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11.
集成化农产品供应链管理是农产品供应链管理的核心内容,有效的农产品供应链可以解决农产品供应链的链接松弛问题,有助于我国"三农问题"的解决。建立农产品供应链结构模型是集成供应链的首要步骤,分析完全竞争下大宗农产品的特点和农产品供应链过程及关系,构建有效供应链的分析原则,对更有效的农产品供应链建立有借鉴意义。  相似文献   
12.
论实现世界旅游强国的人才建设   总被引:30,自引:0,他引:30  
陈志学 《旅游学刊》2001,16(3):34-38
目前,我国旅游人才建设仍存在总量不足、分布不合理、结构不理想、急需人才缺乏、人才外流严重等问题,为此,需要在确立积极的人才资源开发目标和工作思路,实施人才队伍建设工程,创新用人机制,优化人才环境等方面作出积极的探索。  相似文献   
13.
Organic agriculture, which produces commodities that can be qualitatively differentiated from conventional food products, has grown into an important market in many countries. The dynamics of commodity prices in both sectors are partly interdependent, but are also shaped by independent determinants and have rarely been studied. We analyze organic food markets and their interdependencies with conventional markets in the context of wheat markets in Germany, which have been subject to a number of fundamental changes during the last two decades. Based on institutional market characteristics, we suggest a flexible Markov‐switching asymmetric time series model. We find a pronounced temporal sequence of market phases that differ in their asymmetric dynamics and the extent to which the organic price is influenced by the conventional price. Organic wheat prices tend to be increasingly connected to prices of conventional wheat.  相似文献   
14.
[目的]以高分时序遥感影像为基础数据源,结合土地承包经营权地块数据,对冬小麦遥感估产方法及其精度进行研究和分析。[方法]文章以河南省兰考县为研究区,采用2019年4―5月份的GF-1C和GF-6 2 m PMS遥感影像提取了研究区冬小麦种植空间分布,并在地块单元控制下对冬小麦种植面积进行了修正和精度验证。其最优提取结果的修正阈值为0.93,地块单元内冬小麦总体分类精度为95.66%,Kappa系数为0.89。利用3月7日至5月20日6期GF-1 WFV遥感影像序列NDVI和RVI与冬小麦种植地块单元数据进行空间统计,得出各冬小麦种植地块单元内NDVI和RVI均值,通过分析冬小麦测产地块单元内均值植被指数与产量间的敏感性,提出一种组合均值植被指数的冬小麦遥感估产模型构建方法,通过交叉验证法对不同的估产线性回归模型进行精度评价。[结果]由4个均值植被指数组合变量的多元线性回归模型为最佳,决定系数为0.922 0,预测误差为40.96 g/m~2,预测精度为93.13%。通过该模型得出兰考县冬小麦平均产量为6 047.25 kg/hm~2,较2017年河南省统计年鉴研究区冬小麦平均单产6 001 kg/hm~2有所提高,土地承包经营权地块内和地块外冬小麦总产量分别为2.76亿kg和4 650万kg。[结论]该方法实现了冬小麦估产结果以像元为单位向以地块单元为单位的转变,解决了模型构建时光谱信息与实测产量间对应问题,为利用国产高分卫星进行县域地块尺度遥感单产精准化估算提供了方法支撑。  相似文献   
15.
Companies commonly issue sustainability or corporate social responsibility (CSR) reports. This study seeks to understand worldviews of corporate sustainability, or the corporate message conveyed regarding what sustainability or CSR is and how to enact it. Content analysis of corporate sustainability reports is used to position each company report within stages of corporate sustainability. Results reveal that there are multiple coexisting worldviews of corporate sustainability, but the most dominant worldview is focused on the business case for sustainability, a position anchored in the weak sustainability paradigm. We contend that the business case and weak sustainability advanced in corporate sustainability reports and by the Global Reporting Initiative are poor representations of sustainability. Ecological embeddedness, or a locally responsive strategy that is sensitive to local ecosystems, may hold the key to improved ecological sensemaking, which in turn could lead to more mature levels of corporate sustainability worldviews that support strong sustainability and are rooted in environmental science. This must be supported by government regulation. Copyright © 2017 John Wiley & Sons, Ltd and ERP Environment  相似文献   
16.
用循环经济理念发展小麦产业——以安徽省淮北市为例   总被引:1,自引:0,他引:1  
农业循环经济是一种新兴的经济发展模式,发展循环农业是实施实现农业可持续发展战略的重要途径。该文以安徽省淮北市为例,从农业循环经济理念的角度分析小麦产业存在的问题,并提出投入减量化,产出最优化,主副产品再利用、再循环,构筑小麦产业经济利益共同体以及优惠政策支持等小麦产业发展对策。  相似文献   
17.
Participatory plant breeding began in developing countries and now some European farmers and scientists are proposing its suitability in contributing to sustainable agriculture. This paper uses both genetics and sociology to determine the conditions required. A review of the sustainability of projects implemented in developing countries initiated discussion of an organic durum wheat participatory breeding programme, which is currently being implemented in the south of France. The analysis highlighted the need for the critical participation of experts from different horizons in a socio-technical network. Multi-level interactions and cross-linked learning processes about breeding methods and sociological concepts are needed for effective communication between different stakeholders and scientific disciplines. This approach enables implementation of a range of different action systems in which the production of relevant knowledge and rules addresses the issue of the sustainable development of diverse agro-food systems, rather than the generalization of one model.  相似文献   
18.
中国股票市场有效性实证分析   总被引:1,自引:0,他引:1  
马岩祥 《新疆财经》2009,(5):47-50,77
股票市场的有效性直接影响资金配置的效率,中国股市的有效性问题一直是业界讨论的焦点,其有效性的检验主要集中在市场是否具有弱式有效方面。本文依据Fama对股票市场的定义及三个层次市场对应的有效市场检验方法,对国内股市的有效性进行检验。首先使用沪、深两市日收益率数据,对各自日收益率之间的相关性进行检验,发现日收益率之间不存在自相关和偏自相关,由此认为中国股票市场弱式有效。然后采用事件研究法,以年报公布作为事件,以年报公布日前、后共30日,120支股票收益率数据为样本,对我国股票市场半强式有效性进行检验,结果发现年报公布日前、后超额收益存在明显变化,以此认为中国股市目前不符合半强有效市场的定义。最后对市场中存在的问题进行了分析,并给出了政策建议。  相似文献   
19.
Using wheat market support data from 55 countries for 1961–2011 from the World Bank Agricultural Distortion database, we develop a fixed effect model that shows a more complicated, nonlinear relationship between income and wheat support and its components than previously realised. We find that income generally has a greater effect on border market price support than on domestic price support. Moreover, the difference between these types of support is greater for net importers than for net exporters and has increased with the URAA or WTO accession. Holding other variables constant, the wheat support level of China, driven mainly by border market price support, is projected to rise with future income growth. Meanwhile, Japan is projected to maintain its high level of support, while the US and EU are projected to maintain their lower levels of support. These results are relevant in the context of multilateral trade negotiations, arguing against a narrow focus on past or current policy profiles and for long‐run analyses that might mistakenly rest on the inconsistent assumptions of constant agricultural policies against the backdrop of rising incomes.  相似文献   
20.
With continually increasing demand for food accompanied by the constraints of climate change and the availability and quality of soil and water, the world’s farmers are challenged to produce more food per hectare with less water, and with fewer agrochemical inputs if possible. The ideas and methods of the system of rice intensification which is improving irrigated rice production are now being extended/adapted to many other crops: wheat, maize, finger millet, sugarcane, tef, mustard, legumes, vegetables, and even spices. Promoting better root growth and enhancing the soil’s fertility with organic materials are being found effective means for raising the yields of many crop plants with less water, less fertilizer, reduced seeds, fewer agrochemicals, and greater climate resilience. In this article, we review what is becoming known about various farmer-centred innovations for agroecological crop management that can contribute to agricultural sustainability. These changes represent the emerging system of crop intensification, which is being increasingly applied in Asian, African, and Latin American countries. More research will be needed to verify the efficacy and impact of these innovations and to clarify their conditions and limits. But as no negative effects for human or environmental health have been identified, making these agronomic options more widely known should prompt more investigation and, to the extent justified by results, utilization of these methodologies.  相似文献   
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