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1.
The material flow concept for materials   总被引:3,自引:0,他引:3  
Mineral supply and demand data were used to track the flow of a material from its source through stages of production, processing, and fabrication into the consumption and postconsumption phases. In each stage prior to consumption, the quantity of material lost to the environment or recovered for reuse was determined. In the postconsumption stage, the quantity of material discarded was analyzed to determine how much was disposed to landfills, lost through incineration, or dispersed to the environment. Where the consumption stage involved releases to the environment, as in the use of fertilizer, this was noted also. The material flow studies also strived to determine the amount of recycling that was done in the preconsumption and postconsumption phases. Cumulative historical supply data were used to estimate the total inventory of the materials that have been put into service within the United States, and aggregated consumption data based on end use provided a basis for assessing the cumulative effect of those materials on the environment.Correspondence should be directed to Earle B. Amey, U.S. Geological Survey, National Center 983, Reston, Virginia 20192.  相似文献   

2.
This paper considers the emergence and execution of the concept of the port and industrial zone which has been developed at Fos in the south of France over the last 17 years. From local initiatives the concept was taken over by the national government which, together with a number of multinational companies, has invested heavily in the zone. The third part of the paper attempts to evaluate the concept as a regional manufacturing growth pole in the milieu of French national, EEC, and Mediterranean markets.  相似文献   

3.
政治地理学中生存空间概念的演变   总被引:2,自引:1,他引:2  
生存空间是拉采尔创立现代政治地理学之初提出的核心概念,与国家有机体一起构成人类有机体空间政治的分析框架。20世纪上半叶,地缘政治学派继承并发展了国家有机体的概念,同时吸收了民族主义、社会达尔文主义等思想,将生存空间改造成为服务法西斯空间扩张的理论工具。二战结束后,地缘政治学被唾弃为恶学,而生存空间也被抨击为恶学之钥。80年代后期,新政治地理学从批判视角审视生存空间与法西斯的关系,生存空间的理论价值重新得到重视。论文通过梳理生存空间从提出、兴盛、没落到复苏的发展历程,旨在揭示这一概念在理解政治地理学研究模式、认识人地关系、探索空间治理、制定区域决策等方面的重要价值,为中国未来开展相关研究提供参考。  相似文献   

4.
矿产资源开发中重金属污染问题突出,修复方法的选择至关重要。本文研究和分析了矿区重金属修复的物理修复法、化学修复法和生物修复法,指出了各方法特点。通过分析,提出联合修复、植物修复和新型化学改良剂修复是重金属污染土壤修复的重要方向。  相似文献   

5.
6.
朱宇  林李月  李亭亭  董雅静 《地理学报》2022,77(12):2991-3005
长期以来,“流动人口”和“人口流动”这两个概念、以及基于这两个概念获取的数据在中国相关研究和政策制定中得到广泛使用,甚至主导着中国人口迁移流动的研究。在国际背景下对这两个概念和相关数据的有效性和可靠性进行了深入地检视,并通过对若干人口普查数据和流动人口动态监测调查数据的分析,揭示“流动人口”和“人口流动”在测量人口迁移流动事件时的失效和失真。结果表明,“流动人口”和“人口流动”概念及相关数据已与现实的迁移流动事件和过程严重脱节;它们既可能因高估迁移流动人口的规模而失真,也可能因系统性遗漏某些迁移流动人口(如城—城流动人口)而失效,同时还严重干扰对现实人口迁移流动方向的判断。此外,基于“人户分离”得到的流动人口数据还存在着不能用于“率”指标的计算和缺乏国际可比性等问题。基于此,本文认为中国人口迁移流动的相关概念、测量和数据收集应回归其反映空间变动事件的本质功能,逐步扩大使用基于5年前常住地(乃至1年前常住地)变动的人口迁移流动数据,并充分利用人口登记和行政管理数据开发基于迁移事件的人口迁移流动数据,为分析和判断中国人口迁移流动的演变趋势和规律提供有效且可靠的数据基础。  相似文献   

7.
We investigated the validity of spotlighting techniques for surveying and monitoring desert mammal populations by determining the effect of repeating spotlight transects on the relative precision of density estimates. Precision was modelled by calculating cumulative mean density and associated coefficient of variation. The effect of moonlight at the time of surveying was also investigated. The results show that spotlighting is a valid technique for monitoring some species, however the number of transects required to obtain pre-defined adequate levels of precision is species-dependent. Reasons for these findings are discussed and recommendations for future spotlight surveys for monitoring desert mammal populations are given.  相似文献   

8.
"超级机制"与文化地理学研究   总被引:6,自引:2,他引:6  
超级机制或超机体概念是人类学家提出的概念,后被美国伯克莱地理学派引入到文化地理学研究中。尽管该概念自引入之初起,就伴随着学术讨论,但是它在上个世纪的英美地理学中有着重要的影响。新文化地理学与传统文化地理学的分歧之一也在此概念上。本文列举了在美国和中国文化地理学研究中,超级机制的适用性和局限性,并探讨了超级机制指导下,文化地理学的研究方法在何种情况下是因果分析,何种情况下是非因果分析。进而指出,超级机制概念在分析宏观区域文化一致性上具有解释性,在分析微观尺度区域内的人地关系上也具有一定适用性。新超级机制理论在学术界的讨论过程中提出了一些修正,在分析社会文化时超级机制不适用。  相似文献   

9.
The main development stages of the basin concept: from landscape hydrology to nature management are considered. It is shown that the river, lake and sea drainage basins are the most widespread natural complexes on and surface, with a high degree of integrity and with clear-cut watershed divides having a powerful integrating factor, the water flow. The substantiation is provided for the concepts of the basis as a geosystem, the runoff-producing complexes and the hydrological functions of landscape as well as for the principles of hydrological, water-resources and water-protection regionalization and zoning. On this basis, a classification of hazardous hydrological processes is developed. The structural patterns of the river network within the framework of structural geography are used for indication of the mean long-term discharge and its mapping, and for a classification of river systems according to their size. It is demonstrated that the integrating properties of the water flow permit the basin to be regarded as an integral system entity not only from the perspective of hydrology but also in terms of geomorphology, biogeocenology, landscape geochemistry as well as in complex physical geography as functionally integral natural complexes thereby creating the natural basis for nature management. On the other hand, many basins are socioeconomic and ethnodemographic entities. Ten principles are formulated for the theoretical justification of the basin concept of nature management where the basin is treated as an integral natural and economic system. It is suggested that such an approach should be used in governance of nature management, especially in international basins, as well as in reforming the system of administrative-territorial division of Russia.  相似文献   

10.
The two concepts of “liudong renkou(floating population or FP)” and “renkou liudong(mobility of the floating population or MOFP)”, along with relevant data based on these two concepts, have long been used extensively in China’s research and policy making, playing a central role in Chinese studies of migration. Unlike the concepts of “migrant” and “migration” in the international literature, which are focused on people’s spatial mobility, “liudong renkou” and “renkou liudong” are identified and m...  相似文献   

11.
陈俊岩 《西部资源》2012,(3):153-154
鄂尔多斯的煤炭资源经过多年的开采,给国家经济建设作出了巨大贡献,同时也对生态环境产生了较大影响。本文针对鄂尔多斯地区主要生态环境问题,根据目前煤炭开采技术现状,提出适合鄂尔多斯地区的保水开采技术途径,将矿井水、瓦斯、矸石进行资源化利用。从而实现煤炭开采与生态环境协调发展,促进鄂尔多斯地区煤炭资源合理开发利用。  相似文献   

12.
社会脆弱性概念、分析框架与评价方法   总被引:7,自引:1,他引:7  
社会脆弱性作为脆弱性的维度之一,是脆弱性与可持续性科学研究领域的新兴热点问题.在分析对国内外社会脆弱性研究文献的基础上,从概念内涵、分析框架与评价方法3 方面对社会脆弱性研究进行了评述.目前学者们对社会脆弱性概念有不同的理解,尚未形成统一的概念体系与内涵特征;系统性的社会脆弱性分析框架尚未形成,现有成果多是在脆弱性框架基础上的延伸和拓展,主要从政治经济学视角、社会—生态视角和综合视角开展研究;多元化的评价方法在社会脆弱性的应用研究中仍较少见,已有研究的评价指标体系尚不完善.未来,应进一步拓展社会脆弱性研究内容,促进多学科交叉融合;逐步统一社会脆弱性概念和分析框架,深化社会脆弱性的理论研究;加强社会脆弱性评价方法与指标体系的完善,促进多元化评价方法的应用;加强社会脆弱性减缓与调控对策研究,整合社会脆弱性与适应性框架,为提高社会适应能力与可持续发展提供科学依据.  相似文献   

13.
14.
The article examines the development of city regions with a three-dimensional approach: the city region as concept, object, and practice. The authors base the conceptual, top-down approach on theoretical perspectives from economics, institutionalism, and planning. The understanding of the city region as an object refers both to its territory and its materiality, i.e. population, infrastructure, and landscape. A bottom-up and practice-generated understanding of city-regional development is based on populations’ practising of city regions through everyday mobility, i.e. commuting and shopping, and on the institutional practices related to the spatial organization and responsibility of political bodies, businesses, and civil society organizations. These dimensions and the relations between them are generated and illustrated by an empirical investigation of the emergence of small city regions in Norway. The analysis shows that whereas the economic rationale provides one argument for institutional practices in establishing, naming, and planning city regions in Norway, the common practices of populations do not always coincide.  相似文献   

15.
Modern mining law, by facilitating socially and environmentally acceptable exploration, development, and production of mineral materials, helps secure the benefits of mineral production while minimizing environmental harm and accounting for increasing land-use competition. Mining investments are sunk costs, irreversibly tied to a particular mineral site, and require many years to recoup. Providing security of tenure is the most critical element of a practical mining law.Governments owning mineral rights have a conflict of interest between their roles as a profit-maximizing landowner and as a guardian of public welfare. As a monopoly supplier, governments have considerable power to manipulate mineral-rights markets. To avoid monopoly rent-seeking by governments, a competitive market for government-owned mineral rights must be created by artifice.What mining firms will pay for mineral rights depends on expected exploration success and extraction costs. Landowners and mining firms will negotlate respective shares of anticipated differential rents, usually allowing for some form of risk sharing. Private landowners do not normally account for external benefits or costs of minerals use.Government ownership of mineral rights allows for direct accounting of social prices for mineral-bearing lands and external costs. An equitable and efficient method is to charge an appropriate reservation price for surface land use, net of the value of land after reclamation, and to recover all or part of differential rents through a flat income or resource-rent tax. The traditional royalty on gross value of production, essentially a regressive income tax, cannot recover as much rent as a flat income tax, causes arbitrary mineral-reserve sterilization, and creates a bias toward development on the extensive margin where marginal environmental costs are higher.Mitigating environmental costs and resolving land-use conflicts require local evaluation and planning. National oversight ensures that the relative global avaliability of minerals and other values are considered, and can also promote adaptive efficiency by publicizing creative local solutions, providing technical support, and funding useful research.  相似文献   

16.
食物系统认知进展及其地理学研究范式探讨   总被引:1,自引:0,他引:1  
食物关系国计民生,中国食物系统面临诸多挑战,耕地资源趋减、环境压力临界、农业劳动力流失、消费需求快速转型等对食物系统功能提出更高要求,地理学的综合性和系统性思维为应对这些问题提供了有效的工具和视角。尽管食物系统得到世界银行、联合国粮农组织以及其他国际各方的高度关注,但目前国内对食物系统的研究却严重不足。论文对食物系统的认知进展进行了深入分析,归纳了食物系统的概念认知历程、类型、特征,梳理出食物系统的研究脉络,包括从“概念”存在到“方法”存在、从线性认知到系统认知、从经济活动到食物景观、从现象描述到时空嵌入等,以此凝练出食物系统的核心内涵与认知进展;在科学哲学范式、人地关系范式、空间范式和系统科学范式指导下,论文遵从“格局—结构—过程—机理”由表及里的研究脉络,进一步探讨了食物系统的时空格局、要素结构、演化过程和发展机理,尝试构建了食物系统的地理学研究范式,研究结论旨在为推动食物系统视角基础研究和实践应用提供参考和借鉴。  相似文献   

17.
地理学视角下的独立工矿区研究   总被引:3,自引:0,他引:3  
李倩  张文忠  王岱 《地理科学进展》2013,32(7):1092-1101
独立工矿区是因矿产资源开发而兴起, 以资源开采加工为主导产业, 矿业职工及其家属为居民主体, 远离人口集聚区, 经济社会功能相对独立的区域。独立工矿区作为重要的能源资源供给地, 为国家经济建设和社会发展做出了重要贡献, 但现在却成为当前全国经济发展方式转型过程中不平衡、不协调和不可持续的问题最为集中的地区之一。本文按照“从实践中总结理论”的思路, 基于实地调研资料和既往研究成果, 结合现有界定标准和相关概念的差异, 对独立工矿区的概念进行辨析;并应用经济成长周期、地域生产综合体和演化经济地理等相关理论, 分析了独立工矿区形成和发展的特征和规律, 认为其本质上是资源丰富地区内部与外部系统之间相互作用和协调的结果;独立工矿区未来需以社会、经济和生态环境的协调为目标, 立足其自身属性, 实现多元化发展或特色发展。最后, 对独立工矿区的未来研究方向进行了展望, 主要包括独立工矿区界定标准的量化、资源环境承载力评价、地域功能演化机理研究和可持续发展模式的探讨。  相似文献   

18.
地理大数据挖掘的本质   总被引:5,自引:3,他引:5  
针对地理大数据的内在本质以及地理大数据挖掘对于地理学研究的意义,本文解释了地理大数据的含义,并在大数据“5V”特征的基础上提出了粒度、广度、密度、偏度和精度等“5度”的特征,揭示了地理大数据的本质特点。在此基础上,从地理大数据的表达方式、地理大数据挖掘的目标、地理模式的叠加与尺度性、地理大数据挖掘与地理学的关系等4个方面阐述了地理大数据挖掘的本质与作用,并从挖掘目标的角度对地理大数据挖掘方法进行分类。未来地理大数据挖掘的研究将面临地理大数据的聚合、挖掘结果的有效性评价以及发现有价值的知识而非常识等几方面的挑战。  相似文献   

19.
Sediment geochemistry and testate amoebae (thecamoebians) were used to track the spatial extent and temporal evolution of mine loading and its impact on aquatic biota in Lake Pyh?j?rvi, central Finland. Pyh?salmi is an operating Zn-Cu–S mine, located by Lake Pyh?j?rvi. Mine loading to the lake comes mainly from wastewater. Highest metal loading occurred in the 1970s and 1980s. Present loading consists mainly of Ca and S that nearly saturate dense wastewaters with gypsum. This affects oxygen concentration in the lake’s northern basin, where effluent is presently discharged. Of 25 short sediment cores retrieved from Lake Pyh?j?rvi, 10 came from sites ‘downstream’ and 15 from ‘upstream’ of the mine. Three sample levels from each core were selected for further investigation after exploratory XRF metal analysis. Samples were chosen to represent lake conditions before the mine impact, during the peak impact phase, and at present. Results from pre-disturbance deposits show that the two lake basins are naturally different. The ‘downstream’ basin (Junttiselk?) has lower oxygen and a higher sedimentation rate, which was revealed by concentrations of redox-sensitive and clastic-related elements, as well as faunal distributions. The peak mine impact is reflected in the high concentration of S and metals Cu, Zn, Cd, Pb, which spread widely in the lake and increased > 100% at sites near the tailings area. These concentrations have since decreased, but not to pre-disturbance levels. The faunal response to peak metal concentrations was weak, spatially limited and masked by larger responses to other environmental factors, including eutrophication, oxygen concentration, and increased clastic input generated by land-use changes. These environmental factors and changes in mine water composition probably account for the reason that faunal assemblages did not return to the pre-mine situation. Instead, the modern fauna reflects a third assemblage type that developed after the peak-loading phase. Geochemical and thecamoebian analyses show that the mine has affected the two basins of the lake differently during the lake history. Results suggest that mining impacts could be mitigated with good planning and management.  相似文献   

20.
城市网络韧性的概念与分析框架探析   总被引:4,自引:0,他引:4  
城市网络作为一种新的城市地域系统组织形式和研究范式被广泛关注。目前绝大多数城市网络研究都基于正面视角,对城市网络的负面效应、安全与可持续发展问题却鲜有提及。论文通过梳理城市网络与区域韧性的相关研究进展,探索性地提出一种基于演化韧性的城市网络韧性概念来探讨城市网络的“负面问题”。城市网络韧性可理解为城市网络系统借助于城市间社会、经济、工程与组织等各领域的协作和互补关系,能够预防、抵御、响应和适应外部急性冲击和慢性压力的影响并从中恢复或转换的能力。基于此概念,结合演化韧性与适应性循环理论,将城市网络视为一个动态演化的复杂适应系统,基于基础设施、组织、经济与社会等4个维度,兼顾适应性与适应能力,尝试性地提出基于韧性特征和韧性过程视角的城市网络韧性综合分析框架,并对城市网络韧性的分析方法、优化方法予以展望,对涉及的若干核心问题展开讨论。研究可为以安全发展为目标的区域规划、区域政策制定和区域组织建立提供科学依据,也可为各城市节点找准自身角色、有效参与区域治理提供有价值的参考。  相似文献   

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