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21.
David Grigg 《GeoJournal》2002,57(4):283-294
Coffee and tea are both drunk in most countries, but typically one predominates. Coffee is the preferred drink in Europe and the Americas, tea elsewhere. Until the early eighteenth century coffee production and consumption was confined to the Islamic world, tea production to East Asia. European traders altered this pattern dramatically. The present pattern of coffee consumption is influenced by income per capita, that of tea is not. Religious influences played some part in the early development of both tea and coffee but have little relevance at the present. National factors have influenced wider patterns. British preference for tea was taken to all their colonies. In recent years fears about health have had some influence on coffee consumption. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
22.
Placing geographies of public health   总被引:6,自引:0,他引:6  
Tim Brown  & Craig Duncan 《Area》2002,34(4):361-369
Following the move to a 'post–medical' geography, a large amount of research has come to focus on public health issues. This paper explores these current geographies of public health and argues for the development of a more critical perspective. In particular, it draws on commentary that has emerged out of debates that have taken place within a body of literature usually identified as the critical 'new' public health. The paper goes on to argue that such scholarship offers crucial insights for the production of a critical geography of public health.  相似文献   
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The sudden and catastrophic, or slow and continuous, release at surface of naturally occurring toxic gases like CO2, H2S and Rn poses a serious health risk to people living in geologically active regions. In general this problem receives little attention from local governments, although public concern is raised periodically when anomalous toxic-gas concentrations suddenly kill humans or livestock. For example, elevated CO2 concentrations have been linked to the death of at least 10 people in the central Italian region of Lazio over the last 20 years, while it was the CO2 asphyxiation of 30 cows in a heavily populated area near Rome in 1999 which prompted the present soil-gas study into the distribution of the local health risk. A detailed geochemical survey was carried out in an area of about 4 km2 in the Ciampino and Marino districts, whereby a total of 274 soil-gas samples were collected and analysed for more than 10 major and trace gas species. Data were then processed using both statistical and geostatistical methods, and the resulting maps were examined in order to highlight areas of elevated risk. General trends of elevated CO2 and Rn concentrations imply the presence of preferential pathways (i.e. faults and fractures) along which deep gases are able to migrate towards the surface. The CO2 and Rn anomalous trends often correspond to and are usually elongated parallel to the Apennine mountain range, the controlling structural feature in central Italy. Because of this fundamental anisotropy in the factors controlling the soil-gas distribution, it was found that a geostatistical approach using variogram analysis allowed for a better interpretation of the data. With regard to the health risk to local inhabitants, it was found that although some high risk areas had been zoned as parkland, others had been heavily developed for residential purposes. For example, many new houses were found to have been built on ground which has soil-gas CO2 concentrations of more than 70% and radon values of more than 250 kBq m−3. It is recommended that land-use planners incorporate soil-gas and/or gas flux measurements in environmental assessments in areas of possible risk (i.e. volcanic or structurally active areas).  相似文献   
26.
Possible refugia for reefs in times of environmental stress   总被引:2,自引:0,他引:2  
This paper investigates the refuge potential of (1) upwelling areas, (2) coral areas at medium depth, and (3) offshore bank and island reefs in a scenario of increased global warming, and thus increased sea surface temperature (SST) and increased solar UV radiation. (1) Observations on coral health and water temperature in the subtropical Atlantic (Eleuthera and Cat Island, Bahamas) and Indian Ocean (Sodwana Bay, South Africa) suggest a link between cool water delivered by upwelling and coral health. After the 1998 bleaching event, caused by strong SST anomalies, coral health and recovery from the previous year's bleaching was significantly better on the narrow southern Cat Island shelf (70% of corals healthy) where the presence of cold water was observed, which was attributed to small-scale upwelling, than on the wide northern Eleuthera shelf (44% of corals healthy), where downwelling of hot bank waters was believed to have damaged corals. In South Africa, regular, short-term upwelling events in five summers reduced SST to well below bleaching level. (2) In the northern Red Sea (Safaga Bay) and in South Africa (Sodwana Bay), wide areas with either coral frameworks or non-framework communities exist. Calculations show that if the top 10 m (20 m) of the ocean became inhospitable to corals, still 50.4% (17.5%) of the coral area would remain intact in the Red Sea and 99% (40%) in South Africa. (3) Offshore bank and island reefs investigated in the Turks, Caicos, and Mouchoir Banks and Grand and Little Cayman showed high rates of mortality and coral diseases. The most remote sites (Mouchoir Bank) were not the healthiest. Refuge areas appear to exist in (1) and (2), but in (3) only if vigorous water-circulation is encountered.  相似文献   
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梭梭荒漠生态系统:Ⅰ初级生产力及其群落结构的动态变化   总被引:12,自引:0,他引:12  
刘晓云  刘速 《中国沙漠》1996,16(3):287-292
通过对梭梭荒漠群落的种类组成、垂直结构、水平结构、季相及梭梭当年生绿色同化枝和草本层的地上植物量的研究,表明在以小半乔木梭梭占主导地位的群落中,丰富的短生植物及长营养期一年生植物均得到较好的发育,说明该群落具有由中亚荒漠向亚洲中部荒漠过渡的性质。而大量单种属或寡种属出现,反映出了梭梭群落具有干旱植物区系的明显特征,与整个新疆植被荒漠植物区系的特征相一致。梭梭群落中建群层片的种类单一,与北疆其它荒漠植被类型相似,而伴生植物的种类组成比其它类型丰富,特别是短生植物及长营养期一年生植物种类较多。初级生产力分别与梭梭当年生绿色同化枝的萌发、生长和脱落,短生植物的迅速生长和死亡,以及长营养期一年生植物的生长有密切关系,分别在5月下旬、6月下旬和8月上旬达到高峰。梭梭当年生绿色同化枝的植物量在其整个群落初级生产力的构成中作用明显。是整个群落初级生产力的72.3%~85.8%。  相似文献   
28.
Assessing rapid environmental change using geoindicators   总被引:1,自引:1,他引:1  
 Geoindicators are high-resolution measures of short-term (<100 years) surface or near-surface changes in earth processes, and phenomena that are significant for environmental monitoring and assessment. They are based on standard concepts and procedures and can be used to track changes in fluvial, coastal, desert, mountain, permafrost and other terrestrial areas. Geoindicators assess both catastrophic events and those that are more gradual, but evident within a human lifespan. Most deal with changes on the landscape (0.1–10 km) and meso-scales (10–100 km), but some, such as relative sea level and volcanic unrest, have regional and global dimensions. Some are complex and costly to measure, others are relatively simple and easy to apply. Geoindicators can also be used to unravel trends over the past few centuries and longer through paleoenvironmental research, thus providing the important baselines against which human-induced and natural stresses can be better understood. Geoindicators have been designed by the International Union of Geological Sciences as an aid to state-of-the-environment reporting and long-term ecological monitoring. Received: 26 July 1996 / Accepted: 1 November 1996  相似文献   
29.
In this study, the relationship between fluorine in drinking water and that in urine of urban residents in China is assessed. Fluorine concentrations in tap water and those in urine show a good correlation with a linear regression coefficient of 0. 9798, indicating that the fluorine concentrations in big cities under investigation are extremely low, and the main source of fluorine is tap water. The weather effect on the intake amount of fluorine is also discussed. When air temperature is above 15℃, people would intake more fluorine through drinking water with the rise of air temperature. When temperature is below 15℃, no remarkable relationship is observed between air temperature and the intake amount of fluorine. This phenomenon indicates that the main source of fluorine in China is tap water instead of foodstuff.  相似文献   
30.
陕西省区域环境地球化学分区   总被引:2,自引:0,他引:2  
为了利用地壳元素分布特征与动植物微量元素含量间的关系,指导生态环境综合治理,借助已有的基础地球化学资料,进行陕西省地球化学分区,确定各分区的环境背景值、污染起始值、缺乏临界值、过剩值临界值,并将陕西省分为陕北、关中、陕南3个地球化学区,圈定了1个元素贫化区和2个元素富集区。提出应该在元素的缺乏和过剩的异常区内进行生物体内微量元素含量的定期检测。做到对地球化学疾病及时发现及时寻找对策,以保证人类生存环境的安全,提高生存质量。  相似文献   
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