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61.
Does access to off-farm income complement or compete with agricultural production? This article explores the effect of off-farm income on agricultural production activities, using data from the 2003 Mexico National Rural Household Survey. We first discuss the theoretical conditions under which access to off-farm income may influence production in an agricultural household model. Instrumental-variable (IV) estimation methods are then used to test whether agricultural production activities, technologies, and input use differ between households with and without access to off-farm income. We find that off-farm income has a negative effect on agricultural output and the use of family labor on the farm, but a positive impact on the demand for purchased inputs. There is also a slight efficiency gain in households with access to off-farm income. Findings offer insights into how household production evolves as rural households increasingly engage in off-farm income activities. 相似文献
62.
Alan Swinbank 《Journal of Agricultural Economics》2009,60(3):485-503
The paper outlines EU policy on bioenergy, including biofuels, in the context of its policy initiatives to promote renewable energy to combat greenhouse gas emissions and climate change. The EU’s Member States are responsible for implementing EU policy: thus, the UK’s Renewables Obligation on electricity suppliers and its Renewable Transport Fuel Obligation and road‐fuel tax rebates are examined. It is unlikely that EU policy is in conflict with the WTO Agreement on Agriculture or that on Subsidies and Countervailing Measures, but its provisions on environmental sustainability criteria could be problematic. 相似文献
63.
Accounting for Negative,Zero and Positive Willingness to Pay for Landscape Change in a National Park
Nick Hanley Sergio Colombo Bengt Kriström Fiona Watson 《Journal of Agricultural Economics》2009,60(1):1-16
In contingent valuation, despite the fact that many externalities manifest themselves as costs to some and benefits to others, most studies restrict willingness to pay to being non‐negative. In this paper, we investigate the impact of allowing for negative, zero and positive preferences for prospective changes in woodland cover in two UK national parks, the Lake District and the Trossachs. An extended spike model is used to accomplish this. The policy implications of not allowing for negative values in terms of aggregate benefits are also investigated, by comparing the extended spike model with a simple spike making use of only zero and positive bids, and a model which considers positive bids only. We find that ignoring negative values over‐states the aggregate benefits of a woodland planting project by up to 44%. 相似文献
64.
Jon T. Biermacher B. Wade Brorsen Francis M. Epplin John B. Solie William R. Raun 《Agricultural Economics》2009,40(4):397-407
Plant-based precision nitrogen fertilizer application technologies have been developed as a way to predict and precisely meet nitrogen needs. Equipment necessary for precision application of nitrogen, based on sensing of growing wheat plants in late winter, is available commercially, but adoption has been slow. This article determines the expected profit from using a plant-sensing system to determine winter wheat nitrogen requirements. We find that plant-sensing systems have the potential to be more profitable than traditional nonprecise systems, but the existing system simulated was roughly breakeven with a traditional system. 相似文献
65.
Subject to a few agri‐environmental restrictions, municipal wastewater can be utilised for agricultural irrigation and river rehabilitation. This paper develops a single‐year Planning Model for a region in Israel which consists of a city and three potential wastewater consumers. The model incorporates, in one endogenous system, the economic, physical and biological relationships in the water–soil–plant–environment system and its objective is to maximise the regional social welfare. The model determines the optimal crop mix and the optimal allocation of the limited water and land resources among all potential users. Then, different allocation approaches from the concept of transferable utility games are applied to determine a reasonable and fair allocation of the additional net benefits which will be acceptable to all the players. The results support the collaboration among the economic entities and indicate economic and environmental advantages which can serve the decision‐makers. 相似文献
66.
The objective of this paper is to evaluate the effect of Plant Variety Protection (PVP) on the productive merit/yield increases of US seed varieties. As an example, we use wheat varieties, which are and have been available as both protected and unprotected under PVP from both the public and private sectors. We find evidence that PVP has contributed to the genetic improvement of wheat, using varietal trial data from Washington State. As the private open‐pollinated varieties exist only because of PVP and are higher yielding, these results indicate a clear public benefit from PVP. 相似文献
67.
John Quiggin 《Agricultural Economics》2010,41(Z1):121-132
The stabilization of global climate presents one of the most complex problems in public good provision the world has faced. Continuation of “business as usual” policies, leading to warming of more than 2 degrees over the next year, will produce significant damage to agricultural systems and catastrophic damage to the natural ecosystems that ultimately support agriculture. The best solution to the public goods problem is a “contract and converge” agreement in which the ultimate outcome is a common global entitlement to CO2 emissions per person. 相似文献
68.
Investment in soil conservation in northern Ethiopia: the role of land tenure security and public programs 总被引:5,自引:0,他引:5
A double hurdle statistical analysis of 250 farms in the Tigray region of Ethiopia reveals different causal factors for soil conservation adoption versus intensity of use. Farmers' reasons for adopting soil conservation measures vary sharply between stone terraces and soil bunds. Long‐term investments in stone terraces were associated with secure land tenure, labour availability, proximity to the farmstead and learning opportunities via the existence of local food‐for‐work (FFW) projects. By contrast, short‐term investments in soil bunds were strongly linked to insecure land tenure and the absence of local food‐for‐work projects. Public conservation campaigns on private plots reduced adoption of both stone terraces and soil bunds. Whereas capacity factors largely influenced the adoption decision, expected returns carried more influence for the intensity of stone terrace adoption (measured as metres of terrace per hectare). More stone terracing was built where fertile but erodible silty soils in higher rainfall areas offered valuable yield benefits. Intensity of terracing was also greater in remote villages where limited off‐farm employment opportunities reduced construction costs. These results highlight the importance of the right kind of public interventions. Direct public involvement in constructing soil conservation structures on private lands appears to undermine incentives for private conservation investments. When done on public lands, however, public conservation activities may encourage private soil conservation by example. Secure land tenure rights clearly reinforce private incentives to make long‐term investments in soil conservation. 相似文献
69.
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
70.
Ilya V. Surkov Alfons G. J. M. Oude Lansink Olaf van Kooten Wopke van der Werf 《Agricultural Economics》2008,38(3):363-373
Growth and liberalization of world trade have increased the risks of introduction of quarantine plant pests into importing countries. Import inspection of incoming commodities is a major tool for prevention of pest introductions related to world trade, but inspection capacities are limited. This article develops a theoretical and an empirical model for the optimal allocation of inspection effort for phytosanitary inspection of imported commodities when the inspecting agency has a limited capacity. It is shown that the optimal allocation of inspection effort equalizes marginal costs of pest introduction across risky commodity pathways. The numerical illustration finds the optimal allocation of inspection effort of chrysanthemum cuttings imported in the Netherlands. The numerical results suggest that ceteris paribus , greater inspection effort should be allocated to pathways whose inspection yields a greater reduction in the expected costs of pest introduction. The numerical results also suggest that import inspection has a high marginal benefit. In particular, we found that each additional euro of the inspection capacity decreases the expected costs of pest introduction from 18 to 49 euros, depending on the initial inspection capacity. 相似文献