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1.
[目的]对国内外的秸秆肥料化利用研究现状、研究热点和发展趋势进行整体分析,总结秸秆肥料化领域中存在的主要问题,为今后我国秸秆肥料化利用提供参考和建议。[方法]文章基于Web of Science核心合集数据库和中国科学引文数据库,采用Gephi软件对文献进行可视化计量分析,主要对1999—2019年国内外有关秸秆肥料化利用领域的国内外研究力量、研究热点以及研究趋势进行分析。[结果](1)2006年以后外文文献呈快速增长趋势,而2016年以后中文文献进入基本稳定阶段。(2)外文文献发表数量最多的研究机构依次为中国科学院、美国农业部农业研究中心和加拿大农业与农业食品部;中文文献数量最多的研究机构依次是西北农林科技大学、南京农业大学和甘肃农业大学。(3)外文文献发表数量排名前三的期刊分别是Soil and Tillage Research、Soil Biology and Biochemistry、Agronomy Journal,其中Soil Biology and Biochemistry单篇平均被引频次最高(52.5次/篇);中文文献发表数量排名前三的期刊分别为《农业工程学报》《农业环...  相似文献   

2.
[目的]利用Cite Space可视化文献分析软件,对1985~2015年CNKI总库中文核心期刊和CSSCI中文社会科学引文数据库中土地整治研究的5 309篇文献进行可视化分析,得出当前土地整治研究热点、作者群以及主要研究机构的知识结构图谱。[方法]文章采用了文献计量可视化方法和对比分析法。[结果](1)自中国土地学会成立以来,中国土地整治研究主要围绕"土地整理"、"土地整治"、"国土资源"等展开;(2)国土资源部、西南大学、中国地质大学(北京)等是主要的研究机构;(3)《中国土地》是土地整治相关研究刊载论文数量最多的期刊,《中国土地科学》、《农业工程学报》以及《资源科学》是刊载土地整治研究论文重要的核心期刊。[结论]除了传统的土地整治视角下,建设用地减量化,城乡建设用地增减挂钩项目区设置,农村居民点用地整治潜力评价、布局和空间结构优化以及农户整治意愿影响因素、未利用土地开发适宜性评价、工矿区土地复垦等研究外,在新的国内形势影响下,资源经济效益评价以及绩效评价等也是重点的研究方向。  相似文献   

3.
区块链技术的快速发展对各行业发展产生了显著影响,为了探析区块链技术对会计领域研究的具体影响、 预测区块链技术在会计领域研究的发展趋势.本文选取中国知网数据库会计领域内区块链为主题的中文期刊文献,利用文献计量分析方法、 大数据可视化方式对2021年2月8日之前发表的331篇期刊论文进行发文量、 研究热点、 研究机构及研究...  相似文献   

4.
近年来,农业绿色生产成为国内学者研究的热点话题。基于2000—2021年中国知网(CNKI)数据库收录的294篇北大中文核心和CSSCI文献,运用Citespace进行可视化分析。分析结果显示,有关农业绿色生产的文献总数稳步提升;研究内容主要集中在农业绿色生产技术采纳、低碳经济背景下的低碳农业、政府引领背景下农业绿色生产转型;研究热点演化过程分为三个阶段,先从消费端出发研究绿色食品生产,到对低碳农业及推行制约因素的探索,再到乡村振兴背景下农业农村绿色发展。今后研究方向应聚焦于农业生产绿色转型的顶层政策设计、加强农业绿色生产行为、绿色服务的融合发展等。  相似文献   

5.
本文采用文献计量和知识图谱可视化的方法,对SCI和SCIE中有关农业地理信息的论文进行定量统计和定性分析。自1991-2015年共有15127篇有关农业地理信息的文章发表。以"Agro-geoinformatics"为检索关键词,从文章发表数量、地理分布、国际之间合作以及关键词等方面进行统计分析,解释了农业地理信息在过去25年的发展特点和发展趋势。研究表明:(1)农业地理信息的相关研究一直呈增长的趋势,在近年来,增长更为显著。(2)研究贡献最多的机构是中国科学院,贡献最多的国家是美国。(3)关键词分析中以"遥感"、"GIS"、"精准农业"、"土壤湿度"等关键词近年来的迅速增长代表了农业地理信息的研究热点。  相似文献   

6.
中国耕地变化文献分析:数量特征、研究区域与文献来源   总被引:1,自引:0,他引:1  
[目的]分析2002~2016年中国耕地变化研究文献的数量特征、研究区域与文献来源,明晰中国耕地变化研究在文献数量、研究区域与文献来源3个方面呈现明显特征的原因。[方法]文章采用了文献分析法、分类统计法和比较分析法。[结果](1)耕地变化的研究内容、领域和方法逐渐趋于多元化,对耕地变化的驱动机制进行分析逐渐成为研究热点。(2)耕地变化的研究热度在全国第二次土地调查前后达到最高峰,研究热点区域多集中在生态脆弱区、耕地面积变化速率较快或中东部经济发达区,研究尺度多为省内行政区。(3)耕地变化文献刊载期刊种类繁多,多数与农业科技相关,以高等院校及研究院为研究主体的耕地变化相关核心研究体系已初步形成。[结论]一是耕地变化的研究领域与内容日益丰富,较完善的研究体系初步建成;二是耕地变化相关研究多以数量为主,质量考虑较少,研究尺度和研究区域具有局限性仍亟待完善。  相似文献   

7.
建立保护地是生物多样性保护的重要途径,保护地管理也成为全球生态和环境研究领域的焦点。文章基于"Web of Science核心合集"数据库,检索得到1990-2020年间与保护地管理相关论文1083篇并进行可视化分析,主要内容有文献基本特征、研究能力、知识基础与研究热点等。结果表明:(1)保护地管理领域的论文数量和被引频次呈上升趋势,保护地管理具有重要的研究价值。环境科学与生态学是该领域研究的主流学科,《海洋与海岸管理》是发文量最高的期刊,《生物保护》是最具影响力的期刊;(2)不同国家或机构在保护地管理领域的研究实力有所差异,美国发表的论文数量最多且具有较高学术水平,其研究强度和学术影响力也有较大优势,澳大利亚昆士兰大学是该领域的重点研究机构;最知名的作者Hockings也来自澳大利亚;(3)在保护地管理领域,具有高被引频次和高中介中心性的10篇论文发挥了关键的演变和推动作用,对后续研究产生了深刻影响;(4)关键词聚类分析表明,保护地管理领域热点问题主要围绕共同管理、生物多样性保护、种群、森林、海洋保护等方面展开;(5)关键词爆发分析表明,保护地管理领域的前沿问题主要有生态系统服务功能、保护地治理机制及效果、共同管理影响评估、保护绩效指标构建与评价和保护地管理挑战探究等。最后,探讨了全球保护地管理研究对于中国的参考与借鉴。  相似文献   

8.
[目的]通过国际食物消费可持续性研究领域动态分析,为食物和可持续发展领域研究方向与趋势提供知识基础与借鉴。[方法]文章基于文献计量研究方法,通过趋势分析、合作网络、共被引和关键词共现等分析,对1986—2019年国际食物消费可持续性相关研究进行了总结。[结果](1)近30多年来食物消费可持续性研究不断发展,尤其是近10年来,呈现快速发展趋势;研究主要集中在环境、食物、营养、农业和生态领域。(2)食物消费可持续性研究最多产的作者和机构位于美国和欧洲国家,中国是亚洲的一个重要节点,但研究总体仍有待进一步加强;联合国粮农组织(Food and Agriculture Organization of the United Nations,FAO)为食物消费领域与其他众多领域的研究构建了重要的桥梁;发表在Science和Nature期刊的相关研究成果是食物消费可持续性研究领域的重要基础。(3)食物消费可持续性研究的主题主要包括食物与农业系统可持续性、食物安全与营养健康质量和食物消费资源环境效应及可持续性评估三个方面。[结论]发展中国家和欠发达地区食物消费可持续性研究有待加强,同时食物消费可持续性...  相似文献   

9.
采用主题词的检索方法,通过对CNKI和Elsevier、Springer Link、ACS等外文数据库的检索,得中文文献418篇(1911~2016年)、外文文献11 985篇(1911~2016年)、专利135项(1980~2016年)。经文献计量分析,结果表明:我国稻壳的研究正处线性增长阶段,稻壳的加工与利用除了传统的用于制备白炭黑、水泥添加剂和稻壳炭等,已拓展至冶金、化学试剂、电子化工、医药、化妆品、粮食储藏、食品添加剂、农业和光伏等众多领域,且日益扩大和完善;稻壳资源利用的明天会更好,稻壳能更好地造福人类。  相似文献   

10.
基于CiteSpace的国内乡村振兴研究热点及趋势可视化分析   总被引:1,自引:0,他引:1  
[目的]文章通过绘制乡村振兴领域的科学知识图谱,考察了国内有关乡村振兴研究的发展脉络,旨在厘清国内乡村振兴研究现状,挖掘乡村振兴研究热点,探测乡村振兴热点变迁,并找出存在的不足与问题,以期为进一步的研究提供导向。[方法]利用文献可视化分析工具CiteSpace,对2017—2019年中国知网数据库收录的以"乡村振兴"为主题的文献进行了可视化分析。[结果]国内乡村振兴领域研究成果持续增长;文献学科结构倾向明显,以经济、政治、管理类为主;高产作者以刘彦随、龙花楼、姜长云、郑风田等15位为代表,合作关系呈现出"大分散,小集中"的特点;中国社会科学院农村发展研究所、中国科学院地理科学与资源研究所和中国人民大学农业与农村发展学院是发文量最多的3个机构;关键词的聚类确定了乡村振兴研究的4个热点主题,分别是"乡村振兴战略""乡村生活""农业农村现代化""产业兴旺";时区视图显示,乡村生活、乡村共同体、乡村社会建设和聚集人口等是乡村振兴领域研究的新热点。[结论]未来应提升乡村振兴研究所涉及学科的广度与多元化,加强各学者、机构之间的交流与合作,注重学术资源分布的地区差异问题;通过对研究热点及其演化脉络分析得出,未来应关注工业反哺农业实现乡村振兴的理论研究,关注脱贫攻坚与乡村振兴的衔接以及乡村振兴的制度建设问题,注意综合定量与定性研究方法的使用,充实升华新视角提出新观点,同时注意战略实施过程中各类矛盾的识别、分析和协调。  相似文献   

11.
The theory of demand and supply implies a positive relationship, or “price transmission” between the prices of products at different stages of manufacturing. This relationship was investigated with quarterly prices of softwood stumpage in the US South, and national prices of forest products, from 1977 to 2002. All prices, net of inflation, were found to be nonstationary and there was no evidence of co-integration between prices. Vector autogressive models, augmented by Granger causality tests and multiplier analysis showed that there was a one-to-one permanent positive response of the southern sawtimber stumpage price to a permanent change in the national lumber price. There was also a one-third permanent positive response of the national paper price to a permanent change in the national pulp price. There was no relation between regional pulpwood prices and national pulp or paper prices. When price transmission was significant, the full adjustment took about 2 years.  相似文献   

12.
Owners, local residents, government, and conservation organisations can express divergent preferences in the development and management of local woodlands. The perceptions of these four groups were examined, in the context of three community woodlands in Eastern England, using an ecosystem function framework. In a pilot study, residents were able to allocate a relative importance to woodland ecosystem services which were then related to “regulation”, “habitat”, and “production” or “information” functions. However residents also placed importance on negative services or “dis-services” associated with the woodland ecosystem. Therefore a fifth category of “dis-services” was included in the main survey which included 84 local residents, three woodland owners, three government institutions, and six representatives from conservation groups. Each of the four groups placed greatest importance on services associated with habitat (16–39% of the total importance) and information (30–50%) functions suggesting, in this example, mutual interest in the use of woodlands as a habitat or recreational resource. By contrast a potential area of difference was the particularly high importance placed by one owner on dis-services such as fly tipping. In addition the woodland owners placed higher importance (10–20%), than local residents and conservation groups (7–9%), on the productive services of the wood. This suggests a need for communication when production-related operations affect recreation. The ecosystem function framework appears to be a useful approach for highlighting potential tensions and areas of mutual interest in the management of semi-natural ecosystems.  相似文献   

13.
China is one of the largest wine importing countries in the world and is poised for continued import growth in the future. Increased wine purchases throughout China have given rise to persistent fraud where fake wines are packaged and sold with counterfeit contents and labels. For exporting countries like France, counterfeit wines displace market share, damage foreign brand reputation, and cause distrust in consumers who are aware of counterfeiting problems throughout the country. We examine the impact of fraudulent wine events (as measured by negative media reports) on Chinese wine demand differentiated by supplying country. We employ the Rotterdam demand system and a switching regression procedure to estimate import demand and compare results across different media variable specifications. Results consistently show that negative reports disproportionately affect French wine regardless of how the media variable is specified. This is not surprising because most fraudulent events involve French wine counterfeits.  相似文献   

14.
In recent years earthquakes and their secondary hazards have claimed the largest number of lives of all large natural disasters. Some of the world’s most earthquake-prone zones are also areas of high population density. The impact is magnified by vulnerability factors including non-enforcement of building codes, knowledge gaps, urban poverty and poor governance capacity to manage and reduce earthquake risks. Poor security of land tenure and property rights increases the vulnerability of people and affects their ability to respond to natural disasters.Earthquake recovery and reconstruction provides very significant challenges for land agencies, with these challenges differing from one country to the next due to differences in the local context. Drawing on contrasting case studies in Haiti, Nepal and New Zealand this paper identifies the common post-earthquake land administration functions and challenges that may apply to many contexts. These lessons provide land agencies and other key stakeholders with a summary of the challenges an earthquake poses for land administration at different post-disaster stages. We also discuss the policy and regulatory, institutional, operational and preparedness lessons for land administration. From these lessons we propose a framework for evaluating the earthquake-responsiveness of a land administration system. This framework can be used by a land agency in an earthquake prone region, or where an earthquake has recently occurred, to assess what challenges to land administration might occur in the event of an earthquake, and the preparedness of their land administration system.  相似文献   

15.
This paper analyses poverty and calorific undernourishment in the Indian state of Gujarat, where high and market‐led industrial growth has resulted in rapid economic improvement. The study is carried out through a combination of secondary and survey‐based data. We conclude that the neoliberal agenda of uncontrolled, outward‐looking growth has not resulted in significant reduction of poverty or malnourishment in rural areas. Furthermore, while land ownership is officially used as a proxy for wealth distribution, class position appears a better predictor of poverty status in the rural areas than landownership per se. At the policy level, there is a need to revive the agrarian economy and create new non‐agricultural assets, and the primary focus in the state must shift to the distribution of created assets rather than a single‐minded focus on growth.  相似文献   

16.
This paper tests the ‘systems of innovation’ hypothesis for a selection of crops in Ghana and Burkina Faso that have shown significant growth in production over an approximately 20-year period. The question is whether such growth can only occur if supported by a system of innovation. Using two indicators (a common understanding on objectives and priorities, and a high level of interactivity), we find little evidence for the existence of anything that might be considered a high functioning system of innovation.  相似文献   

17.
The values ascribed to industrial tree plantations are often controversial. Hence knowledge of their perceived impacts is important for improving their integration in rural landscapes. In 2016 we conducted household surveys with 606 respondents living in villages adjacent to acacia, teak and pine plantations across three islands in Indonesia (Java, Borneo, Sumatra). Results show that perceptions toward pine and teak plantations tend to differ from those toward acacia pulpwood plantations in several ways. Pine and teak plantations are perceived to have a higher number and variety of benefits and services, a higher number of positive impacts, a better environmental record, and to present more opportunities to local people for use of plantation land and products for improving rural livelihoods. In addition, we find that villagers around acacia pulpwood plantations tend to seek economic development and infrastructure to open up remote areas, yet their expectations were often only partially met. Recommendations from our analysis include: the role of the State in plantations must be clarified and potentially reinforced; the role of institutions as intermediaries is fundamental; and contributions by communities to design of management plans should be accommodated.  相似文献   

18.
Large‐scale tree plantations in high rainfall upstream areas can reduce fresh water inflows to river systems, thereby imposing external costs on downstream irrigation, stock and domestic water users and wetland interests. We take the novel approach of expressing all benefits and costs of establishing plantations in terms of $ per gigalitre (GL) of water removed annually from river flows, setting upstream demands on the same basis as downstream demands. For the Macquarie Valley, a New South Wales sub‐catchment of Australia’s Murray‐Darling Basin, we project changes in land and water use and changes in economic surpluses under two policy settings: without and with a policy requiring permanent water entitlements to be purchased from downstream parties, before plantation establishment. Without the policy, and given a high stumpage value for trees ($70/m3), upstream gains in economic surplus projected from expanding plantations are $639 million; balanced against $233 million in economic losses by downstream irrigators and stock and domestic water users for a net gain of $406 million, but 345 GL lower mean annual environmental flows. With the policy, smaller gains in upstream economic surplus from trees ($192 million), added to net downstream gains ($138 million) from sale of water, result in gains of $330 million with no reduction in environmental flows. Sustaining the 345 GL flow for a $76 million (406–330) reduction in gains to economic surplus may be seen to cost only $0.22 million/GL; but this is much lower than the market value of the first units of that water to agriculture and forestry.  相似文献   

19.
Fieldwork shows that many Sierra Leonean producers do not receive the official producer price for their coffee and cocoa, due to the concentration of buying stations, credit relations, the small quantities offered for sale, and the lack of marketing knowledge of the numerous and unorganized farmers. To the traders underpayment may seem economically justifiable to a certain extent, but to the farmers it means poverty and debt. A new village marketing centre project aims at remedying this situation and has already led to higher prices. Although no longer allowed to take their "just" share from the producers, traders are still willing to deal with the new centres.  相似文献   

20.
The cost of accessing healthcare can be a major determinant of disease prevalence, which in turn has short‐ and long‐term welfare implications on poor households. In response, governments in developing countries often resort to subsidizing the cost of drugs, which, while perhaps easier to administer, may not always be the most effective way of addressing healthcare cost. In this regard, we analyze the impact of different types of household level health expenses on disease incidence and agricultural production efficiency. We use data from the 2006 Uganda National Household Survey, which covered approximately 7,400 households. The results suggest that a 10% increase in consultation, medicine, and hospitalization expenses would reduce malaria incidence respectively by 35.6%, 20.5%, and 21.3 %, which translates into a 1.1%, 0.6%, and 0.6 % decrease in agricultural inefficiency, respectively. The results indicate that helping poor households meet expenses for consultation through subsidies or eliminating consultation fees has a larger impact on malaria incidence and agricultural productivity among poor rural households than subsidizing the cost of medical drugs, the most common avenue chosen by developing country governments in the fight against the disease.  相似文献   

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