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101.
102.
Samuel M. Otterstrom 《The Professional geographer》2013,65(1):147-149
Ryan, James R. Picturing Empire: Photography and theVisualization of the British Empire Sizoo, Edith (ed.) Women's Lifeworlds: Women's Narratives on Shaping their Realities. Teaford, Jon Post-Suburbia Government and Politics in the Edge Cities. Warhus, Mark Another America: Native American Maps and the Historyof Our Land Yeung, Y. M. and Chu, David K. Y. (eds.) Guangdong: Survey of aProvince Undergoing Rapid Change Young, E. M. World Hunger 相似文献
103.
Rusty A. Gonser Ryan R. Jensen Samuel E. Wolf 《Applied geography (Sevenoaks, England)》2009,29(4):527-532
Deer–vehicle collisions (DVCs) are a constant problem in North America that cost millions of dollars of damage and loss of human life. This study investigated the spatial relationship of DVCs for a county in western Indiana using nearest neighbor analysis, chi-square test of independence, and a landscape metric: the percentage of like adjacencies. The study was able to show that DVCs are not randomly located, and that habitat type and structure may play an important role in the location of DVCs. 相似文献
104.
ZHANG Xuhui LI Huan GONG Zheng ZHOU Zeng DAI Weiqi WANG Lizhu Samuel DARAMOLA 《地理学报(英文版)》2021,31(12):1852-1872
It is common to obtain the topography of tidal flats by the Unmanned Aerial Vehicle(UAV) photogrammetry,but this method is not applicable in tidal creeks.The residual water will lead to inaccurate depth inversion results,and the topography of tidal creeks mainly de-pends on manual survey.The present study took the tidal creek of Chuandong port in Jiangsu Province,China,as the research area and used UAV oblique photogrammetry to reconstruct the topography of the exposed part above the water after the ebb tide.It also proposed a Trend Prediction Fitting (TPF) method for the topography of the unexposed part below the water to obtain a complete 3D topography.The topography above the water measured by UAV has the vertical precision of 12 cm.When the TPF method is used,the cross-section should be perpendicular the central axis of the tidal creek.A polynomial function can be adapted to most shape of sections,while a Fourier function obtains better results in asym-metrical sections.Compared with the two-order function,the three-order function lends itself to more complex sections.Generally,the TPF method is more suitable for small,straight tidal creeks with clear texture and no vegetation cover. 相似文献
105.
Determinants and characteristics of female migration: a case study of Salem City in Tamil Nadu,India
Nangia S Samuel MJ 《Population geography : a journal of the Association of Population Geographers of India》1983,5(1-2):34-43
A random sample of 521 male and 481 female migrants surveyed in Salem city in Tamil Nadu, India, during 1980-1981 was analyzed on the basis of a classification related to reasons (association, marriage, distress, and voluntary) for migration. Women were found to outnumber males in associational migration, both in rural to urban and urban to urban streams. They also formed almost all the marriage migrants. They were more numerous in distress migration as well. There were, however, comparatively few women among voluntary migrants. The incidence of illiteracy among migrant women was generally high, except for voluntary migrants who had completed high school. The share of working women was not negligible, but in most cases present work status was achieved after migrating. 相似文献
106.
Combined observations of hourly soil temperature and electric potential, the latter converted to a relative index of soil-water solute concentration, yield information on the physical chemistry of near-surface frost effects. Solute concentration near the descending 0° C isotherm in the refreezing active layer above permafrost is divided into three distinct zones: (1) an ion-enriched zone in the unfrozen active layer that precedes the penetrating freezing front; (2) an ion-purified desorbed zone at the freezing front that is the source region of the downward-expelled ions and water; and (3) a hydrologically isolated subfreezing zone of enhanced solute concentration located above the freezing isotherm. High-frequency fluctuations superimposed on these general patterns are traceable to vapor migration driven by surface thermal fluctuations. These effects diminish at temperatures below about -0.4° C, as permeability decreases with soil-ice formation. The combined temperature-solute concentration time series is used to develop sorption curves for the frozen organic and mineral soils, and indicates that approximately half of the pore water present in the mineral soil at -0.4° C had not been converted to ice at -6° C. Gradual soil desiccation over winter appears to result from outward vapor diffusion, possibly through soil cracks. [Key words: Alaska, active layer, frozen ground, soil temperature, soil water, permafrost.] 相似文献
107.
U-Pb isotopic thermochronometry of rutile, apatite and titanite from kimberlite-borne lower crustal granulite xenoliths has been used to constrain the thermal evolution of Archean cratonic and Proterozoic off-craton continental lithosphere beneath southern Africa. The relatively low closure temperature of the U-Pb rutile thermochronometer (~400-450 °C) allows its use as a particularly sensitive recorder of the establishment of "cratonic" lithospheric geotherms, as well as subsequent thermal perturbations to the lithosphere. Contrasting lower crustal thermal histories are revealed between intracratonic and craton margin regions. Discordant Proterozoic (1.8 to 1.0 Ga) rutile ages in Archean (2.9 to 2.7 Ga) granulites from within the craton are indicative of isotopic resetting by marginal orogenic thermal perturbations influencing the deep crust of the cratonic nucleus. In Proterozoic (1.1 to 1.0 Ga) granulite xenoliths from the craton-bounding orogenic belts, rutiles define discordia arrays with Neoproterozoic (0.8 to 0.6 Ga) upper intercepts and lower intercepts equivalent to Mesozoic exhumation upon kimberlite entrainment. In combination with coexisting titanite and apatite dates, these results are interpreted as a record of postorogenic cooling at an integrated rate of approximately 1 °C/Ma, and subsequent variable Pb loss in the apatite and rutile systems during a Mesozoic thermal perturbation to the deep lithosphere. Closure of the rutile thermochronometer signals temperatures of °C in the lower crust during attainment of cratonic lithospheric conductive geotherms, and such closure in the examined portions of the "off-craton" Proterozoic domains of southern Africa indicates that their lithospheric thermal profiles were essentially cratonic from the Neoproterozoic through to the Late Jurassic. These results suggest similar lithospheric thickness and potential for diamond stability beneath both Proterozoic and Archean domains of southern Africa. Subsequent partial resetting of U-Pb rutile and apatite systematics in the cratonic margin lower crust records a transient Mesozoic thermal modification of the lithosphere, and modeling of the diffusive Pb loss from lower crustal rutile constrains the temperature and duration of Mesozoic heating to °C for ka. This result indicates that the thermal perturbation is not simply a kimberlite-related magmatic phenomenon, but is rather a more protracted manifestation of lithospheric heating, likely related to mantle upwelling and rifting of Gondwana during the Late Jurassic to Cretaceous. The manifestation of this thermal pulse in the lower crust is spatially and temporally correlated with anomalously elevated and/or kinked Cretaceous mantle paleogeotherms, and evidence for metasomatic modification in cratonic mantle peridotite suites. It is argued that most of the geographic differences in lithospheric thermal structure inferred from mantle xenolith thermobarometry are likewise due to the heterogeneous propagation of this broad upper mantle thermal anomaly. The differential manifestation of heating between cratonic margin and cratonic interior indicates the importance of advective heat transport along pre-existing lithosphere-scale discontinuities. Within this model, kimberlite magmatism was a similarly complex, space- and time-dependent response to Late Mesozoic lithospheric thermal perturbation. 相似文献
108.
109.
Samuel Walker 《Urban geography》2016,37(2):163-182
Both Vancouver, British Columbia, and Detroit, Michigan, have significant and growing urban agriculture movements. In this article, I follow recent work investigating the connection between urban agriculture and neoliberalization to determine how these local governments have used urban agriculture in narratives of economic development to selectively pursue a sustainability fix. I analyze how different regimes of local governance have influenced the urban agriculture movements, leading to local, hybridized fixes that adapt to different material and discursive contexts in each place. I argue that in both cities, urban agriculture has radical potential as a grassroots response to economic and environmental injustice, but has also been enrolled as a device by the local state in which the primary goal of sustainability planning becomes enhanced economic competitiveness. Pursuing an agenda of food justice requires examining the larger context and effects of municipal involvement with food movements. 相似文献
110.
A Study on the Surface Wettability of Clastic Rocks with Potential Application for CO2 Storage Sites
Umar Bappah Adamu Gholami Raoof Raza Arshad Downey William Samuel Sarmadivaleh Mohammad Shah Afroz A. Nayak Prasanta 《Natural Resources Research》2020,29(3):2051-2061
Natural Resources Research - There have been many studies carried out in the past decades attempting to develop strategies for a safe injection of CO2 into storage sites without leakage and... 相似文献