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71.
The article examines the role of ‘local paths’ and ‘substrates’ (networks, stakeholders, and human and economic capital) in the revitalization strategies of shrinking cities. Relationships between local stakeholders as well as their initiatives to revitalize declining cities determine not only future decision-making but also the demographic, economic, environmental, and social evolution of those cities. The article analyses two medium-sized declining cities in the old industrial region of Asturias, Spain. After a presentation of the processes that led to the studied cities' rise and decline, their revitalization strategies are analysed and interpreted on the basis of the local stakeholders' role. In these cities, the impact of local factors may largely explain the uneven evolutionary path in each city following crisis in their respective leading industries.  相似文献   
72.
Interventions to reduce farmers’ vulnerability to crises rarely build on existing coping strategies. Emergency seed aid offers a unique opportunity to examine links between different types of interventions and local coping mechanisms, as such relief has been abundant and long-term. This study focuses on farmers’ use and assessment of crisis assistance within Ethiopia, where seed aid delivery dates back at least 34 years. Farmers’ abilities to strategize and negotiate inter-/intra-seasonal variability are not being addressed by current supply-driven approaches. Lessons derived from seed aid give insights toward more effective practice for programs aiming to bolster farmers’ resilience in high-stress and uncertain contexts.  相似文献   
73.
Recent work at FLK North (FLK N) has unearthed a new archaeological assemblage recovered with precise control of its stratigraphic position. In the present work, the technological study of the new lithic sample is described. The results show the co-occurrence in the same site of different technological behaviors. At FLK N, hominins were involved in both percussion/battering activities and, through freehand and bipolar knapping, in core reduction. However, the reconstruction of the operational sequences shows that core reduction was probably a marginal behavior, while percussion/battering activities occurred more regularly throughout the sequence. If hominins were not involved in regular carcass processing, as recent taphonomic studies suggest, then hominins' sporadic and low-impact visits to the site over a long period of time must have been driven by other activities probably linked to the exploitation of alternative resources. Plant processing could have been a plausible explanation for hominin presence at FLK N.  相似文献   
74.
This article examines the interplay of gender, caste‐religion, and household survival strategy formation among Christian and Muslim fisher folk in the south Indian state of Kerala. The methodology consisted of surveys of forty‐one households in two villages in which data pertaining to male and female work patterns and other household level data were collected in the summer of 1999. My analysis demonstrates how particular ideologies of gender and work associated with different caste‐religion communities influence the strategies individual households adopt. I discuss intersections between gender and caste‐religion with other socioeconomic factors and illustrate the manner in which gender then gets reworked in particular ways in the course of economic transformation.  相似文献   
75.
Book Reviews     
Books reviewed: Arne, Kalland and Gerard, Persoon (eds) Environmental Movements in Asia M., Kellman and R., Tackaberry Tropical Environments: The Functioning and Management of Tropical Ecosystems Gavin, Daws and Marty, Fujita Archipelago: The Islands of Indonesia From the Nineteenth‐Century Discoveries of Alfred Russel Wallace to the Fate of Forests and Reefs in the Twenty‐First Century Nihal, Perera Decolonizing Ceylon: Colonialism, Nationalism and the Politics of Space in Sri Lanka  相似文献   
76.
张照志 《地质与勘探》2023,59(1):188-210
矿产资源储量家底是一个国家的基础根基,矿产资源及矿产品(含重要工业产品)是一个国家实施工业化及促进现代化建设的物质基础,是一个国家综合国力的体现。要以科学的精神,评价矿产资源。有多少家底,办多大事情,一步一个脚印地支撑国家经济建设。本文在回顾1949年新中国建立以来70余年地质矿产资源勘查、矿产资源开发利用及工业化取得了举世瞩目的成就的基础上,对自1952年以来中国矿产资源国情调查与评价历史进行系统评价,经综合集成研究,总结提出中国矿产资源国情调查与评价的发展演变规律,所得出的研究结论与认识对于推进我国矿产资源国情调查与评价工作具有一定的现实意义。研究认为:矿产资源在我国工业化与经济社会发展中发挥着重要作用,基于中国矿产资源储量管理体制及职能的变化,以矿产资源储量管理为核心,将中国矿产资源国情调查与评价的发展演变阶段划分为5个时期:启动期(1952~1965年)、规范期(1966~1993年)、改革期(1994~2006年)、发展期(2007~2017年)与深化期(2018年-),阐述了各时期的特点与发展演变规律,以及查明资源储量和矿产品的变化规律。在每个时期,我国均依靠国家力量,组织...  相似文献   
77.
分析了保障网络GIS信息安全的必要性和网络GIS信息可能受到的安全威胁及其物理入侵点,提出了保障网络GIS信息安全的技术策略。  相似文献   
78.
A comparison of stygofauna communities inside and outside groundwater bores   总被引:6,自引:2,他引:6  
Sampling stygofauna is both time consuming and labour intensive. The challenge is to get samples from as many bores as possible within a limited time. The essential assumption for this is that faunal communities inside bores are comparable and representative of the communities outside.To compare relative abundance, taxonomic richness and community composition of the fauna inside groundwater bores to the fauna of the surrounding aquifer, 20 monitoring bores in Palatinate, southwestern Germany, were sampled twice in 1 month. Initially, a sample of 4 l of water was collected from the bottom of each bore. A further sample of 51 l was collected from the groundwater surrounding the bore using a pneumatic piston pump with double packer sampler.Water chemistry inside and outside the bore was similar, but the relative amounts of sediments within the bores were higher compared to those from outside. Relative abundances of fauna inside the bores were higher than in the aquifer, but taxonomic composition was similar with the exception of the proportions of nematodes and amphipods, which were higher inside. As a result, the proportions of cyclopoids were lower inside. Higher nematode proportions are explained partially by the nearly complete extraction of bore sediment. A “habitat heterogeneity effect” states that in heterogeneous aquifers with few suitable habitats, faunal distribution is supposed to be extremely patchy. Thus, detritus accumulates in bores, attracting animals and providing “habitat islands” in the groundwater. This effect could explain the higher amphipode proportions inside the bores, which were generally more frequently populated than the surrounding groundwater. As a consequence, fauna is thought to be nearly absent from groundwater, where suitable habitats are lacking. In those sparsely populated aquifers, samples representative of the aquifer taxonomic richness and composition can only be collected by removing large volumes of water, or by sampling the bottom of bores. These findings also suggest that the use of unbaited colonisation chambers or traps in the groundwater, which are comparable with bores, would seem to be a promising approach.  相似文献   
79.
国际数学地质协会2005年会(IAMG2005)于2005年8月在加拿大多伦多召开。大会主题为“地理信息系统与空间分析”,下设空间分析、地质统计学、空间信息和综合应用等四个主题,共25个专题分会场。围绕空间信息主题下的“E-geoscience:支撑地球科学活动的数字化基础设施”、“管理和开发地球科学遗产”、“野外地调系统和分布式传感网络”、“地学研究机构中的信息管理策略”等四个专题,介绍了会议活动情况和与会论文内容及研究课题。这大致可以反映当前地球科学领域数据支持的研究现状和发展趋势,尤其是在野外地调新技术、数据遗产整理开发、数据基础设施建设和专题数据管理应用等方面的研究。  相似文献   
80.
滑坡灾害防治的新技术路线及分析   总被引:6,自引:1,他引:6  
论文指出了滑坡灾害防治中面临的工程问题和科学问题。提出了“监测为首、排水为主、结构为辅、预测预警、科学决策”新的滑坡防治技术路线,介绍了其涵盖的基本内容。监测的首要性在于山体地质结构的复杂性和具体滑坡的个体行为。通过监测有可能获得地质体当前的状态、提高排水工程的可靠性、确定工程治理适用范围、创造滑坡灾害预测预报的条件、为科学决策提供依据;排水不仅可以预防滑坡灾害的发生,还应作为工程治理的主要措施。它以较低的成本维持山体的整体强度;与排水技术相比,借助于工程结构治理大型滑坡,是以较高的代价换取山体局部区域的强度提高;滑坡灾害的预测预警和科学决策,依赖于科学监测数据和可靠的分析方法。新技术路线的可靠性、合理性和实用性还需更为全面深入的论证,对相关问题开展讨论,有助于提高我国滑坡灾害防治水平。  相似文献   
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