1993 (2) País Brazil (3) Idioma Português (3)		Ordenar por:  Relevância Autor Título Ano Registros recuperados: 96 Primeira ... 1 2 3 4 5 ... Última Heterogeneity among agent types and second-best management for non-market ecological services AgEcon Fenichel, Eli P.. Second-best management affects different agent types differently, and heterogeneity among agents may create instances when only second best management is feasible. Capital-theoretic bioeconomic modeling often has imposed representative agent assumptions that may not capture this heterogeneity. Interactions between agent heterogeneity and second-best management have received little attention. Such heterogeneity is particularly important when management actions do not directly affect extensive margin decisions. We employ a microparameter model in a dynamic bioeconomic model to incorporate agent heterogeneity and intensive and extensive margin decisions for a nonmarket good, recreational fishing. The model yields qualitatively different management... Tipo: Conference Paper or Presentation Palavras-chave: Entry-exit; Microparameter; Bioeconomics; Recreational fishing; Landing limits; Optimal control; Resource /Energy Economics and Policy; Q20; Q22; Q26. Ano: 2009 URL: http://purl.umn.edu/48995 Land Conversion, Interspecific Competition, and Bioinvasion in a Tropical Ecosystem AgEcon Barbier, Edward B.. This paper investigates the relationships among land-use change, biological invasion, and interspecific competition in a tropical ecosystem by linking a behavioral model of land conversion by agriculture and an ecological model of interspecific competition between a native species and an exotic invader. The model is used to examine how relative farm prices and access to forest areas influence land clearing and thus the ability of the invasive species to eliminate the native species. Simulations show that only a 20% rise in relative prices and a 2.75% increase in forest access are necessary for this outcome to occur. Tipo: Journal Article Palavras-chave: Biological invasion; Interspecific competition; Land clearing; Tropical ecosystem; Tropical forest; O13; Q20; Q24. Ano: 2007 URL: http://purl.umn.edu/37275 Definitions of Biodiversity and Measures of Its Value AgEcon Simpson, R. David. The destruction of natural habitats has prompted concerns about the loss of biological diversity. Regrettably, however, there is no consensus among either biologists or economists on the most meaningful measures of biodiversity. Fundamentally different definitions are useful in asking fundamentally different questions. Considerable attention has been given to the value of diversity in search models. A measure of "aggregate variability" is appropriate to such models. Values derived from search models tend to be well behaved; they exhibit diminishing returns in diversity. In contrast, a definition of diversity as "relative abundance" is more appropriate to more complex objective functions. Values derived in these models are not necessarily well behaved. The... Tipo: Working or Discussion Paper Palavras-chave: Biological diversity; Biodiversity; Diversity index; Abundance; Search; Variability; Consistency; Contingent valuation; Diminishing returns; Increasing returns; Environmental Economics and Policy; D43; D83; Q20. Ano: 2002 URL: http://purl.umn.edu/10551 AN AGENDA FOR THE STUDY OF LAND USE, WILDERNESS DESIGNATION, AND RESOURCE REGULATION IN THE AMERICAN WEST AgEcon Batabyal, Amitrajeet A.. Atemporal and intertemporal use of public lands, the determination of optimal levels of wilderness designation and habitat preservation, and the appropriate regulation of natural resources have all been "hot button" issues in the American West for quite some time now. In this paper, I propose and describe a research agenda which promises to yield interesting and useful new policy insights into these fractious resource issues. Tipo: Working or Discussion Paper Palavras-chave: Land use; Wilderness; Regulation; Research; Agenda; Land Economics/Use; Resource /Energy Economics and Policy; B41; Q20; Q25. Ano: 1995 URL: http://purl.umn.edu/28360 Farm Yields and Returns to Farmers From Seed Cotton: Does Zambia Measure Up? AgEcon Kabwe, Stephen; Tschirley, David L.. 1. Farm yields are one key indicator of the productivity of a cotton sector, and an important determinant of returns to farmers (and thus of cotton’s ability to reduce poverty) 2. Zambia’s relatively good performance on input credit provision means that it has been able to raise yields since reforms in 1994; yet the rate of increase has been slow, and yields remain well below those found in countries of West and Central Africa. 3. Average returns to farmers do not appear to be any higher in Zambia, with good performance on input credit provision, than in Tanzania, where input use and yields are low. 4. Zambia’s concentrated structure gives it the potential to substantially increase farm productivity, and for cotton to make but relatively little of this... Tipo: Report Palavras-chave: Food security; Food policy; Zambia; Cotton; Crop Production/Industries; Q20. Ano: 2007 URL: http://purl.umn.edu/54633 Does the Value of a Statistical Life Vary with Age and Health Status? Evidence from the United States and Canada AgEcon Alberini, Anna; Cropper, Maureen L.; Krupnick, Alan J.; Simon, Nathalie B.. Much of the justification for environmental rulemaking rests on estimates of the benefits to society of reduced mortality rates. Yet the literature providing estimates of the willingness to pay (WTP) for mortality risk reductions measures the value that healthy, prime-aged adults place on reducing their risk of dying, whereas the majority of statistical lives saved by environmental programs, according to epidemiological studies, appear to be the lives of older people and people with chronically impaired health. This paper provides an empirical assessment of the effects of age and baseline health on WTP for mortality risk reductions by reporting the results of two contingent valuation surveys designed to test the above hypotheses. One survey was... Tipo: Working or Discussion Paper Palavras-chave: Willingness to pay; Mortality; Contingent valuation; Age; Health status; Health Economics and Policy; D61; D62; Q20; Q26. Ano: 2002 URL: http://purl.umn.edu/10769 Structural Change, Environment and Well-being: Interactions Between Production and Consumption Choices of the Rich and the Poor in Developing Countries AgEcon Antoci, Angelo; Russu, Paolo; Ticci, Elisa. Replaced with revised version of paper 01/16/09. Tipo: Working or Discussion Paper Palavras-chave: Production; Consumption Choices; Welfare; D62; O11; O13; O15; O41; Q20. Ano: 2008 URL: http://purl.umn.edu/37671 Total Factor Productivity Growth when Factors of Production Generate Environmental Externalities AgEcon Vouvaki, Dimitra; Xepapadeas, Anastasios. Total factor productivity growth (TFPG) has been traditionally associated with technological change. We show that when a factor of production, such as energy, generates an environmental externality in the form of CO2 emissions which is not internalized because of lack of environmental policy, then TFPG estimates could be biased. This is because the contribution of environment as a factor of production is not accounted for in the growth accounting framework. Empirical estimates confirm this hypothesis and suggest that part of what is regarded as technology’s contribution to growth could be attributed to the use of environment in output production. Tipo: Working or Discussion Paper Palavras-chave: Total Factor Productivity; Sources of Growth; Environmental Externalities; Energy; Environmental Policy; Environmental Economics and Policy; O47; Q20; Q43. Ano: 2009 URL: http://purl.umn.edu/50405 The Economics of Sustainability: A Review of Journal Articles AgEcon Pezzey, John C.V.; Toman, Michael. Concern about sustainability helped to launch a new agenda for development and environmental economics and challenged many of the fundamental goals and assumptions of the conventional, neoclassical economics of growth and development. We review 25 years' of refereed journal articles on the economics of sustainability, with emphasis on analyses that involve concern for intergenerational equity in the long-term decision-making of a society; recognition of the role of finite environmental resources in long-term decision-making; and recognizable, if perhaps unconventional, use of economic concepts, such as instantaneous utility, cost, or intertemporal welfare. Taken as a whole, the articles reviewed here indicate that several areas must be addressed in future... Tipo: Working or Discussion Paper Palavras-chave: Economic efficiency; Intergenerational equity; Social optimality; Sustainable development; Environmental Economics and Policy; Q20; D60; D90. Ano: 2002 URL: http://purl.umn.edu/10683 Potential for Carbon Forest Plantations in Marginal Timber Forests: The Case of Patagonia, Argentina AgEcon Sedjo, Roger A.. With the advent of the Kyoto Protocol and its recognition of the use of forestry activities and carbon sinks as acceptable tools for addressing the issue of the build-up of atmospheric carbon, the potential role of planted forests as a vehicle for carbon sequestration has taken on a new significance. Additionally, the emergence of tradable emission permits and now tradable carbon offsets provides a vehicle for financially capturing the benefits of carbon emission reductions and carbon offsetting activities. In a world where carbon sequestration has monetary value, investments in planted forests can be made with an eye to revenues to (at least two) joint outputs: timber and the carbon sequestration services. The first section of this paper examines the... Tipo: Working or Discussion Paper Palavras-chave: Carbon sequestration; Forest plantations; Carbon offsets; Present value; Kyoto Protocol; Argentina; Developing countries; Environmental Economics and Policy; Q15; Q20; Q23. Ano: 1999 URL: http://purl.umn.edu/10661 Calculating the Costs of Environmental Regulation AgEcon Pizer, William A.; Kopp, Raymond J.. Decisions concerning environmental protection hinge on estimates of economic burden. Over the past 30 years, economists have developed and applied various tools to measure this burden. In this paper, developed as a chapter for the Handbook of Environmental Economics, we present a taxonomy of costs along with methods for measuring those costs. At the broadest level, we distinguish between partial and general equilibrium costs. Partial equilibrium costs represent the burden directly borne by the regulated entity (firms, households, government), including both pecuniary and nonpecuniary expenses, when prices are held constant. General equilibrium costs reflect the net burden once all good and factor markets have equilibrated. In addition to partial... Tipo: Working or Discussion Paper Palavras-chave: Social cost; Cost-benefit; Cost-effectiveness; Environmental regulation; Environmental Economics and Policy; Q20; Q28; H41; L50; D58. Ano: 2003 URL: http://purl.umn.edu/10762 Influencia social y sostenibilidad en el uso de recursos renovables AgEcon Almudi, Isabel; Choliz, Julio Sanchez. En este trabajo presentamos un modelo en el que las actividades extractivas referidas a un recurso natural renovable, si son abusivas, generan algún tipo de reacción social que modifica las preferencias sociales. Esta modificación es tenida en cuenta por el planificador a la hora de decidir cual es la asignación intertemporal óptima entre consumo y stock del recurso. Bajo estas nuevas condiciones, nos preguntamos cómo cambia el stock del recurso natural en el estado estacionario y qué puede decirse acerca de la posibilidad de sobreexplotación en comparación con los modelos tradicionales en los que no se considera reacción social. Los resultados obtenidos muestran que bajo estas nuevas condiciones el stock del estado estacionario aumenta y el comportamiento... Tipo: Journal Article Palavras-chave: Renewable Resources; Sustainability; Environmental Information; Overuse; Resource /Energy Economics and Policy; Q50; Q20; C61. Ano: 2006 URL: http://purl.umn.edu/8003 The Effects of Environmental Regulation On Technology Diffusion: The Case of Chlorine Manufacturing AgEcon Snyder, Lori D.; Miller, Nolan; Stavins, Robert N.. We use a hazard model to estimate the effect of environmental regulation on the diffusion of membrane cell production technology in the chlorine manufacturing industry. We estimate the effect of regulation on both the adoption of the membrane technology at existing plants and on the exit of existing plants using older technologies. We find that environmental regulation did affect the diffusion of the cleaner technology in the chlorine industry. However, it did so not by encouraging the adoption of membrane cells by existing facilities, but by reducing the demand for chlorine and hence encouraging the shutdown of facilities using the environmentally inferior options. Tipo: Working or Discussion Paper Palavras-chave: Regulation; Technological change; Environment; Hazard model; Environmental Economics and Policy; Q20; Q28; L50; L65. Ano: 2003 URL: http://purl.umn.edu/10554 Household Behavior Under Market Failures: How Natural Resource Management in Agriculture Promotes Livestock Production in the Sahel AgEcon Dutilly-Diane, Celine; Sadoulet, Elisabeth; de Janvry, Alain. Improved water harvesting and soil erosion control using the remarkably simple practice of contour stone bunding is shown to increase grain yields by 41% in low rainfall regions of Burkina Faso. Empirical results show that yield increases in food crops help foodbuying farm households import substitute in food consumption, reduce livestock production, and increase seasonal migration which is more compatible with seasonal agriculture than with the yearlong livestock activity. Self-sufficient households, by contrast, can take advantage of higher yields to free resources from food production and allocate these to expand their livestock economy, thus benefiting more from the region's comparative advantage. We also show that greater effectiveness in cooperation... Tipo: Working or Discussion Paper Palavras-chave: Farm household model; Natural resource management; Sahel; Consumer/Household Economics; Livestock Production/Industries; Resource /Energy Economics and Policy; 055; Q12; Q20. Ano: 2003 URL: http://purl.umn.edu/25061 Time and the Valuation of Environmental Resources AgEcon Smith, V. Kerry. This paper considers the modeling strategies that have been used to incorporate time in revealed and stated preference methods for valuing environmental resources. After reviewing a subset of the economic models for describing time as an input to household production; time in creating habits and persistence in demand for particular services of environmental resources, and time as offering an opportunity for future consumption, the overview suggests that time has been used as a complement in production or consumption to marketed goods in each of these frameworks. The paper suggests two possible alternatives. This structure along with further restrictions to preferences or technology implies that there are other strategies for using revealed preference data... Tipo: Working or Discussion Paper Palavras-chave: Time; Revealed preference; Complementarity; Environmental Economics and Policy; Q20; Q26; H40. Ano: 1997 URL: http://purl.umn.edu/10485 Sustainable Rural Development in Environmentally Protected Areas of Hungary and Austria: The Role of CAP payments AgEcon Katona-Kovacs, Judit; Dax, Thomas. Although there are steps in the direction that the application of Common Agricultural Policy (CAP) instruments in different regions has to take account of the territorial dimension, these have to be further improved. This aspect attains particular relevance in ecologically sensitive areas. The aim of the paper is to examine the role of CAP instruments in two National Parks from the aspect of sustainable rural development. The two selected National Parks are both very famous protected areas in Hungary and Austria, situated in very different landscapes and representing different types of national parks. The territorial distribution of the CAP Pillar 1 and Pillar 2 payments are analysed against the specific local role and the regional and national contexts.... Tipo: Conference Paper or Presentation Palavras-chave: National Parks; CAP; Territorial dimension; Community/Rural/Urban Development; Q20; Q01. Ano: 2008 URL: http://purl.umn.edu/44438 Registros recuperados: 96 Primeira ... 1 2 3 4 5 ... Última

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