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81.
Soil erosion, in its various forms, is caused or aggravated by agricultural activities. Mitigation of surface erosion comprises the construction of shelterbelts, fencing, riparian buffering, and stock reduction. Mitigation of mass‐movement erosion, in turn, takes the form of spaced planting of trees to maintain a persistent, healthy, and complete ground cover. In this article, we assess the economic implications to agriculture of the adoption of mitigation alternatives for erosion control in the Waikato District, New Zealand. The Waikato District presents a spatial pattern of erosion that affects profitability of dairy, and sheep and beef enterprises. We use the Universal Soil Loss Equation and the New Zealand Empirical Erosion Model to estimate erosion figures that are then fed into an economic‐focused, nonlinear, partial equilibrium mathematical programming model of New Zealand land use. Different scenarios are constructed for surface and mass‐movement soil erosion targets ranging from 0% to 50% below baseline levels. We find that achieving surface erosion targets is more expensive than mass‐movement targets, and results in different responses in regional‐level costs, land use, enterprise net revenue, and adoption of mitigation alternatives. 相似文献
82.
This paper describes an econometric assessment of wine market prices for 21 of the Crus Classés châteaux in the Bordeaux region of France. The model developed in the analysis attempts to define the relationship between factors that influence wine quality and those that influence wine prices. Characteristics of the models are: (1) climate influences on grape composition (acid and sugar levels), (2) grape composition influences on market prices, (3) subjective quality evaluations (Parker‐points) on market prices, and (4) the effects of age of the wine on market prices. The results indicate that composition levels of Merlot‐dominated wines are more climate sensitive than those from Cabernet Sauvignon‐dominated wines. Overall, warm, dry summers result in high sugar and low acid levels at harvest which in turn lead to higher quality wines. Wine market price sensitivity to Parker‐point ratings indicates that properties with high Cabernet Sauvignon‐dominated wines are highly dependent on the external ratings while Merlot‐dominated wines have a decreased rating sensitivity. Smaller properties tend to gain over proportionally from high ratings indicating great jumps in price from year to year. Additionally, châteaux that have experienced high ratings for past vintages exhibit great sensitivity to point steps in ratings for current vintages. Aging has a positive effect on Bordeaux wine pricing. This is due to the increasing maturity as well as the increasing absolute scarcity. Absolute scarcity of product is expressed by the size of the property, with small properties producing less per vintage and therefore having less in the market. Additionally, Merlot‐dominated wines exhibit more maturing potential and profit more from aging than Cabernet Sauvignon‐dominated wines. Average per château real annual profit ranges from 1 to 10%. High levels of grape ripeness, absolute scarcity, and smaller properties that are dominated by Merlot in their blend lead to the highest profits. Forecasts for a vintage not yet on the market indicates that 1995 is better than 1994 for both Cabernet Sauvignon and Merlot‐dominated wines, but that 1996 and 1997 are not as good as 1995, especially for Merlot‐dominated wines. 相似文献
83.
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
84.
Why do men and women adopt agricultural technologies at different rates? Evidence from Ghana suggests that gender‐linked differences in the adoption of modern maize varieties and chemical fertilizer result from gender‐linked differences in access to complementary inputs. This finding has important policy implications, because it suggests that ensuring more widespread and equitable adoption of improved technologies may not require changes in the research system, but rather introduction of measures that ensure better access for women to complementary inputs, especially land, labor, and extension services. 相似文献
85.
One of the objectives of agricultural policy worldwide concerns the support of farm income. Common Agricultural Policy direct payments (DPs) are the main instruments to support farm income in the European Union. This article addresses their role in the concentration of farm income. This is done by calculating the Gini coefficient and its disaggregation in a large sample of Italian farms in the period between 2006 and 2007. Although this approach has been used to develop ex‐post analysis in previous studies, this article is innovative given that it is used here in an ex ante analysis aimed at evaluating the likely impact of a recent reform proposal. This latter requests changing the current model to a regional model of DPs application to make payment rates (i.e., payment per hectare) homogeneous among farms in the same region. The analysis shows that DPs and farm incomes are both very concentrated but that DPs allow for an income concentration reduction in Italian farms. The shift to a regional implementation reduces DPs concentration and, to a limited extent, farm income concentration. Of the considered regionalization scenarios, those that redistribute DPs among regions are the most effective in reducing concentration. The extension of the Gini considered approach to an ex ante setting seems effective because it provides insights that could feed the policy debate regarding the forthcoming reform. 相似文献
86.
Fleur Wouterse 《Agricultural Economics》2010,41(5):385-395
This article uses a double bootstrap procedure and survey data from Burkina Faso in a two‐stage estimation to explore ways in which continental and intercontinental migration determine efficiency in cereal production of rural households. Findings suggest that continental migration has a positive relation and intercontinental migration no relation with technical efficiency. For continental migrant households, migration has removed surplus male labor, a cause for inefficiency in production. Intercontinental migration leads to a gender imbalance in the household, which cannot be compensated for by investments in farm equipment. The failure of intercontinental migration to transform cereal production from traditional to modern is attributed to an imperfect market environment. 相似文献
87.
Cheryl Doss Chiara Kovarik Amber Peterman Agnes Quisumbing Mara van den Bold 《Agricultural Economics》2015,46(3):403-434
Lack of clarity behind measurement and interpretation of statistics on gender and land leads to an inability to clearly articulate a policy response to the potential inequalities faced by women and men. This article sets out to explore, conceptually and empirically, the levels and relative inequalities in land rights between women and men in African countries. The first section of the article engages in a conceptual discussion of how to measure gendered‐land outcomes, what ownership and control mean in different contexts, and why attention to these factors is important for the development of gender and land statistics. The second section of the article systematically reviews existing evidence from microlevel large sample studies to summarize recent trends in land access, ownership, and control by sex. The third section presents new statistics from a variety of nationally representative and large‐scale unpublished data on gender and land in Africa. Results provide not only a nuanced understanding of the importance of measuring land indicators for gendered development in Africa and globally but also new statistics on a variety of land outcomes to aid stakeholders in the discussion of gender‐land inequalities. 相似文献
88.
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
89.
Do stronger intellectual property rights (IPRs) induce more agricultural trade? Based on panel data for 60 countries during 1990–2000 and using a dynamic panel data model, this article assesses whether and how national differences in IPRs affect the trade flow of planting seeds imports from the United States. The empirical results show that whether or not a country adheres to IPRs agreements has no discernible impact on planting seeds that are imported from the United States, implying that the strengthening of IPRs seems not to induce more agricultural trade. This result sheds some light on the debate in the theoretical literature on the importance of IPRs and trade. 相似文献
90.
M. Laura Donnet Dave D. Weatherspoon Charles B. Moss 《Journal of Agricultural Economics》2010,61(1):122-137
Food quality ratings can be used for product differentiation and strategic marketing. This article develops a differentiation measure based on the cross‐entropy of two distributions for speciality coffees. It examines whether quality ratings achieve their objectives for speciality coffee supply chains. The estimation, using e‐auctions data, indicates that the quality rating is more informative in the Cup of Excellence (CofE) relative to the Q auction. To determine significance, a statistical test for comparing the information measure across different e‐auctions and segments of the quality rating was developed. The significant difference between the two auctions is not a surprise as the auctions trade coffee lots of different volumes and the quality evaluation is more important in the case of the CofE, with its jury of renowned coffee experts. The total cross‐entropy measure of product differentiation shows that the 100‐point quality rating does not carry the same information content and meaning in the two different e‐auctions and their respective supply chains. The cross‐entropy measure of product differentiation is shown to be a good indicator of the information and the value created throughout the speciality food supply chain. 相似文献