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1.
Of all the materials required for construction of a new town, the only one that must be obtained locally is aggregate for concrete. Very large tonnages of sand and gravel, or crushed stone, will be needed. Their production must be planned for from the beginning, to avoid the conflicts in land use that have long plagued older communities that undergo expansion. Production of sand, gravel, and stone is now disallowed by zoning in most major urban corridors in the U.S.A., making it necessary to bring these materials from a distance, at higher costs than formerly. Yet some success has been achieved in fitting the aggregates industry into the urban picture. Two examples are cited, involving production of stone in New Jersey and gravel in southern California. Where planning is done from the start, areas of occurrence of sand, gravel, or good-quality stone must be set aside for extractive industry. It is the geologiest's responsibility to provide information on locality of occurrence, tonnage present, thickness of overburden, best way to exploit the deposit with minimum environmental effect, and feasible use of the area after it has been worked out. The possibility of obtaining stone from below ground should also be evaluated. Only by such advance planning, with geological input, can conflicts in land use and excessive cost of construction aggregate be avoided.  相似文献   

2.
During the last several decades, harmful algal bloom (HAB) events have been observed in more locations than ever before throughout the United States. Scientists have identified a larger number of algal species involved in HABs, more toxins have been uncovered, and more fisheries resources have been affected. Whether this apparent increase in HAB events is a real phenomenon or is the result of increased sampling and monitoring is a topic of intense discussions within the scientific community. We also have an inchoate understanding of the reasons for the apparent increase, particularly concerning the role of anthropogenic nutrient loadings as a causal factor. Whatever the reasons, virtually all coastal regions of the U.S. are now regarded as potentially subject to a wide variety and increased frequency of HABs. It is important to begin to understand the scale of the economic costs to society of such natural hazards. It is a common, but not yet widespread, practice for resource managers and scientists in many localities to develop rough estimates of the economic effects of HAB events in terms of lost sales in the relevant product or factor markets, expenditures for medical treatments, environmental monitoring and management budgets, or other types of costs. These estimates may be invoked in policy debates, often without concern about how they were developed. Although such estimates are not necessarily good measures of the true costs of HABs to society, they may help to measure the scale of losses and be suggestive of their distribution across political jurisdictions or industry sectors. With adequate interpretation, our thinking about appropriate policy responses may be guided by these estimates. Here we compile disparate estimates of the economic effects of HABs for events in the U.S. where such effects were measured during 1987–1992. We consider effects of four basic types: public health, commercial fisheries, recreation and tourism, and monitoring and management. We discuss many of the issues surrounding the nature of these estimates, their relevance as measures of the social costs of natural hazards, and their potential for comparability and aggregation into a national estimate.  相似文献   

3.
Modern analytical techniques, such as Inductively Coupled Plasma Mass Spectrometry, can routinely determine the abundances of a wide range of trace elements in ultramafic to felsic igneous rocks. Exploration strategies for massive sulfide deposits can be significantly refined with these techniques because the same tectonic controls affect both the geochemical signatures of volcanic rocks and their potential to host synvolcanic ore types. The prospectivity assessment approach is not greatly affected by uncertainties regarding Archaean plate tectonics once sufficient data exist to empirically characterise strongly and weakly prospective units. Although high‐precision techniques are more expensive than the methods routinely employed by industry, the results of even a small number of analyses can dramatically reduce the costs and improve the efficiency of a massive sulfide exploration program. These techniques have previously been applied in relatively unweathered terranes of the Superior Province and Trans‐Hudson Orogen. In the future, they are also likely to be applied in the Yilgarn Craton and similar regions through analysis of saprock samples in addition to less‐abundant outcrop exposures.  相似文献   

4.
在水资源趋紧和水需求增长的背景下,水成为经济发展的约束资源,亟待“以水定城、以水定地、以水定人、以水定产”,把水资源作为最大的刚性约束,推动用水方式由粗放向节约集约转变。为将“以水四定”与农业、生活、工业、城镇发展相对应,本文将“地、人、产、城”分别定义为耕地面积、人口规模、工业增加值总量、城镇建设用地面积。在此基础上,初步探索了水资源承载评价方法,引入了“综合定额”的概念,力求揭示耕地与主要农作物、工业与耗水行业的内在联系与计算规则。通过全国31个省区市的评价结果显示,浪费情景处于超载,节约情景有较大盈余,倒逼节水行动。在水资源承载最大规模下,全国仍有超载区,耕地超载呈中部“塌陷”,人口超载呈环状“倒塌”,工业超载呈区域性“沦陷”,城镇用地超载呈沿海少点“亏空”,该区域需要从水资源总量、结构、效率等方面提升承载规模。  相似文献   

5.
张永康 《江苏地质》1996,20(3):129-136
江苏优质矿产主要有五大类:即粘土类矿产,建材类矿产,化工原料矿产,冶金辅助原料矿产,特种用途矿产。江苏矿产资源的开发应注重开源,开优,开新和开外相结合的原则。适当加大地质工作投入,实施好全省矿产资源勘查工程,力争实现矿产资源的重大突破。大力开发优势矿产资源,提高全省非金属矿开发利用水平,形成一批非金属矿产原材料基地。依靠科技进步,开发新产品,新矿种,振兴矿业经济。  相似文献   

6.
Keith Chapman 《Geoforum》1983,14(1):37-44
Most analyses of agglomeration in manufacturing evaluate the merits of clustered and dispersed spatial arrangements of plants in terms of their effects upon the profitability of individual enterprises. However, the problem of defining optimal levels of agglomeration becomes very much more acute if the costs and benefits are considered with reference to society as a whole. Examples of air and water pollution from petrochemical plants in Texas and Louisiana are used to illustrate these difficulties. It is argued that the technology and economics of pollution control have tended to reinforce the cost advantages to industry of agglomeration in large complexes despite the fact that major concentrations of polluting industries may be regarded, from a broader environmental perspective, as intrinsically undesirable.  相似文献   

7.
In the beginning of the 20th century, many streams in western Iowa were channelized to reduce flooding and to open swamp land to cultivation. Channel straightening accomplished its goal. However, it resulted in greater streamflow velocities, causing stream channels to degrade. This degradation has resulted in significant loss of land and damage to transportation and communications infrastructure in western Iowa and in several states in the United States. Baumel et al. (1994; Impact of Degrading Western Iowa Streams on Private and Public Infrastructure Costs. Final Report Iowa DOT HR-352, Stream Stabilization in Western Iowa) estimated the historical cost of this degradation on land loss and damage to transportation and communications infrastructure in western Iowa. The purpose of this paper is to extend the Baumel et al. analysis to estimate future degradation costs on 141 streams in western Iowa. It also presents two types of degradation cost estimates. One is a time neutral cost that does not consider the dates on which the degradation costs are incurred. The second is a time value cost which considers the dates on which the costs are incurred and then discounts these costs back to 1992 dollars. The time value costs are the more accurate estimates of the cost of future degradation in 1992 dollars and should be used to evaluate stream stabilization project proposals.  相似文献   

8.
We studied the methods of wastewater treatment of hydrophilic cotton producing industries. Several major cotton producing countries, such as India, have provided very stringent environmental standards for these industries, and it is expected that these standards are becoming more stringent day by day. This is necessary for monitoring and control facilities, in order to minimize problems and difficulties associated with treated wastewater disposal. Unit processes of these industries are: pretreatment, dyeing, printing and other complementary processes. In this industry, aside from considerable amounts of energy and water consumption, considerable quantity of wastewater is also produced. This article discusses all types of waste producing hydrophilic cotton processes; we have also advanced wastewater treatment methods, such as electrical oxidation, membrane processes, biological and photochemical treatments. Results showed that traditional methods of wastewater treatment are compound methods including physical–chemical and biological methods, and requires substantial investment and operational costs. Compared to traditional methods, membrane systems are very effective methods and are a good substitute. Investigation showed that hybrid treatment methods that include absorption and absorption by nano-filtration can play an effective role in improving treated wastewater quality. Moreover, advanced treatments such as ion exchange systems can improve wastewater quality to the extent that it can be recycled to the production processes for second usage.  相似文献   

9.
Climate Change and Extreme Weather: A Basis for Action   总被引:2,自引:0,他引:2  
McBean  Gordon 《Natural Hazards》2004,31(1):177-190
The economic and social costs of extreme weather-related events have been increasing around the globe. There is some debate over how much of this past increase has been due to social factors and how much due to changes in frequency or characteristics of extreme events. The Intergovernmental Panel on Climate Change (2001a) has affirmed that humans are having a role in changing the climate and will have a larger role in the future. Although the changes in extreme events are by their nature both difficult to detect and difficult to model, the consensus is that there will be changes in the future. Through a risk-based decision-making analysis, it is concluded that society should make the additional investments to reduce vulnerability to this increased risk.  相似文献   

10.
The recent global scenario in the mineral sector may be characterized by rising competitiveness, increasing production costs and a slump in market price. This has pushed the mineral sector in general and that in the developing countries in particular to a situation where the industry has a limited capacity to sustain unproductive costs. This, more often than not, results in a situation where the industry fails to ensure environmental safeguards during and after mineral extraction. The situation is conspicuous in the Indian coal mining industry where more than 73% production comes from surface operations. India has an ambitious power augmentation projection for the coming 10 years. A phenomenal increase in coal production is proposed from the power grade coalfields in India. One of the most likely fall-outs of land degradation due to mining in these areas would be significant reduction of agricultural and other important land-uses. Currently, backfilling costs are perceived as prohibitive and abandonment of land is the easy way out. This study attempts to provide mine planners with a mathematical model that distributes generated overburden at defined disposal options while ensuring maximization of backfilled land area at minimum direct and economic costs. Optimization has been accomplished by linear programming (LP) for optimum distribution of each year’s generated overburden. Previous year’s disposal quantity outputs are processed as one set of the inputs to the LP model for generation of current year’s disposal output. From various geo-mining inputs, site constants of the LP constraints are calculated. Arrived value of economic vectors, which guide the programming statement, decides the optimal overburden distribution in defined options. The case example (with model test run) indicates that overburden distribution is significantly sensitive to coal seam gradient. The model has universal applicability to cyclic system (shovel–dumper combination) of opencast mining of stratified deposits.  相似文献   

11.
The use of gas‐storage caverns in salt formations is a growing industry that continues to gain momentum because it allows gas to be injected and withdrawn at high rates compared with other underground gas‐storage systems such as porous rock systems. In order to predict cavern production performances, cavern thermodynamics behaviour must be studied by higher accuracy approaches. This behaviour is extremely related to the temperature distribution in the surrounding formations. During the leaching process, the thermal equilibrium of the rock salt surrounding the cavern is extensively disrupted. The purpose of this paper is to study the heat transfer problem during the leaching process and to develop a thermal model that can be easily used in field applications. The results of this work will be the input data for the prediction of the gas temperature and pressure during cavern gas‐storage operation phase. Moreover, the developed model can find its use in the design of salt caverns since it can be coupled with geometrical modelling of salt dissolution codes. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

12.
Mike Morris  Nikki Dunne 《Geoforum》2004,35(2):251-266
In this new globalised era there is an increasing demand in the developed world for environmental certification (Forestry Stewardship Council) of furniture and timber products. The imposition of this requirement has major implications for producers in developing countries. This paper examines this issue from a value chain perspective, exploring how certification requirements are driven through the links of the global furniture value chain. It does so by focusing on the dynamic underlying the spread of FSC certification through the furniture and timber industry in South Africa, and investigates the role of the various organisational ‘drivers’ of the system. In doing so it explores how developing country firms relate to these opportunities and pressures, drawing out the logistical implications, the costs and benefits, as well as the future for FSC certification. It concludes with a discussion of the role of buyers, agents, certification agencies and manufacturers in driving FSC certification through the wood products value chain in South Africa.  相似文献   

13.
A.J. van Loon 《Earth》2008,86(1-4):247-254
Several developments cause that field practice of students becomes minimized in most countries. The most important reasons are, direct or indirect, financial short-sightedness, an ever increasing population pressure, vandalism, and counterproductive legislature. The diminishing field experience forms a threat for the capability of future generations of earth scientists to optimize exploration of all kinds of natural resources, thus also threatening society. As it is unlikely that the present-day tendency of diminishing availability of excursion points and areas for field work will come to an end, measures should be taken timely to preserve sites that are of educational (or scientific) value. National measures and international cooperation aimed at preserving our geological heritage, like realized already in, for instance, the US by the National Park Service and in Europe by ProGeo, form a step in the good direction. Dependency on such preserves will, however, change the education of earth scientists fundamentally. However unfortunate such a development may be, it is better than a future where geological education becomes impossible because essential parts of our geological heritage have been lost forever.  相似文献   

14.
Geosites are important and/or unique geological or geographical features of significance. Typically they comprise geological, palaeontological, as well as archaeological sites. Geosites should be regarded as deserving to be preserved and protected, either from the elements or from destructive human activities, both for the community and future generations. A good knowledge of geological heritage, and a healthy respect for it, is an important factor in the holistic approach for sustainable development. Very often, these sites bear a multi‐faceted ‘story’, which may date back from very recent times to billions of years ago. As such, geosites are of great educational and scientific value. In Africa, such sites have not been receiving the attention they deserve. Only a few countries on the continent acknowledge their importance. Within the framework of a Sustainable Management of Mineral Resources Project (SMMRP), geological mapping, geochemical surveys and mineral resources assessment in selected areas of Uganda have been completed under the umbrella of the Geological Survey of Finland (GTK), and the Department of Geological Survey and Mines (DGSM, Uganda). Apart from recording ‘hard‐tough’ geology, 62 geosites were documented in 2010 and 2011. For the first time, such sites have been incorporated in the new geological maps of the country (at a scale of 1: 250 000). It is possible that this is the first time that such places have been shown on geological maps of Africa. Currently, the extreme north‐east of the country is being geologically mapped by DGSM, with the eventuality of more possible geosites being discovered.  相似文献   

15.
Keeping temperature rise well below 2 °C is Paris Climate Agreement’s main commitment and corporate-level participation will be crucial to achieve national mitigation targets. Hence, companies should adopt measures that allow them to adapt to upcoming scenarios where low-carbon production is expected to become mandatory and a great competitive advantage. However, mitigation strategies cannot be evaluated without consideration of subjective environmental criteria. Consequently, lack of decision support methodologies for climate change evaluation in industries is a barrier for innovation. Aiming at consideration of non-monetary aspects, we develop a support method that incorporates costs, benefits, opportunities and risks related to climate change in manufacturing industries. First, we compared the most relevant multi-criteria decision analysis methodologies and identified an Analytic Hierarchy Process (AHP) as the most suitable for ranking corporate climate change strategies. Then, we collected global analysis criteria from the most important socially responsible investment indices, and climate change scientific studies. To adapt these criteria to the AHP method, each criterion was sorted into benefits, opportunities, costs or risks hierarchies. Proposed method was efficient for assessing long-term subjective criteria and ranking alternatives for GHG emission management in two large manufacturing companies. A sensitivity analysis of the outcome revealed its consistency and flexibility for ranking alternatives and weighting criteria. Finally, the method is not limited to a particular type of industry and it can be adapted to other areas, such as service companies, sanitation or public sector.  相似文献   

16.
The assumption of lognormal (parent) field size distributions has for a long time been applied to resource appraisal and evaluation of exploration strategy by the petroleum industry. However, frequency distributions estimated with observed data and used to justify this hypotheses are conditional. Examination of various observed field size distributions across basins and over time shows that such distributions should be regarded as the end result of an economic filtering process. Commercial discoveries depend on oil and gas prices and field development costs. Some new fields are eliminated due to location, depths, or water depths. This filtering process is called economic truncation. Economic truncation may occur when predictions of a discovery process are passed through an economic appraisal model. We demonstrate that (1) economic resource appraisals, (2) forecasts of levels of petroleum industry activity, and (3) expected benefits of developing and implementing cost reducing technology are sensitive to assumptions made about the nature of that portion of (parent) field size distribution subject to economic truncation.  相似文献   

17.
Phil McManus   《Geoforum》2008,39(3):1296-1307
The Upper Hunter region of New South Wales (NSW) around Scone is reputed to be the second most significant thoroughbred breeding region in the world after the Bluegrass region of Kentucky. This article identifies the importance and cultural constructions of grass, and hence water, in the thoroughbred breeding industry in this region. Thoroughbred stud managers attempt to produce environments attractive to potential horse purchasers and owners with mares to be mated. These environments are constructed from perceptions of how a thoroughbred stud should appear, and from the physical conditions of specific locations. One perception is that the grass should be green. There are differing opinions in the thoroughbred breeding industry about the nutritional value of irrigated grasses, the role of these grasses in horse development and the associated access to, cost of and efficacy of water used for this purpose. The paper concludes that effective water management in this industry is only possible if various cultures of nature are understood, where necessary challenged, and subsequently included in policy and planning.  相似文献   

18.
 Sediments from stormdrain catchments in Wellington city and sediment traps from Wellington Harbor were sampled for trace metal content. Samples were analyzed for acid leached metal content by extraction with 0.11 mol acetic acid l–1 and using ICP-MS. Cu and Zn levels in harbor sediment traps increased towards the periphery of the harbor, while Pb levels adjacent to a road almost doubled. In general, areas of light industry in the Inner City stormdrain catchments exhibited higher acid leached metal concentrations. However, large-scale renovation work probably contributed to point sources of high metal levels. The proximity of stormdrain outlets to recreational activities, such as wharf fishing and shellfish gathering, should be of prime concern to local authorities. Some positive correlations are found between acid leached and total metal levels. These may prove useful for assessing the biological impact of significant increases in total metal concentrations in the vicinity of Wellington Harbor. Significant savings in the time and costs of analyses may be achieved. Received: 27 February 1998 · Accepted: 27 April 1998  相似文献   

19.
<正>The rapid identification based on InSAR technology was proved to be effective in our emergency investigation of surface ruptures and geohazards induced by the Yushu earthquake.The earthquake-generating fault of the Yushu earthquake is the Yushu section of the Garze-Yushu faults zone.It strikes NWW-NW,23 km long near the Yushu County seat,dominated by left-lateral strike slip,and appearing as a surface rupture zone.The macroscopic epicenter is positioned at Guo-yang-yan -song-duo of Gyegu Town(33°03'11"N,96°51'26"E),where the co-seismic horizontal offset measured is 1.75 m.Geohazards induced by the Yushu earthquake are mainly rockfalls,landslides,debris flows, and unstable slopes.They are controlled by the earthquake-generating fault and are mostly distributed along it.There are several geohazard chains having been established,such as earthquake,canal damage,soil liquefying,landslide-debris flow,earthquake,soil liquefying,roadbed deformation,etc.In order to prevent seismic hazards,generally,where there is a visible surface rupture induced by the Yushu earthquake,reconstruction should be at least beyond 20 m,on each side,from it.Sufficient attention should also be given to potential geohazards or geohazard chains induced by the earthquake.  相似文献   

20.
Sea‐level surges caused by sirocco wind are frequent in the northern Adriatic. Added to the local spring‐tide amplitude of about 40 cm, they should not be disregarded when estimating the elevation of maritime archaeological structures in relation to their function at the time of their construction. Based on the statistical analysis of the frequency and distribution of hourly sea‐level surges at Trieste, Rovinj, and Venice, realistic estimates of functional heights for sea‐level reconstructions to be applied to archaeological remains of coastal structures, e.g., fish tanks, appear to be approximately 120–130 cm near Trieste and around 95–105 cm in the Rovinj area. These exceed the value of 60 cm recently proposed by a group of archaeologists. Such underestimation tends to lower by about half a meter (in relation to certain previous estimates) sea‐level position in Roman times along the coast of Istria. The sea level during this period should be derived from more accurate sea‐level indicators such as marine biological remains preserved on archaeological structures.  相似文献   

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