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1.
Four meadows of turtle grass (Thalassia testudinum Banks ex Konig) in Sarasota Bay, Florida were sampled on a bimonthly basis from June 1992 to July 1993 to determine spatial and temporal variation in short shoot density, biomass, productivity, and epiphyte loads. Concurrent with the seagrass sampling, quarterly water-quality monitoring was undertaken at ≥3 sites in the vicinity of each studied seagrass meadow. Three months after termination of the seagrass sampling effort, a biweekly water-quality monitoring program was instituted at two of the seagrass sampling sites. In addition, a nitrogen loading model was calibrated for the various watersheds influencing the seagrass meadows. Substantial spatial and temporal differences in turtle grass parameters but smaller spatial variation in water quality parameters are indicated by data from both the concurrent quarterly monitoring program and the biweekly monitoring program instituted after termination of the seagrass study. Turtle grass biomass and productivity were negatively correlated with watershed nitrogen loads, while water quality parameters did not clearly reflect differences in watershed nutrient inputs. We suggest that traditional water-quality monitoring programs can fail to detect the onset or continuance of nutrient-induced declines in seagrass health. Consequently, seagrass meadows should be monitored directly as a part of any effort to determine status and/or trends in the health of estuarine environments. *** DIRECT SUPPORT *** A01BY074 00029
相似文献2.
《中国地质学会会员单位地质工作诚信评定管理办法（试行）》（简称《办法》）近日发布，旨在更好地服务地勘行业发展，加强地质行业诚信体系建设，开展会员单位的地质工作诚信评定。据了解，《办法》适用于对中国地质学会会员单位的地质工作诚信评定。诚信评定工作遵循“自愿参加、统一评定、公正公平、动态管理”的原则。经评定，符合《办法》诚信评定相应标准的，授予“地质工作诚信单位”，并向社会公布。评定结果与地质行业及相关部门共享互通，发挥协同效应，推进在政府采购、市场准入、资质认定、专项资金补贴、评优评奖、成果转化等工作中的应用。诚信评定不向申报单位收取任何费用。 相似文献
3.
Christopher J. Daughney Matthias Raiber Magali Moreau-Fournier Uwe Morgenstern Rob van der Raaij 《Hydrogeology Journal》2012,20(1):185-200
Baseline monitoring of groundwater quality aims to characterize the ambient condition of the resource and identify spatial or temporal trends. Sites comprising any baseline monitoring network must be selected to provide a representative perspective of groundwater quality across the aquifer(s) of interest. Hierarchical cluster analysis (HCA) has been used as a means of assessing the representativeness of a groundwater quality monitoring network, using example datasets from New Zealand. HCA allows New Zealand??s national and regional monitoring networks to be compared in terms of the number of water-quality categories identified in each network, the hydrochemistry at the centroids of these water-quality categories, the proportions of monitoring sites assigned to each water-quality category, and the range of concentrations for each analyte within each water-quality category. Through the HCA approach, the National Groundwater Monitoring Programme (117 sites) is shown to provide a highly representative perspective of groundwater quality across New Zealand, relative to the amalgamated regional monitoring networks operated by 15 different regional authorities (680 sites have sufficient data for inclusion in HCA). This methodology can be applied to evaluate the representativeness of any subset of monitoring sites taken from a larger network. 相似文献
4.
汉江上游是我国“十五”水环境规划的重点区域之一, 丹江口水库是具有战略意义的重点保护水源.汉江干流和丹江库区现状水质已达Ⅱ类标准, 但因为支流污染严重而形成巨大威胁, 主要污染物COD在“十五”有超标趋势.COD来源以生活源为主, 占77.2%;工业源中制浆造纸业为主要污染行业, COD排量占38.29%.列出了以城镇污水处理厂建设为主体的含A, B, C三种工程项目类型的污染控制方案.实施A类项目需投资27 500万元, 可使汉江上游COD在2005年降至32 682.25 t, 低于基准年1998年的排放水平, 落在省下达的目标总量控制范围内, 保证干流和丹江库区保持Ⅱ类水质; 接踵实施B, C类项目, 可保证其水质稳定达标, 并使支流水质得到明显改善. 相似文献
5.
The relocation of Nigeria's Federal Capital: A device for greater territorial integration and national unity 总被引：1，自引：0，他引：1
Dr. J.C. Nwafor 《GeoJournal》1980,4(4):359-366
As an important feature in the political geography of a country, the location of the capital of a state is of great significance especially as any geographical forces which have affected the political history of a country reach their most intensive expression in the choice of site for the development of the capital city. The decision to relocate it is usually an exceedingly tough one to make and difficult to follow up. In the post-colonial era, Nigeria like many newly independent African States inherited a capital which is central in respect of international trade but eccentric in relation to the country's administrative and cultural hinterlands. Lagos is a typical example. Although the city continues to function as the federal capital, a new site has been selected for its relocation prompted by administrative and political considerations, physical limitations, and the numerous problems resulting from excessive concentration of the nation's resource there. It is hoped that the new site in the country's geometric centre will bring a long-dormant region into effective settlement by spurring a central migration that will open new agricultural frontiers, create a more equitable distribution of population and above all foster the growth of a core region in and around which the state idea could develop. 相似文献
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7.
国家资源环境安全的要素综合评价 总被引：10，自引：0，他引：10
资源环境安全问题始终是世界各国持续发展的核心任务和基本诉求。考虑到单要素和整体两大分析方法的不足，提出一种针对性很强的要素综合分析方法。根据世界上10个人口超过 1亿以上国家的抽样分析表明，土地、水资源、矿产及生态环境的整体状态是决定国家资源环境安全的基本所在。与此同时，为了改善国家，特别是发展中国家的
资源环境脆弱状态和提高其稳定程度，第一是要严格控制人口增长；第二是努力推进本国资源环境开发的国际化进程；第三是增大智力投入以提高资源深度化加工；第四是加大本国生态环境保护力度。 相似文献
8.
As an international problem of continuing significance in the underdeveloped world, population pressure foreshadows the future of many Third World countries. Kenya is one such country. Its deteriorating population-resource balances are set against a limited resource base and a demographically explosive growth rate. Although population pressure has yet to be surveyed fully, landlessness, soil erosion, deforestation, overgrazing and river siltation indicate worsening man-land relationships throughout rural Kenya. In an effort to determine the magnitude and extent of population pressure and to find solutions to its manifold consequences, the Kenya Rural Population Pressure Study will conduct an intensive two year program of research. 相似文献
9.
The U.S. Geological Survey is conducting a national assessment of coal resources. As part of that assessment, a geostatistical procedure has been developed to estimate the uncertainty of coal resources for the historical categories of geological assurance: measured, indicated, inferred, and hypothetical coal. Data consist of spatially clustered coal thickness measurements from coal beds and/or zones that cover, in some cases, several thousand square kilometers. Our procedure involved trend removal, an examination of spatial correlation, computation of a sample semivariogram, and fitting a semivariogram model. This model provided standard deviations for the uncertainty estimates. The number of sample points (drill holes) in each historical category also was estimated. Measurement error in the thickness of the coal bed/zone was obtained from the fitted model or supplied exogenously. From this information approximate estimates of uncertainty on the historical categories were computed. We illustrate the methodology using drill hole data from the Harmon coal bed located in southwestern North Dakota. The methodology will be applied to approximately 50 coal data sets. 相似文献
10.
The National Tsunami Hazard Mitigation Program (NTHMP) Steering Committee consists of representatives from the National Oceanic and Atmospheric Administration (NOAA), the Federal Emergency Management Agency (FEMA), the U.S. Geological Survey (USGS), and the states of Alaska, California, Hawaii, Oregon, and Washington. The program addresses three major components: hazard assessment, warning guidance, and mitigation. The first two components, hazard assessment and warning guidance, are led by physical scientists who, using research and modeling methods, develop products that allow communities to identify their tsunami hazard areas and receive more accurate and timely warning information. The third component, mitigation, is led by the emergency managers who use their experience and networks to translate science and technology into user-friendly planning and education products. Mitigation activities focus on assisting federal, state, and local officials who must plan for and respond to disasters, and for the public that is deeply affected by the impacts of both the disaster and the pre-event planning efforts. The division between the three components softened as NTHMP scientists and emergency managers worked together to develop the best possible products for the users given the best available science, technology, and planning methods using available funds. 相似文献
11.
李文鹏 《水文地质工程地质》2019,(2):1-1
地质灾害隐患和水文地质环境地质调查是自然资源部中国地质调查局九大计划之一,是一项基础性、公益性的地质调查,按调查监测内容不同在全国部署了重要活动构造与区域工程地质调查工程、山地丘陵区地质灾害调查工程、生态脆弱区和特困区水文地质环境地质调查工程、岩溶地区水文地质环境地质综合调查工程、主要含水层水质综合调查工程以及国家地下水监测工程等6个工程。文章简要介绍了该计划自2016年实施以来,各工程在解决基础地质与资源环境问题、服务国家需求、科学理论创新与技术方法等方面取得的进展与成果。 相似文献
12.
中国科学院地质研究所 《地质科学》1982,(2):123-124
在中国地质学会成立六十周年的喜庆日子里,中国科学院地质研究所谨向中国地质学会致以热烈的祝贺,谨向全国广大地质勘测、教学和科研工作者致以热烈的祝贺和亲切的慰问。 相似文献
13.
Primary sand and gravel deposits in Britain play an important role in preserving our cultural heritage and are also a valuable aggregate resource. While an understanding of the extrinsic properties of the soil archive (such as pH, redox, groundwater) can provide a firstorder assessment of the potential risk to any archaeologically sensitive deposits, we have very poor definition of spatial variations in the extrinsic properties of soil that influence archaeological preservation at a regional and national scale. Developments in digital geological mapping, remote sensing, and geochemical survey data undertaken by the British Geological Survey (BGS) have, however, significantly extended capabilities in this respect and can potentially be used to provide a primary assessment of the sensitivity of the present soil archive and the potential risk from changes to the soil process on cultural material in areas earmarked for aggregate extraction. Two of the major factors affecting archaeological preservation—soil acidification and groundwater—can be mapped or predicted at scales of better than 1:50,000 across increasingly large parts of the country using a combination of regional hydrogeological, geophysical, and geochemical data. Additional data from site investigations may further refine preservation potential as a function of changes in redox potential and acidity. These data, maps and models can be used to (1) better establish a baseline for archaeological preservation at a regional and national scale and (2) improve our understanding of how the physical and chemical properties of the near surface environment can be managed to sustainably preserve archaeological materials in areas impacted by sand and gravel extraction. © 2009 Wiley Periodicals, Inc. 相似文献
14.
《Journal of Geochemical Exploration》1997,59(2):123-146
The Forum of European Geological Surveys (FOREGS) includes representatives from 33 European countries and is responsible for co-ordinating Geological Survey activities in Europe. The FOREGS Geochemistry Task Group was established in 1994 to develop a strategy for the preparation of European geochemical maps following the recommendations of the International Geological Correlation Programme (IGCP) Project 259 ‘International Geochemical Mapping’ (now the International Union of Geological Sciences (IUGS) /International Association of Geochemistry and Cosmochemistry (IAGC) Working Group on Global Geochemical Baselines).The FOREGS geochemistry programme is aimed at preparing a standardised European geochemical baseline to IGCP-259 standards. The principal aims of this dataset will be for environmental purposes, as a baseline for the assessment of the extent and distribution of contaminated land in the context of variations in the natural geochemical background, but it will also have applications in resource assessment and for the development of policy for the sustainable management of metalliferous mineral and other resources.The first phase of the programme was the compilation of an inventory of geochemical data based on the results of a questionnaire completed by Geological Surveys and related organisations throughout the FOREGS community. The results show that the sample types which have been used most extensively are stream sediment (26% coverage), surface water (19% coverage) and soil (11% coverage). Stream sediments have been collected using a narrow range of mesh sizes (< 150–< 200 μm), but soil samples have been collected according to two different conventions: some surveys used a similar mesh size range to that used for stream sediments while others employed the < 1000 or < 2000 μm fractions traditionally used by soil surveys. Sample densities range from 1 sample per 0.5 km2 to 1 per 3500 km2. Various analytical methods have been used, but most of the available data have been calibrated using international reference materials, and data for the most important of the potentially harmful elements (PHEs) are available for most datasets. Systematic radiometric data are available for only a small proportion of Europe, a situation which compares very unfavourably with that in Australia, North America, the former Soviet Union and many developing countries.Recommendations are made for increasing the compatibility of geochemical methods between national geochemical surveys as a basis for the preparation of a series of European geochemical maps. The next stage of the FOREGS Geochemistry Task Group will be the collection of the Global Reference Network of samples against which to standardise national datasets according to the methods recommended in the final report of the IGCP 259 programme. 相似文献
15.
2009年是新世纪以来我国经济最困难、挑战最严峻的一年。受金融危机和矿业周期性调整的双重影响,全球矿业经济正处于“一松一紧、震荡调整”的关键时期。国内外矿产勘查投资紧缩,社会投资矿产勘查更加谨慎,矿业形势严峻。这场历史罕见的国际金融危机,给我国地勘业的改革和发展造成巨大困难。如何迎接挑战,化“危”为“机”,正是地勘单位应该认真思考的不二命题。机遇与挑战共存,一是国家政策面的支持,二是国内对矿产资源的需求仍然强劲．三是我国矿产资源潜力巨大．再者就是具备了“走出去”的实力。地勘单位应抓住这难得的发展机会,除了创新地质工作体系．改善外部环境,加强自身建设外,还要善于在国家政策引导下,积极拓展服务领域,发挥人才优势,把地质勘查主业做大做强. 相似文献
16.
S. C. Robinson 《Mathematical Geology》1970,2(4):377-397
Much effort is presently being given in Canada to the development of a national system for storage and retrieval of geologic data. Coordination of these efforts is directed by the secretariat of the National Institute for Geoscience Data under guidance of the Geological Survey of Canada. Most files are project oriented but archival files are justified for data whose observations cannot be repeated, such as those for mineral deposits. Presently, extensive file systems have been created for storage of information obtained in petroleum exploration and exploitation, mineral deposits, field mapping, and geochemistry and geophysics. A Canadian Index to Geoscience Data has been prepared and contains references to all maps and reports, published or unpublished, data banks, and all documents on open file for the federal and provincial agencies.SAFRAS, a general, self-adaptive free-format retrieval and storage system, is employed to retrieve data in plain language. Although geologists are using data systems, it will be the coming generation of geologists who will make maximum use of data processing in geology.presented to the Geological Society of Washington, 8 December 1969. 相似文献
17.
阿尔泰-准噶尔北缘铬铁矿- Cu- Au- Pb- Zn- Ni成矿带主要成矿地质特征及潜力分析 总被引：1，自引：0，他引：1
阿尔泰-准噶尔北缘铬铁矿-Cu-Ni-Au-Pb-Zn-Ni成矿带是全国重点部署找矿勘查工作的16个重点成矿区带之一,是全球阿尔泰巨型成矿带位于中国境内的一部分。文章根据全国矿产资源潜力评价成果,结合新的成矿理论和找矿进展,对该成矿带的边界进行了新的修定;从大地构造演化历史出发,分析总结了该带区域成矿地质背景和有利成矿地质条件,进一步修订了成矿带的成矿谱系;总结了成矿带内次级成矿单元的成矿特征;对带内矿床的主要成因类型和相应的典型矿床的成矿特征进行了总结;分析了成矿带的资源潜力,并在此基础上,确定了Cr、Mo、Cu、Au、Ni、Pb、Zn、Ag为本带下一步勘查部署的主攻矿种,划分了9个远景区,其中3个为重点远景区,6个为一般远景区。此项工作对本成矿区带内下一步矿产勘查工作部署有着重要指导意义和参考价值。 相似文献
18.
海洋生态系统动力学研究与海洋生物资源可持续利用 总被引：22，自引：5，他引：22
围绕国家重点基础研究发展规划（973）项目“东、黄海生态系统动力学与生物资源可持续利用”，介绍了海洋生态系统动力学研究对我国社会与科技发展的意义、研究现状和发展趋势、拟解决的关键科学问题以及实施计划。该项研究的最终目标是弄清我国近海海洋生态系统的结构、功能及其服务与产出，量化其动态变化及生态容纳量，预测生物资源的补充量，寻求可持续开发利用海洋生态系统的途径。使集中多种机制于一体并具陆架特色的我国近海生态系统力学理论体系和研究队伍进行国际先进行列。 相似文献
19.
USGCRP碳循环研究的最新动向 总被引：5，自引：0，他引：5
碳循环研究是国际全球变化研究的热点之一。根据美国全球变化研究委员会提出的“美国全球变化研究计划”(USGCRP),详细介绍了美国碳循环研究的目标、重点研究计划和行动。USGCRP碳循环研究的主要目标是提供碳源和碳汇的综合评价,其重点在于确定北美洲陆地碳汇的数量、位置和成因,通过设立集成观测、过程研究和建模研究的项目来减少其中的不确定性,并提供北美洲陆地碳汇及其变化的更精确估计。USGCRP将从大气、海洋、陆地和人类因素方面结合适当的研究方法,提供多样化的碳循环时空信息,而且提供必要的北美洲陆地碳汇状态的详细描述。在基本反映美国碳循环研究最新趋势的同时,提出了中国碳循环研究应注意的方向。 相似文献
20.
Excessive settlement caused by tunneling during construction often damages adjacent infrastructures and utilities. Such excessive settlement can also present a challenge in the maintenance of subways during their operation. Thus, it is important to be able to accurately predict tunneling-induced settlement. The uncertainties in geotechnical parameters, however, can lead to either an overestimation or an underestimation of the tunneling-induced settlement. Such uncertainties can arise from many sources such as spatial variability, measurement error, and model error; in this paper, the focus is on the geotechnical parameters characterization from site exploration. The goal here is to determine an optimal level of site exploration effort so that effective predictions of the tunneling-induced settlement in clays can be achieved. To this end, a Monte Carlo simulation-based numerical model of site exploration is first established to generate artificial test data. Then, a series of parametric analyses are performed to investigate the relationship between the level of site exploration effort and the accuracy of the tunneling-induced ground settlement prediction. Through the assumed different levels of site exploration effort, statistics of soil parameters are estimated using the maximum likelihood method and the tunneling-induced ground settlement is then analyzed using the probabilistic method, and finally the effect of site exploration effort is assessed. The knowledge generated from this series of analyses is then used to develop the proposed framework for selecting an optimal site exploration program for improved prediction of the tunneling-induced ground settlement in clays. Examples are presented to illustrate the proposed framework and demonstrate its effectiveness and significance. 相似文献