世界数字化磁异常图的编制技术

世界数字化磁异常图是建立全球地球物理场的基本图件之一,编制该图件旨在服务教学、工业与科学研究,其全球覆盖性使得世界范围的地球科学对比研究与系统研究成为可能.深入认识该图件的数据来源、处理过程、分辨率与可靠性分布,有利于正确与合理地使用该图件与数据.因此,笔者首先介绍了世界磁异常图的研究背景、科学意义与发布形式,其次阐述了编图的基本原则,归纳与分析了编图的相关技术,然后描述了目前的编图进展,最后总结了编图的瓶颈、难点与不合理之处,并且相应地提出了编图的改进措施,期望为我国将来的世界磁异常数据汇编提供参考资料.     

Political ecology in North America: Discovering the Third World within?

Political ecologists working in many other parts of the world are now heading north, or simply going global, posing a series of important questions related to theory, methodology, politics, and policy along the way. This special issue, contains papers originally delivered at a conference held at Rutgers University in 2003 that addressed this phenomenon. The papers collected offer case studies that reveal the First World as subject to a host of processes that can be insightfully understood via a political ecology perspective. First, globalized production and consumption regimes have created new linkages that demand synoptic analyses of often far-flung research sites. Second, the painful coincidence of deindustrialization and a radical restructuring of agricultural credit and price support systems have devastated North American and European heartlands, effectively producing “Third World” conditions in many depressed rural areas. Third, migration streams originating in Latin America, Africa and many parts of Asia have brought sizable Third World populations into the spatial heart of capitalism. Fourth, the belated recognition of some indigenous claims to resources, especially in Canada, and fierce opposition to others, have reopened questions of (internal) colonial domination. Finally, we see the burgeoning First World political ecology literature as the culmination of what Louise Fortmann has called “the long intellectual journey home” for many scholars who originally carried out research on/in the Third World. All of these factors have combined to help political ecologists discover suitable analytical terrain in the First World.     

Heritage and landscape change: Recording,archiving and engaging with photogrammetry on the Jurassic Coast World Heritage Site

The Jurassic Coast World Heritage Site is a landscape defined by change and process. As such, the approach to its heritage must be similarly flexible and active. A balance must be found between celebrating these processes of change, whilst also conserving those invaluable discoveries and features that so define this coast, as well as encouraging ongoing research and public engagement. This delicate task can be aided firstly by thinking about this geologically defined World Heritage Site as a landscape. In this way it is possible to develop rich and nuanced narratives between the human and geological. Secondly, by embracing new technologies and methodologies to record, archive and communicate features and finds, as well as the process of change itself. Here, we explore these ideas through two unique sites of geological and palaeontological interest discovered in the process of quarrying. To balance keeping the sites open to the public with the risk of natural and human damage to the sites, Structure-from-Motion photogrammetry was used to create accurate, high-resolution, georeferenced 3D models. The process and potentials of the technique are discussed, alongside a discussion of the broader ideas of heritage and approaches already at play on this coastline.     

稀土资源储备刻不容缓

本文基于全球稀土资源供需形势和我国储量减少的趋势分析了我国开展稀土资源储备的紧迫性.从储备规避“世贸规则”进行间接控制出口、增强在国际稀土市场的话语权以及降低国家外汇储备风险三个方面阐明了我国开展稀土资源储备的必要性.通过借鉴美国和日本在稀土矿产地和矿产品储备方面的成功经验,结合我国稀土资源储备现状,初步构建了适合我国...     

澳大利亚昆士兰地区地形地质图的数学基础探讨

通过WGS-84坐标系、通用横轴墨卡托投影原理和实际应用的介绍,对澳大利亚昆士兰地区地形地质图的数学基础进行初步探讨,掌握利用MapGIS制作外国地形地质图的过程和方法,为拓展地质找矿空间打下基础。     

Movement patterns of surf-zone fish species in a subtropical marine protected area on the east coast of South Africa

A long-term mark-recapture study was used to assess the movement patterns of surf-zone fishes in the St Lucia Marine Reserve, a marine protected area within the iSimangaliso Wetland Park, a World Heritage Site on the east coast of South Africa. Between 2001 and 2013, 6 613 fish from 71 species, caught by hook and line, were tagged at four sites within and adjacent to a no-take marine sanctuary area. A total of 1 004 (15.2%) recaptures were made from 17 species. The majority (82.4%) of these species displayed station-keeping behaviour, whereas only three were classified as wider-ranging species, and no species with discernible migratory behaviour was observed. Findings for five species with the highest recapture rates, namely Pomadasys furcatus, Epinephelus andersoni, E. marginatus, Dinoperca petersi and Lutjanus rivulatus, are presented in greater detail. Recapture rates ranged from 7% to 50% and time at liberty from 0 to 3 163 days. Individuals of all five species displayed station-keeping behaviour, with the 95th percentile of intra-study-site movements varying between 200 and 1 025 m (linear distance). However, four of the five species also displayed some ranging behaviour and made exploratory excursions ranging from 3.5 to 125 km, in both northerly and southerly directions. The dominance of station-keeping behaviour suggests that the St Lucia Marine Reserve sanctuary zone provides an important refuge for these species, with some export to adjacent areas.     

Exposure to extreme climate decreases self-rated health score: Large-scale survey evidence from China

High temperature is a growing threat and impacts public health through different exposure mechanisms. Our study constructs a comprehensive exposure measurement based on temperature variability, duration, and effective influence range. We investigate human responses to high temperatures through self-rated health scores based on individual-level data from China Labor-force Dynamic Survey (CLDS). Results show that higher temperature and temperature variability significantly decrease self-rated health scores. Subjective health risk is most significantly related to the cumulative temperature in the previous two weeks. We also find that the exposure effects at night and on weekdays are more severe. Workers who experience greater exposure from commuting and work environments are negatively impacted by high temperatures. In addition, men, the elderly, middle and low education groups, rural residents are more likely to be impacted by high temperatures.