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891.
Pascal L. Ghazalian 《Revue canadienne d'agroeconomie》2019,67(1):53-74
This paper examines the magnitudes of border effects on Canada's beef exports, and assesses the prospects for market access. The empirical analysis relies on a gravity model derived from a supply-based framework, and implements different econometric methodologies. It covers the conventional measurement of border effects that is determined relative to the intranational trade baseline. Also, it sets alternative baselines to estimate the wedge between the border effects on beef exports of Canada and those of other countries. The estimated parameters are used to carry out different scenarios to examine the tariff-related and nontariff border effects, and to evaluate the impacts of trade preferences for Canada's bilateral beef exports. The results reveal significant trade impediments facing Canada's bilateral beef exports to many large markets (e.g., EU-15, Japan, Republic of Korea, China, and Russia), and they often indicate that the effects of tariff reductions become considerably larger when coupled with reductions in nontariff impediments. Also, they underscore the significance of North American Free Trade Agreement (NAFTA)’s preferential market access for Canada's beef exports. The export opportunities for the Canadian beef industry that are generated through lower trade barriers would, however, decrease when trade barriers facing other beef-exporting countries are reduced. 相似文献
892.
Food insecurity, child malnutrition, and land degradation remain persistent problems in sub‐Saharan Africa. Agricultural sustainable intensification (SI) has been proposed as a possible solution to simultaneously address these challenges. Yet there is little empirical evidence on if agricultural management practices and inputs that contribute to SI from an environmental standpoint do indeed improve food security or child nutrition. We use three waves of data from the nationally‐representative Tanzania National Panel Survey to analyze the child nutrition effects of rural households’ adoption of farming practices that can contribute to the SI of maize production. We group households into four categories based on their use of three soil fertility management practices on their maize plots: “Nonadoption”; “Intensification” (use of inorganic fertilizer only); “Sustainable” (use of organic fertilizer, maize–legume intercropping, or both); and “SI” (joint use of inorganic fertilizer with organic fertilizer and/or maize–legume intercropping). The results from multinomial endogenous treatment effects models with the Mundlak–Chamberlain device suggest that use of practices in the “SI” category is associated with improvements in children's height‐for‐age and weight‐for‐age z‐scores relative to “Nonadoption,” particularly for children aged 25–59 months. These effects appear to come through improvements in both crop income and productivity. 相似文献
893.
[目的]在推进扶贫攻坚的战略背景下,产业扶贫成为贫困地区脱贫的根本途径,探究特色产业在产业结构调整中扮演的角色及其在扶贫中产生的经济效应,为新时代条件下边境贫困地区精准扶贫模式的优化提供理论支撑。[方法]以新疆边境贫困县阿合奇县为例,将该县的GDP、农牧民人均纯收入、财政收入、社会消费品零售总额、三大产业产值作为变量指标,通过构建灰色关联模型,分析研究当地的沙棘产业扶贫所产生的经济效应。[结果]阿合奇县沙棘产值与GDP、农牧民人均纯收入、财政收入、社会消费品零售总额的关联度分别为0581、0708、0659、0622; 沙棘产值与一、二、三产业的关联度分别为0614、0742、0640。[结论]特色产业扶贫要锁定优势特色产业,精准定位沙棘产业发展方向,建设沙棘产业品牌,充分发挥沙棘产业的带动作用,强化沙棘产业与第三产业的联系,优化沙棘产业布局,完善各方利益联结机制,进一步强化特色产业与贫困人口的联系。 相似文献
894.
黄土高原土地利用变化特征及其环境效应 总被引:3,自引:0,他引:3
研究目的:基于黄土高原近30余年来土地利用/植被覆盖变化(LUCC),分析该地区LUCC及其环境效应,为区域生态环境与社会经济的可持续发展政策提供科学依据。研究方法:地统计和趋势分析等。研究结果:(1)黄土高原土地利用结构整体上未发生变化,仍以草地、耕地和林地为主,但植被覆盖度提升显著;(2)黄土高原LUCC受气候变化和人类活动共同影响,影响程度存在区域性差异,其中黄土高原中部丘陵沟壑区主要由人类活动导致;(3)黄土高原LUCC对地表径流、土壤侵蚀、土壤水分及碳循环等生态环境过程将产生长期的影响,植被恢复在发挥生态效益的同时对区域生态环境产生消极的作用。研究结论:黄土高原植被生产力已接近水资源承载力阈值,提升人工植被稳定性、促进水资源平衡仍为现阶段促进黄土高原可持续发展的主要课题。 相似文献
895.
We test the ‘efficient-but-poor’ hypothesis by estimating the determinants of smallholders' choice over cash or food crops and whether their crop choice affects technical efficiency and poverty using the national household panel data in Nigeria. We employ the stochastic frontier analyses correcting for sample selection about farmers' crop choice. Our results indicate that smallholders are generally efficient in their resource allocations. A treatment effects model is employed to estimate farmers' crop choice in the first stage and the impact of their choices on technical efficiency and poverty outcomes in the second stage. The results show that farmers' access to free inputs, non-farm income and the use of seeds from the previous growing season are important determinants of crop choice. The adoption of cash crops by food-crop producing households will not generally reduce poverty, although it will improve technical efficiency marginally. However, if cash crops are commercialised, poverty tends to decline. 相似文献
896.
We explore the effects of different farmer organisations on smallholder farmers' economic performance. The average treatment effect of switching between different farmer organisations is examined. In addition, based on the premise that a higher level of social capital is accumulated through participation in multiple farmer organisations, we also investigate how the economic consequences of farmer organisation membership vary with the intensity of participation. Our conceptual model explicitly includes social capital to provide a micro-foundation and a theoretical justification for the linkage between farmer organisation participation and the economic outcome. This indicates that participating in different types of farmer organisations is beneficial for farm households only when the returns from social capital investment outweigh the time cost of participation. Our empirical results suggest that membership of farmer organisations that are more homogeneous in terms of member specialty and similarity in production and marketing activities results in a significant increase in farm sales revenue and net returns. This result supports the view that technological proximity accentuates knowledge spillovers within the farmer organisations, and thus leads to better economic outcomes. In line with the prediction of the theoretical model, the average treatment effect of participation is found to increase with the number of organisations that farmers belong to. Moreover, results from the quantile regression provide empirical evidence supporting increasing returns to social capital accumulated through participation in several farmer organisations. 相似文献
897.
Does mixed crop‐livestock farming lead to less diversified diets among smallholders? Evidence from Laos 下载免费PDF全文
Priyanka Parvathi 《Agricultural Economics》2018,49(4):497-509
Malnourishment continues to remain a challenge in developing countries. As the undernourished are largely smallholder farmers, it is widely assumed that farm diversification and mixed crop‐livestock agricultural systems can help alleviate this problem. However, empirical evidence in this context is limited. Hence, we use a two‐year panel's data from Laos to examine whether farm production diversity as well as a mixed crop‐livestock farming system improves household dietary diversity among smallholder farmer. The results from the fixed effects regression indicate that although farm production diversity does lead to a higher dietary diversity, the effect diminishes with continued farm diversification. The counterfactual analysis from the endogenous switching regression reveals that mixed crop‐livestock farming systems do not necessarily enhance dietary diversity. However, we further find that purchasing food from the markets plays an important role in enhancing the dietary diversity of rural smallholder farmers. 相似文献
898.
This study evaluates how landscape changes made in order to improve the visual quality of olive groves may trigger first and second-order effects (FOEs and SOEs) on the rural economy. The choice experiment method is combined with the probability of visiting to estimate the marginal increase in recreational demand derived from the combination of three landscape elements: green cover, stone walls and woodland islets. The results suggest that the improvement of the aesthetic value of landscape (mainly through green covers and stone walls) creates a real, positive asset (due to its FOEs and SOEs) for the local economies in rural areas. The promotion of the recreational value of these areas to attract more visitors and so bring in more income could be a profitable policy, which could be implemented by hybridizing the current Agri-environmental scheme with a Payment for Ecosystem Services approach. 相似文献
899.
A detailed understanding of multiple human and environmental factors influencing land allocations among agricultural uses can facilitate more efficient and targeted land policy. To show this, we used a comprehensive dataset of socioeconomic, physiographic, and climatic indicators to investigate potential determinants of land-use in Australia’s intensive agricultural region during the period 1992–2010. We applied a seemingly unrelated regressions land-use shares spatial error model with random effects coupled with variance decomposition analysis to identify the statistical significance, direction and magnitude of observed associations between land-use and its drivers.Population: density, rainfall, equity ratio, and access to markets were the most influential policy-relevant land-use factors. Land allocations to cereals and livestock production were significantly influenced by spatiotemporal rainfall and temperature variability. Improved pastures, cereals, annual and perennial crops plantations were larger in regions with better access to markets. Increases in equity ratio (i.e., better financial position) were associated with larger land allocations to improved pastures and annual crops and smaller extensive grazing area. Marginal associations were detected between land-use and output prices, and higher population density was associated with lower shares for all high value agricultural land-uses. The results suggest that improved transportation infrastructure, zoning regulations, and mechanisms to reduce farm debt exposure and risks from climate variability could have significant impact on the configuration of the Australian agricultural landscape. 相似文献
900.
Green Bio-Refineries (GBRs) have economic and environmental potentials through changing land use from cereals to grass production and provision of grass-based protein feed for livestock production and other valuable byproducts. However, the potentials are dependent on local conditions of the GBRs, such as land productivity, environmental sensitivity and transport distances for feedstock as well as the regional economy which GBRs are a part of. In this paper, we compare the total (direct, indirect and induced) effects of different location choices of GBRs in Denmark at different (municipal, regional, national) scales − a key step for decisions about development of GBRs from both investors' and authorities' perspectives. We integrate a local life-cycle assessment (LCA), a geographic information system (GIS) analysis and an economic-environmental input-output (EEIO) based model (LINE) into a common framework (GIS-LCA-EEIO). We show that locating GBRs in Western Denmark, where the soils are primarily sandy and livestock densities are high, generates higher socio-economic gains than in Eastern Denmark, where the soils are primarily loamy and the concentrations of livestock are lower. We conclude by sketching out priority areas for developing GBRs and discuss the policy implications of the results within the context of development of a bio-based economy. 相似文献