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1.
Haripriya Rangan 《对极》1995,27(4):343-362
Prominent environmental scholars and activists in India have posited that environmental crises in the Indian Himalayas result primarily from adopting forestry practices that override local communities and argue that the region can be sustained only when the state allows local communities to practice indigenous forest management. This paper challenges those critiques: focusing on the Garhwal Himalayas, it shows that forestry practices involve contestation and negotiation between the state and local communities and argues that environmental scholars fail to recognize how particular classes have shaped forest use and management practices and played a central role in determining environmental sustainability for local communities.  相似文献   

2.
Buddhist monasteries in Sikkim Himalayas constitute important religious and architectural heritage. These random rubble (RR) stone masonry structures located in high seismically active regions of the Himalayas have suffered varied degrees of damages in the past earthquakes. The study presents seismic vulnerability assessment of four archetypal monastic temples using finite element (FE) analyses. Linear and nonlinear analyses of these structures were conducted in Abaqus FE environment. These analyses identified the damage prone areas of the structures and provided load-deformation behavior under lateral loads. Fragility analyses indicate a high probability of collapse for the specified design level earthquake of the region. The study shows that performance of the structure can be enhanced by improving the strength and stiffness of the stone masonry walls.  相似文献   

3.
The Himalayas are among the world's youngest mountain ranges. In addition to the geologic processes of mountain building and erosion, they are also highly vulnerable to human influenced change, occurring at local, national, regional, and international scales. A photo-elicitation methodology is employed to show how residents perceive those changes from historical perspectives, as well as their current conditions and impacts on their daily lives. Nepal's Khumbu region has undergone major social and environmental transformations since the 1960s when international trekking first began to influence the area's economy. The current perceptions of Khumbu residents of these changes are assessed through photo-elicitation interviews. Their responses are placed in the historical context of: (1) institutional and political changes, most of which have been driven by national government policies; (2) social and economic changes, for which the tourism economy has been central; and (3) environmental changes, reflecting the impacts of resource management and climate change. The mostly positive perceptions of Khumbu residents toward how their region has changed reflects general improvements in the physical and cultural landscapes of the Khumbu over time, as well as its continuing geographic isolation, which has helped to slow the rate of globalization, while also keeping the region a dynamic and popular tourist destination.  相似文献   

4.
We describe a preliminary survey of a relatively unknown part of the eastern Himalayas: northwestern Sichuan. This survey revealed that three phases of occupation are represented across the landscape. Large settlements with dense remains characterize the landscape during the Neolithic (3400–2000 cal b.c.). Following a hiatus in occupation, stone-cist graves characterize the region during the Bronze Age (1450–800 cal b.c.). The lack of settlement remains from this period indicates that mobile pastoralism increased in importance. Finally, between a.d. 500 and 1500, dense scatters of ceramics over a wide altitudinal range correspond to a fragmentation in Tibetan history, when local warlords established themselves in the region. While some changes in occupation and subsistence practices are linked to climate change, others relate to changes in political power. We argue that further survey work is needed to expand our understanding of past land use and the development of pastoralist practices.  相似文献   

5.
Previously developed regression formulae for estimating body mass in dogs and wolves based on cranial and mandibular dimensions are evaluated using modern canid specimens of known weight at death. Some of these equations proved reliable, but others have large standard errors of estimate and likely produce unreliable mass estimates. New sets of equations for estimating body mass in dogs and wolves are produced using our datasets, including a set of equations developed from combining the dog and wolf biometric data into a single population. The resulting regression equations allow body mass to be estimated from a series of cranial and mandibular dimensions with relatively low errors. Further, our datasets include larger numbers of specimens of larger ranges of body mass than in these previous studies. When the equations are applied to a suite of dogs and one wolf from Eastern Siberia, several patterns emerge. First, hunter–gatherers' dogs in this region vary widely in terms of body size, even within a limited geographic area and time period. Some were quite large, similar in size to modern Siberian huskies. Second, pastoralists' dogs are less variable in terms of body mass, but this may reflect the nature of our samples. In particular, pastoralists' dogs nearly all were sacrificed juvenile dogs, some of which appear to have been eaten. These dogs seem to have been approached adult body size when they were selected for sacrifice. Finally, our findings help to highlight the need for further refinement in methods used to study ancient canid remains. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   

6.
This paper examines the feasibility of deriving a climatology of the diurnal variations of the wind in the 85–120 km region from the tidal components of temperature, density, and composition contained in the new COSPAR International Reference Atmosphere, CIRA-1986, Part I: Thermosphere Models [(1988), Adv. Space Res.8, 9]. To derive the wind field, we used the zonal and meridional momentum equations which have been modified from the characteristic scales of the tidal components observed in the 85–120 km region. The CIRA temperature and density model was used to derive the eastward (westerly) and northward (southerly) pressure gradient forces which serve as the forcing functions in the coupled momentum equations. Ground-based wind data from the Mesosphere-Lower Thermosphere (MLT) radar network is used as an independent data set to check the accuracy of the derived tidal wind model. At midlatitudes, the model reproduces some of the general features observed in the radar tidal data, such as the dominant semidiurnal tide with increasing amplitude with height and clockwise (counterclockwise) rotation of the velocity vector observed in the northern (southern) hemisphere. The model overestimates the semidiurnal amplitudes observed by radar by 50–75% during most seasons with the best agreement found during the equinoctial months. The model exhibits little phase variation with height or season, whereas the radar data exhibit a downward phase progression during most seasons (other than summer) characteristic of upward propagating tidal waves, and large seasonal phase variations associated with seasonal changes in vertical wavelengths. The diurnal tidal amplitudes, which are generally 5–20 m s−1 at mid-latitude radar stations and are dominant over the semidiurnal amplitudes at lower latitudes, are less than 5 m s−1 at all latitudes in the model.  相似文献   

7.
Sikkim, a small Eastern Himalayan state in India has twenty-seven hydropower projects proposed under the Indian Power Ministry's hydropower initiative that envisions the Himalayan region as the country's "future powerhouse" (Dharamadhikary 2008; Kohli, 2011). In 2011, a 6.9 magnitude earthquake rocked Sikkim, the epicenter of which was located eerily close to two under construction dams and the Dzongu reserve, revered as sacred by Sikkim's Indigenous minority Lepchas. Drawing on interviews with Lepcha residents of Dzongu, and state geologists and disaster management officials, I center my analysis on their encounters with disasters and hydropower infrastructure. Building on decolonial theorizations and scholarship on Himalayan borderlands, I argue that disastrous hydropower forms on historical terrains shaped not only by geophysical conditions but also generations of uneven regional development, and the racialized colonial and postcolonial governance of the Eastern Himalayan frontier. In placing ‘disastrous’ as a prefix to hydropower, I follow my interlocutors who implicate state and private developers in producing disaster conditions in Sikkim even as they evade culpability by discursively shifting blame onto the region's “inhospitable terrain” (GoI 2008: 27). I demonstrate that despite key differences in their relation to state power both Dzongu Lepchas and Sikkimese technocrats, forward a materialist, place-based understanding of precarity, differential vulnerability, and uneven regional development. Centering Indigenous and regionalist critiques, I argue that the recent entry of hydropower development in the Eastern Himalayas, conceptualized by colonial authorities as India's “Mongolian Fringe” (Baruah, 2013), requires a closer attention to the entanglements of frontier-making and racialization in India. More broadly, I demonstrate how disastrous hydropower development in a racialized frontier region offers a productive entry into decolonial theorizing in the Indian context.  相似文献   

8.
This article presents new ground-motion prediction equations for three distinct seismic regions of Iran via updating the previous global model using observed data for each region by means of Bayesian updating. The Bayesian theory has the advantage that it results in more accurate results even in situations when little data is available. This leads the way for updating global models to obtain new local models for seismotectonic regions with little available data like Iran. The proposed updated model was compared against currently available models for Iran and the results reveal the overall stability and quality performance of the proposed model.  相似文献   

9.
The development of complex societies, irrigation agriculture and sociopolitical transitions are of interest to researchers working in the Nasca region on the south coast of Peru. Occupied for thousands of years, many questions regarding the circumstances of these changes in the area are being investigated. Oxygen isotope analysis provides a method for exploring residential mobility of past peoples during these transitions. This study presents new δ18O data from water sources that would have been used by the ancient inhabitants, providing important information regarding the oxygen isotope variability in the region and the necessary baseline data for migration studies in this region. Our results suggest that the isotopic composition of water sources in the Nasca region is not highly variable. In addition, archaeological human tooth enamel samples from the sites of La Tiza and Pajonal Alto are analysed. The δ18Oc results of the human enamel samples confirm the local nature of the burial population, as suggested by previous strontium isotope analysis (87Sr/86Sr). Copyright © 2010 John Wiley & Sons, Ltd. This article was published online on 13 January 2010. An error was subsequently identified. This notice is included in the online and print versions to indicate that both have been corrected 15 January 2010.  相似文献   

10.
As part of the DYANA Programme, six rocket launchings (ship-borne) were conducted on three days in the equatorial region (Indian Ocean/Arabian Sea region). Using the temperature and wind data from these launchings, the diurnal and semi-diurnal tidal components in wind and temperature in the middle atmosphere are obtained and are compared with theoretical predictions. It is found that significant departures occur between the observed and theoretical values. The results are discussed in the light of current theoretical understanding of the tides.  相似文献   

11.
Mt. Qomolangma is the loftiest mountain at the top of Himalayas;the mountain peak is shaped like a pyramid and penetrates directly into the sky offering a spectacular view.  相似文献   

12.
In this ethnography of India’s border roads, I follow the circular/seasonal journeys of migrant road labourers from Jharkhand to the upper reaches of the Himalayas and back. I pay particular attention to the notions of masculinity and nation-building as they reveal themselves in their travel narratives. These migrants travel every May to work as road construction labour for the Border Roads Organisation (BRO) of India working in the Himalayan frontiers. While the BRO advertises its roles through various road signs claiming to be ‘creating, connecting and caring’ (for) the nation – it is the ambivalent construction of the labourers gendered national subjectivities emerging in the narratives of and about the migrant labour that is of particular interest to this article. One of the central contributions of this article is to show how hierarchical domains of the nation and the hierarchical structures within masculinity intersect and rely upon each other to build gendered national subjects. This research is based on over five years of a very mobile ethnography.  相似文献   

13.
Finger millet, Eleusine coracana (Linn.) Gaertn. is usually considered to have been domesticated in tropical Africa. Nonetheless, it diffused across much of the Old World in prehistory, reaching Taiwan, the Himalayas, and Sumatra. The archaeobotanical record remains extremely patchy and the routes and dates of its arrival in many locations remain unknown. The paper makes use of comparative linguistics to begin the resolution of some of these issues. It reviews the archaeobotanical data which exists and then compiles tables of African and Asian names for finger millet. The paper identifies locally common linguistic roots, but there are no very widespread terms, suggesting there may a constant reborrowing of names with its near relative, goosegrass, Eleusine indica. A synthesis of the diffusion of finger millet is given at the end of the paper.  相似文献   

14.
Cross-sectional growth data were obtained from the skeletal remains of non-adults from the Raunds Anglo-Saxon site. Standard measurements of the diaphyseal lengths of the long bones of the upper and lower limbs and the maximum breadth of the ilium were recorded in order to construct skeletal growth profiles (SGP). In addition regression equations were used to estimate diaphyseal length from proximal and distal shaft widths, and epiphyseal breadth data for fragmentary remains. The skeletal measurements were then plotted against age estimates determined by the dental formation standards of Moorrees, Fanning and Hunt, and Anderson, Thompson and Popovich. The growth data were compared with sixth to seventh century German, ninth century Slavic and modern Caucasian data. With the exception of the ancient Slavic material, the Anglo-Saxon remains demonstrated the smallest rates of growth. Diaphyseal ageing curves derived from the Anglo-Saxon sample were tested for applicability on the non-adult cohorts of the Berinsfield and Exeter Anglo-Saxon/Early Medieval samples. Differences were observed between diaphyseal age as determined from the skeletal growth profiles for Raunds and calcification age assessed for individuals within the test samples. It is proposed that variation in long bone growth as well as dental age confounds consistent and reliable ageing of skeletal remains based on diaphyseal length. Assessment of changes in health and evaluation of methodological problems inherent to studies of skeletal growth from archaeological populations are discussed. Population comparisons for changes in general health are recommended over individual assessments.  相似文献   

15.
Moran's Index for spatial autocorrelation and localized index for spatial association have been widely applied in many research fields as the first step to explore and assess the spatial dependency in a set of geographic events. This article presents extensions to the equations for calculating global and localized spatial autocorrelation so to include the temporal attribute values of the geographic events being analyzed. The extended equations were successfully implemented and tested with a real world data set. In addition, simulated data sets were used to reveal how the extended equations performed. Beyond the usefulness of the extended equations, we suggest that care be taken with regard to assessing spatiotemporal patterns under the normality and randomization assumptions as different outcomes from different assumptions would require different approaches for interpretation.  相似文献   

16.
To date, most obsidian sourcing studies in the Andes have concentrated on the highlands and Titicaca Basin of far southern Peru and northern Bolivia. Toward achieving a more complete understanding of the region, this paper offers new data on the long-term prehistoric obsidian procurement and consumption patterns in the Andahuaylas region of the south-central Peruvian highlands. Obsidian sourcing data from Andahuaylas are particularly interesting since the area is centrally located among several important regional obsidian sources. A total of 94 obsidian samples from a range of sites of different temporal periods were chemically analyzed using portable X-ray fluorescence (PXRF), as well as laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS). The results demonstrate a number of interesting trends, the first of which is the long-term importance of the Potreropampa obsidian source to populations of the Andahuaylas region from at least the early Formative period (∼2500 BCE). Secondly, the results indicate that procurement strategies by local populations in Andahuaylas were primarily reliant on nearby (<150 km) obsidian sources. Finally, the paucity of more distant, yet widely exchanged, high quality obsidian (i.e., Chivay, Alca) confirm that as a region, Andahuaylas was more heavily connected economically (and likely culturally) with local areas to the south (Apurímac) and to the west (Ayacucho).  相似文献   

17.
Winds in the upper atmosphere, and their effect on the ionosphere, are reviewed with an emphasis on information useful to ionospheric studies. The winds are driven by pressure gradients from solar and auroral heating, with some forcing by tidal energy from below. Simple calculations which balance the pressure gradient by ion drag and Coriolis forces are generally unreliable, so large-scale numerical models of the coupled atmosphere and ionosphere are required. The accuracy of these global models is limited by uncertainties in the energy inputs at high latitudes and at the lower boundary (about 90 km). The best current wind data come from incoherent scatter radar or airglow installations, at a few sites and for only a few nights per month. Satellite data are also available for several years, and results to 1989 are incorporated in the global HWM90 model. This seems acceptable for determining mean winds at night, less good during the day, and least good in the southern hemisphere where few data were available. Plots are given to show the mean winds at different latitudes and longitudes, for use in ionospheric calculations.Meridional winds alter the height of the mid-latitude F layer, causing large changes in the effective loss rate. This is the major cause of observed seasonal changes, of differences between the hemispheres, and of changes at different longitudes. An increased knowledge of the winds is essential for further progress in F region studies. Ionospheric data provide the most promising route, using routinely scaled parameters. The simplest calculations compare observed peak heights, obtained from M (3000)F2, with the value ho predicted by simplified “servo” equations. Errors occurring for some hours after sunrise can be overcome using model results to define ho this allows rapid and accurate wind calculations at dip latitudes of 23–62°. Winds can also be obtained from full model calculations, designed to match observed values of peak height or density.  相似文献   

18.
This paper provides two archaeometric equations obtained by crystal–chemical parameters for dating human bone samples from the archaeological site of Nasca, Peru. Based on radiocarbon dating, the burials span from 500 BC to AD 1000. Crystal–chemical modifications in bone hydroxylapatite over time were compared with a twentieth century skeleton from Italy. Chemical analysis was carried out by means of electron microprobe along a profile from the periosteal to the endosteal border of the midshaft of four human femurs. The results indicate that the Ca/P ratio is linearly correlated with time according to the equation t=7880.68Ca/P−12805.90 (r=0.97; r2=0.95). Bone apatite X-ray powder diffraction analysis showed a systematic increase in the (002) reflection intensity with time, according to the equation t=250.49h/a−1961.86 (r=0.98; r2=0.97). The two independent archaeometric equations permit good accuracy in dating osteoarchaeological remains from the south coast area of Peru. © 1998 John Wiley & Sons, Ltd.  相似文献   

19.
The INDI experiment consisted of a series of joint observations between EISCAT and a Fabry-Perot interferometer (FPI) situated at Kiruna. The FPI measured the 630 nm neutral oxygen emission at eight positions on a 30° elevation circle, giving a spatial average of the neutral wind field with a time resolution of about 15 min. The radar performed a seven-position, near-meridional scan in a region common to the optical measurements. Such simultaneous observations of the ionised and neutral components of the Earth's atmosphere allow a study of the ion energy balance and the coupling between species. The first stage of the analysis was to derive the neutral wind from the EISCAT data using the simplified ambipolar diffusion and ion energy equations. This was then compared with the direct measurements from the FPI. There was good agreement between derived and measured meridional winds, but the zonal wind values, although showing the same trends, differed in magnitude by a factor of 3–5. The reasons for this are discussed. The meridional wind data was used to derive the ion-neutral collision frequency. This was a factor of 2 or 3 less than recent model values. Preliminary comparisons of the measured electron densities with the 630 nm emission intensity gave clues to the chemistry of the emission process.  相似文献   

20.
The eastern Mediterranean, with its long archaeological and historical records, provides a unique opportunity to study human responses to climate variability. We review paleoclimate data and reconstructions from the region with a focus on the last 6000 years. We aim to provide an up-to-date source of information on climate variability and to outline present limitations and future opportunities. The review work is threefold: (1) literature review, (2) spatial and temporal analysis of proxy records, and (3) statistical estimation of uncertainties in present paleoclimate reconstructions (temperature, °C). On a regional scale the review reveals a wetter situation from 6000 to 5400 yrs BP (note: all ages in this paper are in calibrated years before present (i.e. before 1950), abbreviated yrs BP, unless otherwise stated). This is followed by a less wet period leading up to one of fully-developed aridity from c. 4600 yrs BP. There is a need for more high-resolution paleoclimate records, in order to (i) better understand regional patterns and trends versus local climate variability and to (ii) fill the gap of data from some regions, such as the Near East, Greece and Egypt. Further, we evaluate the regional occurrence of a proposed widespread climate event at 4200 yrs BP. This proposed climate anomaly has been used to explain profound changes in human societies at different locations in the region around this time. We suggest that although aridity was widespread around 4200 yrs BP in the eastern Mediterranean region, there is not enough evidence to support the notion of a climate event with rapidly drying conditions in this region.  相似文献   

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