共查询到20条相似文献，搜索用时 0 毫秒
1.
2.
In this study, we develop a conceptual bioeconomic model of floriculture production with aesthetic benefits, wherein optimal decision rules depend on an intertemporal economic objective to maximize profits subject to economic and biological processes. Necessary conditions of the model identify optimal trajectories (e.g., simultaneous, single, or cycling controls) that define decision rules and economic thresholds for profit maximizing growers producing crops with aesthetic attributes. The necessary conditions also highlight intertemporal trade‐offs between aesthetic benefits and expected future net benefits of arthropod stocks, which have important policy implications. The model is applied to the greenhouse production system of ivy geranium. 相似文献
3.
Christoph Schmitz Hans van Meijl Page Kyle Gerald C. Nelson Shinichiro Fujimori Angelo Gurgel Petr Havlik Edwina Heyhoe Daniel Mason d'Croz Alexander Popp Ron Sands Andrzej Tabeau Dominique van der Mensbrugghe Martin von Lampe Marshall Wise Elodie Blanc Tomoko Hasegawa Aikaterini Kavallari Hugo Valin 《Agricultural Economics》2014,45(1):69-84
Changes in agricultural land use have important implications for environmental services. Previous studies of agricultural land‐use futures have been published indicating large uncertainty due to different model assumptions and methodologies. In this article we present a first comprehensive comparison of global agro‐economic models that have harmonized drivers of population, GDP, and biophysical yields. The comparison allows us to ask two research questions: (1) How much cropland will be used under different socioeconomic and climate change scenarios? (2) How can differences in model results be explained? The comparison includes four partial and six general equilibrium models that differ in how they model land supply and amount of potentially available land. We analyze results of two different socioeconomic scenarios and three climate scenarios (one with constant climate). Most models (7 out of 10) project an increase of cropland of 10–25% by 2050 compared to 2005 (under constant climate), but one model projects a decrease. Pasture land expands in some models, which increase the treat on natural vegetation further. Across all models most of the cropland expansion takes place in South America and sub‐Saharan Africa. In general, the strongest differences in model results are related to differences in the costs of land expansion, the endogenous productivity responses, and the assumptions about potential cropland. 相似文献
4.
Being the two largest ethanol producers in the world, biofuel policies in Brazil and the United States affect both their domestic markets and the global food and biofuel economy. In this article we develop a price endogenous mathematical programming model to simulate and analyze the impacts of biofuel mandates and trade distortions on land use, agricultural commodity and transportation fuel markets, and global environment. We find that an 80% increase in total biofuel production from its 103 billion liter baseline level to the mandated 183 billion liter level in 2022 can be achieved with less than 2% increase in total cropland use in both countries. In the United States, this would occur with cellulosic biofuels meeting nearly half of the biofuels consumed and produced largely on cropland pasture and corn ethanol meeting the rest of the mandate and resulting in a 2% increase in corn price. In Brazil, the expansion in sugarcane production would be achieved by reducing land under pasture and a marginal increase in intensification of livestock production. In the aggregate, biofuel policies increase economic surplus in both countries by 1% and redistribute the benefits from agricultural consumers to agricultural producers and the fuel sector. Finally, we also find that full implementation of the mandates in North America, China, and the European Union would reduce the global life‐cycle global greenhouse gas emissions by about 5%. 相似文献
5.
6.
Understanding the relationship between soil fertility dynamics and crop response is conceptually appealing. Even more appealing is comprehension of the spatial and temporal heterogeneity of these connections over a production surface and across seasons. But gaining knowledge about these interactions is difficult because nutrient carryover dynamics and crop response to inputs are determined simultaneously on the one hand, and sequentially on the other. A second problem enters when crops are rotated, for example, the corn [Zea mays (L.) Merr.]–soybean [Glycine max (L.) Merr.] system commonly practiced in the U.S. Corn Belt. This article examines nutrient carryover–crop response dynamics using data from a corn‐soybean, variable rate nitrogen (N), and phosphorous (P) experiment conducted over five years in Minnesota, USA. Site‐specific corn response to N and P and soybean response to P is estimated with a P carryover equation. Estimates are used in a dynamic programming model to determine site‐specific optimal N and P fertilizer policies, soil P evolution, and profitability. The net present value of managing N and P site‐specifically is compared to a strategy in which these inputs are managed uniformly following Extension guidelines. The results suggest that when P carryover is accounted for in determining optimal P fertilizer rates, returns to the variable rate strategies are higher than returns to a uniform or whole‐field management strategy. 相似文献
7.
We model dynamic consumer choice in a stochastic optimal control framework and show conditions under which observable market share data possess the Markov property. Using 30 years of annual aggregate milk consumption data differentiated by fat content, maximum entropy is used to estimate nonstationary transition probabilities showing how consumer tastes and preferences have changed over time. The maximum entropy approach allows for the estimation of a 4 × 4 transition probability matrix for each year of the sample. Results suggest that skim milk was an absorbing state over most of the sample but that the trend toward skim milk has decelerated and possibly reversed itself since 1998. Our approach provides a useful complement to existing parametric approaches to demand analysis when data are limited or the problem is ill‐posed. 相似文献
8.
Ching-Cheng Chang 《Agricultural Economics》2002,27(1):51-64
This paper intends to estimate the potential impact of climate change on Taiwan's agricultural sector. Yield response regression models are used to investigate the climate change's impact on 60 crops. A price‐endogenous mathematical programming model is then used to simulate the welfare impacts of yield changes under various climate change scenarios. Results suggest that both warming and climate variations have a significant but non‐monotonic impact on crop yields. Society as a whole would not suffer from warming, but a precipitation increase may be devastating to farmers. 相似文献
9.
European water policy, as set out in the Water Framework Directive (WFD), requires all EU Member States to implement volumetric water pricing at rates that roughly cover the total costs of providing water services. The objective of this paper is to develop a methodology that, for the different types of farm in an irrigable area, will enable us to analyse the differential impact that a pricing policy for irrigation water would have. For this purpose, Multi-Attribute Utility Theory (MAUT) mathematical programming models were used. The methodology is implemented on a representative area in the Duero Valley in Spain. Our results show the usefulness of differential analysis in evaluating the impact of a water pricing policy. This allows significant differences in the evolution of agricultural incomes to be observed, as well as the recovery of costs by the State, demand for agricultural employment and the consumption of agrochemicals resulting from rising prices of irrigation water in various groups of farmers within a given irrigated area. 相似文献
10.
Sone Ekman 《Agricultural Economics》2005,32(3):297-309
This article focuses on how the linkages between various farm‐level decisions affect the choice of measures to reduce nitrogen leaching from crop production. A mathematical programming model is developed. The model considers not only management decisions that affect nitrogen leaching directly, but also other decision variables such as scheduling of field operations and machinery investments. A simplified analysis that ignores the latter management decisions, and the linkages between the various decisions, may result in abatement policies that are not cost‐effective because the policies will have other effects than expected. As an example, the empirical results show that subsidies to catch crops and spring ploughing may contribute to increased nitrogen load, quite contrary to the purpose of these subsidies. Further, it is noted that the characteristics of the production system make it costly to change land use, tillage practices, or fertilizer use drastically. Instead, cost‐effective nitrogen abatement includes a mix of various adjustments of farm‐level production practices. The EU set‐aside payment appears to reduce abatement costs. 相似文献
11.
There is interest in society in general and in the agricultural and forestry sectors concerning a land‐based role in greenhouse gas mitigation reduction. Numerous studies have estimated the potential supply schedules at which agriculture and forestry could produce greenhouse gas offsets. However, such studies vary widely in critical assumptions regarding economic market adjustments, allowed scope of mitigation alternatives, and region of focus. Here, we examine the effects of using different assumptions on the total emission mitigation supply curve from agriculture and forestry in the United States. To do this we employ the U.S.‐based Agricultural Sector and Mitigation of Greenhouse Gas Model and find that variations in such factors can have profound effects on the results. Differences between commonly employed methods shift economic mitigation potentials from –55 to + 85%. The bias is stronger at higher carbon prices due to afforestation and energy crop plantations that reduce supply of traditional commodities. Lower carbon prices promote management changes with smaller impacts on commodity supply. 相似文献
12.
Pinot Noir, a variety originating from Burgundy in France, is the most expensive category of table wine produced in North America. This article is aimed at analyzing its price determinants and focuses on climate, critical scores, and variables related to the winemaker. The main findings are as follows: (1) Pinot Noir prices are mainly determined by temperature and precipitation. General temperature increases are not beneficial. In fact, the optimal climate is similar to that in Burgundy. (2) The second most important variable is the winemaker. His or her skill and reputation have a significant impact on prices. (3) Expert knowledge, in the form of critical scores, has little explanatory value. 相似文献
13.
This article investigates the effects of sea level rise and climate change induced crop yield alterations on Taiwan as well as possible adaptation strategies. For sea level rise of up to 5 meters, as much as 4.9% of total acreage and 16% of rice acreage would be lost. The empirical findings show that the sea level damages range from NT$ 0.84 to 4.10 billion while crop yield losses range from NT$ 1.79 to 2.55 billion. We investigate alternative adaptation strategies finding crop yield technological progress and tariff reduction could significantly mitigate these effects. 相似文献
14.
Guillaume Pajot 《Journal of Forest Economics》2011,17(4):363-377
The extension of rotation lengths in forests has been proposed as an option for increasing carbon storage and contributing to climate change mitigation. This paper presents the results of a case study conducted on forests located in the southwest of France. The aim of this research was to assess the cost effectiveness of a subsidy/tax system on carbon fluxes. First, it is shown that such a mechanism leads forest owners to extend rotation lengths. However, cost effectiveness analysis shows that: (1) marginal social costs are more expensive than the private marginal costs of carbon sequestration; (2) marginal costs are higher when carbon stocks are discounted, ranging from 170.1 €/tC to 719.8 €/tC with discounted carbon stocks; and from 38.8 €/tC to 78.4 €/tC with undiscounted carbon stocks; (3) marginal costs are in the range of measures of the social value of carbon for France; (4) marginal costs increase with timber prices and increase with discount rate. 相似文献
15.
We summarize recent statistical analyses that link agricultural yields to weather fluctuations. Similar to other sectors, high temperatures play a crucial role in predicting outcomes. Climate change is predicted to significantly increase high temperatures and thereby reduce yields. How good are such models at predicting future outcomes? We show that a statistical model estimated using historic US data on corn and soybean yields from 1950 to 2011 is very capable of predicting aggregate US yields for the years 2012–2015, where 2012 was much hotter than normal and is expected to become the new normal under climate change. We conclude by discussing recent studies on the implication of predicted yield declines with a special focus on adaptation and commodity prices. 相似文献
16.
Thomas Berger Christian Troost Tesfamicheal Wossen Evgeny Latynskiy Kindie Tesfaye Sika Gbegbelegbe 《Agricultural Economics》2017,48(6):693-706
Climate variability with unexpected droughts and floods causes serious production losses and worsens food security, especially in Sub‐Saharan Africa. This study applies stochastic bioeconomic modeling to analyze smallholder adaptation to climate and price variability in Ethiopia. It uses the agent‐based simulation package Mathematical Programming‐based Multi‐Agent Systems (MPMAS) to capture nonseparable production and consumption decisions at household level, considering livestock and eucalyptus sales for consumption smoothing, as well as farmer responses to policy interventions. We find the promotion of new maize and wheat varieties to be an effective adaptation option, on average, especially when accompanied by policy interventions such as credit and fertilizer subsidy. We also find that the effectiveness of available adaptation options is quite different across the heterogeneous smallholder population in Ethiopia. This implies that policy assessments based on average farm households may mislead policy makers to adhere to interventions that are beneficial on average albeit ineffective in addressing the particular needs of poor and food insecure farmers. 相似文献
17.
Johannes Woelcke 《Agricultural Economics》2006,34(2):129-139
This article presents a bio‐economic household model, which has been developed to assess the potential impacts of agricultural intensification efforts on economic and ecological indicators in eastern Uganda. A study region in the Lake Victoria Crescent was selected with comparative advantages for intensive agricultural production: high agricultural potential, high market access, and high population density. However, current production is characterized by low input–output systems revealing a discrepancy between development opportunities and actual development outcomes. Based on a farmer participatory research approach, production methods were introduced in the study region aimed at fostering sustainable agricultural development. Data from two community surveys, two comprehensive household and plot level surveys, and farm‐trial data were used to develop and calibrate bio‐economic models for four representative household types. Model scenarios reveal that farm households in eastern Uganda would not pursue sustainable intensification under current socio‐economic conditions. The market environment has to be improved substantially, i.e., transaction and transportation costs have to be reduced, innovative credit schemes for smallholders have to be introduced, and alternative forms of labor acquisition have to be promoted, to provide sufficient economic incentives for the adoption of environmentally sound production methods. In addition, agricultural service provision needs to be reformed and more agricultural research is needed for new and better‐targeted technologies. 相似文献
18.
Stated choice models based on the random utility framework are becoming increasingly popular in the applied economics literature. The need to account for respondents' preference heterogeneity in such models has motivated researchers in agricultural, environmental, health, and transport economics to apply random parameter logit and latent class models. In most of the published literature these models incorporate heterogeneity in preferences through the systematic component of utility. An alternative approach is to investigate heterogeneity through the random component of utility, and covariance heterogeneity models are one means of doing this. In this article we compare these alternative ways of incorporating preference heterogeneity in stated choice models and evaluate the sensitivity of estimated welfare measures to which approach is selected. We find that a latent class approach fits our data best, but all the models perform well in terms of out-of-sample predictions. Finally, we discuss what criteria a researcher can use to decide which approach is most appropriate for a given data set. 相似文献
19.
The price elasticity of raw milk supply in Japan is estimated over time by a structural time-series model in state space form, and the changes in elasticity are tested by the diagnosing test of de John and Penzer in 1998. The supply function is modeled with a local linear trend and a strictly exogenous autoregressive distributed lag price. The seasonality in the data is adjusted by a structural time-series model. In the 1970–1997 period, there were major dairy policy changes in Japan: a production adjustment, related penalties, and two-tier pricing. Hokkaido is the region that mainly provides the supply of raw milk for milk products, while Tofuken is the region that mainly produces drinking milk. The estimated price elasticity in Hokkaido became stable after imposition of the production adjustment. On the other hand, price elasticity in Tofuken became stable after the inflation of the mid-1970s. Price elasticity is estimated to be more inelastic as well as more likely to converge in inelasticity in Hokkaido than in Tofuken. We discuss the relationship between changes in dairy policy and changes in price elasticity. 相似文献
20.
Dominic Moran Michael Macleod Eileen Wall Vera Eory Alistair McVittie Andrew Barnes Robert Rees Cairistiona F. E. Topp Andrew Moxey 《Journal of Agricultural Economics》2011,62(1):93-118
This article addresses the challenge of developing a ‘bottom‐up’ marginal abatement cost curve (MACC) for greenhouse gas (GHG) emissions from UK agriculture. An MACC illustrates the costs of specific crop, soil and livestock abatement measures against a ‘business as usual’ scenario. The results indicate that in 2022 under a specific policy scenario, around 5.38 Mt CO2 equivalent (e) could be abated at negative or zero cost. A further 17% of agricultural GHG emissions (7.85 Mt CO2e) could be abated at a lower unit cost than the UK Government’s 2022 shadow price of carbon [£34 (tCO2e)?1]. The article discusses a range of methodological hurdles that complicate cost‐effectiveness appraisal of abatement in agriculture relative to other sectors. 相似文献