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1.
There is a broad literature on the impact of Bt cotton adoption in different countries, but few studies have explicitly looked at environmental and health effects from an economic perspective. We analyse the impact of Bt cotton on environmental efficiency in Pakistan, using farm survey data and a doubly heteroskedastic stochastic production function framework. Negative environmental and health effects of chemical pesticide use are quantified with the environmental impact quotient. Bt‐adopting farms have higher cotton yields, while using lower pesticide quantities and causing less environmental damage. Bt farms are both technically and environmentally more efficient than non‐Bt farms. Bt adoption increases environmental efficiency by 37%. Achieving the same reduction in negative environmental and health impact without Bt would cost conventional cotton farmers US$ 54 per acre in terms of foregone yields and revenues (7% of total revenues). Extrapolating this shadow price of the technology's health and environmental benefits to the total Bt cotton area in Pakistan results in an aggregate value of US$ 370 million. These benefits are in addition to the profit gains for Bt‐adopting farmers. Our results suggest that Bt technology can contribute to sustainable agricultural development. 相似文献
2.
Xingliang Ma Melinda Smale David J. Spielman Patricia Zambrano Hina Nazli Fatima Zaidi 《Journal of Agricultural Economics》2017,68(2):366-385
Bt cotton remains one of the most widely grown biotech crops among smallholder farmers in lower income countries, and numerous studies attest to its advantages. However, the effectiveness of Bt toxin, which depends on many technical constraints, is heterogeneous. In Pakistan, the diffusion of Bt cotton occurred despite a weak regulatory system and without seed quality control; whether or not many varieties sold as Bt are in fact Bt is also questionable. We utilise nationally representative sample data to test the effects of Bt cotton use on productivity. Unlike previous studies, we invoke several indicators of Bt identity: variety name, official approval status, farmer belief, laboratory tests of Bt presence in plant tissue, and biophysical assays measuring Bt effectiveness. Only farmer belief affects cotton productivity in the standard production model, which does not treat Bt appropriately as damage‐abating. In the damage control framework, all Bt indicators reduce damage from pests. Biophysical indicators have the largest effect and official approval has the weakest. Findings have implications for impact measurement. For policy‐makers, they suggest the need, on ethical and productivity grounds, to improve variety information and monitor variety integrity closer to point of sale. 相似文献
3.
This article employs a propensity score‐matching approach to examine the direct effects of adoption of Bacillus thuringiensis (Bt) cotton on yields, pesticide demand, household income and poverty, using cross‐sectional data from a survey of farmers in the Punjab province of Pakistan. Generally, the findings reveal that adoption of the new technology exerts a positive and significant impact on cotton yields, household income and poverty reduction, and a negative effect on the use of pesticides. The positive and significant impact of the technology on yields and household income is consistent with the potential role of new agricultural technology in directly reducing rural poverty through increased farm household income. 相似文献
4.
In this article, the potential impacts of Bt eggplant technology in Indian agriculture are analyzed. Several proprietary Bt hybrids are likely to be commercialized in the near future. Based on field trial data, it is shown that the technology can significantly reduce insecticide applications and increase effective yields. Comprehensive farm-survey data are used to project farm-level effects and future adoption rates. Simulations show that the aggregate economic surplus gains of Bt hybrids could be around US$108 million per year. Consumers will capture a large share of these gains, but farmers and the innovating company will benefit too. As the company has also shared its technology with the public sector, Bt open-pollinated varieties might become available with a certain time lag. This would make the technology more accessible, especially for resource-poor farmers, entailing further improvements in welfare and distribution effects. The wider implications of the private–public technology transfer are discussed. Furthermore, the potential benefits for farmers' health resulting from reduced insecticide applications are examined, using an econometric model and a cost-of-illness approach. These benefits are worth an additional $3–4 million per year, yet they constitute only a small fraction of the technology's environmental and health externalities. More research is needed for comprehensive impact analysis. 相似文献
5.
This note reports on the results of a choice experiment survey of 400 people in England and Wales, conducted to estimate the value that society places on changes to the size of the badger population. The study was undertaken in the context of the possible need to reduce the badger population by culling to help control bovine tuberculosis in cattle. The study found that people were concerned about the problem of bovine tuberculosis in cattle, which was reflected in their willingness to pay to control the disease, and gave a relatively low value to changes in the size of the badger population (within limits). However, people did not like the idea of a policy that intentionally killed large numbers of badgers and had a relatively very high willingness to pay not to have such a policy. 相似文献
6.
Human behavior and the use of experiments to understand the agricultural,resource, and environmental challenges of the XXI century 下载免费PDF全文
Juan Camilo Cárdenas 《Agricultural Economics》2016,47(Z1):61-71
The use of laboratory1 experiments in economics, and their later deployment in the field as a tool for exploring how actual decision‐makers respond to information, incentives or institutions has brought a revolution to how we model economic systems, and design policies for them. This new century will bring challenges for the study of agriculture, natural resources and the environment, where it will be necessary to have a better understanding of human behavior, in a world where climate on the one hand, and land, labor and food markets are ever more unstable. This article reviews the intellectual history of a rich dialogue between theory and experiments with a particular focus on its relevance for agricultural, resource and environmental issues. Special attention will be given to the case of common‐pool resources where this dialogue between models, field work and laboratory experiments continues to provide a rich cross‐fertilization for the advance in the understanding of the economic systems that governs these resources. I will close by arguing that agricultural, environmental and resource economists will have to take part of this behavioral revolution by embracing experiments in their teaching, their research and their policy design. 相似文献
7.
We apply parametric and nonparametric methods to data from smallholders in Burkina Faso and assess the role that human capital characteristics play in the agricultural production process. Our results point to the technology‐changing nature of health, education, and experience. However, effects are rather heterogeneous. The productivity elasticity of health is much larger for households in the lowest landholding quintiles, while returns to experience are larger for households in the upper quintile. In terms of policy implications, our results suggest that productivity can be stimulated through the allocation of expenditure to social services that enhance certain types of human capital. Interventions aimed at improving the health status of households with smaller landholdings could have particularly strong welfare effects. 相似文献
8.
S. D. Gbègbèlègbè J. Lowenberg‐DeBoer R. Adeoti J. Lusk O. Coulibaly 《Agricultural Economics》2015,46(4):563-577
Genetically modified (GM) crops could increase economic growth and enhance living standards in Africa, but political issues have slowed the use of biotechnology. This is the first study that assesses the potential impact of GM crops in Africa while considering the preferences of producers and consumers towards GMOs as well as the income and price risks they face. The study uses a choice experiment to estimate the ex ante economic impact of a novel technology, Bacillus thuringiensis (Bt) cowpea, on producers and consumers in Benin, Niger and northern Nigeria. The experiment involves the simulation of a market transaction similar to those in open air markets in West Africa. During the market simulation, respondents are informed about the advantages and disadvantages, including health risks, of Bt cowpea. The results from the study suggest that cowpea growers and consumers in Benin and northern Nigeria prefer Bt to conventional cowpea for health safety reasons. The results estimate that social welfare in Benin, Niger and northern Nigeria would increase by at least US$11.82 per capita annually with Bt cowpea, if seed sectors are operating smoothly. With inefficiencies in seed sectors and the potential for cowpea acreage increase, the estimated social welfare increase in the region would be about US$1.26 per capita annually. 相似文献
9.
Rob Fraser 《Journal of Agricultural Economics》2009,60(1):190-201
This paper examines the issue of incentive compatibility within environmental stewardship schemes, where incentive payments to farmers to provide environmental goods and services are based on foregone agricultural income. The particular focus of the paper is land heterogeneity, either of agricultural or environmental value, leading to divergence between the actual and socially optimal level of provision of environmental goods and services. Given land heterogeneity, such goods and services are likely to be systematically over‐ or under‐provided in response to a flat rate payment for income foregone. 相似文献
10.
A model of adverse selection and moral hazard in agri‐environmental schemes is developed based on the input quota mechanism of Moxey et al. (Journal of Agricultural Economics, Vol. 50, (1999) pp. 187–202) and Ozanne et al. (European Review of Agricultural Economics, Vol. 28, (2001) pp. 329–347), rather than the input charge mechanism of White (Journal of Agricultural Economics, Vol. 53, (2002) pp. 353–360), but the variable fine of the latter rather than the fixed fine assumed by Ozanne et al. (European Journal of Agricultural Economics, Vol. 28, (2001) pp. 329–347) is used. Incentive‐compatible contracts, including the optimal probabilities of detection (and, therefore, monitoring frequencies and costs) for more and less efficient farmers, are identified. It is shown that the input charge and input quota approaches lead to identical outcomes – in terms of abatement levels, compensation payments, monitoring costs and probabilities of detection – confirming the equivalence of input quotas and input charges under asymmetric information. It is also shown that the optimal contracts are independent of the risk preferences of farmers with regard to being caught cheating. 相似文献