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1.
我国直接为农业服务的磷、硫、钾矿资源总体形势不容乐观。针对各自资源特点,应采取不同的发展战略:磷——立足国内,有进有出,南出北进;硫——立足国内,适当进口,调整结构,必要储备;钾——稳定进口,国外开发,国内开发,国内找矿,四位一体,分三步走。为此建议:将磷、硫、钾纳入战略性矿产资源的范畴进行管理和规划;强化地勘队伍,加大找矿力度;增加投入,寻求新的突破;加大“走出去”的步伐;规范进出口秩序;国家在更高的层面进行宏观调控;拓宽为农业服务的新领域。  相似文献   

2.
封闭体系有机质与有机碳氢氮恢复动力学研究   总被引:3,自引:0,他引:3  
在封闭体系的条件下,对典型的Ⅰ、Ⅱ、Ⅲ型干酪根在热演化过程中的损失进行生烃动力学研究,获得了Ⅰ、Ⅱ、Ⅲ型干酪根的总量、有机碳、氢以及氮质量损失动力学参数。用Kinetics软件计算了封闭体系干酪根有机碳丰度、氢碳原子比和氮碳原子比的恢复系数。认为在对高成熟—过成熟干酪根进行生烃评价时,Ⅰ、Ⅲ型干酪根残余有机碳丰度需要进行恢复,而Ⅱ型干酪根残余有机碳丰度不需要恢复。三种类型干酪根的氢碳原子比均需要进行恢复。  相似文献   

3.
Landslide risk: some issues that determine societal acceptance   总被引:2,自引:1,他引:1  
This paper illustrates approaches to landslide risk acceptance in various parts of the world in the context of the willingness to accept that risk, the willingness to pay to reduce the risk, and the willingness to alter the environment in the process. These factors are interlinked using the ternary ??willingness diagram?? which is also used to demonstrate how such willingness may change over time and to compare a range of generic approaches to landslide remediation as well as different conceptual approaches to landslide risk management. The willingness construct is intended to provide a readily understood framework for infrastructure owners and operators, amongst others, to understand how their approach to risk management compares with those in other regions, countries and contexts. Issues relevant to the response of society and groups of individuals to landslide risk, its acceptance and management include cultural factors, regulation and planning, budgetary constraints, vehicular vulnerability, and the often limited size of the event footprint compared to the vulnerability shadow that is cast are also discussed.  相似文献   

4.
基岩裂隙水探寻是一项意义重大的研究课题,富水优势断裂的确定是其中的关键。文章详细论述了运用层次分析法寻找富水优势断裂并进行分级的实施方法。这一方法的实施可归纳为"两个前题条件,五个分析步骤,一个结果判断",两个前题条件为富水性功能分类和构建优势指标体系,五个分析步骤为构建层次分析结构模型、构造判断矩阵、层次单排序及其一致性检验、层次总排序、对象层权重总排序;一个结果判断为利用层次分析的结果进行断裂富水性分级,从而最终确定出富水优势断裂。此法为富水优势断裂的定量化评价提供了一种简洁、实用的新方法。   相似文献   

5.
《International Geology Review》2012,54(11):1042-1050
Minerals of the stibnite-antimonselite series, in close association with tiemannite, clausthalite, kullerudite, Se-bearing stibioluzonite, native gold, quartz, and barite, were discovered in Cambrian stratabound gold deposits at La'erma and Qiongmo, western Qinling, China. Based on S/(S + Se) ratios of microprobe analyses, the binary stibnite-antimonselite system is divided into four series: stibnite, Se-stibnite, S-antimonselite, and antimonselite. Micro-hardness of the stibnite series (Sb = 58.47 to 72.99 wt%, S = 11.86 to 28.76, and Se = 0.00 to 29.12) and the antimonselite series (Sb = 48.94 to 59.13 wt%, Se = 29.20 to 46.86, S = 1.99 to 11.43) is 101.26 and 103 kg/mm2, respectively. Representative reflectivities of the four series are (470 nm) Rg'= 42.62 to 47.62%, Rp' = 30.83 to 40.55%; (550 nm) Rg' = 41.84 to 46.75%, Rp'= 31.48 to 38.85%; (590 nm) Rg' = 42.25 to 46.63%, Rp' = 30.73 to 39.46%; (650 nm) Rg' = 43.30 to 46.48%, Rp' = 30.01 to 41.56%. Cell parameters obtained from two stibnite samples (containing 3 to 5% Se) are a = 1.1209 to 1.1212 nm, b = 1.1299 to 1.1303 nm, c = 0.3847 to 0.3849 nm; and those of S-antimonselite and antimonselite are a = 1.1591 to 1.1593 nm, b = 1.1724 to 1.1747 nm, and c = 0.3941 to 0.3984 nm.  相似文献   

6.
地勘单位要吸引和留住人才,就要在事业、感情、待遇留人上下功夫.即营造鼓励人才干成事业、帮助人才干好事业、创造施展才华的社会氛围和环境;用来自领导的关心爱护之情,同事的团结友爱之情来拴住人心;为人才提供与其创新能力和贡献相适应的物质待遇,使人才充分享有实现自身价值的自豪感、贡献社会的成就感、得到社会承认的荣誉感.  相似文献   

7.
湖南省探矿权、采矿权市场现状与发展对策   总被引:1,自引:0,他引:1  
探矿权、采矿权市场是社会主义市场经济的重要组成部分.培育和规范探矿权、采矿权市场不仅是实现矿产资源利用方式和管理方式转变的根本途径,更是推动矿业经济全面开放。走向健康有序发展的强大动力.湖南省的探矿权、采矿权市场还不发育,与我国市场体制的发展进程和其他各类市场的建设进程相比,很难适应入世的需要.在对湖南省探矿权、采矿权市场现状进行深入分析的基础上,提出了解放思想、整顿秩序、明确政策、加强勘探。严格规划、加强领导等项措施来培育和规范我省探矿权、采矿权市场.  相似文献   

8.
科学和工程研究被计算、信息和通讯技术的持续进步推动着,被今天自身研究增加的复杂性、范围和尺度的挑战拉动着。数字计算、数据、信息和网络以及计算机模拟技术的应用,正在形成替代和拓展理论/分析、实验/观察2个经典的研究方法去创建新的学科的趋势。近来多种趋势表明一个如何创造、传播和存储科学和工程知识更伟大、更迅速的真正变革即将到来,美国应当把握这个机遇、承担责任,去整合和拓展数字革命的成果,服务于下一代的科学和工程研究及相关教育。高端计算机网络共享系统的关键在于将数据、信息、工具、仪器,包括超级计算、存储以及交流等综合性的知识资源完全服务于具体的研究群体,提供新的途径,使研究人员在发现和探索研究上获得更多更好的信息,使得研究小组跨时间、区域、部门甚至学科间实现共享和协作。坚持美国学术研究团体所使用的高端科学计算必须是最先进的,国际科学基金会与其它适当团体机构间的合作应该为创造和维持现代数据驱动科学研究所必需的重要数据资料档案库负主要责任2个原则,并通过建立NSF内部组织、科学和工程组织来保障系统的实施。这是美国国家科学基金会(NSF)信息基础设施(Cyberinfrustructure)高级咨询组的报告《通过信息基础设施促进科学和工程的革命》的主要内容。   相似文献   

9.
中下扬子区二叠系露头层序地层研究   总被引:15,自引:1,他引:15  
按新近国际年代地层划分方案(ICS,2000),下扬子区二叠纪地层自下向上分为3统,9阶和相对应的华南传统6阶划分。二叠系从阿瑟尔阶至长兴阶(44Ma)共划分出14个三级层序,每个三级层序平均时限约为3.14Ma,其中“紫松阶”)相当阿瑟尔+2/3萨克马尔阶)1个(船山组中上部)、“隆林阶、(相当1/3萨克马尔阶+阿丁斯克阶)2个(分别对应船山组上部和梁山组或镇江组)、“栖霞阶”(相当库班甘德阶+1/3罗德阶)3个(栖霞组),“茅口阶”(相当于2/3罗德阶+沃德阶+卡皮丹阶)4个(孤峰组,茅口组,堰桥组,银屏组和武穴组),吴家坪阶2个(龙潭组或吴家坪组),长兴阶2个(长兴组或大隆组);共归并为4个层序组(sequence set)。  相似文献   

10.
This paper explores the ways that Mongolian pastoral-nomadic herders and supporting aid organizations anticipate, interpret, and respond to dzud, a form of winter storm that prevents livestock grazing and often results in large-scale herd deaths. Analysis is drawn from organizational reports, government speeches, and mass media that have been collected to give a complex, multi-faceted understanding of the collection, distribution, and interpretation of data pertaining to the social and scientific construction of this natural hazard. Using critical discourse analysis, this study asks how herder perspectives and needs have been incorporated into reports and action plans of international development organizations. The collected documents provide insight into the ways that knowledge is constructed, disseminated and valued among policy makers, development planners and herders. Additionally, the findings indicate disagreement between stakeholders as to when to declare a national emergency, and how to best help herders respond to the increasing frequency of dzud. While some organizations rely on traditional recovery mechanisms, others have turned to technological solutions, all aiming to assist herders in adequately responding to and recovering from one dzud before another occurs. From the analysis of policy proposals, this study aims to understand and inform the ways that international development programs, government officials, and herders work to preserve pasturelands and herding lifestyles threatened by dzud.  相似文献   

11.
富钴结壳的壳层在形成过程中因环境不同而产生结构构造与物质成分的差异。选取采自中太平洋海山、具有多层构造的富钴结壳(样品号MHD79)进行分析。观察到其下部磷酸盐化壳层和上部未磷酸盐化壳层各有3层,即致密层、较致密层和疏松层,且其发育顺序呈镜像关系。元素化学分析显示:Sr、Pb含量由下到上表现为由高到低再到高,同样呈镜像分布,指示结壳生长过程中,古海洋生产力由高逐渐降低,又逐渐升高。在受强烈磷酸盐化作用影响的壳层中,由致密到疏松,其渗透性由弱到强,导致磷酸盐化由弱到强。在未受强烈磷酸盐化影响的壳层中,S i、A l、Ti、V元素含量与结壳显微构造的疏松或致密相关性不强,而是主要受控于结壳中包含的碎屑成分含量。由老到新S i、A l、Ti、V含量逐渐增加,可能是由于随着MH海山逐渐靠近亚洲大陆及青藏高原逐渐隆起,陆源物质供应逐渐增加的结果。  相似文献   

12.
An integrated physicochemical and hydrogeochemical assessment was carried out at an automobile junk market in Obosi and in residential areas in Anambra State, south-eastern Nigeria to examine the concentration of heavy metals in the groundwater and determine the quality of the water for drinking and other domestic purposes. Forty groundwater samples were collected from boreholes and hand-dug wells (three samples from Obosi and the rest from Onitsha). They were subjected to atomic absorption spectrometry using standard field and laboratory techniques and analysed for physicochemical and hydrogeochemical parameters. Results show that the groundwater in the study area is slightly acidic to neutral, soft to moderately hard when compared with the World Health Organization maximum allowable concentration values and the Nigerian Standards for Drinking Water Quality. The electrical conductivity, dissolved oxygen and biochemical oxygen demand ranged from 58 to 1796 μS/cm, 6.78 to 8.76 and 0.17 to 1.50 mg/L, respectively. Heavy metal concentrations measured (in ppm) in the water included nickel, manganese, copper and zinc and varied from 0 to 1.82, 0 to 0.195, 0 to 0.325 and 0 to 0.09, respectively, while heavy metal concentrations in the soil measured (in ppm) included iron, lead and cadmium and varied from 0 to 3.87, 0 to 1.80 and 0 to 7.38 mg/kg, respectively. Statistical results gave significant correlation (at 0.05) between electrical conductivity and total hardness, biochemical oxygen demand and dissolved oxygen, and several others elements. The study helps in the understanding of the chemistry of groundwater for long-term monitoring and management for the local community.  相似文献   

13.
水质模型研究进展与流域管理模型WARMF评述   总被引:12,自引:0,他引:12       下载免费PDF全文
分析了以地表水、地下水与非点源为代表的水质模型研究发展历程,揭示了水质模型由经验-机理、单要素(或无机、大量、无毒要素)-多要素(或有机、微量、有毒要素)、单介质-多介质、稳态-动态、点源-非点源-两者统一研究、饱水带-包气带-二者统一研究、小规模分散(河流、湖泊、地下水等)-大规模集成(整个流域)、理论研究-实际应用研究的发展特点。认为当前水质模型正处于由水质研究向以水质为中心的流域管理研究转变的关键时期,给出了一个流域管理新模型WARMF的介绍与特点分析。  相似文献   

14.
According to the latest International Chronostratigraphic Scheme (ICS, 2000), the Permian in the Middle-Lower Yangtze region of South China can e divided into three series and nine stages relevant to the traditional six stages of South China. From Assellian to Changxingian of Permian, 44 Main age range, the strata are composed of 14 third-order sequences, each of which is 3.14 Ma in average age range. There is one third-order sequence of Zisongian, equivalent to middle and upper Chuanshan Formation or equal to Asselian and two thirds of Sakmarian. There are two third-order sequences, corresponding to Liang-shan Formation or Zhenjiang Formation and upper Chuanshan Formation, which are assigned to Longlingian, coinciding with Artinskian and one third of Sakmarian. In addition, three third-order sequences, equal to Qixia Formation, are attributed to Chhsian, corresponding to Kubergandian and one third of Roadian. Four third-order sequences, comprising Gufeng, Maokou, Yanqiao,Yinping and Wuxue formations, are assigned to Maokouan, equivalent to two thirds of Roadian, Wordian and Capitanian. Two third-order sequences, equal to Longtan Formation or Wujiaping Formation, are included in Wuchiapingian. Other two third-order sequences, corresponding to changxing Formation or Dalong Formation, are assigned to Changhsingian. In brief, these above third-order sequences can be incorporated into 4 sequences sets.  相似文献   

15.
土地利用变化对全球气候影响的研究进展与方法初探   总被引:10,自引:0,他引:10  
综合分析了土地利用与土地覆盖变化(LUCC)对全球气候影响研究的重要科学问题和国内外研究现状,在此基础上,考虑各学科的相互交叉、渗透和耦合等特点,提出并初步设计了土地利用变化对全球气候影响研究的星地一体化LUCC—气候—生态系统耦合研究技术方法体系,并就土地利用变化对全球气候影响的LUCC演变规律及动力学机制、LUCC...  相似文献   

16.
王登红 《中国地质》2016,(5):1585-1598
华南是中国近百年内矿产资源开发强度比较高的地区,形成了赣南钨矿、桂北锡矿、湘南铅锌矿等一大批老矿山。随着已探明资源的快速消耗,"深地"探测、深部找矿已是大势所趋。基于对华南不同地区、不同类型、不同企业矿山生产情况的了解,文章对矿产资源的深部探测问题,从探测的目标、理论、深度、程度、效益等诸方面加以探讨,认为:当前技术经济条件下,1坚持国家目标、科学目标和人才目标相结合的原则,宜灵活运用各种成矿理论,充分发挥"五层楼+地下室"等勘查模型的作用,把"层状含矿地质体"作为矿产资源深部探测的主要目标;2坚持从已知到未知和由浅入深的原则,重点在老矿区和浅部地质与矿产资源比较清楚的工作程度比较高的地区优先部署工作,既可以降低风险又可以满足现实需要;3宜坚持点面结合的原则,2000 m、3000 m乃至于5000 m深钻的部署,宜相应地部署在矿床、矿田和矿集区工作程度最高的地区,达到立体探测和"透明化"的目的;4坚持综合评价的原则,综合调查、综合评价、综合研究,学科也要综合,避免单打一,避免单学科冒进。以问题为导向,具体问题具体分析,注意合理的探测深度和工作程度,抓住关键,有针对性地布设工作量,才能取得成效。  相似文献   

17.
Zhang  Jiquan  Okada  Norio  Tatano  Hirokazu  Hayakawa  Seiji 《Natural Hazards》2004,31(1):209-232
Agro-meteorological hazards such as drought, waterlogging and cool summer occur with very high frequency and affect maize production and social-economic development in the maize-growing region of Songliao Plain, China. Moreover, both the frequency of these hazards and loss from them are considered to be increasing with global warming. The purpose of this paper is to quantitatively analyze the relationships between the fluctuation of maize yield and drought, waterlogging and cool summer, and to evaluate the consequences of these hazards in the maize-growing area of Songliao Plain, taking Lishu county as a case study area based on GIS (Geographic Information System). Crop yield-climate analysis and regression analysis were employed to analyze and quantify relationships between the fluctuation of maize yield and drought, waterlogging and cool summer, and to evaluate the consequences of these hazards. The parameters and model of damage evaluation were presented using weighted comprehensive analysis, and the degree of damage of drought, waterlogging and cool summer to maize production was comprehensively evaluated and regionalized. It is shown that from 1949 to 1990, the negative value years of the fluctuation of maize yield due to meteorological hazards accounted for 55% of seasons, of which 14% was caused by drought, 30% by waterlogging, 4% by cool summer and drought, 9% by cool summer and waterlogging, 13% by drought and waterlogging, 30% by drought, waterlogging and cool summer. Studies on the instability and spatial variation of the fluctuations in maize yield in Lishu county showed that the middle plains are stable areas to climatic influence, while southeastern hills and low mountains, the low lands of the plains along the East Liao River and the western plain are unstable areas in terms of areas in maize yield. The synthetic index of the degree of damage to maize of drought, waterlogging and cool summer showed a strong positive correlation with the ratio of the amount damaged to the normal yield of maize. This suggests that this index can be used to evaluate such damage. The degree of damage of drought, waterlogging and cool summer to maize in Lishu county shows the regional characteristics, which increase gradually from the center to the west and east, this being almost identical with the spatial distribution of the fluctuation of maize yield due to these hazards. This study can be expected to provide the basis for developing strategies to mitigate agro-meteorological hazards and reducing the losses from them, and adjust the medium and long-term distribution of agricultural activities so as to adapt to environmental changes.  相似文献   

18.
Using methods to estimate the value of environmental goods seems to be essential for economic planning and moving toward development. In this paper, using methods of discrete payment vehicle (dichotomous choice), i.e., single-bounded and Double-Bounded Dichotomous Choice, the value of air pollution in Tehran and households’ willingness to pay to improve air quality, in four selected regions (Shahr-e-Ray, Shoosh, Haft-e-Tir and Tajrish) is estimated and the corresponding results of these two techniques were compared. The results showed that the total value of air quality improvement, calculated through two techniques of Double-Bounded and Single-Bounded Dichotomous Choice were, respectively, 2,398,657,500 and 1,492,566,000 thousands Rials (1USD = 35,000R) in a year and weighted mean of each citizen’s willingness to pay to improve air quality, calculated through these two methods was estimated to be 282,192 and 175,596 Rials in a year, respectively. Considering the annual damage to health, for any 1% increase in pollutants and yearly cost of pollution reduction which are, respectively, 1,199,000,000 and 7,336,000,000 thousands Rials, it was determined that citizens’ willingness to pay through two methods includes 20 and 30% of the cost of pollution control, respectively, while 70% of pollution is due to mobile sources. However, citizens’ low willingness to pay is attributed to citizens’ distrust of government policies as well as their ignorance of the harmful effects of air pollution. In general, the results of this study, with regard to the cost of pollution from Single-Bounded Dichotomous Choice are closer to actual market conditions.  相似文献   

19.
Based on the questionnaire survey, this paper analyzes China’s public perception of climate change in terms of several influence factors and some empirical findings are obtained. We find that some respondents are willing to take individual actions to address climate change, and they pay more attention to climate change or approve that climate change does harm to residents and society; meanwhile, they tend to have confidence in the government to deal with climate change or believe that fiscal and taxation policies are the effective policy measures. However, there are also other respondents unwilling to take actions and argue that climate change proves the natural consequences. Thus, in order to motivate the public to take actions, the paper suggests that the government should widespreadly disseminate relevant knowledge about climate change to the public and guide the work to address climate change and adopt proper fiscal and taxation policies.  相似文献   

20.
In the growing field of Geoheritage, Geoconservation, Geo-education and Geotourism, there is a need to manage sites of geoheritage significance. While there is some great geology in nature available to appreciate for scenic value, education, tourism and research, many locations need to be protected from people and commercialism (e.g. the Iridium layer at the K/T boundary in Gubbio, Italy, the Ediacaran fauna in South Australia, the Burgess Shale in Canada or the zircon crystals at Jack Hills, among many others), and some locations need hazard management to protect people (e.g. continuously collapsing cliffs that have potential to be hazardous via rock falls, or slippery slopes, or high cliffs that are treacherous, or ‘king waves’ on rocky shores). The concept of the ‘8Gs’ is intended as a policy-style guidance that logically and progressively links Geology and Geoheritage through a series of steps to Geo-education and Geotourism. There is a logical progression from Geology the Science, through to Geoheritage and the identification of sites of geoheritage significance, to the establishment of Geosites/Geoparks, Geoconservation, leading to Geomanagement, Geo-education and Geotourism. Geomanagement needs to be undertaken prior to the use of sites for Geo-education and Geotourism. In relation to Geomanagement, sites need to be investigated for safety issues, and for the protection of their geological features. Geodiversity, the eighth ‘G’, is outside the progression but plays an important part in underpinning biodiversity. There is also a need to address and manage geodiversity in a given region or specific site to help understand and manage biodiversity.  相似文献   

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