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951.
In the last decade special attention has been focused on estimating a firm’s efficiency and productivity; Stochastic Frontier Analysis (SFA) has been one of the most used techniques that allows the separation of inefficiency from stochastic noise, assuming homogeneous technology is available to all producers and that there is independence between observations. However, this second assumption is violated data are spatial auto-correlated, thus biasing statistical inference. Attention has, therefore, shifted to models that allow the controlling of heterogeneity introducing, in the model or in the error term, contextual variables correlated with inefficiency. In our paper we propose viewing the spatial external factors (natural or artificial) in a new way: instead of identifying ex-ante a multitude of determinants, often statistically and economically difficult to detect, we suggested using an original methodology that, following a classical SFA approach, splits efficiency into three components: the first one is linked to the spatial lag, the second one to the DMU’s specificities, and the third to the error term. Finally, we tested our method using simulated data and examined the Italian wine sector, testing the ability to control spatial, global and local heterogeneity. 相似文献
952.
Charles Weiss William B. Bonvillian 《Technology Analysis & Strategic Management》2013,25(10):1189-1208
The US national innovation system has a dual structure: part suited to rapid innovation, and part stubbornly resistant to change. The complex, established ‘Legacy sectors’ that resist change, particularly disruptive innovation, share common features that obstruct the market launch of innovations, over and above the ‘valley of death’ and other obstacles that have been the traditional focus of innovation policy. Innovations in Legacy sectors must penetrate a well-established and well-defended technological/economic/political/social paradigm that favours existing technology, characterised by (1) ‘perverse’ subsidies and price structures that create a mismatch between the incentives of producers and broader social goals, such as environmental sustainability, public health and safety, and geopolitical security; (2) established infrastructure and institutional architecture that imposes regulatory hurdles or other disadvantages to new entrants (3) market imperfections beyond those faced by other innovations: network economies, lumpiness, economies of scale, split incentives, needs for collective action, and transaction costs (4) politically powerful vested interests, reinforced by public support, that defend the paradigm and resist innovations that threaten their business models (5) public habits and expectations attuned to existing technology and (6) an established knowledge and human resources structure adapted to its needs. Beyond these obstacles, more socially desirable technologies that are driven by environmental or other non-market considerations must overcome the lack of agreed replacement standards against which putative alternatives can be judged. We have developed a new, integrative analytic framework for categorising the obstacles to market launch faced by Legacy sectors, and earlier applied this method to energy, health delivery, the long-distance electric grid, building, and air transport. In energy especially, the requirement for innovation is sufficiently urgent that large-scale domestic and collaborative international research should take place even at the cost of possible competitive disadvantage and even if it is some time before the USA adopts carbon charges and thereby puts pressure on the prevailing paradigm of fossil fuel use. We now extend this method to sustainable agriculture. American paradigms in agriculture and in energy are exported worldwide, delaying the development and spread of needed innovations that are not consistent with them. Foreign manufacturers wishing to enter US markets must suit their products in these sectors to American paradigms, while American exports of technology may be insufficiently cost conscious or respectful of environmental sustainability. Developing countries are technology takers and suffer from asymmetric innovative capability. They need to choose sources of technology best suited to their situation. India and China constitute new competitive threats, but also represent ‘innovative developing countries’ that have large domestic markets in which they are launching innovations aimed at their lower income populations. 相似文献
953.
在今后一定时期,发展现代化大农业是黑龙江省农业和农村经济发展的主题和战略任务。现代化大农业首先是现代农业,其次是具有“大”字特征的现代农业,其中“大规模”是发展现代化大农业的物质基础,“大组织”是其经营主体,“大农机”是生产工具,“大科技”是生产手段,“大服务”是保障体系,“大市场”是支撑条件,“大产业”是实现形式和发展理念,“大产出”是发展目标和必然结果。 相似文献
954.
955.
The East Usambaras in Tanzania are a tropical biodiversity hotspot where current agricultural management practices pose threats to forest conservation and development objectives. Promoting sustainable agricultural intensification (SAI) would improve long-term productivity and reduce pressure on forest reserves. The study objective was to identify household-level characteristics that influence adoption of improved management practices, specifically soil replenishment practices, in order to identify opportunities and constraints to scaling up SAI to landscape level. First, three common farming systems and a fourth agroforestry (AF) model were developed to estimate the relative profitability of incorporating fallow, manure, and non-timber forest product activities. Next, household surveys were conducted and a logistic regression analysis was used to measure the influence of socioeconomic characteristics, physical and financial assets, tenure security, and plot-specific attributes on adoption of soil replenishment practices that were specified in the model. Findings showed that the AF model was financially competitive but raises opportunity costs to labour when compared to common systems. Marital status, household size, remittances, credit access, and tenure security significantly influenced adoption of fallow and applying organic inputs. Significant plot-specific attributes included perceived fertility and distance from the homestead. Policies to scale up SAI should consider these factors and emphasize improving markets for AF species and extension services. 相似文献
956.
Today, less than 3% of the 250,000 plant varieties available to agriculture are in use. Sources of (agricultural) biodiversity are under threat and disappearing in many regions. Increasing industrialisation of agriculture and top-down agricultural research have contributed to this dependence on a relatively few plant varieties. This article argues that new approaches to agricultural development research are needed to conserve agricultural diversity, improve crops, and produce food of quality for all. Such an approach should enable small farmers on marginal lands to participate as equal partners alongside agricultural scientists, fairly sharing their know-how, expertise and seeds. Three case studies illustrate how farmers and plant breeders are working together in a diversity of agro-ecological, socio-economic and political contexts to put these new approaches into practice. New forms of collaboration are producing an increase in diversity and a number of promising improved varieties in terms of yields, agronomic traits and taste. These varieties are showing better adaptation to the local environmental conditions without requiring extra external inputs. Long-term success requires that these efforts be backed up by supportive policies, by actions to ensure that policies are implemented, and where necessary by related legislation. 相似文献
957.
Yildiz Atasoy 《Journal of Agrarian Change》2013,13(4):547-570
This paper examines the shifting relations of food provisioning in Turkey as small producers are increasingly integrated into commercialized agri‐food supply chains led by supermarkets. Turkey's entry into a customs union with the European Union and a World Bank–imposed policy measure adopted during the 2001 economic crisis have greatly facilitated the process of market intensification in Turkish agriculture. There are two sides to this process: one concerns the historical centrality of small‐scale production directed towards local–regional consumers; the other relates to the dominant role played by supermarkets in changing the conditions of subsistence. The restructuring of wholesale markets and the privatization of formerly state‐led agricultural co‐operatives and producers' unions have been crucial for the expansion of supermarkets into agri‐food relationships. The competitive growth of Islamically oriented small and medium‐sized capital groups alongside large retailers is further deepening the commodification process in food relationships. 相似文献
958.
Cotton farmers in many developing countries are facing decreasing marginal returns due to stagnating yields and high input costs. Conversion to organic management could offer an alternative. In a two year comparative study in central India covering 170 cotton fields, organic farms achieved cotton yields that were on par with those in conventional farms, whereby nutrient inputs and input costs per crop unit were reduced by half. Due to 10–20% lower total production costs and a 20% organic price premium, average gross margins from organic cotton fields were 30–40% higher than in the conventional system. Although the crops grown in rotation with cotton were sold without premium, organic farms achieved 10–20% higher incomes from agriculture. In addition to these economic benefits, the organic farming system does not burden soil and groundwater with synthetic fertilizers and pesticides. However, in this study only minor differences were detected in soil fertility parameters of organic and conventional fields. Altogether, the results suggest that conversion to organic farming can improve livelihoods of smallholders while protecting natural resources. Income loss due to reduced yields in initial years of transition, however, constitutes a major hurdle, especially for poorer farmers. It is thus important to support farmers in overcoming the obstacles of the conversion period. 相似文献
959.
Participatory approaches have emerged in developing countries as an integrated and holistic system approach for assessing the agro-ecosystem sustainability. The aim is to integrate and apply knowledge about natural and social aspects of agro-ecosystems, taking into account their long-term, uncertain and non-linear relationships. The purpose of the study described in this paper was to assess the sustainability of the agro-ecosystem of Abesard in Tehran Province. A participatory landscape/lifescape appraisal (PLLA) method was used within an agro-ecological framework to assess the farmers’ sense of agricultural sustainability based on different categories of sustainability (better-off, average and poor). Results indicated that a majority of farmers think of sustainability solely as an economic issue, followed by sustainability being a combination of ecological and social concerns. Regarding the indicators of sustainability, results revealed that for farmers in the poor group, resilience and stability were critical criteria, whereas for better-off farmers, stability, reliability and resilience were generally important. However, the average group of the farmers was placed between the two groups. Overall, it was concluded that the economic status of households has an influence on the sustainability of their agro-ecosystems and that improvement of their economic situation promotes agricultural sustainability. It could also be concluded that PLLA has the potential to integrate socio-economic (lifescape) and environmental (landscape) dimensions for analysing the sustainability of agro-ecosystems. 相似文献
960.
The growth of China's middle class is driving an expansion of interest in ‘green’ and sustainable food, food that is perceived to be healthy, safe and environmentally friendly. Self-consciously ‘sustainable’ agriculture is a new phenomenon in China, but it has emerged from, and builds upon, an agrarian history that is markedly different from that of the West. In this paper, we address the relationship between the Chinese middle class, an overwhelmingly urban group, and Chinese sustainable agriculture, a largely urban-oriented enterprise, from the perspective of our work in establishing and operating Beijing's first Community Supported Agriculture (CSA) farm. We discuss the farm's environmental and institutional sustainability, situating its development within the larger context of contemporary Chinese agriculture, and we examine the potential for future success with CSA models in China based on evidence from this case. 相似文献