基于LASSO方法的四川农村居民食物消费支出影响因素探究

[目的]农村居民是乡村振兴的主体,其食物消费和膳食结构直接影响乡村振兴战略的顺利实施。四川省是我国西部农业大省,其农村居民的食物消费和膳食结构在中国西部地区具有一定的代表性。分析四川农村居民食物消费支出及其影响因素,对于改善农村居民食物消费和推进国家乡村振兴战略具有重要意义。[方法]根据经济发展水平进行分层抽样,选取四川省3市3县(区)156个农户,开展食物消费支出及营养认知问卷调研,采用LASSO方法对调研结果进行回归,筛选出影响农村居民食物消费支出的关键因素。[结果]在影响农村居民食物消费支出的主要因素中,家庭食物营养决策人的营养态度、家庭收入和决策人年龄与家庭食物消费支出都存在显著正相关;其中,决策人的营养态度相关系数最大,达到0.886,家庭收入和决策人年龄的相关系数分别为0.043和0.011;而在家就餐人数与食物消费之间存在显著负相关,相关系数为-0.020。[结论]影响四川农村居民食物消费支出的关键性影响因素主要有决策人的营养态度、家庭收入、在家就餐人数和决策人年龄;其中,决策人的营养态度是四川省农村居民食物消费的主要因素,且存在正相关,即决策人营养认知水平高对农村居民膳食结构优化具有重要的促进作用,这也表明营养知识宣传及消费引导的重要性。     

食物消费结构升级对农业碳排放的动态影响机制研究

[目的]探寻主要食物消费结构与农业碳排放之间的动态关联机制。[方法]基于1990—2015年面板数据,通过VAR模型进行研究。[结果]结果显示食物消费结构升级与农业碳排放确实有着一定的关联性,且存在一定的滞后性,但其影响程度和方向因食物种类而异。[结论](1)从影响方向看,农业碳排放对肉禽类、奶类等动物性食物消费和粮食、蔬菜、食用植物油等植物性食物消费变动的冲击响应方向基本相反,这主要是由动物性食物和植物性食物的替代性导致;农业碳排放对食物消费变化冲击的响应方向呈正负交替变化,且随着时间的推移而趋于平缓,主要是由于农产品供求的收敛型"蛛网"变动特点引起。(2)从响应时间看,农业碳排放变动对植物性食物消费冲击响应更为迅速,主要是由于动物类食物调整生产周期明显长于植物类食物产品;以植物性食物消费代替动物性食物消费的方式在短期内(3～4年以内)确实可以一定程度上降低碳排放,但是长期看来效果并不明显;所有食物消费变动对农业碳排放的冲击效应在8～9期以后均逐渐消失,说明食物消费结构的变动对农业碳排放的影响持久,农业碳减排任务不可能在短期内一蹴而就,而需要长期而持续的努力。(3)从影响程度看,方差分解结果表明,对农业碳排放变动的影响贡献最大的是其自身,说明农业碳排放基数庞大,减排工作任务艰巨,尽管肉禽类食物消费导致的碳排放量比重较大,但研究期间农业碳排放变动的并不是主要由这类食物消费的变化导致,而是由植物性食物消费变化导致。研究结果为在满足居民食物消费需求的前提下降低农业碳排放、发展低碳农业提供一定的依据。     

国外城市农业研究进展及展望

[目的]随着城市食物安全与环境问题的逐步显现,全球城市农业发展得到了更广的空间与政策支持,大量研究不断涌现。梳理国外城市农业研究,提出未来的研究方向与重点,以期为国内相关研究与管理工作的开展提供参考与支持。[方法]文章利用文献分析法、比较与归纳分析法,通过搜集国外城市农业研究的相关文献,从概念演变、研究主题、研究方法等方面进行了系统总结。[结果]国外已有研究主要包括城市农业与社会经济、城市农业与生态环境、城市农业发展评价与模式、城市农业发展环境4个主题,研究方法主要用到了社会调查、统计分析、地理信息技术、生命周期评估、试验分析等。[结论]国外城市农业研究研究视角不断延伸,内容更加综合,尺度不断细化,方法向多学科融合发展。我国应加强与国际研究接轨,满足未来可持续性城市与现代农业不断融合发展的需求。     

城乡居民膳食结构变迁对耕地资源的影响 ——基于1981—2019年中国城乡居民食物消费数据

研究目的：厘清城乡居民膳食需求与耕地资源之间的相互关系,以期为保障城乡居民健康营养的膳食需求及耕地资源的可持续利用提供科学参考。研究方法：膳食营养分析、耕地足迹方法。研究结果：（1）近39年来城乡居民植物性食物比例日趋减少、动物性食物比例上升,膳食能量、蛋白质、脂肪与胆固醇近几年均呈上升趋势,城乡膳食结构与营养差异在缩小;（2）受膳食结构、农业生产力及人口影响,城乡居民的人均膳食耕地足迹较于20世纪80年代均有所减少,但城乡居民的总膳食耕地足迹波动中有所上升,城镇居民的总膳食耕地足迹增加,农村居民的总膳食耕地足迹有所减少;（3）提高水果及奶类食物比例、减少畜肉食物是未来城乡居民膳食优化方向;（4）预计2030年中高能量理想膳食模型的耕地足迹将进一步增加,甚至超过中国现有耕地面积。研究结论：城乡居民膳食变迁将进一步加大耕地保护的压力,耕地保护对于保障国民健康营养膳食具有关键性的作用。     

外出务工对农户食物消费的影响研究*——基于中国西部6县的调查

[目的]为了厘清贫困地区外出务工与农户食物消费的关系,文章以西部贫困地区为例,研究外出务工对农户食物消费的影响。[方法]该文使用陕西省镇安县、洛南县,云南省武定县、会泽县和贵州省盘县、正安县2015年1 368户农户实地调研数据,将在家成员作为研究对象,采用倾向得分匹配法(PSM)调整样本的选择性偏差,降低内生性导致的估计偏误,分析外出务工的影响效果。[结果]采用最近邻匹配法、半径匹配法和核匹配法进行匹配后,发现外出务工使农户的人均食物消费总支出的对数最多显著提高0. 081%,最少显著提高0. 060%。[结论]外出务工主要通过收入变化、外来的信息或经验和人口变化3方面影响农户的食物消费,且西部贫困地区外出务工显著提高农户的食物消费水平。相关部门应关注贫困地区农户食物消费与营养状况,改善其食物消费结构,提高食物安全与营养水平。     

践行大食物观促进全民营养健康和可持续发展的战略选择

本文总结我国食物供需面临的挑战，剖析大食物观的科学内涵，从食物消费、生产和贸易角度研究大食物观发展路径，提出保障全民营养健康和可持续发展的战略思考。本文建议引导居民采取可持续健康膳食模式，同时制定相关政策降低营养食物价格和增加收入等保障低收入人群的健康膳食；以居民多样化食物需求和大资源观为导向，构建多元化食物供给体系，通过优化食物供给结构、挖掘多种资源、发展设施农业、研发未来食物、转型绿色低碳生产方式和完善全球食物供应链等路径，增强食物供给的可持续性。最后提出前置食物消费政策、扩大农业政策支持范围、优化支持方向、强化科技支撑、创新大协同管理机制和推进高水平开放等践行大食物观的战略选择。     

中国农业生态效率研究热点和趋势分析

目的 农业生态效率综合考虑经济效益和环境效益，是农业绿色发展的表征指标之一。通过梳理中国农业生态效率的研究热点与趋势，为中国农业生态效率和农业可持续发展的研究提供参考。方法 文章以知网数据库为基础，搜集整理1981—2022年中国农业生态效率领域的相关文献共433篇，从发文量、作者、机构基金和关键词方面进行研究。通过CiteSpace对作者共线、关键词共线、关键词聚类等进行分析，绘制可视化图谱。结果 （1）2011年后此研究领域的发文量开始增加，研究热点由关注农业环境理念向计量方法和影响因素转变，基础理论、评价测度和效率应用共同构成该领域的研究主题。（2）目前还存在学者间合作较少，研究相对独立；研究对象多为全国或省级层面，对县乡级研究有待深入；评价方法上较少使用复合模型；研究主题有待创新等问题。结论 在资源与环境双重压力下，农业生态效率的研究已成为现代农业绿色化发展的重要组成部分。     

基于CiteSpace的国内外农业面源污染研究进展与前沿分析

[目的]分析农业面源污染相关的国内外文献,探讨农业面源污染领域的发展历程、国内外研究热点和前沿,为今后研究提供参考。[方法]文章运用文献共被引、关键词共现和关键词突现的文献计量分析法,以Web of Science(WOS)核心数据库以及中国知网（CNKI）的相关文献为研究对象,对2000—2021年农业面源污染领域国内外研究历程及发展趋势进行分析。[结果]（1）农业面源污染问题受到国内外学者的广泛关注,中国发文量最多,占全球的46.18%;(2)对农业面源污染进行聚类分析表明目前国际上农业面源污染领域的知识群组主要集中在水土流失、氮和磷、农业面源污染模型、最佳管理措施、冗余分析等,而国内对农业面源污染的研究主要侧重于农业面源污染负荷、化肥、人工湿地、防治对策等方面。（3）在聚类分析的基础上进行关键词共现分析发现生物技术控制农田径流中氮磷污染、利用Geographic Information System(GIS)等技术建立多种模型并对模型进行集成与优化、确定经济技术上可行的最佳管理措施、识别源区域的风险水平和空间分布是该领域的研究前沿。[结论]利用农业面源污染模型、应用环境友好型技术...     

大食物观与国民营养健康

食物与营养是人类赖以生存的基础。党的二十大报告明确要求树立大食物观，构建多元化的食物供给体系。在这样的背景下，厘清大食物观与国民营养健康的双向互动关系，对于促进社会经济发展具有重要意义。本文首先介绍了大食物观的理论逻辑，并从大资源观、大消费观、大安全观、大农业观、大科技观、大协作观、大市场观七个方面阐释了其科学内涵。其次，本文分析了我国居民食物消费及营养健康的发展现状，并在此基础上研究大食物观对营养来源、营养结构、营养认知、健康保障、健康水平等方面的深远影响。再次，本文从食物系统发展、食物多样性、食物营养性、食物健康性、“食物—生态—农业”耦合性等方面分析了国民食物消费与营养健康的变化如何影响着大食物观的塑造。最后，本文提出以大食物观促进国民营养健康发展的政策启示。     

不同城镇化增长方案下畜产品消费趋势比较分析

[目的]畜产品消费占食物消费比重逐渐上升,中国快速城镇化进程与食物消费结构升级已经形成了历史性的交汇,但测度两者联系的研究不够充裕。文章探究两者之间是否存在内在联系,有助于弥补城镇化和食物消费关联性的文献缺口,也可以在城镇化发展过程中给相关部门提供一定参考。[方法]在统计描述中国畜产品消费历史特征的基础上,通过中国农业产业模型(CASM)对比分析不同城镇化背景下畜产品消费趋势,详细分析城镇化给畜产品消费带来的增长效应和结构效应。[结果]城镇化率越高,畜产品消费量就越多。从消费结构上看,未来脂肪和能量含量较高的猪肉消费比重下降较为明显,而富含蛋白质的牛羊肉、蛋类消费比重稍有增长,蛋白质和微量元素兼重的奶类消费比重上升较为明显。脂肪含量相对较少且环保压力较小的禽类消费增长速度是肉类中最快的,且其增速在未来或将逐渐超过奶类。从城乡角度看,农村居民畜产品增长速度快于城镇,但城镇总体畜产品消费量多于农村。[结论]最后建议优化畜牧业产业布局、标准化流通体系,加快推进农业结构调整,实现粮经饲统筹、农牧渔结合发展;健全畜产品消费可追溯体系,在做好畜产品检验检疫的基础上,准确把握畜产品消费趋势,引导居民合理消费。     

The Effect of the Structural Adjustment Program on the Output,Prices and Exports of Major Agricultural Export Crops in Nigeria

The primary objective of this paper is to examine changes in the level of output, prices and exports of major export crops resulting from the Structural Adjustment Program (SAP) in Nigeria. THere two main sources of data: the Central Bank of Nigeria (CBN) through its annual reports, Economic and Financial Review, and the Nigerian Federal Office of Statistics (FOS) through its Trade Summaries. Although the SAP led to appreciable increases in output and producer prices, its effects on exports were insignificant. The implications of these for the implementation of the program are explored.     

Revealing different understandings of soil held by scientists and farmers in the context of soil protection and management

This paper aims to analyse and draw together results from similar studies in England, Switzerland and France which investigated farmers’ understanding of soil and compared it with that of scientists, researchers and advisors (collectively called scientists in this analysis). A range of methods were used across the three studies and different theoretical approaches, looking at forms of knowledge, local practice of knowledge production and conceptions of reality, were employed to explain the results. Despite the different contexts, methodologies and theoretical approaches in the three studies, the results reveal similar patterns of difference in farmer and scientist understanding of soil. In the English study, farmers demonstrate a ‘know-how’ form or intuitive working knowledge of soil while advisors rely on scientifically established forms of ‘know-why’ and seek to understand and explain soil processes. Similarly in the Swiss study farmers’ and scientists’ differing perceptions are directed and shaped by their respective aims, methods and context of work. In the French study, farmers and researchers are shown to have different conceptions of soil, they attribute different meaning to the same activities, and use different words and language to describe the same features. In all three studies understanding is shown to be cultural and contextual, as such an integrative theoretical framework is proposed.     

森林生物多样性评价模型的改进

针对2002年的评价模型中的不足,提出了新的改进后的森林生物多样性变化的评价模型,并在我国第六次森林资源清查(1999～2003)资料的基础上,对1973～2003年我国森林生物多样性的变化进行了补充评价。评价结果表明:我国森林生物多样性的压力越来越大,压力指数由1973年的100,上升到2003年的199.10,上升了1.99倍;森林物种多样性总体的下降趋势已有一定幅度的改变,森林物种多样性指数增加了31.12%。森林生态系统多样性和森林生物多样性先逐渐上升,尔后又下降,第六次森林资源清查时又有所恢复,并分别上升了4.67个百分点和17.90个百分点。     

Trust-A monolithic panacea in land use planning?

Although trust research has been extensive and substantial, the constitution and actual merits of trust in land use planning remain nebulous. What do participants of a local land use planning process actually mean when they say they trust the planning committee? How important is participants’ trust in the planning committee in shaping their perceptions of the planning process and their cooperation in it? To explore the everyday meaning of trust in the specific context of local land use planning, semi-structured interviews with the participants of a local planning project in Switzerland were conducted (n = 9). Based on these results, the constitution and the relevance of trust in the responsible planning committee among a wider circle of participants were assessed (n = 66). The results show that participants trust the planning committee if they perceive its members as competent, honest, open, fair, reliable, reciprocating, respectful and committed. Interestingly, a considerable part of trust in the planning committee hinges explicitly on whether the committee incorporates the personal interests of the participant. Trust is indeed vital to participants’ belief that a meaningful discussion and cooperation with the members of the planning committee is possible. However, trust is neither a guarantee for people's approval of planning decisions nor for their cooperation. One implication of the findings is that in order to evaluate trust-building practice comprehensively, it is necessary to first understand the specific everyday meaning of trust for ‘real people’ in real planning processes.     

转变地质工作发展与服务方式的实践和建议

天津市地矿局注重加快转变经济发展方式,发挥地质工作优势,推进低碳清洁能源的开发利用创新和技术进步,紧紧依托地质工作的人才、技术和行业优势,加大清洁环保资源的勘查、研究、开发、利用。针对天津市水资源缺乏的情况,积极加强后备和应紧水源勘查。按照“两种资源,两个市场”的思路,通过实施中外合作勘查项目,以境外勘查工作为载体和平台,实施引进来和走出去战略,为天津市经济社会发展提供地质技术支撑。     

Agricultural Land in Vietnam: Markets Tempered by Family, Community and Socialist Practices

Since the late 1980s, markets involving agricultural land have emerged in the Socialist Republic of Vietnam. One major reason is that collective farms, previously a central feature of the country's political economy, ended. And a major reason for that was villagers' everyday politics gnawed the underpinnings of the collectives until they collapsed. Rural households, for the most part, wanted to farm separately. Today they do. Land is not privatized, however. Farming households have land use rights, not ownership. This tempers markets, as do other conditions arising from contending schools of thought in Vietnam about how land should be used, distributed and regulated.     

Conservation agriculture (CA) in Tanzania: the case of the Mwangaza B CA farmer field school (FFS), Rhotia Village,Karatu District,Arusha

This project was initiated to promote conservation agriculture (CA) in Tanzania so as to improve the food security and rural livelihood of small- and medium-scale farmers through the scaling-up of CA as a sustainable land management (SLM) tool as well as increasing the numbers of SLM-CA farmer field schools (FFS) in communities. The project had two phases from 2004 to 2010. It was funded by a Government of Germany trust fund and implemented by the Food and Agriculture Organization of the United Nations (FAO) and the Ministry of Agriculture in Tanzania. The project pilot districts include Arumeru (Arusha and Meru Councils), Karatu, Babati, Hanang and Moshi districts. CA has been shown to offer positive elements that could contribute to fighting hunger and poverty.     

Towards an Integration of R & D and Marketing in Production Development

Abstract

In this paper, two approaches which are characteristic for Research & Development and Marketing departments are compared. First, R&D versus Marketing orientations are explained, then the major differences between them are presented. The integration of both approaches may improve competitive advantage of the food industry. Factors stimulating such integration are presented on the basis of data from real business circumstances. Innovation is regarded as a major source of competitive advantage of company. Therefore, integration in sensory methodology, that is commonly but differently used by R & D and Marketing departments, may contribute to the improvement of innovation practices and successful business performance. Finally, the role of consumer tests, oriented for marketing and product development, is illustrated.     

Successful Practices in California Wine Exporting

Abstract

California is one of the world's largest wine producers, yet it has exported only a small portion of its products. Many US wineries want to pursue opportunities in foreign markets but only a few are actually doing this successfully. Therefore, this study attempts to identify the successful practices of 12 California wineries that have achieved their financial targets and other export goals. A qualitative research design of in-depth interviews was employed. Results indicate that there are 5 major success factors, with the two most important being the foreign partner relationship and top management vision and commitment to exporting.     

Time Allocation Decisions Associated with Job Market Preparation: Undergraduate Perceptions versus Market Realities

A survey of agribusiness firms identifies characteristics associated with above average starting salary offers in the allied fields of agribusiness, agricultural economics, business, and economics. A complementary survey is made of students at Texas A&M University and University of Georgia. Results show that firms value work experience and leadership experience more than students do, whereas students value raising grade point average and interview preparation more than do firms. Students seeking a firm's maximum starting salary offer will need to enhance academic performance with substantial work experience and leadership experience.