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51.
BOOK REVIEWS     
Books reviewed in this article: Aerial Photography and Remote Sensing. Terrain Analysis and Remote Sensing . JOHN R. G. TOWNSHEND , ed. Environmental Data Use in Computer-assisted Data Handling Systems: The Results of a Survey of Applications in the Pacific Northwest States . KENNETH E. GORDON . Applied Land Use: A Spatial Approach . JOHN F. LOUNSBURY , LAWRENCE M. SOMMERS , AND EDWARD A. FERNALD , eds. The Second Battle of New Orleans: A History of the Vieux Carre Riverfront-Expressway Controversy . RICHARD O. BAUMBACH , JR. AND WILLIAM E. BORAH . Cultural Environmental Archaeology . MYRA SHACKLEY . The Immoral landscape: Female Prostitution in Western Societies . RICHARD SYMANSKI . life Among the Poor in Cairo . UNNI WIKAN , translated by Ann Henning. Women, Work and Property in Northwest India . URSULA SHARMA . The Domestication of Women: Discrimination in Developing Societies . BARBARA ROGERS Economic Optimization in Locational and Transport Analysis . A. G. WILSON , J. D. COELHO , S. M. MACGILL , H. C. W. L. WILLIAMS . New Tools for Economic Development: The Enterprise Zone, Development Bank, and RFC . GEORGE STERNLIEB AND DAVID LISTOKIN , eds. Regional Wage Inflation . R. L. MARTIN , ed. Finding A Place For Energy-Siting Coal Conversion Facilities . FRANK J. CALZONETTI WITH MARK S. ECKERT . Environmental Management, Resources, and Systems Environmentalism. Second Edition . T. O'RIORDAN . Countryside Conservation . BRYN GREEN . Medical Spatial Diffusion: An Historical Geography of Epidemics in an Island Community . A. D. CLIFF , P. HAGGETT , J. K. ORD , AND G. R. VERSEY . Philosophy and Geographic Thought Order and Skepticism: Human Geography and the Dialectic of Science . RICHARD SZYMANSKI AND JOHN A. AGNEW . Measurement of Subjective Phenomena . D. F. JOHNSTON , ed. Conceptions of Space in Social Thought: A Geographic Perspective . ROBERT DAVID SACK . The Association of American Geographers: The First Seventy-five Years: 1904-1979 . PRESTON E. JAMES AND GEOFFREY J. MARTIN . The Life and Thought of Isaiah Bowman . GEOFFREY J. MARTIN . Physical River Basin Planning: Theory and Practice . SURANJIT K. SAHA AND CHRISTOPHER J. BARROW , eds. Soils and landforms: An Integration of Ceomorphology and Pedology . A. I. GERRARD Climatic Change and Society. Consequences of Increasing Atmospheric Carbon Dioxide . WILLIAM W. KELLOGG AND ROBERT SCHWARE . Political Political Redistrictings and Geographic Theory . RICHARD L. MORRILL . Population Studies in Spanish American Population History: Dell Plain Latin American Studies NO. 8 . DAVID J. ROBINSON , ed. Population Redistribution in the Midwest . CURTIS C. ROSEMAN , ANDREW J. SOFRANKO , AND JAMES D. WILLIAMS , eds. Geographical Perspectives on the Elderly . A. M. WARNES , ed. Regional Perspective On the American South . MERLE BLACK AND JOHN SHELTON REED , eds. The Prairies and Plains: Prospects for the 80s . JOHN R. ROGGE , ed. Rural Rural Settlement in an Urban World . MICHAEL BUNCE . Social Accident at Three Mile Island: The Human Dimensions . DAVID L. SILLS , C. P. WOLF , AND VIVIEN B. SHELANSKI , eds. The American Small Town: Twentieth-Century Place Images . JOHN JAKLE . Urban A House of My Own . SUSAN LOBO . The City: Patterns and Processes in the Urban Ecosystem . CHRISTOPHER H. EXLINE , GARY L. PETERS , AND ROBERT P. LARKIN . Movement in Cities . P. W. DANIELS AND A. M. WARNES . Urbanization and Urban Planning in Capitalist Society . MICHAEL DEAR AND ALLEN J. SCOT , eds.  相似文献   
52.
王治安 《地质与勘探》2023,59(3):533-544
巴隆河西金矿床是东昆仑金成矿带近年来新发现的金矿床,其形成时代、地质特征与矿床类型尚不明确。本次在详细野外地质调查的基础上,通过构造-蚀变填图、锆石U-Pb定年和综合对比等方法,研究巴隆河西矿床的成矿特征和岩体侵位时代,以确定该矿床的成因类型与成矿时代。构造-蚀变填图发现巴隆河西矿床的金矿化赋存于花岗质岩体的9条构造蚀变带,明确了5个金矿体呈带状分布于北西西向断裂中,揭示金矿化与高岭土化、褐铁矿化、硅化和黄铁矿化等蚀变密切相关。赋含金矿化的花岗闪长岩和花岗斑岩的锆石U-Pb定年结果表明,其侵位时代分别为202.5±1.8 Ma和222.1±1.1Ma,属于印支晚期,约束了巴隆河西金矿的形成时代。结合区域岩浆活动时限、巴隆金矿地质特征、矿体产状与中低温矿物组合特征,提出巴隆河西矿床为造山带型金矿,推断逆断层及其伴随的热液活动是巴隆河西矿床金元素活化、迁移和富集的关键因素,指出北西西向构造蚀变带是该区带金矿成矿的有利部位。  相似文献   
53.
This study was conducted to investigate technical and socio-political attributes that lead to the underperformance of two selected irrigation schemes (Shina and Bebeks) in the Lake Tana floodplains, Ethiopia. Irrigation application efficiency (AE) at nine experimental fields showed a wide range, from 20 to 80%, but was mostly between 40 and 60%. Irrigation water-use efficiency (IWUE) varied from 1.9 to 7.2 kg m?3 for onion and 0.9 to 1.2 kg m?3 for maize. The lined and earthen canal conveyance losses in Bebeks were 0.037 and 0.047 l s?1 m?1, whereas in Shina they were 0.033 and 0.044 l s?1 m?1, respectively. The overall consumed ratio (OCR) of water was 0.58 for Bebeks and varied from 0.73 to 1.2 in Shina. Both schemes are performing below the standard based on technical performance indicators. Irrigation water user associations (WUAs) were not implemented, but irrigation committees (ICs), composed of local political leaders, are managing both schemes. Canal and reservoir sedimentation from erosion of upstream catchment areas during the rainy season was the major problem.  相似文献   
54.
生态系统完整性评价研究进展   总被引:14,自引:0,他引:14  
张明阳  王克林  何萍 《热带地理》2005,25(1):10-13,18
系统地介绍了生态系统完整性概念的由来,以及对生态系统完整性进行评价的指标必须满足的原则;并从指示物种,结构-功能-组成,压力-响应等方面介绍了生态系统完整性评价指标;进一步介绍了生态系统完整性等级的划分;对目前生态系统完整性评价研究中存在的问题进行了初步的讨论。  相似文献   
55.
In the Archaean Pilbara Craton of Western Australia, three zones of heterogeneous centimetre- to metre-scale sheeted granites are interpreted to represent high-level, syn-magmatic shear zones. Evidence for the syn-magmatic nature of the shear zones include imbricated and asymmetrically rotated metre-scale orthogneiss xenoliths that are enveloped by leucogranite sheets that show no significant internal strain. At another locality, granite sheets have a strong shape-preferred alignment of K-feldspar, suggesting magmatic flow, while the asymmetric recrystallisation of the grain boundaries indicates that non-coaxial deformation continued acting upon the sheets under sub-solidus conditions. Elsewhere, randomly oriented centimetre-wide leucogranite dykes are realigned at a shear zone boundary to form semi-continuous, layer-parallel sheets within a magma-dominated, dextral shear zone.

It is proposed that the granite sheets formed by the incremental injection of magmas into active shear zones. Magma was sheared during laminar flow to produce the sheets that are aligned sub-parallel to the shear zone boundary. Individual sheets are fed by individual dykes, with up to 1000s of discrete injections in an individual shear zone. The sheets often lack microstructural evidence for magmatic flow, either because the crystal content of the magma was too low to record internal strain, or because of later recrystallisation.  相似文献   

56.
本文以河北省万全县为例, 探索在GIS 和RS 技术支持下进行区域生态安全综合评价的 方法。数据包括1992 年8 月的TM影像、2002 年8 月的ETM+和SPOT 影像、1∶5 万DEM等; 选取 植被指数变化、土地利用类型变化和土壤有机质含量变化三类动态评价因子; 采用综合指数法构 建了基于生态退化的动态评价模型; 应用最小二乘原理客观地计算出了模型中各指标的权重; 并最终在ArcGIS 9.0/Spatial Analyst 模块中生成了生态安全评价图, 使模型得以实现。结果表明 该县南部河川区生态安全要优于中部丘陵区和北部山区; 相对不安全区域占到全县总面积的 50.1%, 虽然不安全区域总体分布较为散落, 但在北部和中部相对集中; 总体生态安全评价值为 2.3, 标志着本地区的生态安全级别较低, 应引起当地政府的高度重视。另外, 采用动态评价因子, 比采用静态评价因子具有一定优势; 采用最小二乘原理计算模型中权重系数的方法比较实用和 科学, 降低了人为影响因素, 也可以避免主观判断产生的错误, 为评价模型中权重系数的确定提 供了一种新的方法和选择。  相似文献   
57.
This article details the process of integrating models to answer a specific policy-driven question: ‘What could be the impact of proposed Natural Water Retention Measures (NWRMs) on Europe’s Green Infrastructure (GI)?’ It describes the new Land Use Modelling Platform (LUMP), now enabling a high spatial scale (100-m) and large coverage (pan-European), whereby several sector-specific models contribute to assessing the impact of regional-level policy on a given spatial topic of concern. The configuration (land claims and land allocations modules) and calibration (accessibility and biophysical suitability) of the LUMP are explained. Four NWRM scenarios (riparian areas, afforestation, grassland and baseline scenario) are configured to run the simulations. For the reference: year 2006, the spatial representation of GI is based on land-use features of a refined version of the CORINE Land Cover (CLC), and resumed as connected components made of nodes and links.

Mathematical morphological image processing and network graph theory model, available from the free software package GUIDOS (the Joint Research Center of the European Commission), enabled the measurement of the GI connectivity and identified most critical links. Results show that the competition for land claimed by different economic sectors, combined with policy-driven rule-sets for the implementation of different NWRMs, yields very different results for the 2030 land-use projections, and subsequently for the morphology of GI. Three indicators associated with the morphology of GI are computed in order to assess the model outputs for 2030. The indicators are computed to answer the following questions: (1) How is the quantity of GI affected by each of the NWRM, and what proportion of that GI is most valuable? (2) What is the location of the most critical nodes and connectors of GI, and what land-use conversions occur under these? (3) Are the average components getting larger or smaller?

Whereas the grassland measure results in the largest net increase of GI, the afforestation measure results in the overall largest number of hectares of key nodes and links within the network. Land conversions occur under the critical GI nodes and links, with a large increase in agricultural areas, especially for the riparian measure under critical nodes and the grassland measure under critical links. Also predominant is the swapping of land from pasture to forest under critical links with the afforestation measure. The riparian measure most increases the average size of GI components, and all three measures contribute to bridging two large components which were divided in the 2006 land-use map, thus increasing the size of the largest component by more than 50%.  相似文献   
58.
连续5年对青岛海豚表演馆中北太平洋宽吻海豚(Tursiops gille Dall)进行现场实验和行为学研究,获取了大量的生理指标数据,运用不同的分析和计算方法对所得数据进行了筛选、剔除及处理,确立了海豚各生理指标的正常闽值和范围确定的方法,从而为准确了解海豚机体的生理状况、疾病诊断及治疗奠定了基础。  相似文献   
59.
The Sonneratia apetala artificial mangroves in the intertidal zone of Da Wei Bay at Qi’ao Island of Zhu-hai, South China were chosen as the macrofauna succession plots while bare tidal flats of the same size were established as control plots in surrounding interference-free areas. Conventional change indicators of community structure, such as biomass and biodiversity, and indicators, such as exergy and specific exergy, which reflect the information change of overall communities, were used to analyze the succession of macro-fauna communities inS. apetala artificial mangroves. The similarities and differences in variation tendency of the different ecological indicators and their reflected ecological principles were compared. The results showed that from D-1 to D-1275 after plantingS. apetala, the biomass of the macrofauna communities first increased, which was then followed by an increase in the network relationship between the macrofauna communities (analysis of the Pielou evenness index and Shannon-Wiener diversity index). The system in-formation (specific exergy) increased the slowest. Between D-1460 and D-2370 after plantingS. apetala, there was a decrease in biomass, network structure, and system information in the succession plots. After the decrease in the system information (the specific exergy), there was a decline in the network relationships (Pielou evenness index and Shannon-Wiener diversity index). Biomass was the last indicator to decrease. The similarities and differences among the different ecological indicators varied during the succession pro-cess, which reflected the relativity and differences among the indicators. This study suggested that, although the species diversity index can be an effective indicator of two types of changes (network structure and system information), it was quite clear that species diversity measurement was not suitable for expressing the changes in biomass during the succession process. While exergy and specific exergy can provide useful information  相似文献   
60.
To develop indicator–based management tools that can facilitate sustainable natural resource management by non–specialists, meaningful participation of stakeholders is essential. A participatory framework is proposed for the identification, evaluation and selection of rangeland condition indicators. This framework is applied to the assessment of rangeland degradation processes and sustainable natural resource management with pastoralists in the southern Kalahari, Botswana. Farmer knowledge focused on vegetation and livestock, with soil, wild animal and socio–economic indicators playing a lesser role. Most were indicators of current rangeland condition; however 'early warning' indicators were also identified by some key informants. This demonstrates that some local knowledge is process–based. Such knowledge could be used to improve indicator–based management tools and extension advice on the livelihood adaptations necessary to prevent or reduce ecological change, capable of threatening livelihood sustainability. There is evidence that social background influences indicator use. Communal farmers rely most heavily on vegetation and livestock indicators, whilst syndicate and land–owning pastoralists cite wild animal and soil–based indicators most frequently. These factors must be considered if indicator–based management tools are to meet the requirements of a diverse community.  相似文献   
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