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1.
According to economic theory, tenure security is an important determinant of agricultural investment and productivity. Land titling has been at the center stage of development efforts of many African countries to boost tenure security. We investigate the productivity impacts of the Ethiopian land registration and certification program, employing propensity score matching method in an effort to create a credible counterfactual. Consistent with theory, we find land registration and certification has robust positive effects on farm productivity. More tentatively, we identify the assurance effect as one probable channel for impact. Households with land certificates are more likely to adopt soil‐fertility management strategies on their plots than households without certificates.  相似文献   

2.
Agricultural exports and economic growth in less developed countries   总被引:1,自引:0,他引:1  
This article examines the contribution of agricultural exports to economic growth in less developed countries (LDCs). A sources‐of‐growth equation is developed from a dual economy model where agricultural and nonagricultural sectors are both divided into export and nonexport subsectors. This is then estimated using panel data for 62 LDCs for 1974–1995. Results provide evidence that there are significant structural differences in economic growth between low, lower‐middle, and upper‐income LDCs. Investment in the agricultural export subsector has a statistically identical impact on economic growth as investment in the nonagricultural export subsector. The marginal productivities in nonexport subsectors are over 30% lower than those in respective export subsectors. From a policy perspective, the results suggest that export‐promotion policies should be balanced.  相似文献   

3.
This article investigates how off‐farm income affects crop output market participation decisions and marketed surplus of smallholder farmers in Ethiopia. A double‐hurdle model is estimated using three waves of panel data from the Ethiopian Rural Household Survey. Unobserved heterogeneity is controlled for using a correlated random effect procedure and potential endogeneity of explanatory variables using a control function approach. The results show that off‐farm income has no significant influence on household crop output market participation. However, conditional on market participation, additional off‐farm earnings negatively affect the marketed surplus. This indicates that farmers use off‐farm earnings for consumption rather than for investment in agricultural production. Policy measures that promote rural investment may help increase returns to labor for land‐poor households participating in off‐farm work in the process of agricultural commercialization.  相似文献   

4.
The pressure on an already stressed water situation in South Africa is predicted to increase significantly under climate change, plans for large industrial expansion, ongoing rapid urbanization, and government programs to provide access to water to millions of previously excluded populations. This article employs a general equilibrium approach to examine the economy‐wide impacts of selected macro and water‐related policy reforms on water use and allocation, rural livelihoods, and economy at large. The analyses reveal that implicit crop‐level water quotas reduce the amount of irrigated land allocated to higher‐value horticultural crops and create higher shadow rents for production of lower‐value water‐intensive field crops, such as sugarcane and fodder. Accordingly, liberalizing local water allocation within irrigation agriculture is found to work in favor of higher‐value crops, and expand agricultural production and exports and farm employment. Allowing for water trade between irrigation and nonagricultural uses fuelled by higher competition for water from urbanization leads to greater water shadow prices for irrigation water with reduced income and employment benefits to rural households and higher gains for nonagricultural households. The analyses show difficult trade‐offs between general economic gains and higher water prices, which place serious questions on subsidizing water supply to irrigated agriculture, i.e., making irrigation subsidies much harder to justify.  相似文献   

5.
Agriculture accounts for over half of Ethiopian GDP, yet 'he case for agriculture as a focus of economic growth strategies must rely on identifying a set of intersectoral linkages through which agricultural growth contributes to the growth of nonagriculture in the Ethiopian economy. This article develops a four-sector numerical simulation model of economic growth in Ethiopia which permits the calculation of macroeconomic growth multipliers resulting from income shocks to agriculture, services, modern industry, and traditional industry. The resulting growth multipliers are 1.54 for agriculture. 1.80 for services, 1.34 for modern industry, and 1.22 for traditional industry. These results depict an economy in which intersectoral linkages operate on a highly uneven basis. These limits are reflected in the wide disparity between sectoral growth multipliers and by substantial differences in the patterns ol their decomposition. The policy relevance of these findings relate, in part, to the distributional implications of growth in particular sectors. Poverty in Ethiopia is disproportionately rural. An income shock to agriculture is clearly the most progressive choice, indicating the need to highlight agricultural development in growth strategies for Ethiopia. Yet, the simulation results further indicate that doing so imposes relatively little trade off against total benefit. While a $1 service sector income shock generates $0.80 in indirect benefits, a $1 agricultural income shock still generates $0.54 in indirect gains-a somewhat smaller benelit, but one likely to make the greatest possible impact on poverty reduction.  相似文献   

6.
Recent studies assessing plausible futures for agricultural markets and global food security have had contradictory outcomes. To advance our understanding of the sources of the differences, 10 global economic models that produce long‐term scenarios were asked to compare a reference scenario with alternate socioeconomic, climate change, and bioenergy scenarios using a common set of key drivers. Several key conclusions emerge from this exercise: First, for a comparison of scenario results to be meaningful, a careful analysis of the interpretation of the relevant model variables is essential. For instance, the use of “real world commodity prices” differs widely across models, and comparing the prices without accounting for their different meanings can lead to misleading results. Second, results suggest that, once some key assumptions are harmonized, the variability in general trends across models declines but remains important. For example, given the common assumptions of the reference scenario, models show average annual rates of changes of real global producer prices for agricultural products on average ranging between ?0.4% and +0.7% between the 2005 base year and 2050. This compares to an average decline of real agricultural prices of 4% p.a. between the 1960s and the 2000s. Several other common trends are shown, for example, relating to key global growth areas for agricultural production and consumption. Third, differences in basic model parameters such as income and price elasticities, sometimes hidden in the way market behavior is modeled, result in significant differences in the details. Fourth, the analysis shows that agro‐economic modelers aiming to inform the agricultural and development policy debate require better data and analysis on both economic behavior and biophysical drivers. More interdisciplinary modeling efforts are required to cross‐fertilize analyses at different scales.  相似文献   

7.
Payments for environmental services (PES) have gained wide popularity as approaches to promote environmentally friendly land use or agricultural production practices. Yet academics have also voiced concerns against seeing PES as a panacea. This article discusses whether PES is an appropriate and promising approach to promote so‐called “climate‐smart agriculture” (CSA) practices, which we define as agricultural production practices that contribute to CO2 emission reductions and/or removals and provide benefits to farmers via increased productivity and profits and reduced vulnerability to climate change. PES appears most promising for the promotion of CSA practices in small‐scale farming contexts with low incomes. Effective design, however, requires solid estimates of cost and benefit flows from CSA adoption over time, accounting for differences in socioeconomic and ecological conditions, and addressing the risk of leakage. Funding for such PES will likely have to come from public sources, and seems most promising where synergies with other objectives such as agricultural development, food security, and climate adaptation or other environmental services exist. The potential of alternative approaches for CSA support such as taxation with rebates for CSA practices, CSA‐related investment support such as microcredits, and hybrid approaches such as conditional microcredit should be further investigated.  相似文献   

8.
Assessments of climate change impacts on agricultural markets and land‐use patterns rely on quantification of climate change impacts on the spatial patterns of land productivity. We supply a set of climate impact scenarios on agricultural land productivity derived from two climate models and two biophysical crop growth models to account for some of the uncertainty inherent in climate and impact models. Aggregation in space and time leads to information losses that can determine climate change impacts on agricultural markets and land‐use patterns because often aggregation is across steep gradients from low to high impacts or from increases to decreases. The four climate change impact scenarios supplied here were designed to represent the most significant impacts (high emission scenario only, assumed ineffectiveness of carbon dioxide fertilization on agricultural yields, no adjustments in management) but are consistent with the assumption that changes in agricultural practices are covered in the economic models. Globally, production of individual crops decrease by 10–38% under these climate change scenarios, with large uncertainties in spatial patterns that are determined by both the uncertainty in climate projections and the choice of impact model. This uncertainty in climate impact on crop productivity needs to be considered by economic assessments of climate change.  相似文献   

9.
Agriculture is unique among economic sectors in the nature of impacts from climate change. The production activity that transforms inputs into agricultural outputs involves direct use of weather inputs (temperature, solar radiation available to the plant, and precipitation). Previous studies of the impacts of climate change on agriculture have reported substantial differences in outcomes such as prices, production, and trade arising from differences in model inputs and model specification. This article presents climate change results and underlying determinants from a model comparison exercise with 10 of the leading global economic models that include significant representation of agriculture. By harmonizing key drivers that include climate change effects, differences in model outcomes were reduced. The particular choice of climate change drivers for this comparison activity results in large and negative productivity effects. All models respond with higher prices. Producer behavior differs by model with some emphasizing area response and others yield response. Demand response is least important. The differences reflect both differences in model specification and perspectives on the future. The results from this study highlight the need to more fully compare the deep model parameters, to generate a call for a combination of econometric and validation studies to narrow the degree of uncertainty and variability in these parameters and to move to Monte Carlo type simulations to better map the contours of economic uncertainty.  相似文献   

10.
A theoretical model is developed to illustrate the economic incentives to invest in quality in markets with a dual reputation structure: private (firm reputation) and collective (regional reputation). Numerical dynamic programming techniques are then used to simulate firms’ strategic behaviour, and competitive outcomes are compared to the optimal investment of a regional planner. Market and product characteristics inducing asymmetric and/or sub‐optimal investment strategies, potentially destabilising for the region, are investigated.  相似文献   

11.
This issue of Agricultural Economics is a special issue containing articles on model performance in assessing the effects of climate change, bioenergy policy, and socioeconomics on agriculture. The contributions present results from a global economic model intercomparison activity undertaken as part of the AgMIP Project ( www.agmip.org ). The origins of the comparison activities can be traced to a project that was organized by the OECD in late 2010 to compare results from three models. The current phase of the research includes 10 models and was designed in part to support of the IPCC fifth assessment report (AR5). The special issue includes seven peer‐reviewed articles that present thematic results from a range of modeling strategies, with partial and general equilibrium modeling as a high level distinction but a myriad of differences within these two model types. A central common element is harmonization on biophysical effects using crop models and socioeconomic effects using drivers from the Shared Socioeconomic Pathways developed as part of the AR5 process. The special issue provides broad insights into how the modeling communities approached the interactions of climate, socioeconomics, bioenergy policy on agricultural outcomes, including land use, prices, consumption, and production.  相似文献   

12.
This study offers a "best evidence" approach to summarizing recent benefit-cost analyses of international agricultural research in Africa. First, from an extensive literature review and the resulting global inventory of impact studies, 23 studies are identified that calculate aggregate rates of return for Consultative Group on International Agricultural Research (CGIAR) and partner investments in Sub-Saharan Africa (SSA). These studies are then appraised against a review framework consisting of principles, criteria, and indicators for study rigor. Subsequently, the economic benefits reported by studies grouped on the basis of its analytical rigor are aggregated and set against total investment by the CGIAR and national agricultural research systems to determine if the total investment to date can be justified by documented benefits under a range of assumptions. As a result, the study finds that aggregate investment is justified under a fairly wide range of suppositions. Under all scenarios, the vast majority of documented benefits stem from a relatively limited array of activities with a majority of benefits stemming from biological control (80%). Close to 20% of total benefits result from crop genetic improvement, and less than 1% result from all other activities. The implications of these results for research investment strategies in SSA and impact assessment are discussed.  相似文献   

13.
We develop a mathematical programming model for the analysis of a nationwide waste‐management system based on composting of organic wastes. The model integrates a wide range of engineering, environmental, and economic factors, including estimated production functions based on agronomic experimental data, as well as demand functions for vegetative agricultural products. The model is applied to the case of Israel, comprising 14 groups of municipalities as the source of organic municipal solid waste and wastewater‐treatment sludge, 8 composting plants, and 13 agricultural regions; the latter constitute the source of livestock manure and are the consumers of compost to be potentially applied to 42 crops. From a social point of view, 90% of the compost's potential production was found to be warranted. This efficient solution, however, does not emerge under the base‐year‐observed situation, largely because of the absence of source separation of organic municipal solid waste and the farmers' lack of awareness of compost's advantages as a substitute for conventional fertilizers and as a soil‐amending product. Consequently, most of the organic wastes are disposed of by landfilling, resulting in a loss of $102 million per year in terms of net social benefits. While the consumers of agricultural products are expected to benefit from a shift from the base‐year situation to the efficient solution, most of their gain is expected to come at the expense of the farming sector. Nevertheless, the appearance of the efficient solution does not depend on administrative compensation payments, but on the removal of bottlenecks. Potential government intervention strategies to promote the change are analyzed.  相似文献   

14.
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   

15.
This paper analyses labour adjustment in and out of agriculture during transition to a market economy. A multinomial logit model is used to determine the factors that affect these processes. The results show that elderly, less educated and full‐time employees on a farm are more likely to continue with farming. Inflow of labour into agriculture is largely associated with the unemployment and retirement of farm household members. Age, education and investment in human capital are the key factors that improve the quality, mobility and flexibility of labour, which is crucial for efficient labour adjustment at the micro‐level and sector level. Better‐educated individuals are more likely to enter into employment in non‐agricultural, particularly service, activities.  相似文献   

16.
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   

17.
This article investigates the link between financing and investment in Ukrainian agriculture during economic transition. The main contribution of the study is to provide empirical evidence for the coexistence of financial constraints and soft budget constraints (SBCs). This is of particular importance because credit constraints and SBCs have completely different economic effects. The lack of differentiation between these forms of capital market imperfections yields overlapping effects of financing on investment and may therefore cause a misinterpretation of econometric results. Our empirical analyses are based on an econometric estimation of the Euler investment equations for 529 large farms from three Ukrainian regions between 2001 and 2005. The results confirm that financial variables significantly influence farms' investment, providing empirical evidence of an imperfect capital market in Ukrainian agriculture. It turns out that credit constraints in the Ukrainian agricultural sector are more important than SBCs. We show that the estimated level of financial constraints for profitable farms with access to loans is higher if both types of capital market imperfections are appropriately distinguished.  相似文献   

18.
Agriculture, pesticides and the ecosystem   总被引:1,自引:0,他引:1  
Economists have a good understanding of intra-economic interdependence and a mature methodology of modelling it. Ecologists focus on the complex and sensitive interactions of species in ecosystems. This paper’s objective is to suggest a new micro-foundation of ecosystem analysis based on economic methodology, to integrate the analyses of the ecosystem and the economy and focus on the interface of ecosystem-economy relations. Agriculture forms a major part of this interface. The basic assumption is that in the short run the individual organisms of all species behave as if they optimise their costly offensive and defensive activities given other organisms’ activities (Nash-behaviour).We consider an ecosystem with three species in a unidirectional food chain: buzzards feed on mice, mice feed on grain, and grain feeds on solar energy. A fourth species, humans, also feeds on grain. Humans intervene in the ecosystem in various ways. They can grow grain by using seed, farm labour, pesticides and possibly nature conservation measures to maintain buzzard habitat. Short-run ecosystem equilibrium is characterised, and it is shown, in particular, how this equilibrium depends on farming activities. We then link this ecosystem model to a simple model of an agricultural economy. Both systems are solved for equilibrium simultaneously. From an economic perspective the ecosystem induces positive and negative externalities in agricultural production and in consumer ‘green’ preferences.The inefficiencies of the competitive economy are identified and some possibilities to restore efficiency through corrective taxes or subsidies are briefly discussed. We also outline how short-run equilibria are connected through ecosystem stock-flow relationships. Due to the complexity of the inter-temporal analysis, the resulting ecosystem dynamics cannot be characterised in general analytical terms. It is a topic for future research to study the dynamics in numerical analysis to understand under which conditions the joint ecological and economic system is driven toward a (sustainable) steady state.  相似文献   

19.
This article aims to investigate the impacts of climate change and of lower and more volatile crop price levels as currently observed in the European Union (EU) on optimal management decisions, average income and income risks in crop production in Western Switzerland. To this end, a bioeconomic whole-farm model has been developed that non-parametrically combines the crop growth model CropSyst with an economic decision model using a genetic algorithm. The analysis focuses on the farm level, which enables us to integrate a wide set of potential adaptation responses, comprising changes in agricultural land use as well as crop-specific fertilization and irrigation strategies. Furthermore, the farmer's certainty equivalent is employed as objective function, which enables the consideration of not only impacts on average income but also impacts on income variability.The study shows that that the effects of EU crop prices on the optimal management decisions as well as on the farmer's certainty equivalent are much stronger than the effects of climate change. Furthermore, our results indicate that the impacts of income risks on the crop farm's optimal management schemes are of rather low importance. This is due to two major reasons: first, direct payments make up a large percentage of the agricultural income in Switzerland which makes Swiss farmers less vulnerable to market and climate volatility. Second, arable crop farms in Switzerland have by law to cultivate at least four different crops. Due to these diverse cropping systems and high government direct payments risk does neither under climate change, market liberalization nor combinations thereof, play a very decisive role in arable farming in Switzerland.  相似文献   

20.
A number of studies document gender differentials in agricultural productivity. However, they are limited to region and crop‐specific estimates of the mean gender gap. This article improves on previous work in three ways. First, data representative at the national level and for a wide variety of crops is exploited. Second, decomposition methods—traditionally used in the analysis of wage gender gaps—are employed. Third, heterogeneous effects by women's marital status and along the productivity distribution are analyzed. Drawing on data from the 2011–2012 Ethiopian Rural Socioeconomic Survey, we find an overall 23.4 percentage point productivity differential in favor of men, of which 13.5 percentage points (57%) remain unexplained after accounting for gender differences in land manager characteristics, land attributes, and access to resources. The magnitude of the unexplained fraction is large relative to prior estimates in the literature. A more detailed analysis suggests that differences in the returns to extension services, land certification, land extension, and product diversification may contribute to the unexplained fraction. Moreover, the productivity gap is mostly driven by non‐married female managers—particularly divorced women—; married female managers do not display a disadvantage. Finally, overall and unexplained gender differentials are more pronounced at mid‐levels of productivity.  相似文献   

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