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991.
There are a number of significant environmental impacts that arise from agricultural practices that may be influenced by policy. A Strategic Environmental Assessment Method (SEAM) is described which aims to assess the environmental impacts of agricultural policy and aid the development of more sustainable policy formulation. The method addresses the issues of selecting appropriate performance criteria and measurements, and makes use of effect-damage functions and targets to determine the significance of potential impacts in relation to sustainability. A set of profiles is produced, describing the environmental performance of a specific policy. A confidence assessment system (CAS) is also described which provides details about the quality of the assessment and areas of uncertainty. SEAM provides information about impacts in simple format that can be easily used in decision making. It can identify environmental trade-offs and provides a holistic view that is essential when making decisions that affect the environment.  相似文献   
992.
Land use optimization in watershed scale   总被引:2,自引:0,他引:2  
Managing a watershed for satisfying the inhabitant's demand is a difficult task if one has to maintain a reasonable balance between usually conflicting environmental flows and demands. The solution to these complex issues requires the use of mathematical techniques to take into account conflicting objectives. Many optimization models exist for general management systems but there is a knowledge gap in linking practical problems with the optimum use of all land resources under conflicting demands in a watershed. In the present study, an optimization problem has been formulated for the Brimvand watershed, Iran, comprising ca. 9572 ha to find out the most suitable land allocation to different land uses, viz. orchard, irrigated farming, dry farming and rangeland targeting soil erosion minimization and benefit maximization.  相似文献   
993.
Applying econometric analysis to a model recently used by Parish, this article examines the short-run implications for consumers and producers of the pricing decisions of the Western Australian Egg Board over the period 1953-54 to 1962-63.  相似文献   
994.
Most forest crops in real life are mixtures of species and the theory of optimal economic rotations as presented in literature does not quite apply to them. A model for determining the optimal economic rotation of a mixed species even-aged forest has, therefore, been developed. Data for jack pine and black spruce from an actual forest managed by a forest company have been used to demonstrate the value of the model. It has been concluded that at high discount rates faster growing components of a mixture should be given more importance in deciding the common optimal rotation. At low discount rates the slower growing components need to be emphasized.
La majeure partie de la récolte forestière consiste en réalité en mélanges d'essences et la théorie des rotations économiques optimales ne s'y applique pas tout à fait; Un modèle pour déterminer la rotation économique optimale a done áté developpé. Afin de démontrer la valeur de ce modéle, on s'est servi de données provenant d'une forêt de pin gris et d'épinette noire gárée par une compagnie forestiére. On a con-clu qu'avec des taux d'intérět éleves, on devrait donner plus d'importance aux constituants dont la croissance est la plus rapide lorsqu'il s'agit de décider la rotation commune optimale. Par contre, avec des taux d'tntérêt bas, on doit faire valoir les constituants à croissance plus lente.  相似文献   
995.
996.
There are many common characteristics between publicly sanctioned market regulation in U.S. and Canada, but there are also important differences. The growth of this form of organized intervention in Canadian agriculture in recent years and the apparent continued growth through national marketing boards create a need for a great deal more information than is presently available. This paper summarizes existing legislative sources of producer marketing agencies in Canada and the U.S. as one step toward reducing this information gap.
Les régulations sur la mise en marché sanctionées publiquement aux Etats-Unis et au Canada ont beaucoup de traits communs mais il y a aussi ďimportantes différences. La croissance de cette forme ďintervention organisée dans ľagriculture canadienne au cours des derniéres années ainsi que la croissance apparente engenderée par le Conseil de la mise en marché ont crée un besoin pour beaucoup plus ďinformation qui ne sont actuellement pas disponibles. Cet article réume les sources législatives qui existent présentement dans les agences de mise en marché des produits agricoles au Canada et aux Etats-Unis, comme un pas en avant afin de réduire ce manque ďinformation.  相似文献   
997.
When assessing farming strategies, it is important to account for the opportunities provided for tactically adjusting to outcomes of risk. The hypothesis that accounting for tactical adjustment is more important than accounting for risk attitude was supported in this study with regard to identifying the optimal drainage recirculation strategy for an irrigated dairy farm. Failing to account for tactical adjustment would lead to a sub-optimal choice, costing the farmer about A$3 100 in present value terms. In contrast, failing to account for risk aversion would not affect the strategy chosen. The distribution method was found to be well suited to modelling tactical adjustment.  相似文献   
998.
999.
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   
1000.
This paper illustrates that Canadian Wheat Board (CWB) price pooling provides an important function in western Canada, which is to redistribute returns from the scarce resource of west coast capacity to all western grain producers. The manner in which this distribution occurs has equity implications. A corollary is that the need for prairie wide price pooling by the CWB for distributional considerations diminishes as the west coast export constraint is eliminated. The analysis suggests another conclusion which is that the current set of grains should continue to be exported through only the CWB. Failing that, non-CWB grain exports through the private market should share in the export constraint. Another distributional implication is that reductions in the capacity constraint disadvantages the western livestock industry. Cette étude démontre que l'établissement de la tarification par la Commission canadienne de blé exerce une fonction importante dans l'ouest canadien, qui est de redistribuer les revenues tirés des ressources réduites de la côte du ouest à tous les producteurs de grain dans l'ouest. La manière que cette distribution a lieu a des répercussions en matière d'équité. Un corollaire est que le besoin d'un établissement de la tarification dans les prairies par la Commission canadienne de blé pour des considérations de distribution diminue à mesure que la contrainte d'exportation de la côte de l'ouest est éliminée. L'analyse suggère une autre conclusion selon laquelle les variétés de grains actuelles devraient continuer à être exportées a travers la Commission canadienne de blé seulement. Sinon, les exportations de grains qui ne sont pas visées par la Commission canadienne de blé et que passent à travers le marché privé devraient assumer leur part dans la contrainte d'exportation. Une autre implication sur la distribution est que les réductions dans les contraintes de capacité désavantagent l'industrie d'élevage de l'ouest.  相似文献   
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