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1.
    
Data from a farm survey and choice experiment are used to value the benefits of Bt cotton in Pakistan. Unlike previous research on the economic impacts of Bt, which mostly concentrated on financial benefits in terms of gross margins, we also quantify and monetize health and environmental benefits associated with technology adoption. Due to lower chemical pesticide use on Bt cotton plots, there are significant health advantages in terms of fewer incidents of acute pesticide poisoning, and environmental advantages in terms of higher farmland biodiversity and lower soil and groundwater contamination. Farmers themselves value these positive effects at US$ 79 per acre, of which half is attributable to health and the other half to environmental improvements. Adding average gross margin gains of US$ 204 results in aggregate benefits of US$ 283 per acre, or US$ 1.8 billion for the total Bt cotton area in Pakistan.  相似文献   

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  总被引:5,自引:0,他引:5  
In an effort to improve productivity and profits, many farmers have replaced traditional livestock breeds with higher yielding alternatives. While such changes may bring about short‐term economic gains, the loss of traditional livestock breeds could result in the loss of an important genetic resource as a variety of important genetic traits adapted to local conditions gradually become less common in the population. This is a particular problem in Africa, where livestock make a substantial contribution to human livelihoods. Using the example of cattle in Kenya's pastoral livestock markets this study uses a choice experiment approach to investigate buyers' preferences for indigenous breeds such as the Maasai Zebu. The analysis employs a latent class approach to characterize heterogeneity in valuations both within and across respondents buying cattle for breeding, slaughter, or resale. The results show that there are at least three classes of buyers with distinct preferences for cattle traits and that most buyers favor exotic rather than indigenous breeds. Such preferences have implications for the conservation of indigenous cattle in Kenya and in other developing countries and suggest that some form of intervention may be required to ensure the preservation of this important animal genetic resource.  相似文献   

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China faces health and environmental problems associated with the use of agricultural chemicals, including pesticides. While previous studies have found that risk aversion affects pesticide use in China, they have focused primarily on commercial cotton farmers. In this study, we consider the case of smaller, semisubsistence and subsistence farmers in a poor and landlocked province of China (Yunnan). We use a field experiment to measure risk aversion and collect detailed data on farm production and input use to specifically ask whether risk aversion affects pesticide use, and whether this effect differs for subsistence farmers producing exclusively for home consumption versus semisubsistence farmers who produce both for home and the market. We find that risk aversion significantly increases pesticide use, particularly for subsistence farmers and for market plots by semisubsistence farmers. Further, this effect of risk aversion significantly decreases with farm size for subsistence farmers, but not for semisubsistence farmers, implying that pesticide use may be used to ensure sufficient food supply for home consumption. Finally, we find barriers to the use of pesticides for subsistence farmers, both in terms of financial constraints and economies of scale. This finding implies that risk‐mitigation strategies, such as crop insurance, may not target food security concerns of subsistence farmers. Given these different motivations for pesticide use, policymakers may wish to consider effective tools to support rural food security for farmers in the poorer regions of China in order to decrease pesticide use.  相似文献   

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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   

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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   

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In this article, we use a vintage‐capital model with risk of eviction to assess cocoa farmers' response to changes in their tenure security and to the introduction of a new, faster‐maturing cocoa variety. The model is calibrated with data from Cameroon in calendar year 2000, and then used to simulate the effects of institutional and technical change on farmer welfare and deforestation rates. Our findings can be summarized in three points. First, improved tenure security over cocoa fields increases farmers' consumption and welfare, but at the expense of more deforestation. Second, the introduction of new cocoa varieties with faster maturity and higher input response also unambiguously raises farmers' consumption and welfare. Doing so increases deforestation under insecure land tenure, but slows down deforestation under secure land tenure. Third, when introducing the two innovations together (more security and also new varieties), there is both an increase in welfare and a decline in deforestation. In sum, the availability of new cocoa cultivars calls for stronger tenure security, to accommodate investment in the new technology without increasing deforestation.  相似文献   

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The introduction of the EU Water Framework Directive requires policy to address non-point source pollution as part of an overall integrated strategy to improve the ecological status of water bodies. In this paper, we combine an economic optimisation framework with a dynamic simulation model of N transport in the Kennet Catchment to link decisions taken at the farm level to reductions in nitrate concentrations in the River Kennet. We examine a variety of policies targeted at reducing fertiliser use and changing the way in which farm land is used. We find that a tax on nitrogen emerges as the best policy both in terms of cost- and environmental effectiveness. Such a policy involves a considerable reduction in fertiliser use, as well as, a restructuring of land-use away from arable towards increased use of set-aside. Budgetary implications of such a radical move towards set-aside would be huge and hence unlikely to be politically palatable given the objective of reducing the EU budgetary allocation to agriculture. Additionally, the current rise in world demand for food may also mitigate calls for increasing the proportion of land taken out of agricultural production. Although the study succeeds in establishing a link between actions on the farm and nitrate concentrations in the stream water, further work is required to explore the effect of the retention of nitrates in the unsaturated zone and groundwater on this link.  相似文献   

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Using linear programming in bio‐economic farm modelling often results in overspecialised model solutions. The positive mathematical programming (PMP) approach guarantees exact calibration to base year data but the forecasting capacity of the model is affected by necessary but arbitrary assumptions imposed during calibration. In this article, a new PMP variant is presented which is based on less arbitrary assumptions that, from a theoretical point of view, are closer to the actual decision making of the farmer. The PMP variant is evaluated according to the predictions of the bio‐economic farm model, developed within the framework for integrated assessment of agricultural systems in Europe (SEAMLESS). The forecasting capacity of the model calibrated with the standard PMP approach and the alternative PMP variant, respectively, is tested in ex‐post experiments for the arable farm types of Flevoland (the Netherlands) and Midi‐Pyrenees (France). The results of the ex‐post experiments, in which we try to simulate farm responses in 2003 using a model calibrated to 1999 data, show that the alternative PMP variant improves the forecasting capacity of the model in all tested cases.  相似文献   

10.
High-value agriculture for exports is increasingly important in developing countries. In a case study of contract farming for exports of vegetables from Madagascar, strong spillover effects of these trade opportunities on land use are found to exist. Using a matched plot sampling design, the productivity of rice—the main domestically consumed staple—is shown to be two-thirds higher on fields that were contracted during the off-season for the production of vegetables. This increase in yields is linked to an increase of soil fertility due to the application of fertilizer and compost, which farmers did not use prior to the contracts. Although agricultural output goes up significantly, labor productivity stays the same, suggesting that there is greater labor absorption on existing land and the diffusion of this type of technology at a larger scale throughout Madagascar would be expected to substantially decrease incentives to deforest by increasing wages and to boost productivity of existing lands relative to newly deforested ones.  相似文献   

11.
    
This article presents a modelling system for synthesising heterogeneous productivity and nutrient loading potentials inherent in agricultural cropland for policy use. Phosphorus abatement cost functions for cropland farmers in a southeastern Minnesota watershed are metamodelled using frontier analysis. These functions are used to evaluate policies aimed at reducing nonpoint phosphorus discharges into the Minnesota River. Results indicate an efficiently targeted policy to reduce phosphorus discharge by 40% would cost US$167,700 or 844 per farm.  相似文献   

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This research characterizes the biological diversity of millet crops in the semiarid regions of India at the household and village‐community ( panchayat) scales of analysis, placing that evidence in the context of local seed systems. A set of seed system parameters that span formal and informal exchange and can be measured empirically are proposed. The analysis is based on data collected through sample surveys of farmers and traders in selected sites of Karnataka and Andhra Pradesh, combined with cultivar taxonomies developed with geneticists and applied to seed samples. Findings demonstrate that millet crop diversity levels at both scales of analysis are significantly influenced by seed system parameters, factors which related studies have omitted. In particular, the presence of active local (formal and informal) seed markets enhances millet richness among and within farming communities. Crop improvement strategies oriented toward local seed markets could provide important benefits and incentives to farm households living in these marginal environments. There is a need, however, for an enhanced theoretical understanding of local seed markets in analyzing crop variety choices and the diversity of materials grown in less favored environments.  相似文献   

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The dynamics of biomass growth implies that the yield of irrigated crops depends, in addition to the total amount of water applied, on irrigation scheduling during the growing period. Advanced irrigation technologies relax constraints on irrigation rates and timing, allowing us to better adjust irrigation scheduling to the varying needs of the plants along the growing period. Irrigation production functions, then, should include capital (or expenditures on irrigation equipment) in addition to aggregate water. We derive such functions and study their water-capital substitution properties. Implications for water demand and adoption of irrigation technologies are investigated. A numerical example illustrates these properties.  相似文献   

15.
Modeling linkages between climate policy and land use: an overview   总被引:1,自引:0,他引:1  
Agriculture and forestry play an important role in emitting and storing greenhouse gases. For an efficient and cost-effective climate policy, it is therefore important to include land use, land-use change, and forestry (LULUCF) explicitly in economy-climate models. This article gives an overview and assessment of existing approaches to include LULUCF into partial and general equilibrium economy-climate models. For each class of models, we describe different examples, their treatment of land, and their potential for and applicability to policy analysis, as well as their shortcomings. We identify data requirements and conceptual problems, and provide suggestions for future research.  相似文献   

16.
Land improvements with long pay-back periods are often delayed on leased agricultural land. The delay in improvements has been found to result in land degradation, decreased land productivity and environmental problems. An important question is thus how landowners would respond to regulations and mandates concerning land improvements. Based on a Finnish landowner survey, we analysed landowner choices under certain land improvement regulations, using the currently dominant choice of leasing land for agricultural use as the benchmark. The results indicated that land leasing will continue to increase in the future, but if the landowner mandate to co-finance costly land improvements is increased, landowners are predicted to respond significantly to these mandates and search for other land management options. Three heterogeneous landowner groups were identified based on their land use choices. Current leasers and amenity owners, in particular, were sensitive to land improvement mandates, and would avoid compulsory investment expenses by selling or afforesting their land.  相似文献   

17.
    
Relative agricultural productivity shocks emerging from climate change will alter regional cropland use. Land allocations are sensitive to crop profits that in turn depend on yield effects induced by changes in climate and technology. We develop and apply an integrated framework to assess the impact of climate change on agricultural productivity and land use for the U.S. Northern Great Plains. Crop-specific yield–weather models reveal crop comparative advantage due to differential yield impacts of weather across the region's major crops, that is, alfalfa, wheat, soybeans, and maize. We define crop profits as a function of the weather-driven yields, which are then used to model land use allocation decisions. This ultimately allows us to simulate the impact of climate change under the RCP4.5 emissions scenario on land allocated to the region's major crops as well as to grass/pasture. Upon removing the trends effects in yields, climate change is projected to lower yields by 33–64% over 2031–2055 relative to 1981–2005, with soybean being the least and alfalfa the most affected crops. Yield projections applied to the land use model at present-day input costs and output prices reveals that Dakotas’ grass acreage will increase by up to 23%, displacing croplands. Wheat acreage is expected to increase by up to 54% in select southeastern counties of North Dakota and South Dakota, where maize/soy acreage had increased by up to 58% during 1995–2016.  相似文献   

18.
  总被引:1,自引:0,他引:1  
This article investigates the effects of wheat genetic diversity and land degradation on risk and agricultural productivity in less favored production environments of a developing agricultural economy. Drawing production data from a household survey conducted in the highlands of Ethiopia, we estimate a stochastic production function to evaluate the effects of variety richness, land degradation, and their interaction on the mean and the variance of wheat yield. Ethiopia is a center of diversity for durum wheat and farmers manage complex variety mixtures on multiple plots. Econometric evidence shows that variety richness increases farm productivity. Variety richness also reduces yield variability but only for high levels of genetic diversity. Simulations with estimated parameters illustrate how planting more diverse durum wheat varieties on multiple plots contribute to improving farmer's welfare.  相似文献   

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Although land plays a crucially important role in economic development and structural transformation, the causes and consequences of the evolution of farming land have received scant attention in recent decades. In this article, I document global and regional changes in aggregate agricultural land use, per capita land use, and average farm sizes. The spatial distribution of global farming land has changed dramatically, with developed countries substantially reducing their share of global agricultural land, and land‐abundant developing countries substantially increasing their share. In per capita terms, we see a rather different pattern, with average farm sizes increasing in rich and more commercialized agricultural systems, and generally declining or staying constant in poorer and less commercialized systems. These outcomes are the result of complex processes that are not always well understood. I conclude the article by suggesting new, or neglected, areas of research that would facilitate a better understanding of these critically important developments.  相似文献   

20.
    
Historically, the Japanese farmland market has been strongly regulated, although fundamental changes in policy were introduced in 1967 and 1980. This article examines the relationship between farmland prices and rents in Japan for 1955–2000 using the cointegration procedure of Johansen et al. (2000) , which admits structural breaks. Results show the presence of a cointegrating relationship with a significant break in 1980. There is Granger‐causality from prices to rents, which suggests that rents are determined within an institutional setting according to farmland prices. The rent–price elasticity is unity, which supports the notion of efficiency in the farmland market.  相似文献   

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