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1.
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   

2.
In this study we develop a new methodological proposal to incorporate risk into a farm‐level positive mathematical programming (PMP) model. We estimate simultaneously the farm nonlinear cost function and a farmer‐specific coefficient of absolute risk aversion as well as the resource shadow prices. The model is applied to a sample of representative arable crop farms from the Emilia‐Romagna region in Italy. The estimation results confirm the calibration ability of the model and reveal the values of the individual risk aversion coefficients. We use the model to simulate different scenarios of crop price volatility, in order to explore the potential risk management role of an agri‐environmental scheme.  相似文献   

3.
The land‐use optimisation framework, NZFARM, has been promoted as a tool that can be used to assess the economic and environmental impacts of policy on regional land use. This paper outlines how methodological limitations presently restrict its capacity to provide meaningful insight into the relative value of alternative land‐use configurations. The model is calibrated using positive mathematical programming, which has been shown in the literature to result in models that yield arbitrary output outside of the calibrated baseline. There is a high likelihood that this is the case, as no validation appears to have been carried out. Significant model development will be required before NZFARM outputs can be used with any confidence to inform future policy development. We conclude with suggestions on how NZFARM and models of its kind can be further developed to improve their capacity for meaningful simulation.  相似文献   

4.
Evaluation of drought management in irrigated areas   总被引:4,自引:0,他引:4  
This paper focuses on the economic consequences of droughts for the irrigation sector. We develop a dynamic‐recursive mathematical programming farm model that assumes imperfect mobility of capital and labour as well as rational expectations about future water availability. The model is calibrated to 12 representative farms belonging to three irrigation communities of the Guadalquivir Basin (south Spain) and used to simulate the 1991–1997 period, which included 3 years of intense drought. Results indicate that the drought imposed significant costs on farmers, but show also that water managers partly exacerbated these costs by allocating excessive amounts of water to irrigators in the abundant years. The model is also used to evaluate the benefits of a perfect water supply forecast and to simulate the economic gains of a voluntary water banking scheme. Results show that the benefits resulting from the perfect forecast of water supply 1 year ahead would represent a relative gain of 5%. However, a voluntary banking system would allow farmers to increase their benefits by 32–82% depending on the supply system.  相似文献   

5.
This article employs a short‐term specification of the symmetric generalised McFadden (SGM) cost function capable of accommodating quasi‐fixed factors and variable returns. Temporary equilibrium and scale economies are investigated while maintaining the consistency of the estimated model with microeconomic theory and approximation properties. It also makes use of a two‐step procedure to estimate first the technology parameters and then time‐varying efficiency at farm level. No distributional assumptions are required on efficiency as we consider a fixed effect model. A balanced panel of Italian dairy farms during the years from 1980 to 1992 serves as the case study. The results suggest a rigid productive structure during the pre‐ and post‐quota period. Moreover, Italian milk producers are found to exhibit considerable excess capacity and rather low input technical efficiency.  相似文献   

6.
This study uses an agent‐based model for ex ante assessment of agricultural innovations. The model builds on whole farm mathematical programming (MP) and extends the methodology with a spatial representation of the system, the heterogeneity of farm households and landscapes, and the interaction between farm households. We apply the model in a northern Thai watershed to study the potential of four innovations to increase the profitability of litchi orchards. Cost‐benefit analysis shows that each innovation would increase the profitability of litchi growing; however, the results of the agent‐based model show that at current price levels these innovations alone would not be enough to stem the decline in the area under litchis. The model was validated and the sensitivity of the results tested for variations in the irrigated water supply and liquidity. We report on how farmers responded to these results and discuss the implications for other areas in northern Thailand.  相似文献   

7.
In this article, we analyze the role of subsistence‐oriented agriculture in Russia in the 1990s. We start out by discussing the diverging economic effects of the growth of subsistence agriculture in Russia since the transition process started. The quantitative analysis of this sector's role is carried out by means of an applied computable general equilibrium (CGE) model applying a 1994 social accounting matrix (SAM) as base year data. The novelty of the article is to disaggregate primary agricultural production not by products but by farm types, which enables us to distinguish their institutional and economic characteristics. The model also explicitly differentiates between marketed and subsistence consumption or formal and informal marketing activities of agricultural producers. We simulate two ex post and two ex ante experiments. The results of the first backward‐looking experiment highlight that Russia's subsistence agriculture was an important buffer against further agricultural output declines during transition and, hence, against food insecurity. A simulation, which looks into the effects of a devaluation of the Russian ruble, shows that the financial crisis should have increased the relative competitiveness particularly of large‐scale crop farms versus small‐scale farms. Two forward‐looking experiments indicate that efficiency enhancing institutional change would benefit both large‐scale and small‐scale farms. However, within small‐scale agriculture, a shift from subsistence to commercial agriculture would take place.  相似文献   

8.
This paper examines the relationships between the marginal abatement costs (MAC) of greenhouse gas (GHG) emissions on dairy farms and factors such as herd size, milk yield and available farm labour, on the one hand, and prices, GHG indicators and GHG reduction levels, on the other. A two‐stage Heckman procedure is used to estimate these relationships from a systematically designed set of simulations with a highly detailed mixed integer bio‐economic farm‐level model. The resulting meta‐models are then used to analyse how MAC vary across farm‐level conditions and GHG measures. We find that simpler GHG indicators lead to significantly higher MAC, and that MAC strongly increase beyond a 1–5% emission reduction, depending on farm attributes and the chosen indicator. MAC decrease rapidly with increasing farm size, but the effect levels off beyond a herd size of 40 cows. As expected, the main factors driving gross margins per dairy cow also significantly influence mitigation costs. Our results indicate high variability of MAC on real life farms. In contrast to time consuming simulations with the complex mixed integer bio‐economic programming model, the meta‐models allow the distribution of MAC in a farm population to be efficiently derived and thus could be used to upscale to regional or sector level.  相似文献   

9.
The decoupling of direct payments from production introduced in the reform of the Common Agricultural Policy is expected to make production decisions more market‐oriented and farmers more productive. However, ex‐post analyses of the productivity of farms have yet to uncover any evidence of a positive impact of the decoupling policy on farm productivity. Using Irish, Danish, and Dutch farm‐level data, we identify whether the decoupling policy has contributed to productivity growth in agriculture and farm product adjustment behavior. We find some evidence that the decoupling policy had significant positive effects on farm productivity and behavioral changes related to farm specialization.  相似文献   

10.
Lawmakers often subsidize farmers in times of financial distress. This article models this political impulse as a constraint on government farm policy, describing how ex ante government farm insurance can deter ex post "disaster relief" and improve production incentives by countering the moral hazard that otherwise prevails. Absent ex ante government policy, ex post relief takes the form of revenue insurance, which prompts excessive entry into farm production and under-production by operating farmers. Ex ante government policy can raise economic and political welfare by buying out low productivity farmers and offering profitable farmers a combination of revenue insurance, price supports, and a program participation fee.  相似文献   

11.
A new non‐parametric method to estimate a decision maker's coefficient of absolute risk aversion from observed economic behaviour is explained. The method uses the expected value‐variance (E‐V) framework and quadratic programming. An empirical illustration is given using Norwegian farm‐level data.  相似文献   

12.
In this article, I draw lessons from two quasi‐natural experiments (the transition process in former Communist countries and the rapid globalization of food chains) on the optimality of farms and agricultural structures more generally. I argue that (a) the farm structures that have emerged from the transition process are much more diverse than expected ex ante; (b) this diversity is to an important extent determined by economic mechanisms which are influenced by initial conditions and reform policies; (c) non‐traditional farm structures have played an important role during transition because they were optimal to address the specific institutional and structural constraints imposed by the transition process; (d) there is more diversity than often argued in the farms that are integrated in global food chains; (e) endogenous institutional (contracting) innovations in food chains may lock existing farm structures in a long‐run institutional framework; and (f) indicators based on farm structures are not a good measure of welfare effects of the globalization of food chains.  相似文献   

13.
One of the objectives of agricultural policy worldwide concerns the support of farm income. Common Agricultural Policy direct payments (DPs) are the main instruments to support farm income in the European Union. This article addresses their role in the concentration of farm income. This is done by calculating the Gini coefficient and its disaggregation in a large sample of Italian farms in the period between 2006 and 2007. Although this approach has been used to develop ex‐post analysis in previous studies, this article is innovative given that it is used here in an ex ante analysis aimed at evaluating the likely impact of a recent reform proposal. This latter requests changing the current model to a regional model of DPs application to make payment rates (i.e., payment per hectare) homogeneous among farms in the same region. The analysis shows that DPs and farm incomes are both very concentrated but that DPs allow for an income concentration reduction in Italian farms. The shift to a regional implementation reduces DPs concentration and, to a limited extent, farm income concentration. Of the considered regionalization scenarios, those that redistribute DPs among regions are the most effective in reducing concentration. The extension of the Gini considered approach to an ex ante setting seems effective because it provides insights that could feed the policy debate regarding the forthcoming reform.  相似文献   

14.
On June 2003 the final version of the Common Agricultural Policy Mid‐Term Review (CAP MTR) was published. The driving forces of this policy change include inter alia the compliance with World Trade Organization (WTO) negotiations' requirements, improvement of social support for agricultural policy, adjustment to budget constraints and adaptation of agricultural practices to environmental requirements. This article reviews how this policy performs in marginal areas regarding one of those objectives: the provision of environmental outputs related to agricultural activity. As an alternative to this reform, a policy based on agri‐environmental measures designed to maximize environmental outputs, is proposed. Both options are evaluated from a cost‐effectiveness point of view. Data from a farm survey and a positive mathematical programming model for a cereal steppes agro‐system in Spain are combined in order to simulate the effects of this reform and our alternative instrument on several environmental indicators. Results show that in marginal areas, where land abandonment is a clear threat, more environmental output can be achieved for the same cost, while maintaining, if not increasing, the levels of achievement for the other goals.  相似文献   

15.
This paper presents a bio‐economic model of Andit Tid, a severely degraded crop‐livestock farming system with high population density and good market access in the highlands of Ethiopia. Land degradation, population growth, stagnant technology, and drought threaten food security in the area. Drought or weather risk appears to have increased in recent years. The bio‐economic model is used to analyse the combined effects of land degradation, population growth, market imperfections and increased risk of drought on household production, welfare and food security. We find that the indirect effects of drought on household welfare through the impact on crop and livestock prices are larger than the direct production effects of drought. Provision and adoption of credit for fertiliser, although risky in itself, may lead to increased grain production and improved household welfare and food security. Provision of credit may have a negative effect on conservation incentives but this effect may be mitigated by linking a conservation requirement to the provision of credit for fertiliser.  相似文献   

16.
This paper explores the economic effects of biodiversity loss on marketable agricultural output for intensive agricultural systems, which require an increasing level of artificial capital inputs. A theoretical bio‐economic model is used to derive a hypothesis about the effect of the state of biodiversity on the optimal crop output both in the longer run and in the transitional path towards the steady‐state equilibrium. The hypothesised positive relationship between biodiversity stock and optimal levels of crop output is empirically tested using a stochastic production frontier approach, based on data from a panel of UK specialised cereal farms for the period 1989–2000. The results support the theoretical hypothesis. Increases in biodiversity can lead to a continual outward shift in the output frontier (although at a decreasing rate), controlling for the relevant set of labour and capital inputs. Agricultural transition towards biodiversity conservation may be consistent with an increase in crop output in already biodiversity‐poor modern agricultural landscapes.  相似文献   

17.
Agrobiodiversity can provide natural insurance to risk‐averse farmers by reducing the variance of crop yield, and to society at large by reducing the uncertainty in the provision of public‐good ecosystem services, for example, CO2 storage. We analyze the choice of agrobiodiversity by risk‐averse farmers who have access to financial insurance, and study the implications for agrienvironmental policy design when on‐farm agrobiodiversity generates a positive risk externality. While increasing environmental risk leads private farmers to increase their level of on‐farm agrobiodiversity, the level of agrobiodiversity in the laissez‐faire equilibrium remains inefficiently low. We show how either one of the two agrienvironmental policy instruments can cure this risk‐related market failure: an ex ante Pigouvian subsidy on on‐farm agrobiodiversity and an ex post payment‐by‐result for the actual provision of public environmental benefits. In the absence of regulation, welfare may increase rather than decrease with increasing environmental risk, if the agroecosystem is characterized by a high natural insurance function, low costs, and large external benefits of agrobiodiversity.  相似文献   

18.
This study examines the ex‐ante farm‐household effects of changes in family size, yield potential, and yield gaps using a farm‐household simulation model that reflects the economic and biophysical conditions of central Malawi. Disparities between growth in human population and crop yields present challenges for farm‐household crop production and income in sub‐Saharan Africa. We focus on the effect of growth in yield potential and a more efficient use of livestock manure as approaches to improving crop production and incomes in the face of looming population pressures. Our results suggest that, even without considering climate change, expected changes in population density and crop prices in 2050 mean that per person crop production and income may fall by 21% compared to 2013 values if yield potential and yield gaps remain constant. However, per person crop production and income could increase in 2050 by 8% compared to 2013 values if (1) growth rates of yield potential rise for maize by 1.13% each year and for legumes rise by at least 0.4% each year, and (2) farmers use livestock manure more efficiently. Our foresight approach to considering crop production at the farm‐household scale supplements macro‐scale analyses of the production dimension of food security.  相似文献   

19.
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   

20.
How consistent is a single farm payment system with rural development goals? A new economic geography model is used to compare coupled subsidies to ‘single farm payments’ effects on the location of farming, agro‐industry and non‐farm activity between rural and urban areas. This abstract model features a majority of employment in service sectors, farming vertically linked to manufacturing, and strong preferences for geo‐varieties. It appears that both coupled subsidies and single farm payments can decrease spatial agglomeration. But only the single farm payment policy raises welfare in both rural and urban regions of this stylised economy.  相似文献   

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