The resilience of long and short food chains: a case study of flooding in Queensland,Australia

This paper provides new insights into the food security performance of long and short food chains, through an analysis of the resilience of such chains during the severe weather events that occurred in the Australian State of Queensland in early 2011. Widespread flooding cut roads and highways, isolated towns, and resulted in the deaths of people and animals. Farmlands were inundated and there were food shortages in many towns. We found clear evidence that the supermarket-based (long) food chain delivery system experienced significant difficulties in supplying food to flood-affected towns. In contrast, more localized (short) food supply chains—which relied upon supply from growers in peri-urban areas and community-based food initiatives—remained largely intact, and provided food at a time when the supermarkets were limited in their ability to respond to consumer demand. However, on closer examination of food distribution during flooding in the regional city of Rockhampton and in the State capital, Brisbane, the demarcation of success between “long” and “short” food chains became blurred. Both types of food supply chains shared some key resilience characteristics in responding to crisis but diverged in other important ways. We argue that conceptualizing food chains in terms of key elements of resilience—scale, diversity, flexibility and cohesion—may be more fruitful than the short-long dichotomy alone. This approach is particularly useful when prioritizing food security as the basis for evaluating food system sustainability in a context of predicted increases in extreme weather events and future climate change.     

美国食品上市公司召回启动时间影响因素的实证分析

为探究食品召回启动时间的多重影响因素问题,以1994—2017年美国食品上市公司发生的召回事件为研究样本,构建多元线性回归模型,实证分析食品召回启动时间的影响因素。结果表明:召回启动时间的主要影响因素有召回量、分销范围和召回原因(细菌感染和外来物质污染);召回量对召回启动时间具有显著的正向影响;分销范围越小,召回启动时间越短;召回原因为细菌感染或外来物质污染时,召回启动时间相对更短;召回主体对召回启动时间没有表现出显著影响。本研究为完善我国食品召回体系,从公司、供应链和政府层面提出强化食品HACCP认证、完善食品安全溯源监管系统、建立专项储备基金制度等对策建议。     

Food access and pro-poor value chains: a community case study in the central highlands of Peru

Pro-poor value chains intend to integrate smallholding farmers into high value markets to contribute to poverty alleviation and food security. Although income benefits of pro-poor value chains have been found, scant evidence exists regarding the potential for these markets to enhance food security. This study focuses on components of food access—dietary diversity, physical and financial access, and social acceptability—among households that participate in pro-poor value chains and non-participating households in the central highlands of Peru where development interventions have created high value market niches for the native potato varieties that smallholding farmers have conserved for thousands of years. Using a mixed methods approach, this study assessed dietary diversity among households that participate and do not participate in pro-poor value chains, as well as their perceptions of their food access. Findings indicated that households that participate in value chains have higher dietary diversity than non-participating households but that these differences are likely due to pre-existing differences in socioeconomic status rather than any causal effect provided by value chains. The study also concluded that while participation in pro-poor value chains sometimes enhance the purchasing power of participating households, they may also weaken financial access, important for both purchasing food and travel to make those purchases. Community perspectives also indicated concerns with the acceptability of diets, which cannot likely be comprehensively addressed by pro-poor value chains. Collectively, the findings from this study cast doubt on the assumption that a linear flow exists between pro-poor value chains and enhanced food access.     

Private standards, grower networks, and power in a food supply system

The role of private food standards in agriculture is increasingly raising questions of legitimacy, particularly in light of the impacts such standards may have on food producers. While much work has been carried out at a macro policy level for developing countries, there have been relatively few empirical case studies that focus on particular food supply chains, and even fewer studies still of the impact of private standards on developed countries such as Australia. This study seeks to address this imbalance, with a particular focus on examining the impact of private standards on an Australian vegetable supply food system in North Tasmania as well as tracing the impact of perceived and actual power relations among actors. Applying a governance framework and adopting a Foucauldian position we show that private standards are a “technology of power” that have risen out of a crisis discourse in the mid-1990s about on-farm food safety. Private standards have the effect of using knowledge from particular actors to establish truths about good agricultural practice (GAP), however we show that Tasmanian vegetable growers are not docile bodies and are employing alternative knowledge and technologies of power to challenge how GAP is implemented on-farm.     

Financialization in agri-food supply chains: private equity and the transformation of the retail sector

The analysis of the financialization of food and farming has tended to focus on issues such as the impact on the productive and input sectors of the food chain, including the role of asset management companies, private equity consortia and other financial institutions in acquiring and managing farmland. However, processes of financialization impact along the whole agri-food supply chain, including the retail and food service sectors. This paper analyses the take-over by a private equity company of Somerfield, one of the UK’s leading supermarket chains, and the impact the subsequent restructuring had on the management and organization of the retailer’s operations. In doing so, the paper not only extends the analysis of the effects of financialization on the food system, but also raises questions about the extent to which the supermarkets are the dominant actors in the establishment and management of agri-food supply chains.     

山东省粮食产量连续十年增长的保障因素分析

1978年至2012年山东省粮食产量数据显示出明显的“三阶段”波动特征。借助主成分分析与岭回归的方法,对不同阶段影响山东省粮食产量的主要因素进行实证检验,结果显示,近阶段山东省粮食产量连续10年增长的主导因素是农业生产条件的持续改善,主要包括农机总动力、有效灌溉面积、化肥使用折纯量、农村用电量及支农支出的有效保障。但同时也存在化肥使用量增速过快、复种指数偏低等制约因素,会在一定程度上降低粮食持续增产的可能性。加强水利建设、保证复种指数、提高补贴力度等可以作为进一步保证粮食安全、促进粮食增产的措施。     

Impact of the COVID-19 pandemic on agricultural exports

The COVID-19 outbreak has shocked the world's economies in the year of 2020. As this pandemic spreads around the globe, many experts feared that the global food supplies might start running short, especially if supply chains were disrupted. COVID-19 also added to the uncertainty of the business operation. Therefore, it is critical to understand how COVID-19 pandemic affected global food supply and market. In this study, we investigate the impact of COVID-19 on agricultural export companies in China using a unique firm-level survey data. We found that although on average agricultural businesses experienced declines in the exports, exports of some agricultural products especially grain and oil held strong and even increased, implying the essential demand for staple food during the pandemic. Not surprisingly, exports of medicinal herb also increased significantly during the pandemic. However, exports of goods such as edible fungus and horticultural products sharply decreased. Our results also showed that in general, impact of COVID-19 on smaller firms was more severe than that on larger firms. The results of this study can provide useful guidance and implications for agricultural businesses and policy makers on their COVID-19 mitigation efforts to navigate this global pandemic.     

Information services for European pork chains - Closing gaps in information infrastructures

Several global developments (e.g. diminishing production resources, growing demand for bio-energy) and numerous sector-wide crises (e.g. BSE, swine fever, dioxin) have led to a changing attitude of society towards the consequences of the food systems activities for social, economic and environmental issues, captured in the term of sustainability. Consumers in their role as final customers, and as a consequence also enterprises within agri-food supply chains, show increasing interest in the characteristics of food, and in turn, on the availability of related information and guarantees. Enterprises in agri-food supply chains are facing new expectations and are seeking to communicate social, economic and environmental performance of their business to customers within their supply chain and to consumers. New solutions for determination and communication of sustainability are needed for the agri-food sector, covering single aspects of sustainability as well as sustainability in a broader sense, including social, economic and environmental issues. Integrated, computer-based information services, since they are mainly building on existing systems, provide flexible solutions for enterprises to measure and evaluate sustainability of products throughout agri-food supply chains. Gained information on product characteristics might be used for decision support within enterprises as well as for communication of sustainable practices to customers and consumers, resulting in increased competitiveness of enterprises, supply chains and the sector by satisfying customers’ and consumers’ demands for information on the sustainability of a product. The present paper introduces a framework for developing information services for European pork chains using the three selected information domains food safety (representing social sustainability), quality (representing economic sustainability) and global warming potential (representing environmental sustainability). Resulting information models give an aggregated overview on information availability and exchange in European pork chains, additional information demands of possible service users and deficiencies in the existing information infrastructures. The paper supports different stakeholders involved in agri-food production, such as service developers, enterprise decision makers and management consultants, in developing enterprise- and chain-specific solutions which meet customers’ and consumers’ demands by providing appropriate sustainability information and guarantees.     

Ring closure of carbon nanotubes

Lightly etched single-walled carbon nanotubes are chemically reacted to form rings. The rings appear to be fully closed as opposed to open coils, as ring-opening reactions did not change the structure of the observed rings. The average diameter of the rings was 540 nanometers with a narrow size distribution. The nanotubes in solution were modeled as wormlike polymer chains, yielding a persistence length of 800 nanometers. Nanotubes shorter than this length behave stiffly and stay nearly straight in solution. However, nanotubes longer than the Kuhn segment length of 1600 nanometers undergo considerable thermal fluctuation, suggesting a greater flexibility of these materials than is generally assumed.     

Poverty reduction through the development of inclusive food value chains

Propelled by urbanization, rising incomes, and changing diets, food markets have been expanding in Africa and South Asia, creating the vast potential for job and income opportunities along food supply chains and, hence, for poverty reduction. The novel coronavirus(COVID-19) that spread to a pandemic in early 2020 provokes enormous setbacks to this expansion. This, however, should provide lessons regarding the importance of resilient and inclusive food systems. Emergency responses to COVID-19 should consider interventions towards that end and leverage the opportunities provided by food markets growth as economies recover from the present economic recession. This paper assesses options of how this could be done by facilitating the better functioning and interconnectedness of the many small and medium-sized enterprises that are proliferating along the "hidden middle" of food value chains in storage, logistics, transportation, and wholesale and retail distribution. It also explores how policies can help smallholder farmers connect to this "hidden middle" in more gainful ways and help them climb out of poverty as well.     

India: a perspective on the food situation

Four major points emerge from this brief survey of the evidence: 1) The food crisis in 1974 seems to have been largely a result of distributional factors. The per capita availability of food grains from all sources, including imports, although below 1971 and 1972 levels, was probably above the average for 1963 to 1973. Comparison of available food supplies with estimated caloric and protein requirements of the population indicates that, on average, enough food was available to meet minimal requirements, with a small margin to spare. Supplies obtained through the government procurement and distribution program were especially short since the program depends primarily on the winter harvest, which failed badly in 1974. Thus, urban areas and some pockets of rural areas were badly hit. The poorest third of the population, who receive 20 to 30 percent less food than the national average even in normal times, were severely affected by higher prices, and there is little doubt that a sizable fraction of the population received inadequate diets. 2) The food supply for 1975 depends heavily on the winter harvest. If this is good, as it promises to be, widespread starvation, but not hunger, should be averted. Since the main shortfall was in the summer crop, the nature of the distribution problem will be different and shortages may be spread more evenly over the population. Nevertheless, the situation seems to forebode considerable hardship for the poorer segments of the population. 3) Food requirements will continue to grow over the foreseeable future as a result of rising population and incomes. India's agricultural resources are still relatively poorly exploited. In the short run, output can probably be increased substantially by increased fertilizer use on traditional as well as new varieties. In the longer run, increased production can be obtained from more intensive cropping, expansion of surface and groundwater irrigation, improved water management, and improved cultural practices brought about by more active agricultural research and appropriate land and pricing policies. These measures will need buttressing by an expanded food storage program if extreme hardships due to periodic drought are to be avoided. 4) India's farmers have shown considerable willingness to innovate under favorable conditions. The rate of adoption of HYV's in the first few years after their introduction was impressive. The same was true for tubewells and fertilizers. Nevertheless, many of the easy gains may already have been made. Fragmentary information on the quality of irrigation indicates that the acreage sown to wheat and rice HYV's may be approaching an upper limit in many areas because of the requirements of these varieties for a high degree of water control. Further gains will require more aggressive and coordinated policies for agricultural development. A major change in development strategy may be required if scarcities and hardships such as those currently being experienced are to be avoided in the future, and some hard political decisions on land reform and consolidation may have to be made. It is to be hoped that bold and imaginative agricultural policies will be followed, and that they will be accompanied by greater efforts to reduce population growth to manageable levels.     

我国食物供求的基本特征与态势

在大量数据统计分析的基础上，从时序，区域，数量，结构等不同层面系统考察了我国食物生产，消费，贸易，政策的基本特征与态势，结果表明：我国食物生产明显具有波动与阶段特征，弱质与低效特征，区域与大国特征，人均肉蛋奶菜消费增长迅速，已达到世界水平平均水平，但有明显存在城乡差别和区域差别，我国是一个粮食净进口国家，对国际市场的依存度上升趋势，调控中存在逆向调节和反应过度现象，政府对食物供求的调控政策具有应急     

Local or localized? Exploring the contributions of Franco-Mediterranean agrifood theory to alternative food research

Notions such as terroir and “Slow Food,” which originated in Mediterranean Europe, have emerged as buzzwords around the globe, becoming commonplace across Europe and economically important in the United States and Canada, Latin America, Africa, and Asia. Given the increased global prominence of terroir and regulatory frameworks like geographical indications, we argue that the associated conceptual tools have become more relevant to scholars working within the “alternative food networks” (AFN) framework in the United States and United Kingdom. Specifically, the Local Agrifood Systems (Systèmes Agroalimentaires Localisés, or SYAL) perspective, first articulated in 1996 by French scholars, seeks to understand the relationship between the development of local food systems and specific territories. We review the empirical and theoretical literature that comprises each of these perspectives, highlighting three areas in which SYAL scholarship may be relevant to AFN researchers. First, while AFN scholars tend to understand the “local” in terms of positionality, in a distributionist sense (vis-à-vis one’s relation to sites of food production or consumption or along commodity chains), SYAL studies frame local food systems as anchored within particular territories. Second, SYAL research places significant emphasis on collectivity, both in terms of collective institutions and shared forms of knowledge and identity. Third, although both perspectives are framed in opposition of the industrialization of the global food system, AFN scholars focus more on alternative distribution schemes (e.g., organic, fair trade, and direct marketing schemes), while SYAL researchers favor territorially anchored structures (e.g., geographical indications).     

The stability of DNA in human cerebellar neurons

Human tissues have carbon-isotope ratios (13C/12C) that reflect dietary ratios. This observation has been used to determine the extent of metabolic turnover of DNA in cells of the adult human cerebellum (90 percent of which are neuronal). If adult human neuronal DNA were metabolically stable, its 13C/12C would reflect that in the maternal diet during fetal development as nearly all neurons are formed during maturation of the fetal brain and do not undergo cell division thereafter. The 13C/12C ratios in the food chains and body tissues of Europeans differ from corresponding American ratios by about 50 parts per million on the average. Therefore, turnover was studied by comparing 13C/12C ratios in cerebellar DNA of American-born Americans, European-born Americans, and European-born Europeans. The 13C/12C ratios in cerebellar DNA from European-born Americans were closer to 13C/12C ratios in cerebellar DNA from European-born Europeans than from American-born Americans, indicating that there was little or no turnover of neuronal DNA.     

森林环境近地表自然风的动态特性

森林环境近地表自然风动态特性是森林环境风场、森林防火理论和室内空调设备送风模式等相关研究的基础.该文通过对北京林业大学鹫峰试验林场森林环境中的近地表自然风采样分析,研究了近地表自然风在二维方向的动态特性.研究结果表明主风向风速的速度均值和方差较大,但平均湍流强度却小于侧向风的平均湍流强度;自然风的风向变化非常显著,当风速均值较小时,风向角度的标准差较大,当风速均值较大时,风向角度的标准差较小;主风向与侧风向的二维风速分布呈正偏态分布,二维风速分布的偏度系数γ3>0,峰度系数γ4>3.其中,侧风向速度分布的偏度系数和峰度系数均明显大于主风向的对应值;近地表自然风在主风向与侧风向的二维风速信号均表现出很高的随机性.此外,主风向与侧风向的二维风速信号间的相关性很低.     

Data modeling to facilitate internal traceability at a grain elevator

Data management in food supply chains to facilitate product traceability has gained importance in recent years. This paper presents a relational database model to facilitate internal traceability at a grain elevator, which is one of the first nodes in a food supply chain. This approach for modeling traceability information in bulk food supply chains has not been studied in past. At an elevator, grain lots (inbound deliveries) are blended to meet buyer specifications, and individual lot identity is not maintained. As a result, an outbound shipment to a customer likely contains grain from many different sources. In a food safety related emergency, tracing the source of a problem or tracking other affected shipments would be nearly impossible. An efficient internal data management system could mitigate these problems by recording all grain lot transformations/activities, including movement, aggregation, segregation, and destruction as well as supplier and customer information. In this paper, a relational database management system is proposed that stores all necessary information, including product and quality information, related to the grain lots in order to enable product traceability. The system can be queried to retrieve information related to incoming, internal and outgoing lots and to retrieve information that connects the individual incoming grain lots to an outgoing shipment. Furthermore, this system can be used both to trace back to the source of a given lot and to track information about previously shipped lots forward. In addition to traceability application, the information stored in this database provides a comprehensive dataset for many applications including mass flow optimization, resource optimization and improved operational efficiency of the grain elevator.     

Influence of productivity on the stability of real and model ecosystems

The lengths of food chains within ecosystems have been thought to be limited either by the productivity of the ecosystem or by the resilience of that ecosystem after perturbation. Models based on ecological energetics that follow the form of Lotka-Volterra equations and equations that include material (detritus) recycling show that productivity and resilience are inextricably interrelated. The models were initialized with data from 5-to 10-year studies of actual soil food webs. Estimates indicate that most ecological production worldwide is from ecosystems that are themselves sufficiently productive to recover from minor perturbations.     

Nutritional status and diet composition affect the value of diatoms as copepod prey

The role of diatoms as key food for copepods at the base of pelagic food chains has been questioned recently on the grounds of toxicity. We show, using unialgal versus mixed algal diets of different nutritional status (i.e., nitrogen:carbon ratio) fed to Acartia tonsa, that diatoms per se are not toxic but that single-diatom diets are inadequate. Additionally, the nutritional state of the phytoplankton has a profound effect on copepod growth and growth efficiency. The ecological significance of laboratory demonstrations of diatom toxicity needs to be reconsidered.     

细胞壁微纤丝角和结晶区对木材物理力学性能影响研究进展

木材是由不同种类的细胞组成的天然材料,其实体物质是组成其结构的各类型细胞的细胞壁。细胞壁的超微构造主要包括微纤丝和结晶区,微纤丝角能表征纤维素微纤丝的取向,纤维素大分子链排列的有序程度及排列形态决定其结晶程度和微晶形态等结晶区特征。基于前人的研究,系统概述了细胞壁微纤丝和结晶区对木材物理力学性能影响的研究进展,重点围绕微纤丝角和结晶度2个方面,分别归纳了二者对木材密度、尺寸稳定性、木材声学等物理性质以及弹性模量、强度等力学性质的影响作用,同时阐述了微纤丝角与木材硬度和刚度以及结晶度与冲击韧性等的相互关系,并概述了细胞壁微晶形态对木材润湿性和纤维强度影响方面的研究进展,最后对今后的研究方向进行了展望。     

基于云计算的食品有毒有害物质检验检测大数据的风险分析算法及其应用

基于云计算,结合食品安全检验检测的完备性与最小性原理,将影响食品安全的多维因素降维成平均含量(AVE)、限量标准(STA)、超限率(OUT)、超限程度(OUD)和最大值(MAX)5个因素,并建立食品有毒有害物质检验检测大数据的风险分析算法。利用云计算技术实现对地理上分布广泛、动态、复杂性高的海量数据进行存储,并运用云计算的MapReduce计算框架进行智能的并行数据处理及计算,最后得到风险分析结果。通过对在基于Web端的实验室管理系统采集的1 000 000条检验检测数据结果进行风险分析,得出食品安全指数IFS远小于1,表明消费者人群的食品安全状态良好。