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Registros recuperados: 58
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A Global Model for Agriculture and Bioenergy: Application to Biofuel and Food Security in Peru and Tanzania AgEcon
Elbehri, Aziz; McDougall, Robert; Horridge, Mark.
This paper describes a global model for agriculture and bioenergy (GLOMAB) that incorporates biomass, biofuels and bioelectricity sectors into the GTAP-Energy model by expanding the global GTAP database, production and consumption structures. Biofuels are separated between first- generation (sugar ethanol, starch ethanol) and second- generation (cellulosic ethanol) biofuels and associated biomass feedstocks (maize, sugar cane, crop residues, woody biomass). Beside biofuels, the model also incorporates bioelectricity (as separate form conventional electricity) which competes for the same biomass feedstocks with cellulosic ethanol sector (agricultural residues, woody biomass). With this broad-based representation of the bioenergy system likely to prevail...
Tipo: Conference Paper or Presentation Palavras-chave: Biofuels; Renewable Energy; Biomass; Agricultural Markets; Computable General Equilibrium (CGE); Food Security and Poverty; Resource /Energy Economics and Policy; C68; Q18; Q42; R14.
Ano: 2009 URL: http://purl.umn.edu/51914
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A minimum cross entropy model to generate disaggregated agricultural data at the local level AgEcon
Xavier, Antonio; Martins, Maria de Belem Costa Freitas; Fragoso, Rui Manuel de Sousa.
This work presents an entropy approach to disaggregate agricultural data at a local level. It comprises two different steps. In a first one, an information prior at disaggregated level based on experts’ opinions, available cartography of land use and biophysical data is created. In a second step, it’s used a minimum cross entropy process in order to manage these information inputs and to guaranty a solution compatible with all the different restrictions. The model was applied to the region of Algarve in the year of 1999, in order to disaggregate the data at the pixel and county level. Results show that the model was able to provide some satisfactory results since the estimated values obtained for the different areas revealed a good approximation to the...
Tipo: Conference Paper or Presentation Palavras-chave: Minimum cross entropy; Data disaggregation; Local level; Algarve; Agricultural policies; Agricultural and Food Policy; C11; C81; Q15; R14.
Ano: 2011 URL: http://purl.umn.edu/98991
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Aggregation and Calibration of Agricultural Sector Models Through Crop Mix Restrictions and Marginal Profit Adjustments AgEcon
Wiborg, Torben; McCarl, Bruce A.; Rasmussen, Svend; Schneider, Uwe A..
All agricultural sector models must deal with aggregation and calibration somehow. The aggregation problem involves treating a group of producers as if they all responded in the same way as a single representative unit. The calibration problem concerns making a model reproduce as closely as possible an empirically observed set of decision maker actions. This paper shows how both calibration and aggregation are addressed through crop mix restrictions combined with marginal profit adjust-ments.
Tipo: Conference Paper or Presentation Palavras-chave: Mathematical programming; Aggregation; Calibration; Crop mix; Marginal cost; Agricultural sector model; Agribusiness; C6; C61; Q1; Q11; Q17; Q18; R12; R13; R14.
Ano: 2005 URL: http://purl.umn.edu/24567
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An Account of Geographic Concentration Patterns in Europe AgEcon
Brulhart, Marius; Traeger, Rolf.
Using entropy indices and associated bootstrap tests, we describe the distribution of economic sectors across Western European regions over the 1975-2000 period. We decompose geographic concentration into its within-country and between-country components. In addition, we estimate centre-periphery gradients in sectoral location patterns and the impact of EU membership on countries' internal geography. It is found that manufacturing has become gradually more concentrated, although the locational bias towards central regions has become weaker. Conversely, market services have been relocating towards centrally located regions. EU integration appears to have strengthened countries' internal concentration trends.
Tipo: Working or Discussion Paper Palavras-chave: Geographic concentration; EU regions; Centre-periphery gradients; Entropy indices; Bootstrap inference; Community/Rural/Urban Development; R12; R14; F15.
Ano: 2003 URL: http://purl.umn.edu/26155
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Bayesian Model Averaging in the Context of Spatial Hedonic Pricing: An Application to Farmland Values AgEcon
Cotteleer, Geerte; Stobbe, Tracy; van Kooten, G. Cornelis.
Since 1973, British Columbia created an Agricultural Land Reserve to protect farmland from development. In this study, we employ GIS-based hedonic pricing models of farmland values to examine factors that affect farmland prices. We take spatial lag and error dependence into explicit account. However, the use of spatial econometric techniques in hedonic pricing models is problematic because there is uncertainty with respect to the choice of the explanatory variables and the spatial weighting matrix. Bayesian model averaging techniques in combination with Markov Chain Monte Carlo Model Composition are used to allow for both types of model uncertainty.
Tipo: Working or Discussion Paper Palavras-chave: Bayesian model averaging; Markov Chain Monte Carlo Model Composition; Spatial econometrics; Hedonic pricing; GIS; Urban-rural fringe; Farmland fragmentation; Environmental Economics and Policy; Farm Management; Land Economics/Use; R11; R15; C50; R14.
Ano: 2007 URL: http://purl.umn.edu/37046
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Conservation Payments under Risk: A Stochastic Dominance Approach AgEcon
Benitez, Pablo C.; Kuosmanen, Timo; Olschewski, Roland; van Kooten, G. Cornelis.
Updated version of REPA Working Paper 2004-05.
Tipo: Working or Discussion Paper Palavras-chave: Agroforest systems; Conservation payments; Land allocation; Portfolio diversification; Risk; Stochastic dominance; Environmental Economics and Policy; Land Economics/Use; Resource /Energy Economics and Policy; C73; O54; Q23; Q57; R14.
Ano: 2005 URL: http://purl.umn.edu/37024
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Deforestation AgEcon
Folmer, Henk; van Kooten, G. Cornelis.
Tipo: Working or Discussion Paper Palavras-chave: Environmental Economics and Policy; Resource /Energy Economics and Policy; Q10; Q23; Q58; R14.
Ano: 2006 URL: http://purl.umn.edu/37035
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Demand for Urban Forests and Economic Welfare: Evidence from the Southeastern U.S. Cities AgEcon
Zhu, Pengyu; Zhang, Yaoqi.
This study examines the relationship between urban forests and household income and population density in the 149 cities with populations over 40,000 in nine southeastern states. Our empirical results show that urban forest percentage across the cities has characteristics of the environmental Kuznets curve. We find that household income around $39,000 is a threshold that changes the relationship between income and urban forest coverage from negative to positive, whereas the impact of population density on urban forests is just the opposite, from positive to negative when population density is around 180 persons per square kilometer.
Tipo: Journal Article Palavras-chave: Environmental Kuznets curve; Environmental quality; Income; Land use; Population density; Tree canopy; Community/Rural/Urban Development; Environmental Economics and Policy; Land Economics/Use; C31; Q23; Q56; Q57; R14.
Ano: 2006 URL: http://purl.umn.edu/43758
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Desirability, Challenges, and Methods of Protecting Farmland AgEcon
Lynch, Lori.
Tipo: Journal Article Palavras-chave: Land Economics/Use; Q24; Q28; R14.
Ano: 2008 URL: http://purl.umn.edu/94683
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Determinants of Land-Use Change In the United States 1982-1997 AgEcon
Lubowski, Ruben N.; Plantinga, Andrew J.; Stavins, Robert N..
Changes in the use of land in the United States produce significant economic and environmental effects with important implications for a wide variety of policy issues, including protection of wildlife habitat, management of urban growth, and mitigation of global climate change. In contrast to previous descriptive and qualitative analyses of the trends in national land use, this paper uses an econometric approach to isolate the importance of historical changes in land-use profits and key government policies in determining national land-use changes from 1982 to 1997. The policies we examine are the Conservation Reserve Program (CRP) and total government payments to crop producers. We estimate a national-level discrete choice model of changes among the major...
Tipo: Working or Discussion Paper Palavras-chave: Land use; Econometric model; Counterfactual simulation; Conservation Reserve Program (CRP); Land Economics/Use; C53; Q1; Q24; R14; R15.
Ano: 2003 URL: http://purl.umn.edu/10714
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Did local government structure kill small town America? AgEcon
Warziniack, Travis.
This article examines the provision of public goods in an urban area and the effect voting has on the level and location of amenities throughout a city. It is particularly appropriate for small communities that must finance economic development projects with limited funds. The work presented is a result of working with rural communities throughout America that have seen their historic downtowns deteriorate as big box retail grows on the urban fringe. I find this shift in community development may be a result of the way local economic development is financed and projects are decided upon. Specifically, I find significant welfare losses associated with voting for a public good in space. Small public projects that would lead to community-wide welfare...
Tipo: Conference Paper or Presentation Palavras-chave: Open space; Spatial economics; Referendum; Voting; Community/Rural/Urban Development; Land Economics/Use; Political Economy; R10; R14.
Ano: 2010 URL: http://purl.umn.edu/60956
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Economic Dynamics of Tree Planting for Carbon Uptake on Marginal Agricultural Lands AgEcon
van Kooten, G. Cornelis.
As a result of the 1997 Kyoto Protocol, afforestation of agricultural lands can be expected to take on an important role in the CO2-emissions reduction policy arsenal of some countries. To date, identification of suitable (marginal) agricultural lands has been left mainly to foresters, but their criteria fail to take into account economic nuances. In this study, an optimal control model is used to determine the optimal level of afforestation in the western Canada. The results indicate that, while planting fast–growing trees for carbon uptake on marginal agricultural land may be important, the path dynamics matter in determining whether Canada can rely on afforestation to meet its obligations under Kyoto
Tipo: Working or Discussion Paper Palavras-chave: Afforestation and climate change; Optimal control model of land use; Economics of carbon sequestration; Agribusiness; Environmental Economics and Policy; Land Economics/Use; Q23; Q27; Q54; R14.
Ano: 2004 URL: http://purl.umn.edu/36995
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Ecotourism as a Means of Conserving Wetlands AgEcon
Pemberton, Carlisle A.; Mader-Charles, Kathleen.
The Nariva Swamp on the island of Trinidad in the Caribbean is being degraded due to increasing human activity. However, its conservation is desirable, as it is an internationally recognized wetland. The study examined an ecotourism project, with an emphasis on community participation, as a conservation approach to the Swamp, via benefit-cost analysis, where the benefits of conservation were measured by contingent valuation. Contingent valuation showed that the residents of Trinidad were willing to pay an average of $56 for conserving the Swamp. The analysis also showed that ecotourism represents an economically feasible use of ecologically fragile resources of this wetland.
Tipo: Journal Article Palavras-chave: Benefit-cost analysis; Contingent valuation of wetlands; Ecotourism; Q26; Q51; Q57; R14.
Ano: 2005 URL: http://purl.umn.edu/43521
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Expert Opinion versus Transaction Evidence: Using the Reilly Index to Measure Open Space Premiums in the Urban-Rural Fringe AgEcon
Cotteleer, Geerte; Stobbe, Tracy; van Kooten, G. Cornelis.
Due to economic and population growth farmland and to a lesser extend other undeveloped areas are under pressure in the urban-rural fringe in British Columbia, Canada. The objectives of this paper are to determine if residential property values near Victoria, BC include open-space premiums for farmland, parks or golf courses, and to determine if using assessed values instead of market prices of the property result in the same findings. We estimate a Seemingly Unrelated Regression (SUR) model with two hedonic pricing equations, one with actual market values as the dependent variable and one with assessed property values, and compare the resulting estimates of shadow prices for open space amenities. Furthermore, we take account of spatial autocorrelation and...
Tipo: Working or Discussion Paper Palavras-chave: Hedonic pricing models; Spatial dependence; Assessed property values; Open space; Community/Rural/Urban Development; Land Economics/Use; R14; R52; C21; Q20; H23.
Ano: 2008 URL: http://purl.umn.edu/37085
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Farmland Allocation along the Rural-Urban Gradient: The Impacts of Urbanization and Urban Sprawl AgEcon
Delbecq, Benoit A.; Florax, Raymond J.G.M..
In the vicinity of a city, farmers are confronted with increasing agricultural land prices and rents along the rural-urban gradient, but they concurrently enjoy the advantages associated with proximity to a larger and wealthier consumer base. We hypothesize that farmers transition from low-value, land-intensive \traditional" crops to high-value, labor-intensive \specialized" crops on parcels located closer to urban centers. Once returns to development of a parcel exceed the profits associated with farming, exurban farmers may sell their land for conversion to urban use. Urban pressure in the rural-urban fringe intensifies as cities expand. We differentiate between a gradual process of urban growth (or urbanization) and urban sprawl. Utilizing farmland...
Tipo: Conference Paper or Presentation Palavras-chave: Land use; Urban sprawl; Agriculture; Specialized crops; Spatial econometrics; Community/Rural/Urban Development; Land Economics/Use; C31; O13; Q15; R14.
Ano: 2010 URL: http://purl.umn.edu/61723
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Forest Conservation and Slippage: Evidence from Mexico's National Payments for Ecosystem Services Program AgEcon
Alix-Garcia, Jennifer Marie; Shapiro, Elizabeth N.; Sims, Katharine R.E..
Incentive-based programs to reduce deforestation are expected to play an increasingly important role in global efforts to protect ecosystems and sequester carbon but their environmental effectiveness is not clear. We investigate program effectiveness and slippage in the context of Mexico's national payments for hydrological services program, which pays private and communal landowners to maintain forest cover on enrolled lands. To measure program impacts, we use matched controls drawn from the program applicant pool to establish counterfactual deforestation rates in the absence of payments. We find statistically significant but small to moderate avoided deforestation impacts. To examine slippage of deforestation to nonenrolled lands, we develop a model of...
Tipo: Working or Discussion Paper Palavras-chave: Payments for environmental services; Payments for ecosystem services; Program evaluation; Slippage; Leakage; Incentive-based mechanisms; Mexico; Land use; Deforestation; Environmental Economics and Policy; Q12; Q24; Q57; R14; O13.
Ano: 2010 URL: http://purl.umn.edu/93045
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Forest Management Zone Design with a Tabu Search Algorithm AgEcon
Krcmar, Emina; Mitrovic-Minic, Snezana; van Kooten, G. Cornelis; Vertinsky, Ilan.
Increased conflicts between timber production and environmental protection led some analysts to advocate land-use segregation, often referred to as forest management zoning. The objective of zoning is to create ecologically desirable non-fragmented forest reserves and group timber production areas. We formulate an integer programming model of forest zoning that explicitly addresses clustering of spatial units allocated to timber production and reserve zones while also promoting separation of these zones. A tabu search algorithm is developed, implemented and tested using a case study. The case study results indicate that up to 5% of the net financial return is sacrificed with a 'satisfactory' grouping of units within each zone. A 'good' separation between...
Tipo: Working or Discussion Paper Palavras-chave: Forest planning; Integer programming; Reserves; Tabu search; Timber production; Zoning; Environmental Economics and Policy; Land Economics/Use; Resource /Energy Economics and Policy; C60; Q23; R14.
Ano: 2005 URL: http://purl.umn.edu/37022
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Harnessing the Forces of Urban Expansion - The Public Economics of Farmland Development Allowance AgEcon
Chau, Nancy H.; Zhang, Weiwen.
For decades, rapid urban expansion has led to concerns over the loss of cultivated land in rural China. This contrasts sharply with another salient feature of the Chinese land policy reform landscape that has gone on largely unnoticed - the addition of newly cultivated land in China through land development has consistently exceeded land conversion. In a model featuring fiscal decentralization, local governments as custodians of land use and development, along with a land development allowance policy instituted in 1998, we show that a land development allowance policy can harness the forces of urban expansion to encourage agricultural land development.
Tipo: Working or Discussion Paper Palavras-chave: Land development allowance; Fiscal decentralization; Inter-jurisdictional competition; Agricultural development; Community/Rural/Urban Development; H11; H77; P35; R5; R14; O18.
Ano: 2011 URL: http://purl.umn.edu/99416
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Hobby Farms and British Columbia'a Agricultural Land Reserve AgEcon
Stobbe, Tracy; Eagle, Alison J.; van Kooten, G. Cornelis.
Agricultural land protection near the urban-rural fringe is a goal of many jurisdictions, including British Columbia, Canada, which uses a provincial-wide zoning scheme to prevent subdivisions and non-agricultural uses of the land. Preferential taxes are also used to encourage agricultural use of the land. Small scale hobby farmers are present at the urban fringe near Victoria (the capital), both inside and outside of the Agricultural Land Reserve (ALR). The goal of this paper is to investigate whether hobby farms create problems for agricultural land preservation. We make use of a GIS (geographic information system) model to construct detailed spatial variables and analyse our parcel-level data set using an hedonic pricing model and a limited dependent...
Tipo: Working or Discussion Paper Palavras-chave: Hobby farmers; Agricultural Land Reserve; Geographical Information System; Urban-rural fringe; Zoning systems; Farmland fragmentation; Agricultural and Food Policy; Community/Rural/Urban Development; Crop Production/Industries; Farm Management; R11; R15; C50; R14.
Ano: 2008 URL: http://purl.umn.edu/42244
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Hobby Farms and Protection of Farmland in British Columbia AgEcon
Stobbe, Tracy; Eagle, Alison J.; van Kooten, G. Cornelis.
Tipo: Working or Discussion Paper Palavras-chave: Hobby farmers; Agricultural Land Reserve; Geographical Information System; Urban-rural fringe; Zoning systems; Farmland fragmentation; Agricultural and Food Policy; Land Economics/Use; R11; R15; C50; R14.
Ano: 2008 URL: http://purl.umn.edu/37048
Registros recuperados: 58
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