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1.
Review of the historical development of the step-drawdown pumping test and interpretations of well test data using the step-drawdown method indicates considerable differences in the importance attributed to head losses in the artificial environment (e.g., the gravel pack and screen) in the immediate vicinity of the wellbore and the losses resulting from non-laminar flow in the aquifer itself. These differences appear to be greatest when attempts have been made to apply the step-drawdown analysis to data from wells in fractured rock aquifers. The empirical flow-head loss relationship for a single, hydraulically-rough, open fracture have been incorporated into a mathematical expression for two-regime, radial, convergent flow. The resulting equation estimates the laminar and non-laminar head losses resulting from flow to a well over a range of flow rates. Combining these head loss components yields a non-linear relationship between production, Q, and drawdown, s, that is similar to those observed for actual step-drawdown tests in fractured rock aquifers. These test data are well approximated by: s = BQ + CQn where both B and C are assumed to be constants and n is typically in the range of 2.0 to 3.0. 相似文献
2.
《Proceedings of the Geologists' Association. Geologists' Association》2023,134(4):375-387
This paper introduces the Special Issue of the Proceedings of the Geologists' Association on ‘Valuing the Quaternary – Nature Conservation and Geoheritage’, arising from the International Union for Quaternary Research (INQUA) Congress in Dublin, in July 2019. It presents an overview of the values of Quaternary geoheritage, which merit recognition as an integral part of nature conservation, to protect priority sites and features for scientific research and education, and to deliver wider ecological, cultural and aesthetic benefits. The paper highlights the benefits of incorporating knowledge and understanding of Quaternary geoheritage for nature conservation and society. Palaeoenvironmental, palaeoecological and palaeobiological archives are a key source of ecological and environmental data that allow learning from the past to help address contemporary conservation challenges such as biodiversity loss, anthropogenic pressures and climate change. Quaternary science plays a vital part in supporting the wider nature conservation agenda, including strengthening the role of protected and conserved areas in the sustainable management of natural capital and ecosystem services, climate change adaptation, marine conservation, nature restoration and recovery, connecting people and nature and informing nature-based solutions to threats faced by society. However, challenges remain to achieve protection of key geoheritage sites and landscapes globally, and to integrate better understanding of geodiversity in nature conservation research, policy development and practice to help address the twin crises facing nature conservation – biodiversity loss and climate change. Quaternary studies provide temporal and spatial perspectives to inform forward-looking nature conservation that is dynamic rather than static in outlook. 相似文献
3.
As an important industrial city, Chongqing has experienced rapid economic growth in recent years, but at the same time the growth has been accompanied by serious pollution problems. Water quality monitoring shows that the waters of Chongqing are widely polluted. In this paper, the human capital approach is applied to assessing the economic losses and damages caused by water pollution in Chongqing. Based on previous studies and empirical investigations,water pollution-induced damage can be categorized into two general types: damage to ecosystems, including agriculture; and damage to non-ecosystems, including industry. The economic loss estimation of each type of the damage is conducted by taking into account a group of relevant parameters and methods. 相似文献
4.
Shifting Economic Impacts from Weather Extremes in the United States: A Result of Societal Changes,Not Global Warming 总被引：4，自引：2，他引：4
Loss values from extremes in the U.S. and elsewhere have been more qualitativethan quantitative, but recent pressures for better information have led to newassessments and better estimates of financial losses from extremes. These pressureshave included concerns over potential impacts of more extremes due to global warmingfostered by ever increasing costs to the insurance industry and government from weather extremes; plus a series of massive losses during the past 15 years (drought of 1988–1989,Hurricane Andrew in 1992, and Midwestern 1993 floods). These recent assessmentsattempted to adjust data for societal changes over time and thus derived new and betterestimates of losses for seven major extremes than existed previously. Three extremeshave annual average losses in excess of a billion dollars (1998 dollars) includinghurricanes ($4.2 billion), floods ($3.2 billion), and severe local storms ($1.6 billion).One extreme and its adjusted losses exhibit upward trends (floods), but all others showno increases with time or temporal decreases (hail, hurricanes, tornadoes, and severethunderstorms). Annual national losses during 1950–1997 from the three major extremes, plus four others (hail, tornadoes, winter storms, and wind storms), collectively reveal no upward or downward trend over time, with an average annual loss of $10.3 billion. The quality loss values do not indicate an increase as has been postulated for global warming. The good news is that better estimates of impacts now exist, but the bad news is that they are still estimates and do not include sizable unmeasured losses. If accurate data on the economic impacts from weather extremes are seen as important for scientific research and policy-making for global warming, the U.S. needs a continuing program to adequately measure losses from weather extremes. 相似文献
5.
《Geoforum》2015
This paper is part of a larger project, looking at electricity access in rural India. For the project, a nine months long ethnographic research was carried out in five villages in Bihar, an eastern state of India. It involved looking at various sources of light – grid electricity, solar lanterns, biomass micro-grids and kerosene oil. The paper tries to understand, and explain, the cultural notions that dictate peoples’ specific lighting practices and lighting practices that propagate particular cultural notions. The paper argues that, through the mediation of materiality, light cultures (cultivates and propagates) culture and culture cultures light. It does this by engaging with three key ideas. First, it argues that light has a critical role in establishing and reinforcing honour. Following this, it examines light’s role in hospitality. Lastly, it connects light to the religious beliefs among Hindus, and looks at how culture affects the materiality of light. The paper approaches what light does and what it means as emerging from a material-culture assemblage, which embodies the external and the internal, the political and the productive, the corporal and the conceptual, the material, moral, and the sensible. From this, light emerges with dual – material and non-material – properties, as it interacts with culture. 相似文献
6.
《Geoforum》2016
Because of the role that peripheral forest landscapes played in postwar nation-building, the Lao military has long played a significant, even if often hard-to-see, role in the administration of the country’s protected areas. This role is becoming increasingly apparent as transnational market-based forest governance efforts begin to threaten military administration of protected areas. As a consequence, the multi-dimensional nature of security – both defensive in the classic military sense, but also increasingly economic and complex – is coming to light through uses of what we describe as the security exception: the invocation of national security, in this case by military actors, to manage the reach and efficacy of emerging forest governance efforts. Projects to reduce climate-related emissions from deforestation and forest degradation (REDD+) have been especially prone to trigger the security exception due to their focus on forest measurement and change over time, and are examined here in two cases from protected areas in western and southern Laos. We suggest that even as conflicts over forest management may be interpreted through the lens of foreign domination and the loss of domestic sovereignty – indeed the security exception feeds on such interpretations – these conflicts are better understood as struggles within the Lao state and society over the how to manage and use forest resources in a context of economic uncertainty and persistent underdevelopment. In such a context, the role of conservation NGOs and Western donors as gatekeepers to ongoing transnational governance efforts is nonetheless highly significant. 相似文献
7.
《Geoforum》2015
Developing the notion of assemblage, this paper seeks to extend our understanding of drunkenness by exploring young people’s drinking practices in the night-time economy of Copenhagen, Denmark. The main argument is that drunkenness is an embodied and social practice which, in relation to a multiplicity of actors and forces particular to the place of drinking, increases and/or decreases the drunken body’s capacities to affect and be affected. Accordingly, Deleuze and Guattari’s concept of assemblage will be mobilized to cast light on how drunkenness emerges as the product of unpredictable yet patterned encounters between discourses, bodies (human and nonhuman), spaces, different drinks and consumption practices. In the analysis, which draws on qualitative empirical data from extensive fieldwork in a mainstream nightclub in Copenhagen, Denmark, it is shown how the drinking subjects’ capacity to initiate and sustain a number of – social, musical and sexual – relationships are altered by the consumption of alcohol in relation to the specific assemblage in which this consumption is enacted. 相似文献
8.
Tom Hargreaves 《Geoforum》2012,43(2):315-324
Drawing on Flyvbjerg’s (2001) call for the development of phronetic social science, this paper argues that much current research into pro-environmental behaviour (PEB) is misguided, and even potentially dangerous. After outlining Flyvbjerg’s argument, it reviews existing work on PEB and argues that, to date, it has predominantly sought after the Aristotelian intellectual virtues of either episteme or techne, and has neglected phronesis which Aristotle himself saw as most important. It then explores the ways in which aspects of a phronetic approach are being developed in cultural geography and environmental sociology, before offering a brief empirical case study of a PEB-change initiative to illustrate what a phronetic approach to research might look like. It concludes by calling for an improved and more reflexive dialogue between PEB researchers regarding the purpose and approach of their work, both in order to improve the relevance and impact of their research, and in order to help individuals and communities understand and confront the significant environmental challenges they currently face. 相似文献
9.
Here we describe the well-preserved skull of a juvenile specimen of Sapeornis, STM 16-18. Only the tail and hindlimb plumage of this specimen have been previously described. It preserves what we consider to be the complete dentition of Sapeornis with four premaxillary teeth, three maxillary teeth and two tiny dentary teeth on each side, the latter feature being previously unknown for this taxon. Based on a study of 71 specimens of Sapeornis preserving dentition, we infer the absence of dentary teeth in previously described specimens of Sapeornis is taphonomic, and consider the true dental formula of Sapeornis to be 4-3-2 (premaxillary teeth number – maxillary teeth number – dentary teeth number). Rostral to the dentary teeth, STM 16-18 preserves three shallow, empty aveoli. We hypothesize that this morphology captures an early stage in dental reduction and indicates that in at least some avian lineages, the loss of teeth was gradual. 相似文献
10.
Most earthquake loss studies use a probabilistic approach in which predicted damages in various categories of structure and facilities in the region in concern are estimated and added together to obtain a total loss for particular intensity ranges. Such an approach requires a detailed inventory database of the structures and facilities in the region, which is not always readily available in many regions of the world. We have used an alternative means of estimating earthquake losses based on several macroeconomic indices such as the gross domestic product and population. Using published earthquake loss data for 1980–1995, the relations between GDP and earthquake loss have been formulated empirically for several intensity ranges. The world's land surface was divided into unit cells 0.5° lat. × 0.5° long. in size. The GDP of each cell was apportioned based on its population and GDP, and the population of the region to which it belongs. The predicted seismic loss of the cell was then estimated from the seismic hazard probability function, its GDP, and the empirical relation between GDP and seismic loss. A global seismic loss map is then compiled both for the intensity at 10% probability of exceedance and the probable maximum intensity. Employing readily available socioeconomic data as the basis for the vulnerability analysis, the method enables us to obtain seismic loss estimates for regions without the need for a detailed inventory of exposed structures or collateral geological information. Since such statistics are frequently compiled by the world's leading political and financial institutions, the seismic loss estimates can also be upgraded easily for the fast developing areas of the world. 相似文献
11.
Losses due to natural disasters induce rural–urban migration throughout the world. It is also a major driver of population influx in Dhaka city, the capital of one of the most disaster-affected countries in the world, Bangladesh. While the relationship between natural disasters and migration is evident, the magnitude of household-level losses inducing rural–urban migration has not been widely discussed. This paper approaches this issue based on an empirical study. Using appropriate sampling procedure, a total of 407 households in Dhaka statistical metropolitan area were interviewed. This research finds out that 18.43% of rural–urban migrants in Dhaka city are disaster induced. A sharp drop in income immediately after the disaster is the predominant reason behind their migration. The river bank erosion-affected migrants encountered as high as 89% drop in income, whereas the flood-affected migrants experienced 70% drop. This article identifies five post-disaster components that ultimately determine migration. To conclude, the paper offers several approaches to minimize mass rural out-migration.
相似文献12.
The suitability of geologic frameworks for extrapolating hydraulic conductivity (K) to length scales commensurate with hydraulic data is difficult to assess. A novel method is presented for evaluating assumed relations between K and geologic interpretations for regional-scale groundwater modeling. The approach relies on simultaneous interpretation of multiple aquifer tests using alternative geologic frameworks of variable complexity, where each framework is incorporated as prior information that assumes homogeneous K within each model unit. This approach is tested at Pahute Mesa within the Nevada National Security Site (USA), where observed drawdowns from eight aquifer tests in complex, highly faulted volcanic rocks provide the necessary hydraulic constraints. The investigated volume encompasses 40 mi3 (167 km3) where drawdowns traversed major fault structures and were detected more than 2 mi (3.2 km) from pumping wells. Complexity of the five frameworks assessed ranges from an undifferentiated mass of rock with a single unit to 14 distinct geologic units. Results show that only four geologic units can be justified as hydraulically unique for this location. The approach qualitatively evaluates the consistency of hydraulic property estimates within extents of investigation and effects of geologic frameworks on extrapolation. Distributions of transmissivity are similar within the investigated extents irrespective of the geologic framework. In contrast, the extrapolation of hydraulic properties beyond the volume investigated with interfering aquifer tests is strongly affected by the complexity of a given framework. Testing at Pahute Mesa illustrates how this method can be employed to determine the appropriate level of geologic complexity for large-scale groundwater modeling. 相似文献
13.
An experimental study of the effect of Ca upon garnet-clinopyroxene Fe-Mg exchange equilibria 总被引：3，自引：1，他引：3
A series of basaltic compositions and compositions within the simple system CaO-MgO-FeO-Al2O3-SiO2 have been crystallized to garnetclinopyroxene bearing mineral assemblages in the range 24–30 kb pressure, 750°–1,300° C temperature. Microprobe analyses of coexisting garnet and clinopyroxene show that K D(Fe2+/MgG+/Fe2+/MgCpx) for the Fe-Mg exchange reaction between coexisting garnet and clinopyroxene is obviously dependent upon the Ca-content and apparently independent of the Mg/(Mg+Fe) content of the clinopyroxene and garnet. The Ca-effect is believed to be due to a combination of non-ideal Ca-Mg substitutions in the garnet and clinopyroxene. Our data and interpretation reconciles previous inconsistencies in the temperature dependence of K D ? values determined in experimental studies of simple systems, complex basalt, grospydite and garnet peridotite compositions. Previous differences between the effect of pressure upon K Das predicted from simple system theory (Banno, 1970), and that observed in experiments on multicomponent natural rock compositions (Råheim and Green, 1974a) can now be resolved. We have determined K Das a function of P, T, and X Gt Ca (grossular) and derived the empirical relation $$T\left( {^\circ {\text{K}}} \right) = \frac{{3104X_{{\text{Ca}}}^{{\text{Gt}}} + 3030 + 10.86P\left( {{\text{kb}}} \right)}}{{\ln K_{\text{D}} + 1.9034}}$$ . This empirical relationship has been applied to garnet-clinopyroxene bearing rocks from a wide range of geological environments. The geothermometer yields similar estimates for garnet-clinopyroxene equilibration for neighbouring rocks of different composition and different K Dvalues. In addition, temperature estimates using the above relationship are more consistent with independent temperature estimates based on other geothermometers than previous estimates which did not correct for the Ca-effect. An alternative approach to the above empirical geothermometer was attempted using regular solution models to derive Margules parameters for various solid solutions in garnets and clinopyroxenes. The derived Margules parameters are broadly consistent with those determined from binary solution studies, but caution must be exercised in interpreting them in terms of actual thermodynamic properties of the relevant crystalline solid solutions because of the assumptions which necessarily have to be made in this approach. 相似文献
14.
Estimation of soil losses by USLE model using GIS at Mashhad plain, Northeast of Iran 总被引：2，自引：0，他引：2
Ali Bagherzadeh 《Arabian Journal of Geosciences》2014,7(1):211-220
The Universal Soil Loss Equation (USLE) is an erosion estimation model to assess the soil losses that would generally result from splash, sheet, and rill erosion. At the present study, spatial distribution of different erosion prone areas were identified by USLE model to determine the average annual soil losses at Mashhad plain, northeast of Iran. Soil losses were estimated on a 100?×?100 m cell basis resolution by overlaying the five digital parameter layers (R, K, LS, C, P). To determine the critical soil loss regions at the plain, cell-based USLE parameters were multiplied by Arc-GIS ver.9.3. The estimated annual soil losses values were subsequently grouped into five classes ranging from 0 to 0.25 t/h/year around the trough line of the plain at Kashaf-rud River to 2–10 t/ha/year at the hills and pediment plains. Our results indicated a good correlation between land units of hills and pediment plains with the values of soil losses at the study area (R 2 ?=?0.72), also the statistical analysis exhibited a high correlation between land use/cover of dry farming and soil losses (R 2 ?=?0.78). 相似文献
15.
Daniel Solís Larry Perruso Julio del Corral Brent Stoffle David Letson 《Natural Hazards》2013,66(2):271-289
A stochastic production frontier was used to measure the initial (i.e., bi-weekly) economic effects of hurricanes on commercial grouper (Serranidae) production in the Exclusive Economic Zone of the United States Gulf of Mexico from 2005 to 2009. We estimated the economic effects of productivity losses associated with specific hurricanes on the commercial grouper fleet. We also calculated the economic effects due to productivity losses during an entire hurricane season at the regional level. The empirical model controls for input levels as well as other factors affecting production to isolate the initial economic effect caused by hurricanes from other non-weather-related factors. The empirical results revealed that hurricanes striking the Gulf of Mexico coastline from 2005 to 2009 had a negative effect on the production of the commercial grouper fleet. The results also demonstrated the relative importance of inputs and regulations on fish production. 相似文献
16.
Ecology is receiving increased attention as a research focus for geography and other academic disciplines. A consideration of basic concepts and the relationship of such ideas to the organizing frameworks of individual disciplines is needed to define the position of ecology as a substantive field or methodological approach. Geographers are concerned with the identification and explanation of the spatial patterning of earth phenomena. The ecosystem concept, with an emphasis on structure, networks of interaction, and function, is quite useful for conducting such geographical investigations. It acquires enhanced value within the subfields of geography by refining the approach through topical foci. Cultural ecology is one example; in this case a system is studied in terms of how its various cultural and biophysical components relate to a cultural characteristic (s) selected as the focus of investigation. Ecology is thus viewed as a methodological approach with significant applications for geographic research. 相似文献
17.
《Geoforum》2017
This paper uses pork as a lens on China’s rural transformations. Taking the industrialization of pig farming in the reform era as a trace on broader processes of social and environmental change, it advances three arguments. First, the massive increase in pork production and consumption since 1978 has been propelled by an industrial meat regime. A party-state led and agribusiness-operated regime, it articulates modernist notions of meat-as-progress with the relentless drive for capital accumulation. Second, using Marx’s concept of metabolic rift, the paper examines how processes of concentration in the industrial meat regime are at the same time processes of separation. This dialectical approach highlights the contradictions inherent in ongoing attempts to disembed capitalist production from biological and social relations. Finally, while official party-state discourse conceptualizes “the rural” as a production base for surplus value, and/or as a site for preserving environmental integrity, the paper’s analysis reveals a further unofficial recasting of the rural: in the process of agroindustrialization, the rural is also a sink for offloading capitalist crises. Between the rivers of manure that flow from industrial livestock operations and contaminate rural waterways; the loss of soil nutrients and food calories in the inefficient conversion of grains and oilseeds into industrial meat; the erosion of agricultural knowledge and practice that accompanies the dispossession of China’s farmers; and the shifting values of pigs, pork, and manure, this is a system that “wastes” the rural in service of capital. 相似文献
18.
Plate anchors, such as suction embedded plate anchors and vertically driven plate anchors, offer economically attractive anchoring solutions for deep/ultra-deep water offshore developments. The rotation/keying processes of plate anchors will cause embedment losses, which lead to decreases of the uplift resistances of the anchors in normally consolidated soil. In the present paper, the keying processes of vertically installed strip and square plate anchors are simulated using the 3-D large deformation finite element method. The effects of loading eccentricity and pullout angle on the embedment loss during keying are investigated. Both the development of the uplift resistance and the soil flow mechanisms are presented. The numerical results show that the loading eccentricity e/B has a much larger effect on the embedment loss than the pullout angle does. The anchor shape has a minimal effect on the loss in anchor embedment. The shape factors (square/strip) are 1.05–1.09 for loss of embedment and 1.10–1.19 for capacity. 相似文献
19.
《Journal of African Earth Sciences》2011,59(5):787-798
The word “mazuku” in Swahili means “evil wind”. It corresponds to lowland (depressions) where carbon dioxide is released and, being heavier than air, accumulates at high – often lethal – concentrations (10 vol.% of CO2 in atmosphere can be considered as the deadly threshold, even for a short time exposure). Mazuku are abundant in Goma and surrounding areas and particularly in the area south of the large volcanic edifices of Nyiragongo and Nyamulagira volcanoes located in the most eastern part of DR Congo, W branch of the East African Rift System (EARS). Our extensive field surveys have indicated that mazuku are concentrated within to and around the densely populated city of Goma close to the N shores of Lake Kivu, mainly near fault or fissure networks. At a more local scale, depressions allowing CO2-rich gas accumulation are created by lava flow superposition, lava tunnels or cavity collapses, or directly associated with open fractures. People are killed by mazuku every year. Given political and social unrest coupled with the current important demographic and urban growths around Goma, the risks associated to mazuku are increasing accordingly. Mazuku are currently the most important natural risk in terms of human loss for the area and there is an urgent need for further research, more systematic mapping and monitoring of mazuku and for appropriate risk management to be implemented. This paper summarizes the current scientific knowledge on mazuku as well as new advances and a preliminary risk assessment performed recently in the frame of the GORISK project. 相似文献
20.
S. P. Villacorta K. G. Evans K. Nakatani I. Villanueva 《Australian Journal of Earth Sciences》2020,67(3):425-436
AbstractLarge debris flows in steep-sloped ravines debouching to the Rimac River, in metropolitan Lima (Peruvian capital), have resulted in considerable loss of life and property adversely impacting communities in the region. Temporal, spatial and volumetric features of debris flows are difficult to predict, and it is of utmost importance that achievable management solutions are found to reduce the impact of these catastrophic events. The emotional and economic toll of these debris flows on this increasingly densely populated capital city in South America is devastating where communities must live in such inadequate and dangerous conditions. To address this problem, the application of advanced Japanese technology, Sustainable Actions Basin Orientation (SABO), has been investigated using a geomorphological modelling to develop an implementation plan. Rayos de Sol stream basin in Chosica, was selected as a pilot to develop the proposal, as it is considered high risk due to the presence of ancient debris flows and recent flows in 2012, 2015 and 2017. The recurrence of debris flows in this location has resulted in numerous deaths and catastrophic property losses. This study combines geologic and geomorphic mapping and hydraulic and landform evolution numerical modelling. The implementation of a SABO Master Plan based on the multidisciplinary assessment hazard scenarios, will allow the implementation of feasible mitigation actions. The SABO technology has been applied successfully in Japan and other countries in areas with steep short slopes, similar to the conditions surrounding the Peruvian capital. Results from this study will be presented to the Peruvian Government as part of an action plan to manage debris-flow impact.
- KEY POINTS
High-risk mass slope failure is linked to poor urban planning in urban developing regions of Lima the capital of Peru.
A multidisciplinary study including geotechnical and hydrological analysis, engineering design, and socio-economic research is required to implement a SABO Master Plan, and this basin is pilot study basin.
At the present time, a maintenance programme for existing hydraulic structures should be implemented, and a flood risk management plan developed may propose the relocation of some communities and infrastructure.