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41.
This study develops and estimates a dynamic multi‐output model of farmers’ land allocation decisions that allows for the gradual adjustment of allocations that can result from crop rotation practices and quasi‐fixed capital constraints. Estimation is based on micro‐panel data from Danish farmers that include acreage, output, and variable input utilization at the crop level. Results indicate that there are substantial differences between the short‐run and long‐run land allocation behaviour of Danish farmers and that there are substantial differences in the time lags associated with different crops. To our knowledge, this is the first dynamic micro‐model of land allocation estimated on data from the temperate climate zone. Since similar farming conditions are found in northern Europe and parts of the United States and Canada, this result may be of wider interest.  相似文献   
42.
This study aimed at examining the merit of crop diversification as a strategy for agricultural growth in Bangladesh. Specifically, the existence of economies of diversification, scale economies and diversification efficiencies at the farm level were examined using a stochastic input-distance function approach. The results reveal strong evidence of diversification economies amongst most crop enterprises except the combination of modern rice and modern wheat enterprises. Ray economies of scale exist in Bangladeshi cropping system. Also, significant are efficiency gains made from diversification among cropping enterprises. The key policy implication is that crop diversification should be a desired strategy for agricultural growth in Bangladesh. Development of the rural infrastructure is also essential as this will not only improve technical efficiency but may also synergistically promote crop diversification by opening up opportunities for technology diffusion, marketing, storage and resource supplies.  相似文献   
43.
吴丹 《国际贸易问题》2008,305(5):32-36
本文利用东亚10个主要经济体1995-2004年的面板数据,建立东亚贸易引力模型,对东亚进口贸易流量的影响因素和潜力进行研究。研究显示,国家经济规模、中国-东盟自由贸易区、东盟自由贸易区、进口国制度、国际直接投资、国家间的经济水平差距和地理距离是东亚双边进口贸易流量的主要影响因素。中国香港、泰国、日本和印度尼西亚对东亚的进口潜力较大,中国、马来西亚、菲律宾和新加坡对东亚的进口潜力较小。加强东亚区域内最终产品市场和区域贸易合作的发展、推进东亚各经济体的制度改革和调整、积极合理地引进国际直接投资、加强物流建设与合作,应成为东亚各经济体未来重要的政策取向。  相似文献   
44.
The European political framework of the last decade aims to drive agriculture towards economic and environmental sustainability. Thus, European institutions have paid great attention to environmental impact assessment and to the definition of a complex indicator capable of restoring the multidimensional nature of environmental sustainability.In this work, a possible methodology for assessing the environmental sustainability of European national cropping systems by a synthetic indicator is provided. More specifically, the environmental impact of agriculture is assessed through a synthetic indicator, whose definition is based on a methodological improvement of the ecological footprint approach, which quantifies the balance between exploitation and availability of natural resources used in agriculture.The analysis shows how national cropping systems can contribute to Europe’s environmental impact through agriculture. To assess an eventual relationship between agriculture’s environmental performance and the ability to support more sustainable agriculture at the national level, the results are then compared with the subsidies for agro-environmental measures provided by the second pillar of the CAP. In addition, the synthetic indicator chosen for the study, giving the possibility of quantifying the dynamic of the environmental impact of agriculture between two different periods, permits the analysis of the possible causes that may have generated the observed changes.The implications of this approach should stimulate new reflections on the significance of the ecological relationships embodied into agricultural production and the environmental role of farmers.  相似文献   
45.
Agricultural land use is increasingly changing due to different anthropogenic activities. A combination of economic, socio-political, and cultural factors exerts a direct impact on agricultural changes. This study aims to illustrate how stakeholders and policymakers can take advantage of a web-based spatial decision support system (SDSS), namely SmartScape™ to either test existing crop change policies or produce effective crop change decisions using tradeoff analysis. We addressed the consequences of two common crop change scenarios for Dane county in Wisconsin, United States, (a) replacing perennial energy crops with annual energy crops and (b) replacing annual energy crops with perennial energy crops. The results suggested that converting areas under grass and alfalfa production that were located on high quality soil and flat slope to corn promoted a net-income and availability of gross biofuel. Additionally, the model outcome proposed that converting areas under corn and soy production that were located on high slope to grass promoted net-energy, phosphorus loading, soil loss, soil carbon sequestration, nitrous oxide emission, grassland bird habitat, pollinator abundance, and biocontrol. Therefore, SmartScape™ can assist strategic crop change policy by comparing the tradeoff among ecosystem services to ensure that crop change policies have outcomes that are agreeable to a diversity of policymakers.  相似文献   
46.
This study is a sequel to one providing a methodological framework for evaluating the economic and soil-erosion effects associated with different crop rotational systems involving corn on southern Ontario cash-cropping farms. A multi-period linear programming (MPLP) model is used to estimate the impact on rational crop rotational choices, fam-level profitability and soil-erosion rates of having different values for the more important economic variables. The variables examined are relative cash-crop prices, fossil fuel energy-related production costs, discount rates, and values attached to soil lost through erosion. The MPLP model is solved in turn for each of a range of values for one of the economic variables at a time, the selection of values being based upon recent historical experience. Where no change in rotational system is prompted within the range, the MPLP model is used to find the value of each economic variable that would be required to trigger the choice of some alternative rotational system. Each of these model runs is performed for the case where yields of all crops over a 20-year time horizon are firstly assumed constant, and secondly assumed to suffer a cumulative decline. Cet article fait suite à une étude méthodologique dont le but a été d'valuer les effets économiques et érosifs de systémes de production produisant essentiellement du maïs en rotation avec d'autres cultures. Cette méthode d'analyse est appliquée à des exploitations agricoles localisées dans le Sud de I'Ontario et specialisées dans les cultures commerciales. Pour ce faire, un modéle linéaire multi-période (MPLP) est utilisé pour estimer I'impact d'un changement dans les principales variables économiques sur le choix des rotations culturales, le niveau de rentabilité des systémes de production et les taux d'érosion des sols. Les variables économiques prises en compte sont les prix relatifs des cultures commerciales, les coûts de production associés à la consommation d'énergie fossile, les taux d'actualisation et les pertes absolues en sol dues à l'érosion. Le modéle linéaire (MPLP) est de nouveaurésolu pour chaque variable économique en les paramétrisant sur un intervalle de valeurs selectionnées à partir de donntes historiques récentes. Lorsqu'il n'y a aucun changement dans la rotation culturale, le modéle détermine le niveau de chaque variable qui entrainerait la prise en considération d'une rotation culturale alternative. Toutes les simulations ont été effectuées sur une période de vingt ans en adoptant deux variantes sur I'tvolution des ren-dements des cultures commerciales: premierèment, les rendements restent constants durant toute la période, et deuxiémement, les rendements décroissent de maniére cumulative.  相似文献   
47.
We hypothesize that institutions such as agricultural cooperatives influence regional levels of variety diversity through input supply, processing or marketing functions. This diversity can also affect yield, a partial measure of crop productivity. We test these hypotheses with data from southern Italy, a mega-diversity spot and centre of diversity for durum wheat. Cooperatives in the southern regions of Italy process farmers’ harvests of durum wheat into bread, label it, and sell it locally. In this relatively marginalized region of the country, cooperatives enable farmers to capture more of the value of the final product and reduce marketing costs. To test the hypothesis, we apply a two-stage estimation approach with a Cobb-Douglas production function and panel data analysis. Findings suggest that the density of cooperatives in a region is associated with greater spatial diversity in wheat varieties grown, and that, over a 14-year period, this diversity positively affected crop yields.  相似文献   
48.
农业保险需求问题的一个理论研究及实证分析   总被引:21,自引:0,他引:21  
本文对农业保险的需求从三个层面进行了经济分析,并运用田野调查的方法进行了实证研究。发现中国农业保险需求不旺盛的原因,主要源于农业自然风险在影响农户正常生活的各种因素中并不显著等因素。因而,在农村开展商业性农业保险的时机并不成熟。但是,在规模较大的自然灾害风险条件下,农业保险可以补充农民利用传统风险分散的能力,有助于迅速恢复再生产,因此,政策性农业保险在农业生产过程中,能够起到一定的作用。  相似文献   
49.
The current study seeks to assess the private benefits associated with multiple soil conservation practices (MSCPs) by estimating the marginal value of crop production that can be attributed to such practices. In areas where land degradation associated with soil erosion causes serious agri-environmental challenges such as loss of soil fertility, siltation and eutrophication, a multiple approach to soil conservation is neccessary. However, notwithstanding efforts to encourage adoption of such practices, their uptake remains generally low. Analysing the effect of MSCPs on crop productivity is one of the ways through which the incentives for soil conservation can be explored. To achieve the stated objective, the current study applied propensity score matching and exogenous switching regression techniques to cross-sectional data collected from a random sample of farm households located in Lake Naivasha basin, Kenya. Results indicate that there is a significant positive effect of implementing multiple soil conservation practices on crop productivity. However, we note that whether the additional benefits will cover the opportunity costs associated with the implementation of these practices will depend on farm specific attributes such as slope and the soil conservation effort. In cases where marginal benefits are not substantial to cover opportunity costs for implementation of soil conservation practices, intrinsic or external incentives could be necessary. Policy interventions could focus on offering technical assistance to farmers in selecting soil conservation practices that are best suited to their local condition.  相似文献   
50.
Building resilience is critical for metropolitan land use planning to strengthen the ability to cope with and minimize climatic disaster risks. Challenges still remain for metropolitan agencies in identifying the components or metrics for measuring resilience. Particularly, uncertainties in climate change and diversification in local contexts compel urban planners to mainstream community participation, indigenous knowledge and local attributes into the resilience assessment. This article aims to propose a novel methodology for assessing resilience, which can encourage stakeholder participation and communicate planners in shaping metropolitan land use policies. Using the Taichung metropolis, Taiwan as the study area, this article created a resilience metric called the Climatic Hazard Resilience Indicators for Localities (CHRIL) that is appropriate for use in a policy context. Then, this metric combined a fuzzy multicriteria decision analysis with a participatory geographic information system approach to measure and map resilience to climatic hazards. Through the participation of experts, local officers and community members, a multivariate analysis was applied to explain why low resilience areas occur in specific locations. Moreover, we performed a cluster analysis to group the areas into several types of resilience and revealed the relationship between the resilience factors and overall local development patterns. Results show that conflicts and tradeoffs may exist between some resilience factors, especially socioeconomic vulnerability and adaptive capacity. The findings provide stakeholders and policy-makers with a better governance structure to design and synthesize appropriate patchworks of planning measures for different types of resilience areas to reduce climatic hazard risks.  相似文献   
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