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Many mechanized crop producers and agribusinesses are fascinated with precision agriculture technology, but adoption has lagged behind the expectations. Among the reasons for slow adoption of precision agriculture technology is that initial users focused excessively on in‐field benefits from variable‐rate fertilizer application using regional average fertilizer recommendations. This article illustrates how greater use of site‐specific crop response information can improve variable rate input application recommendations. Precision agriculture is spatial information technology applied to agriculture. The technologies include global position systems (GPS), geographic information systems (GIS), yield monitoring sensors, and computer controlled within‐field variable rate application (VRA) equipment. Experimentation with these technologies is occurring everywhere there is large scale mechanized agriculture. Commercial use has been greatest in the US, where 43% of farm retailers offered VRA services in 2001. Except for certain high‐value crops like sugar beet, farmer adoption of VRA has been modest. The farm level profitability of VRA continues to be questionable for bulk commodity crops. The theoretical model and illustration presented here suggest that VRA fertilization has not yet reached its profitability potential. Most VKA field trials to date have relied upon existing state‐wide or regional input rate recommendations. Unobserved soil characteristics can potentially interact with an input to make its effect on yield vary site‐specifically within fields. Failure to use site‐specific response functions for VRA applications may lead to a misallocation of inputs just as great as that which results from using uniform applications instead of VRA. Agricultural economists have a long history of estimating output response to input applications. Several have started to develop tools to estimate site‐specific responses from yield monitor and other precision agriculture data. Likewise, agricultural economists have developed an important body of research results on information value based on managing variability—typically in temporal settings. With these tools, a major potential exists to develop further benefits from precision agriculture technologies that permit truly spatially tailored input applications. 相似文献
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Nick Hanley Douglas MacMillan Robert E. Wright Craig Bullock Ian Simpson Dave Parsisson Bob Crabtree 《Journal of Agricultural Economics》1998,49(1):1-15
This paper reports results from a study of the economic value of the conservation benefits of Environmentally Sensitive Areas (ESAs) in Scotland. The main novelty of the approach taken is in comparing two direct valuation methods, namely contingent valuation and choice experiments, to value these benefits. The Contingent Valuation Method (CVM) is well-established as a technique for valuing the sorts of landscape and wildlife enhancements associated with ESAs. The CVM experiment reported here uses a dichotomous choice format, and includes a new correction for part-whole bias. Choice experiments are much less used as an environmental valuation technique. We note several advantages of such experiments over CVM, and then report characteristic values and ‘programme values’ estimated using the method. This application brings to light some problems in applying the choice experiment method. Finally, we discuss the issue of benefits transfer in the context of these two approaches to valuation. 相似文献
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Weed control in the U.S. Midwest has become increasingly herbicide-centric due to the adoption of herbicide-tolerant (HT) crops in the 1990s. That integrated weed management (IWM) practices, including ecological and mechanical controls, are scarcely used is concerning. IWM would be a more sustainable form of farming for two reasons. First, it would reduce the negative health and environmental externalities associated with herbicide use. Second, it would reduce the selection pressure on weed populations and the development of weed resistance to some herbicides, thereby reducing the uncertainty of the long-term effectiveness of herbicidal weed control. In this context, we develop an economic framework to clarify the interplay among the different market failures that either contribute to the herbicidal ‘lock-in’ or make it problematic. We then analyse the evidence for and perceptions of these market failures based on twenty-four semi-structured interviews with farmers and experts conducted in 2017, as well as on discussions in the academic literature. To this end, we put into perspective the possible self-reinforcing effects in the adoption path of HT crops, such as increasing farm size, changes in farm equipment, increasing incentives for simplified crop rotations, and the loss of practical knowledge of IWM practices. 相似文献
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David S. Bullock Philip Garcia Kie-Yup Shin 《The Australian journal of agricultural and resource economics》2005,49(1):1-21
Procedures to measure the producer welfare effects of changes in an output price distribution under uncertainty are reviewed. Theory and numerical integration methods are combined to show how for any form of Marshallian risk-responsive supply, compensating variation of a change in higher moments of an output price distribution can be derived numerically. The numerical procedure enables measurement of producer welfare effects in the many circumstances in which risk and uncertainty are important elements. The practical ease and potential usefulness of the procedure is illustrated by measuring the producer welfare effects of USA rice policy. 相似文献
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Since most agricultural programs employ two or more policy instruments simultaneously, it is notable thai little research has attempted to find optimal instrument combinations and no research exists which evaluates the social costs (unrealized benefits) of combining instruments suboptimally. In our paper we report a simple and feasible method to find optimal policy instrument combinations, and we provide the first general, formal approach to measuring the social costs of suboptimal policy instrument combinations. Our approach is illustrated in an analysis for live major U.S. crops (corn, feed grains, wheat, rice, cotton). The simple model we employ for the illustration suggests that except lor the feed grains program, the observed programs combined policy instruments quite suboptimally. We conclude that agricultural economics research now can and should begin placing increased emphasis on studying optimal policy instrument combinations. 相似文献
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We use line integral theory to lay out in a more general theoretical framework the conditions under which it is possible to measure with market data the welfare effects of a change in a nonmarket good. We present in detail a numerical method of measuring the value of nonmarket goods using market data, under either weak neutrality or weak complementarity. Our numerical method is more flexible than the existing analytical method because it can be used with any well-behaved Marshallian demand function, and can be used even when the willig condition does not hold. 相似文献
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