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991.
Over the past dozen years, policymakers have largely abandonedlong-standing popular approaches for addressing risk in agriculturewithout fully resolving the question of how best to manage thenegative consequences of volatile agricultural markets. Thearticle reviews the transition from past policies and describescurrent approaches that distinguish between the trade-relatedfiscal consequences of commodity market volatility and the consequencesof price and production risks for vulnerable rural householdsand communities. Current policies rely more heavily on markets,even though markets for risk are incomplete in numerous ways.The benefits and limitations of market-based instruments areexamined in the context of risk management strategies, and innovativeapproaches to extend the reach of risk markets are discussed. 相似文献
992.
Nestor F. Gutierrez A. John De Boer Enrique Ospina 《Revue canadienne d'agroeconomie》1982,30(1):61-70
Recent theoretical and empirical studies of beef cattle producers by Barros, Jarvis, Nores, Reutlinger, and Yver have focused on producers' supply response assuming cattle represent consumption goods and capital goods. To differentiate producer price response for cattle sold as consumption goods and cattle retained as capital goods requires data on herd and slaughter age-sex structure. This has limited the range of econometric work which could be carried out in many developing countries. This study utilizes a time series of the Colombian cattle herd which was recently constructed by Rivas and Valdes and which has the necessary age-sex and slaughter data to develop a complete system of structural equations representing the simultaneous determination of demand and supply for Colombian cattle over the 1950–1970 period. 相似文献
993.
Robert F. J. Romain John B. Penson jr. Rémy E. Lambert 《Revue canadienne d'agroeconomie》1987,35(2):373-385
Among the different factors pertaining to the demand for durable inputs in agriculture, the way the input depreciates over time is an important issue. This study investigates four alternative capacity depreciation patterns for farm tractors. While published estimates from government agencies implicitly assume convex capacity depreciation patterns, the results of this study demonstrate that the use of agricultural engineering data which depict a concave rather than convex pattern better reflect farmers' investment decisions. An implicit rental price measure is also proposed to account for the fact that the purchase price of a durable input is not an appropriate measure of the implicit rental cost of the asset.
Parmi les facteurs déterminants de la demande pour les biens durables en agriculture, la rapidité avec laquelle I'intrant se déprécie est certainement importante lors des décisions d'investissement. La présente etude analyse quatre différents scénarios de dépréciation pour les tracteurs agricoles au Canada. Bien que les données publiées par les agences gouver-nementales supposent implicitement que les biens durables se déprécient à un taux annuel constant, les résultats de cette etude montrent que I'utilisation de données basées sur la valeur productive de I'intrant telle que calculée sur une base expkrimentale donne de meil-leurs résultats statistiques dans I'estimation de la demande pour les tracteurs agricoles. De plus, une mesure du coût implicite de I'intrant est également proposée pour tenir compte du fait que le prix d'achat n'est pas une mesure appropriée dans I'analyse de la demande pour un bien durable. 相似文献
Parmi les facteurs déterminants de la demande pour les biens durables en agriculture, la rapidité avec laquelle I'intrant se déprécie est certainement importante lors des décisions d'investissement. La présente etude analyse quatre différents scénarios de dépréciation pour les tracteurs agricoles au Canada. Bien que les données publiées par les agences gouver-nementales supposent implicitement que les biens durables se déprécient à un taux annuel constant, les résultats de cette etude montrent que I'utilisation de données basées sur la valeur productive de I'intrant telle que calculée sur une base expkrimentale donne de meil-leurs résultats statistiques dans I'estimation de la demande pour les tracteurs agricoles. De plus, une mesure du coût implicite de I'intrant est également proposée pour tenir compte du fait que le prix d'achat n'est pas une mesure appropriée dans I'analyse de la demande pour un bien durable. 相似文献
994.
995.
996.
William E. Nganje Dean A. Bangsund F. Larry Leistritz William W. Wilson Napoleon M. Tiapo 《Review of Agricultural Economics》2004,26(3):332-347
Fusarium Head Blight is a fungus affecting wheat and barley in the upper Midwest region of the United States. The purpose of this study is to estimate the direct and secondary regional economic impacts of Fusarium Head Blight infestations from 1998 to 2000. Cumulative direct production and price impacts from Fusarium Head Blight in hard red spring, soft red winter, durum wheat, and barley are estimated at $871 million over the period, with secondary economic losses of $1.8 billion. The total impacts of $2.7 billion were concentrated in North Dakota and Minnesota, which accounted for 55% of total losses over the period. 相似文献
997.
Because of tensions on fossil energy and phosphorus markets, the rise in fertilizer prices observed during the last decades may continue in the future, putting into question production pathways relying heavily on crop intensification. To evaluate how, in this context, economic choices may alter crop yields, we first construct different fertilizer price scenarios to 2050 based on an econometric relation with oil and gas prices. Other possible scenarios, such as the continuation of historical trends, are also considered. The resulting changes in fertilizer price range between +0.8% and +3.6% per year over the 2005–2050 period. These scenarios are tested in a global land‐use model incorporating an endogenous representation of the land–fertilizer substitution. We find that the supply‐side response to rising fertilizer prices could lower crop yields in 2050 from ?6% to ?13%, with a corresponding increase in global cropland area ranging between 100 and 240 Mha if the demand for food and nonfood products has to be met. The sensitivity of these results is tested with regard to assumptions on food consumption, change in potential yield and nutrient use efficiency. 相似文献
998.
Anaerobic digesters for livestock operations are receiving attention for energy production and odor control. A farm-based digester went into operation in September 1999, on an 800-cow dairy farm in Minnesota. The goals of this paper are to analyze the contribution that a digester system can make to dairy farm profitability, and to demonstrate the impact of government and utility subsidies on profitability. Results indicate that the current selling price of electricity is not sufficient to justify building an anaerobic digester in most cases unless there is a subsidy or significant nonenergy market benefits. 相似文献
999.
1000.
Urban Sprawl and Farmland Prices 总被引:1,自引:0,他引:1
Grigorios Livanis Charles B. Moss Vincent E. Breneman Richard F. Nehring 《American journal of agricultural economics》2006,88(4):915-929
A theoretical model of farmland valuation is developed to explicitly account for three effects of urban sprawl: conversion of farmland to urban uses, effect on agricultural returns, and speculative effect as represented by farmland conversion risk. This model is estimated using county-level data in the continental United States. Evidence is found for all three effects of urban sprawl on farmland values. Counties more accessible to major urban centers have higher net agricultural returns. Subsidiary evidence supports that the latter effect may be attributed to survival of (or conversion to) high-valued agriculture around urban centers. 相似文献