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61.
B.F. Iyun 《GeoJournal》1998,44(2):129-139
The viewpoint that most health problems are environmentally related has always been promoted by medical geography. In recent times, concern about environmental degradation has been of high priority for many national and international organizations as ‘we human beings become a threat to our planet’. There is also a need to specifically focus attention on the impact of so-called development efforts on the health of women and children, in particular those living in highly marginalized regions which often contribute substantially to the overall development of their countries. This paper uses the concept of vulnerability as a departure point from which to map the health risks to children in Igbekun area of Ondo State, the ‘transgressive muddy’ oil-rich coastal area of Nigeria. The paper attempts to highlight the poor quality of life and health of children in particular, and how it is becoming much more difficult to practice health intervention programmes, especially oral rehydration therapy (ORT) in the area. The Igbekun area is an unhealthy and harsh environment, complicated by the devastating effects of oil drilling in recent years. The siltation and sedimentation of the creeks and lagoons have serious health dimensions as human faeces float in and around villages because the ‘bush toilets’ can no longer be reached. The on-going environmental crisis has also deprived women of their traditional means of livelihood; fishing. There is a relatively high level of ignorance (compared with other women living in the same local government area (LGA) of causes of the commonest diseases such as diarrhoea, acute respiratory infection (ARI) and measles. A majority of the women have never heard of family planning, immunization against diseases and interventions such as ORT. Promotive health care services, especially those that strive to reduce the high mortality of children have passed the mothers by. It is also becoming impracticable to promote ORT because of the widespread ‘salty and oily’ water supply in the area. The greatest concern of the women now is that oil drilling activities have further amplified their stressful conditions especially their health and that of their children. Unfortunately, their plight is not acknowledged by the Nigerian authorities and the oil companies are least concerned about alleviating the poor health status of the community, in particular the most vulnerable groups, children under the age of five. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
62.
Three provenances ofPappophorum caespitosum, a forage native grass from the temperate arid region of Argentina, were studied to gain a physiological knowledge of the seasonal organic N status in response to adequate water supply and water stress conditions; and to assess the extent to which variations in the N status between these provenances arise under different water regimes. Plant part samples were analysed for free and bound organic N fractions. Water shortage resulted in a significant depression of plant growth in all provenances. Total N concentration declined along the annual cycle in both water treatments, but it was higher under water stress. The size of the free N pool was very large, suggesting that it may act like an osmoticum. Nitrogen use efficiency increases along the growing period, while the rate of N intake and the specific leaf N content decrease. Variability was found between provenances in most of the physiological and biochemical traits examined under both water regimes.  相似文献   
63.
The paper examines the prospects for resource-based development in the Russian Far East. It adopts a critical perspective on the potential for resource-based development by examining problems with Far East resource industries, specifically by looking at the experience of the other resource economies more generally. In particular, it highlights the new geo-economic context for resource development in the Far East of Russia as the world economy approaches the much touted, and now questioned, ‘Pacific Century’.  相似文献   
64.
本文初步总结了市场经济国家的商业性地勘工作主要特点,对我国今后开发商业性地勘地作所要解决的问题做了探讨,并就冶金地质队伍如何更好地适应今后商业性地质工作提出了建议。  相似文献   
65.
Geothermal resource assessment is the broadly based appraisal of the quantities of heat that might be extracted from the earth and used economically at some reasonable future time. In the United States, the Geological Survey is responsible for preparing geothermal assessments based on the best available data and interpretations. Updates are required every few years owing to increasing knowledge, enlarging data base, improving technology, and changing economics. Because geothermal understanding is incomplete and rapidly evolving, the USGS complements its assessments with a broad program of geothermal research that includes (1) study of geothermal processes on crustal and local scales, (2) regional evaluations, (3) intensive study of type systems before and during exploitation (4) improvement of exploration techniques, and (5) investigation of geoenvironmental constraints.  相似文献   
66.
本项研究是PMIP(PalaeoclimateModelingIntercomparisonProject)国际合作项目中有关模型模拟与观测资料对比的一部分。模型试验对象是6000yr.BP的全球湿润状况。模拟试验以检测太阳辐射变化对全球大尺度气候系统的影响为主要目的。观测资料是利用地质证据恢复的古湖泊水位变化,实际上是某一地区的有效降水(降水减蒸发)的变化。通过两者的比较发现,所有模拟试验均能重现6000yr.BP在亚洲南部与非洲北部的湿润环境,从而证实了因太阳辐射变化导致的亚洲与非洲季风的增强。但模拟的季风增强无论是强度还是范围均小于地质记录。原因很可能是模拟试验中下垫面特征用“现代”的来处理。模拟试验对北半球夏季辐射增加造成的西风带北移及由此引起的中纬度地区的气候变化不够成功。绝大多数模拟对受洋流与海温影响较大的地区是失败的。主要原因可能是所有PMIP中的模拟试验都未考虑海洋的作用。  相似文献   
67.
Surface hydrological studies are seen as inadequate in hyperarid and arid areas to provide reliable estimates of recharge. In most such areas surface discharges are not present so that assessments of groundwater resources are dependent upon ground interpretation and denied the flow control found in assessments elsewhere. Groundwater models show that gradients are sustained by long-term dewatering and very small amounts of modern indirect recharge. Recharge indications are well within the error of a hydrological balance. Discharges appear equally small. The development of groundwater in arid areas frequently faces problems of salination due to recycling of irrigation water and rising groundwater heads. Abstraction is often inadequately managed so that uncontrolled mining of groundwater occurs. The advantage that groundwater has, however, is that it offers staged development and staged appraisal.  相似文献   
68.
The soil freeze–thaw controls the hydrological and carbon cycling and thus affects water and energy exchanges at land surface. This article reported a newly developed algorithm for distinguishing the freeze/thaw status of surface soil. The algorithm was based on information from Advanced Microwave Scanning Radiometer Enhanced (AMSR‐E) which records brightness temperature (Tb) in the afternoon and after midnight. The criteria and discriminant functions were obtained from both radiometer observations and model simulations. First of all, the microwave radiation from freeze–thaw soil was examined by carrying out experimental measurements at 18·7 and 36·5 GHz using a Truck‐mounted Multi‐frequency Microwave Radiometer (TMMR) in the Heihe River of China. The experimental results showed that the soil moisture is a key component that differentiates the microwave radiation behaviours during the freeze–thaw process, and the differences in soil temperature and emissivity between frozen and thawed soils were found to be the most important criteria. Secondly, a combined model was developed to consider the impacts of complex ground surface conditions on the discrimination. The model simulations quite followed the trend of in situ observations with an overall relation coefficient (R) of approximately 0·88. Finally, the ratio of Tb18·7H (horizontally polarized Tb at 18·7 GHz) to Tb36·5V was considered primarily as the quasi‐emissivity, which is more reasonable and explicit in measuring the microwave radiation changes in soil freezing and thawing than the spectral gradient. By combining Tb36·5V to indicate the soil temperature variety, a Fisher linear discrimination analysis was used to establish the discriminant functions. After being corrected by TMMR measurements, the new discriminant algorithm had an overall accuracy of 86% when validated by 4‐cm soil temperature. The multi‐year discriminant results also provided a good agreement with the classification map of frozen ground in China. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
69.
Multivariate AZTI's Marine Biotic Index (M-AMBI) was designed to indicate the ecological status of European coastal areas. Based upon samples collected from 2009 to 2012 in the Bohai Bay, we have tested the response of variations of M-AMBI, using biomass (M-BAMBI) in the calculations, with different transformations of the raw data. The results showed that the ecological quality of most areas in the study indicated by M-AMBI was from moderate to bad status with the worse status in the coastal areas, especially around the estuaries, harbors and outfalls, and better status in the offshore areas except the area close to oil platforms or disposal sites. Despite large variations in nature of the input data, all variations of M-AMBI gave similar spatial and temporal distribution patterns of the ecological status within the bay, and showed high correlation between them. The agreement of new ecological status obtained from all M-AMBI variations, which were calculated according to linear regression, was almost perfect. The benthic quality, assessed using different input data, could be related to human pressures in the bay, such as water discharges, land reclamation, dredged sediment and drilling cuts disposal sites. It seems that M-BAMBI were more effective than M-NABMI (M-AMBI calculated using abundance data) in indicating human pressures of the Bay. Finally, indices calculated with more severe transformations, such as presence/absence data, could not indicate the higher density of human pressures in the coastal areas of the north part of our study area, but those calculated using mild transformation (i.e., square root) did.  相似文献   
70.
One of the reasons for the failure of some Marine Protected Areas (MPAs) is the lack of respect for their boundaries and regulations, which intensifies the need to assess the attitudes of stakeholders affected by MPAs. To this end, it is necessary to know the perception and behavior of resource users in these areas in relation to the management process. This study addressed the perception of different groups of fishermen in three MPAs that allow sustainable use of resources on the Brazilian northeastern coast. The perception analysis was based on four aspects: biodiversity conservation, flexibility and adaptability of fishermen, participation in management and opinions about the MPA. The interviewed fishermen (n=100) were classified into natives or immigrants,≥than 40 years old or <40, predominant use of selective or nonselective fishing gear and part or full time fishermen. The results showed that younger fishermen and the ones who use selective fishing gear presented a more conservation prone perception; nonselective fishermen and part-time fishermen were more flexible and adaptable to changes; and younger fishermen tended to agree more with the establishment of the MPAs. Taking these differences in perceptions among fishermen into account could serve as a basis for improvements in the management and conservation of fishing resources, besides helping predict possible future behavior due to changes in management policies.  相似文献   
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