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1.
This paper reviews the economic framework for the delivery of livestock services to the poor. It is argued that the demand for livestock products is likely to increase rapidly and the ability of the poor to participate in the opportunities presented by this growth is linked critically to the availability of good service support, both on the input and output side. Governments therefore have a responsibility to supply the necessary public goods (including the institutions and legal frameworks), and the market infrastructure for facilitating the emergence of efficient markets for livestock services. The paper further argues that the dynamics of public policy in developing countries are much more complex than the simple application of economic logic. It is the larger political economy that often dictates policy choices. It is therefore important to integrate political economy and governance issues into the economic debate on livestock service delivery. The paper also reviews the context in which the markets for livestock services will need to function. Different countries are facing very different sets of issues, and the identification of possible interventions in livestock service markets would require careful field research and analysis. In this context, the paper suggests the elements of a research agenda for the next few years.  相似文献   
2.
龙超 《国际木业》2005,35(9):22-25
本文阐述了现代木结构建筑在中国的应用、研究现状、建筑实例,指出木结构在我国具有很大的潜在市场,并且有利于合理有效的利用我国的林木资源,生产出具有高附加值的产品,做到经济、社会、生态效益的三者相统一。  相似文献   
3.
依托"中国知网"的海量文献信息,采用文献计量学方法,利用中国引文数据库、中国学术期刊网络出版总库对《中兽医医药杂志》2001-2010年的发文量、下载量、被引情况、高被引论文栏目及学科分布、作者分布情况、基金论文比等相关指标进行统计分析,探索其中的变化趋势,并对其原因进行分析,以期为编辑部调整办刊及经营策略、更加科学地选题组稿、优化版面及栏目设计等提供参考依据。  相似文献   
4.
This study is based on the opinions of selected Iraqi extension workers, regarding the type and amount of training they need, given their experience in the field. The Borich Needs Assessment Model was used for measuring training needs. The data were collected through questionnaires given to 300 respondents (agricultural workers) from January 15, 2016 to March 20, 2016. The results show that crop-planting courses have the greatest benefit. The greatest training need is skill and knowledge of teaching methods, while a moderately needed skill is the use of computer and information and communication technologies (ICT); management skills are the least needed training.  相似文献   
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从生态系统服务视角出发优化生态安全格局,对于维护区域生态安全格局,确保经济社会稳定发展意义重大,但现有研究缺乏对多种生态系统服务之间权衡情景下生态系统状况的认知。该研究以黄河流域甘肃段为研究单元,在测度2019年食物供给、碳固定、产水量、土壤保持及生境质量5种典型生态系统服务的基础上,利用有序加权平均(Ordered Weighted Averaging,OWA)模型识别出生态系统服务权衡度最高的优先保护区作为生态源地,利用最小累积阻力模型和电路模型识别生态廊道和战略点区域,进行生态安全格局构建与优化。结果表明:黄河流域甘肃段生态源地斑块共计169个,总面积27 460.56 km2,约占研究区总面积的19.2%。5种生态系统服务之间在全流域尺度下呈现出协同关系,甘南高原、陇中、陇东黄土高原由于受地形气候和植被覆盖以及人类活动的影响,生态系统服务差异显著。利用电路模型提取得到441条生态廊道,总体呈网状分布,贯穿东西,识别出生态节点49个。提出构建\  相似文献   
7.
对数字图书馆服务环境重塑的必要性进行了阐述,并从四个方面对数字图书馆服务环境重塑进行了探讨与研究,希望能推动我国数字图书馆的发展。  相似文献   
8.
One problem with information delivery to a specific segment of the agricultural community is identifying the characteristics and needs of the end-user. Such a profile could be used for evaluation of the products or services provided. The Aquaculture Information Center of the National Agricultural Library was able to construct to such a profile based on historical data as well as current assessments from several United States aquaculture information groups. Analysis of this data provided specific and general direction for future products and services within the aquaculture information community. Findings also highlighted the important need for further tracking of such data, emphasis on continued networking among information groups, and creation of formal guidelines for aquaculture information access for the end-user.  相似文献   
9.
基于过程本体的奶牛养殖业信息协同服务系统的建立   总被引:2,自引:0,他引:2  
农业信息协同服务是农业信息化发展的重要方向之一,也是目前农业信息领域倍受关注的热点学术问题。该文将农业本体论思想引入农业生产经营过程,并以奶牛养殖业为例,探讨并划分了奶牛业生产经营过程阶段和对应的信息需求单元,构建了奶牛养殖过程本体和奶牛养殖业信息协同服务业务链模型,建立了基于业务链模型的奶牛养殖业信息协同服务系统,进而对系统的服务功能进行了初步实现。研究结果表明:建立在生物学特征基础上的农业过程本体在作为农业信息统一分类标准方面具有显著优势,基于过程本体的业务链模型有效地解决了农业信息资源优化调度和协同服务机制难题,实现了农业搜索服务和异构网站服务的协同。  相似文献   
10.
Abstract Catches of anadromous whitefish in the Gulf of Bothnia have declined since theearly 1990s. It is generally assumed that the cause is overfishing. The professional fishermeninterviewed in the present study were united in the opinion that it is necessary to set limits onthe fishing of whitefish, but had differing views about the means of achieving this. Thesedifferent arguments involved separate whitefish stocks, various types of gear and differentmotives for fishing. Most of the professional fishermen accepted a minimum mesh size for gillnets. Other means proposed included setting limits on non-professional fishing and sales ofcatches. There were conflicting attitudes about seasonal restrictions because their experienceswith fishing restrictions for salmon had been negative. On the whole, decision-making requiresmore regional information on whitefish stocks and fishing, but also on the social and economicflexibility of fishermen.  相似文献   
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