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1.
全球气候增暖对甘肃农作物生长影响的研究进展   总被引:14,自引:2,他引:14  
系统总结了甘肃省科技攻关重大项目“甘肃干旱生态环境对全球气候变暖的响应研究”等3个课题的主要成果和研究进展。在揭示甘肃省现代气候变化基本特征是冬暖夏干的基础上,比较系统地综述了越冬作物(冬小麦、冬油菜)、喜凉作物(春小麦、马铃薯、胡麻)和喜温作物(玉米、棉花、酿酒葡萄)等8种主要农作物的生长发育、适生种植区高度和种植面积、产量和品质等对现代气候变化的响应特征。现代气候变化对甘肃农作物生长的影响非常突出,已对农作物安全生产与农业可持续发展构成了严重威胁。其研究结果为建立现代农业发展模式,旱作农业生产机制,农作物安全生产提供科学的指导意见。  相似文献   

2.
This article examines how law is implicated in the formation of place, and how place in turn can shape law. It is an empirical explication of Latour’s call for researchers to study the global through its local instantiations. Drawing upon recent theoretical work in both material culture studies and legal geography the article examines the interplay of law and material formations at one originating site, Sir Richard Arkwright’s Cromford Mills in Derbyshire in order to examine the creation and circulation of a new form of place in the late eighteenth century: the industrial scale cotton mill. It shows how a diverse range of legal elements ranging across patent law, the Calico Acts and ancient local Derbyshire lead mining laws all helped to shape that place-form, its proliferation across the United Kingdom, and ultimately further afield. In doing so the article conceptualises processes of localisation, translocalisation and thing-law by which the abstractions of both place-forms and law elements become activated through their pragmatic local emplacement. Whilst the case study concerns 200 year old place-making machinations, many of the spatio-legal articulations of Arkwright and his opponents have a surprisingly modern feel about them. The paper therefore advocates the benefits of a longitudinal, historical approach to the study of place-making, and in particular, calls for a greater attentiveness in legal geography to law’s role in the intentional formation of (work)places by their owners.  相似文献   

3.
Michael Flitner 《Geoforum》2003,34(2):175-185
The article deals with the role of genetics in the state-led agricultural modernization efforts that took place in different industrialized countries during the course of the 1920s and 1930s. A comparison between Germany, the Soviet Union and the United States shows substantial similarities in their attempts to increase the productivity of agriculture on different geographical scales. Following advances in scientific knowledge about the geography of cultivated plants, these countries sent out numerous expeditions to collect plant breeding material from all over the world. At the same time, states tightened their grip on farmers’ and breeders’ activities inside the country by establishing legal rules for the use of plant varieties and seed. But this was only one side of a larger “genetic modernization” project. In all three countries, concepts of agricultural modernization were substantially linked to social-darwinist thought which embraced programs of eugenics and “racial hygiene”. These links are outlined for each of the cases, highlighting the widely differing intermingling of scientific concepts and terminologies with political ideologies. It is then discussed what role geography and in particular geopolitical thinking of the time were to play in the development of “genetic modernization”, and more specifically, with regard to the nexus between agriculture and eugenics. While the discipline’s involvement in both fields remained comparably marginal in practical terms, clearly there were conceptual contributions toward the development of the broader field. Going back to Ratzel’s and Kjellén’s work, it is argued that geography had an important role in the establishment of a political field in which ideas of managing human reproduction were fused with concepts of economic development and environmental determinism.  相似文献   

4.
The ecological environment in arid areas is extremely fragile and especially sensitive to climate response. Continuous research on the climate and its impact mechanism in the arid zones is of great scientific significance for deeper understanding of the cause of climatic formation and better prediction of climate in arid regions. Some research progresses in recent decades both at home and abroad have been overviewed, including the distribution of arid areas, the causes of arid area climatic formation and arid area climate change. Studies have shown that AI index is an effective criterion for dividing arid areas. There are 8 major arid areas in the world; climatic formation in arid areas is the result of multiple factors; there are 6 kinds of influencing factors, such as Hadley Cell, land-air interaction and so on; the unlikely trend between dry and wet is obvious in arid areas, and some regions are facing more severe drought trends such as North Africa and China-Mongolia, while others show a trend of wetting such as the Midwest of the United States. At present, there are still some scientific problems to be solved urgently:The response of various arid regions to global warming is quite different, and climate prediction in these zones is both important and difficult; the uplift of the Qinghai-Tibet Plateau has a tremendous impact on the arid area of China-Mongolia, but the models of this field are not perfect enough; there are no accepted conclusions about the causes of climatic formation in different arid regions and the causes of their different wet and dry trends. At present, it is still impossible to quantitatively distinguish the relative contributions of various influencing factors in the climate evolution of drylands and their response processes.  相似文献   

5.
赵纪东  郑军卫  唐金荣 《地质通报》2017,36(9):1674-1681
拥有130多年历史的美国地质调查局经久不衰,关键在于其时常将满足不断变化的国家与社会需求作为生存与发展之本。对GeoRef数据库收录的自1970年以来的科研论文的定量分析发现,美国地质调查局的科学研究在1990年左右发生了重大转折:论文产出数量摆脱长期低迷状态,开始大幅增长;形成完整学科体系,学科综合度保持稳定;科研工作从以资源研究为主的供给型地质学转向以环境研究为主的需求型地质学;基于学科持续度指标识别出9个重点学科,它们在1990年之后进入相对稳定的发展态势,未来水文地质学和环境地质学或许仍是重点所在。基于关键词的研究热点分析,结合重点学科的发展演化,可以发现其研究重心发生明显转移。  相似文献   

6.
This paper questions geographers’ ability to think about power and violence through different epistemological registers, specifically by examining the discursive production of Palestine as place in geopolitical studies. Although the banner of geopolitics groups together a variety of approaches, these studies more or less cohere around a very particular type of imaginative geography of place - as violent and political. Recent arguments for cosmopolitan approaches to place - particularly when encountering non-Euro/American sites - are used to argue for more diverse approaches to places such as Palestine within Anglophone geographical scholarship. Using research on Palestinian family spaces and spacings, an alternative approach is outlined that exposes some geographies of dealing with and getting by the Israeli Occupation that are largely ignored by geopolitical approaches. These tropes prompt a return, in the conclusion, to the question of how geographers analytically apprehend power and violence, and the possibilities for doing this at the limits of, and beyond, the framework of geopolitical analysis.  相似文献   

7.
While plant diseases have been the subject of scientific research, little is known about the perceptions of key actors towards plant disease risk within specific food sectors. Drawing on concepts of risk and uncertainty, and using in-depth interviews, this paper examines the ways in which endemic plant disease risks in the UK wheat sector are perceived and managed by key ‘upstream’ and ‘downstream’ businesses, as well as by farmers and agronomists. A majority of interviewees feel that plant disease is a controllable risk and one that rests mainly at the point of production (i.e. with farmers) within the wheat sector. This assumed ‘control’ is based mainly around the availability of plant protection products (e.g. fungicides) which reduce the sense of risk attributable to outbreaks of plant disease. As a consequence, there can be a tendency to grow higher-yielding wheat varieties that are less disease-resistant. The potential banning of certain fungicides under EU legislation and climate change are perceived future threats that could increase uncertainty and change the balance between ‘control’ and ‘resistance’, the latter through the use of more disease-resistant wheat varieties. Further research is needed on the perceived impacts of plant diseases and on how different wheat sector actors will contribute to the future control of plant diseases and the development of more integrated systems of plant disease management.  相似文献   

8.
In the United States, geography is taught most frequently in the junior secondary schools, is somewhat more limited as a regular course in the senior secondary schools, and is a prominent discipline within many college and university programs of instruction. At the secondary school level, geography is usually integrated within the broader based social studies, while at the college and university level it has an important function both within general education as well as specialized training. At the pre-collegiate and collegiate levels geography has developed quite independently at times, and at other times there has been a close relationship that has benefitted both levels of education. At the end of the 1980s decade, considerable cooperation was underway in the United States between teachers of secondary school and tertiary level geography in order to upgrade and enhance the discipline. In the first part of this paper, a general history of geography within American education is presented. The second part of the paper discusses geography's role within general education at the secondary and tertiary levels, including the academic backgrounds for teachers. The way in which geographic education in the United States provides students with the opportunity to study holistic relationships between people and the environment and its importance to informed citizenship are discussed in the final section of the paper.  相似文献   

9.
开展干旱环境动力学研究的若干问题   总被引:18,自引:1,他引:18  
根据目前干旱环境研究的现状,提出了“干旱环境动力学”的概念及其科学问题提法、研究方法论和研究途径,为干旱环境动力学的建立提供了一个科学框架。干旱环境系统是地球系统的一部分,建立干旱环境动力学,应以地球系统科学的基本原理为出发点。但它应着重研究地球系统科学中十至百年时间尺度干旱环境发展规律和趋势,特别是人类活动在该时间尺度内对干旱环境的影响。为了研究干旱环境问题,自然科学领域的地理科学、生物科学、大气科学、水文和水利以及地质学等必须形态统一的观点和普适的方法论,从而形成相对独立且学科交叉的干旱环境动力学。气候动力学已相对成熟,干旱环境动力学建模可以气候动力学为基础。建模成败的关键是如何将生态过程物理化和化学化,如何建立水文子系统、生态子系统和土壤子系统的数学模型,并与气候动力学模式相互耦合。  相似文献   

10.
Tara A Maddock 《Geoforum》2004,35(2):217-230
Conflicts over water quality regulation are entering local economic development policy and re-shaping political-economic landscapes. Across the United States, decentralizing scales of regulation, scientific uncertainty, and increasing citizen participation are creating new regulatory contexts. Using regime and regulation theory, I address how regulation of the environment is altering economic regimes and creating new alliances among stakeholders. The research shows the dominant regime in the state of Ohio, a pro-growth stakeholder coalition between point source businesses (including electric utilities and municipal sewage treatment plants) and real estate development interests, is fragmenting. At the same time, there is a policy coalition emerging between environmentalists and government staff that is advocating for nonpoint source water pollution regulation. These emergent coalitions exemplify the changing nature of environmental regulation and economic regimes.  相似文献   

11.
西北干旱区SG-SPAC系统水力模型的建立   总被引:8,自引:3,他引:8  
文章论述了西北干旱区水资源的特点,利用现代农田水分研究方法研究了干旱区地表水、地下水、土壤、植物、大气连续体(SG-SPAC)系统的水分转化规律,建立了地表水、地下水和土壤水之间的水力耦合模型,为干旱区的水资源规划、开发和生态环境保护奠定了科学的基础。  相似文献   

12.
史前时代东西方交流及其对人类生产方式变化的影响是备受关注的前沿科学问题。甘青地区是东西方文化交流的关键区域,考古研究显示该地区的跨大陆文化互动始于齐家文化时期(4300~3500 a B.P.)。作为铜石并用时代的重要文化类型,齐家文化早期(4300~4000 a B.P.)至晚期(4000~3500 a B.P.)先民生产方式发生了显著改变。然而,已开展的植物考古研究主要集中在甘肃西部和青海东部,甘肃中、东部的研究相对薄弱,齐家文化时期农业结构的时空变化过程及其影响因素尚不清晰。针对上述问题,文章对甘肃中、东部7处齐家文化时期遗址的植物大遗存进行研究,将其与已有研究结果对比,分析了甘青地区齐家文化时期农业结构的时空差异及其影响因素。结果显示,齐家文化早期,甘青地区东、西部的农业结构均以粟(Setaria italica)为主、黍(Panicum miliaceum)为辅,这可能与粟的高产性和水分利用的高效性等有关;齐家文化晚期,西亚起源的小麦(Triticum aestivum)、大麦(Hordeum vulgare)传入甘青地区,西部的农业结构转变为粟黍农业为主、麦类农业为辅,但甘肃东部依然延续前期以粟黍为主的单一农业结构,这可能源于不同地区对气候趋于冷干的响应程度不同。本研究显示甘青地区齐家文化时期农作物种植结构的时空变化受到史前东西方交流和气候变化与局地环境等因素的共同影响,有助于理解史前东西方交流关键时期和区域人地关系演变的过程与机制。  相似文献   

13.
Sam Ock Park 《GeoJournal》2004,59(1):69-72
Korean modern geography emerged from the dark age of unfortunate Japanese colonial rule after liberation in 1945, and has grown rapidly since the 1960s. Modern geographical theories and methodologies were introduced to Korea by the Korean geographers who received PhD degrees in the United States and returned home to teach at universities in Korea, especially in the 1970s and early 1980s. American geography has influenced the progress of the modern geography in Korea in various ways — education systems, curricula for college students, training graduate students — and research methodologies in Korean geography during the last half-century have been directly and indirectly influenced by American geography. The influence has had, however, both positive and negative effects in the development of Korean geography. There is a tendency in recent years to reinterpret Western theories and concepts in the Korean context, considering distinctive regional and cultural characteristics.  相似文献   

14.
Research on soil fertility is presented in the context of runoff agriculture, a venerable farming system that has been used for millennia in arid to semiarid regions, where water is a major limiting resource for crop production. The agroecology of runoff farming was studied with the Zuni to evaluate nutrient and hydrologic processes, management, maize productivity, and soil quality in some of the oldest recognized fields in the United States. This ancient Southwest agriculture has functioned without conventional irrigation or fertilization by tapping into biogeochemical processes in natural watersheds connected to fields. Carefully placed fields are managed on alluvial fans and other valley margin landforms to intercept runoff and associated sediment and organic debris transported from adjoining forested uplands. We report on research to evaluate and link nitrogen and phosphorus, two key nutrients for crop production, in watershed, soil, and crop components of this agroecosystem. Nutrient data have been collected by observational and experimental methods for each component and the transport of nutrients from watershed to field to maize. The condition of Zuni agricultural soils suggests that their knowledge and management of soils contributed to effective conservation. This study and others indicate the need for further long‐term monitoring and experimental research on watersheds, runoff processes, field soils, and crops across a range of arid to semiarid ecosystems. © 2007 Wiley Periodicals, Inc.  相似文献   

15.
朱力源 《地下水》2019,(3):65-67
解决干旱区水资源缺乏问题必须要从水资源系统配置的角度考虑,虚拟水理念有别于传统的水资源直接配置,通过改变农产品流通格局,进而优化虚拟水流动状态,实现水资源系统配置。结合甘肃省实际情况,在满足"农产品不减收""各地农业用水量不增加"两大约束条件下,以优化算法为工具,搭建了基于甘肃省14个市(州)的以农产品为调控对象的数学模型,调控后,地区总收入呈上升趋势,上升约7%,但农业用水量呈下降趋势,下降约4%。玉米的进口总量上升了9%~10%,而小麦进口总量同比下降了28%~30%。调控方案使虚拟水流动均衡性在当地农业用水综合调控中集中体现,提高了地区水资源系统配置实现的可能性,实现了水资源直接配置和间接调配的综合管理,对缓解干旱区未来社会经济发展中水资源配置面临的问题提出了新的思路。  相似文献   

16.
干旱灾害是制约中国西北地区社会经济发展、农业生产和生态文明建设的重要自然灾害,而且随着气候变暖西北地区极端干旱事件发生频率和强度均呈增加趋势,影响不断加重。"中国西北干旱气象灾害监测预警及减灾技术研究"成果是在数十个国家级科研项目的支持下,经过过去20年的理论研究和应用技术开发所取得的一系列创新性成果。该成果对西北干旱形成机理及重大干旱事件发生、发展的规律取得了新认识,尤其是发现了形成西北干旱环流模态的4种主要物理途径;研制了西北干旱预测的新指标、干旱监测的新指数及监测农田蒸散的新设备,明显提高了干旱监测准确性和针对性;提出了山地云物理气象学新理论,研发了水源涵养型国家重点生态功能区——祁连山空中云水资源开发利用技术;发现了干旱半干旱区陆面水分输送和循环的新规律,揭示了绿洲自我维持的物理机制;认识了干旱气候变化对农业生态系统影响的新特征,建立了旱作农业对干旱灾害的响应关系;开发了旱区覆膜保墒、集雨补灌、垄沟栽培、适宜播期等应对气候变化的减灾技术,为西北实施种植制度、农业布局及结构调整和农业气候资源高效利用提供了科学方案。该成果的完成提升了中国干旱防灾减灾技术水平,培养了中国干旱气象科技队伍,推进了西北地区干旱气象业务服务能力,对西北地区社会经济发展、农业现代化和生态文明建设等方面起到了重要的促进作用。在此基础上,展望了西北地区干旱气象科学研究中迫切需要、有可能突破的主要领域。  相似文献   

17.
Sites of artisanal and small-scale mining (ASM) in sub-Saharan Africa are often places of contestation and dispossession, particularly because mining laws and policies have generally been crafted to foster large-scale mining. This paper builds on research mapping the multiple ways in which ASM is associated with various wrongs – criminality, illegality, immorality, destructiveness - to consider how various, complex gendered relations and place-making practices within mine sites are occluded as a result. We consider these erasures in the context of ASM formalization efforts linked to particular state visions. We note that while negative perceptions of ASM persist, governments, donors and mining companies are increasingly engaging in different forms of negotiation with ASM representatives, particularly through establishing legal ‘ASM zones’ and encouraging or mandating artisanal miners to form associations or cooperatives: processes of formalization. With reference to African case studies, we outline potential issues and challenges in efforts to formalize ASM, while offering insights into how the politics of place-making inform these initiatives. Focusing in particular on the gendering of both the dominant place-making of ASM by policy-makers and regulators and the actual emplaced practices of ASM activities in specific mining sites we highlight the multiple, at times competing and other times overlapping, visions of space at work in this widespread economic activity.  相似文献   

18.
After twenty years of work on the geography of representations, how is it still possible to define geography as “the science of space”, ie as direct knowledge of material reality? This conception of the discipline — based on Cartesian precepts of evidence (eg the observer's independent certainty), reductionism (ie a disaggregation into sets of simple elements), causality (ie the presupposition of a linear linkage between cause and effect) and exhaustiveness (ie the certainty that nothing essential has been omitted) — has been thrown into question by the geography of representations' holistic approach. How can our scientific practices be separated from our interior existence with its affective and emotional aspects? Is not scientific action an extension of being? Mustn't the geographer, above and beyond the observation of concrete phenomena, also understand the subtle and complex — at times random and hidden — links which unite human beings and their life-space, be it from the viewpoint of the poet, or of all those who take alternative approaches to geography? What I would like to demonstrate is (1) how in an historically and socially given environment, the individual constructs his own reality in linking together the structural, functional and symbolic; (2) how the representation of the landscape is related to our existential experience; and (3) how the imaginary and the real are connected in each place.  相似文献   

19.

‘Community geography’ is a growing sub-field that leverages academic resources to facilitate spatial research in partnership with local communities. The Mapping Prejudice Project and the CREATE Initiative, two interdisciplinary projects at the University of Minnesota, demonstrate some of the opportunities and challenges associated with practicing community geography. Mapping Prejudice is leveraging community crowdsourcing to build the first comprehensive spatial database of racially restrictive housing covenants in the United States. CREATE is co-developing research on critical problems at the intersection of environment and equity through collaboration with community partners. These two projects incorporate a methodological commitment to place-based and historically grounded research that seeks to make knowledge in—and in relation to—a specific place. Incorporating earlier feminist and critical GIS theory, these projects have adopted an iterative research model that places under-resourced communities at the forefront of the research process. Their work produces a fluid, responsive, and co-creative approach that has the capacity to legitimate its knowledge claims through responsiveness to community needs and collective experience.

  相似文献   

20.
Beth Greenhough   《Geoforum》2007,38(6):1140-1151
Informed consent has often been presented as a kind of ethical panacea, the best way of guarding against medical and scientific abuses of human rights. However recent empirical research has led bioethicists to question both the feasibility and the value of informed consent procedures. This paper also seeks to critique informed consent, but focuses less on its empirical shortcomings. Instead, this paper questions the assumption that ethics involves engaging in the kind of rational, distanced, objective reflection traditionally considered the basis of both scientific observation and ethical decision making. Drawing on recent insights from ethical geography and geographers studying the biotechnology industry, I wish to argue that ethical reflection is a relational and situated process, less about being distanced and objective, and more about recognizing how our ethical decisions are shaped by our social and material environment.  相似文献   

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