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1.
The conventional narrative regarding the American reception of George Perkins Marsh, author of Man and Nature (1864), is that his work and ideas were “lost,”“forgotten,” or “neglected” until Lewis Mumford “rediscovered” him and introduced him to geographers at the University of California‐Berkeley through The Brown Decades (Mumford [1931] 1955) and until Carl Sauer made him known to the profession at large beginning in 1938. This article upends the conventional narrative by looking at earlier references to Marsh's later versions of Man and Nature, which were published as The Earth as Modified by Human Action from 1874 to 1907. Analysis reveals that a number of geographers and historians cited these editions between 1875 and the early 1950s. Examining the legend of loss and rediscovery suggests the value of methods utilized in reception studies for research on the history of geography.  相似文献   

2.
Artificial neural networks were applied to simulate runoff from the glacierized part of the Waldemar River catchment (Svalbard) based on hydrometeorological data collected in the summer seasons of 2010, 2011 and 2012. Continuous discharge monitoring was performed at about 1 km from the glacier snout, in the place where the river leaves the marginal zone. Averaged daily values of discharge and selected meteorological variables in a number of combinations were used to create several models based on the feed‐forward multilayer perceptron architecture. Due to specific conditions of melt water storing and releasing, two groups of models were established: the first is based on meteorological inputs only, while second includes the preceding day's mean discharge. Analysis of the multilayer perceptron simulation performance was done in comparison to the other black‐box model type, a multivariate regression method based on the following efficiency criteria: coefficient of determination (R2) and its adjusted form (adj. R2), weighted coefficient of determination (wR2), Nash–Sutcliffe coefficient of efficiency, mean absolute error, and error analysis. Moreover, the predictors' importance analysis for both multilayer perceptron and multivariate regression models was done. The performed study showed that the nonlinear estimation realized by the multilayer perceptron gives more accurate results than the multivariate regression approach in both groups of models.  相似文献   

3.
CO2 and temperature records at Mauna Loa, Hawaii, and other observation stations show that the correlation between CO2 and temperature is not significant. These stations are located away from big cities, and in various latitudes and hemispheres. But the correlation is significant in global mean data. Over the last five decades, CO2 has grown at an accelerating rate with no corresponding rise in temperature in the stations. This discrepancy indicates that CO2 probably is not the driving force of temperature change globally but only locally (mainly in big cities). We suggest that the Earth''s atmospheric concentration of CO2 is too low to drive global temperature change. Our empirical perception of the global warming record is due to the urban heat island effect:temperature rises in areas with rising population density and rising industrial activity. This effect mainly occurs in the areas with high population and intense human activities, and is not representative of global warming. Regions far from cities, such as the Mauna Loa highland, show no evident warming trend. The global monthly mean temperature calculated by record data, widely used by academic researchers, shows R2=0.765, a high degree of correlation with CO2. However, the R2 shows much less significance (mean R2=0.024) if calculated by each record for 188 selected stations over the world. This test suggests that the inflated high correlation between CO2 and temperature (mean R2=0.765-0.024=0.741) used in reports from the Intergovernmental Panel on Climate Change (IPCC) was very likely produced during data correction and processing. This untrue global monthly mean temperature has created a picture:human emission drives global warming.  相似文献   

4.
Book Reviews     
Leinbach, Thomas R. and Brunn, Stanley D. (eds.) Worlds of E‐Commerce: Economic, Geographical, and Social Dimensions Calthorpe, Peter and Fulton, William The Regional City: Planning for the End of Sprawl Furuseth, Owen J. and Lapping, Mark B. (eds.) Contested Countryside: The Rural‐Urban Fringe in North America Sharp, Joanne P. Condensing the Cold War: Reader's Digest and American Identity Gleeson, Brendan and Low, Nicholas (eds.) Governing for the Environment: Global Problems, Ethics, and Democracy Isenberg, Andrew The Destruction of the Bison: An Environmental History, 1750 – 1920 Albert, Donald P., Gesler, Wilbert M. and Levergood, Barbara (eds.) Spatial Analysis, GIS, and Remote Sensing Applications in the Health Sciences Wright, Dawn J. and Bartlett, Darius J. (eds.) Marine and Coastal Geographical Information Systems Jankowski, Piotr and Nyerges, Timothy Geographic Information Systems for Group Decision Making: Towards a Participatory Geographic Information Science Gerber, Rod and Chuan, Goh Kim (eds.) Fieldwork in Geography: Reflections, Perspectives, and Actions Craige, Betty Jean Eugene Odom: Ecosystem Ecologist and Environmentalist Lowenthal, David George Perkins Marsh: Prophet of Conservation Schroeder, Richard Shady Practices: Agroforestry and Gender Practices in The Gambia Lovell, W. George A Beauty that Hurts: Life and Death in Guatemala Lichtenberger, Elisabeth Austria: Society and Regions  相似文献   

5.
Scientists often turn to farmers to understand soil management. This process reveals differences and overlaps between local and scientific soil knowledge but rarely considers women and gender issues. This paper examines men's and women's local knowledge of soils in upland, smallholder farms in two villages in Mindanao, the Philippines, using focus group discussions, semi‐structured household interviews, field visits, GIS and soil testing. Farmers' field areas were calculated and delineated based on their perceptions of the different types of soils on their land. Men and women chose the same plots for what they considered their best soil but differed on what they felt were their worst. The fertility of the soils that women considered to be the best and worst was not significantly different from that of the men's respective choices. There was a difference in fertility, however, between the best and worst soils regardless of gender. Although soil fertility analyses showed that the women's chosen soils were similar to men's, analyses of qualitative data showed that their knowledge of soils was different and was based in part on a gendered division of labour. A multidisciplinary approach helped bridge the gap between sociocultural and physical research.  相似文献   

6.
《自然地理学》2013,34(3):251-268
Scientists have been formally studying the consequences of human action at least since Buffon and Humboldt in the 1700s. In 1864, Marsh published Man and Nature, a comprehensive synthesis documenting how people had been transforming Earth. This prominent catalogue of how people disturb Nature's harmonies was updated by Marsh in 1874 and by geographers in 1956 and 1990. Today the leading conceptions of human-environmental interaction are similar to Marsh's theme that people are the disturbers of Nature's harmonies. Effects of human action are considered using conceptions such as direct/indirect, intentional/accidental, and beneficial/detrimental. For a fresh approach, physical geographers could consider action more directly. Human action can be studied as any other process is. Systems concepts and energy flows used to evaluate natural forces can also be used to evaluate human forces. The centennial of the Association of American Geographers is an appropriate time to reflect on how physical geographers have been studying human-environmental interactions and to consider new approaches.  相似文献   

7.
Leinbach, Thomas R. and Brunn, Stanley D. (eds.) Worlds of E-Commerce: Economic, Geographical, and Social Dimensions

Calthorpe, Peter and Fulton, William The Regional City: Planning for the End of Sprawl

Furuseth, Owen J. and Lapping, Mark B. (eds.) Contested Countryside: The Rural-Urban Fringe in North America

Sharp, Joanne P. Condensing the Cold War: Reader's Digest and American Identity

Gleeson, Brendan and Low, Nicholas (eds.) Governing for the Environment: Global Problems, Ethics, and Democracy

Isenberg, Andrew The Destruction of the Bison: An Environmental History, 1750 – 1920

Albert, Donald P., Gesler, Wilbert M. and Levergood, Barbara (eds.) Spatial Analysis, GIS, and Remote Sensing Applications in the Health Sciences

Wright, Dawn J. and Bartlett, Darius J. (eds.) Marine and Coastal Geographical Information Systems

Jankowski, Piotr and Nyerges, Timothy Geographic Information Systems for Group Decision Making: Towards a Participatory Geographic Information Science

Gerber, Rod and Chuan, Goh Kim (eds.) Fieldwork in Geography: Reflections, Perspectives, and Actions

Craige, Betty Jean Eugene Odom: Ecosystem Ecologist and Environmentalist

Lowenthal, David George Perkins Marsh: Prophet of Conservation

Schroeder, Richard Shady Practices: Agroforestry and Gender Practices in The Gambia

Lovell, W. George A Beauty that Hurts: Life and Death in Guatemala

Lichtenberger, Elisabeth Austria: Society and Regions  相似文献   

8.
This paper focuses on Hong Kong's Gravesweeping Festivals, Qingming and Chongyang. The practices carried out in urban cemeteries at these Festivals are over two thousand years old, and represent “time out” from modern “clock time”. They are examined in the context of Giddens' (1985) reworking of Hägerstrand's time‐space geography, and of Douglas' (1966) discussion of pollution. It is suggested that the cemeteries are regarded as dangerous places because they represent liminal spaces. Giddens' dimension of span enables a distinction to be made between, on the one hand, the long‐established cultural significance of the grave, and, on the other, the recentness of the urban cemetery. The dimension of form(redefined from Giddens' original concept), applied to some details of cemetery landscapes, reveals the “worlds apart” of the non‐material worlds of the spirits and of fengshui. By considering the Festivals in the light of Giddens' dimension, character, it emerges that the Gravesweeping Festivals are, as they have been for centuries, firmly embedded in Hong Kong's social system, where routines of ancestor veneration continue to renew and strengthen the family bonds that are at the heart of Confucian values. Furthermore, their continued observation may well represent practices that are of deep ontological significance to the predominantly immigrant community of Hong Kong.  相似文献   

9.
Abstract

An increased use of artistic literature as a resource in both teaching and research is evident in geography. With the growing interest of some scholars in the behavioral aspects of geography, traditional resources are being supplemented with more humanistic, subjective information sources. In historical geography, for example, literature is a particularly suitable resource for studies of man's role in past geographies and of human perception of past environments.1 Specialists in regional geography and area studies also have shown a growing appreciation of such sources.2 A parallel and related development has occurred in geographic education. In many different courses, but particularly in those dealing with regions, literature has become a recommended resource. The purposes of this paper are (1) to review the relevance of the novel as a resource for geographers and (2) to suggest that a current novel, Centennial, by James A. Michener,3 particularly warrants consideration for use in courses on the historical geography of the United States.  相似文献   

10.
The weights-of-evidence model (a Bayesian probability model) was applied to the task of evaluating landslide susceptibility using GIS. Using landslide location and a spatial database containing information such as topography, soil, forest, geology, land cover and lineament, the weights-of-evidence model was applied to calculate each relevant factor's rating for the Boun area in Korea, which had suffered substantial landslide damage following heavy rain in 1998. In the topographic database, the factors were slope, aspect and curvature; in the soil database, they were soil texture, soil material, soil drainage, soil effective thickness and topographic type; in the forest map, they were forest type, timber diameter, timber age and forest density; lithology was derived from the geological database; land-use information came from Landsat TM satellite imagery; and lineament data from IRS satellite imagery. Tests of conditional independence were performed for the selection of factors, allowing 43 combinations of factors to be analysed. For the analysis of mapping landslide susceptibility, the contrast values, W + and W -, of each factor's rating were overlaid spatially. The results of the analysis were validated using the previous landslide locations. The combination of slope, curvature, topography, timber diameter, geology and lineament showed the best results. The results can be used for hazard prevention and land-use planning.  相似文献   

11.
Carbon and oxygen isotope ratios of bone apatite were measured in 14 endothermic and ectothermic vertebrates native to the Chihuahuan Desert and collected in June and July of 1999 and 2000. The δ8O values of most reptiles were very high, up to 44‰ (standard mean ocean water (SMOW), some of the highestδ18 O values ever measured for an animal. The δ18O values of rodents and birds were lower (32±5‰ vSMOW), and the earless lizard Holbrookia maculata were the lowest of all species analysed (25‰). Omnivorous grasshopper mice (Onychomys torridus) had lower δ18O values than granivorous rodents. Results from oxygen analysis likely reflect variation in diet and body water flux differences between endotherms and ectotherms. Carbon isotope analysis revealed a dramatic shift in diet from C3 plants in 1999 to C4 plants in 2000 in most rodents and birds. Kangaroo rats and reptiles did not change, having a constantδ13 C value indicative of a C3-based diet in both years. This suggests reliance on winter annual plant seed caches for kangaroo rats, but not other rodents. The carbon isotope data can be explained in terms of seasonal differences within and between years in the timing and intensity of the seasonal rainfall events, and the productivity of summer and winter annual plants. This study illustrates that stable isotope analysis is a powerful method for tracking dietary change and feeding behavior in desert vertebrates.  相似文献   

12.
ABSTRACT. Wilhelmine Germany had a powerful economy and, after 1898, began construction of a fleet to challenge Great Britain's global power. This article analyses Germany's cultural “will to power” in the period through the eyes of the avant‐garde, Munich‐published weekly magazine Simplicissimus as it examined the series of security crises between 1896 and the outbreak of war in 1914. The magazine was no fan of Wilhelmine militarism, its principal artist having been jailed for criticism of the kaiser, but it showed a deep support for Germany's rise to power on moral grounds. Many illustrations dealt with global power projection through the navy and the need for a suitable security partner within Europe. Its illustrators depicted Great Britain as an immoral world power only Germany might check and France as its preferred security partner to keep Europe at peace.  相似文献   

13.
Research Paper     
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14.
The paper focuses on early Holocene tree growth and alpine tree-limits in the northernmost Swedish Scandes (Lapland). Megafossil wood remnants in peats and lakes were searched for over a large area at elevations high above the modern tree-limits. Wood of Pinus sylvestris, Betula pubescens spp. tortuosa and Alnus incana was discovered near the shore of a small lake (999 m a.s.l.) c. 500 m higher than today's tree-limit of Pinus sylvestris in this region. Radiocarbon dating yielded values of unprecedented age, c. 8500–8100 14C years BP for all three species and in addition 5400–4500 14C years BP for Betula and Alnus. The highest position of the Pinus tree-limit occurred during the early Holocene, which compares well with the situation reconstructed by megafossils in the southern Scandes. It now appears that the long-term tree-limit and climate histories are broadly the same in entire mid- and northern Fennoscandia. Corrected for glacio-isostatic land uplift, the tree-limit record suggests that the summers were c. 2.4°C warmer than today at 8500 14C years BP . A dry continental climate with substantial seasonal contrasts is likely to have prevailed during this period, which restricted the occurrence of glaciers and glacier activity. Most circumstances point to the overriding importance of the Milankovitch orbital theory for pacing or forcing the long-term postglacial climate change. The results are inconsistent with most inferences based on pollen, certain macrofossil records and general circulation simulations. These proxy environmental histories have frequently advocated a mid-Holocene thermal optimum and an oceanic and humid climate in northern and western Fennoscandia during the early Holocene. The uncovered discrepancy between the outcome of the objective and factual megafossil method and more subjective/inferential microfossil methods should be important for Quaternary plant ecology in general, stressing the usefulness of megafossil studies.  相似文献   

15.
Floods are a frequently occurring calamity in deltaic Bangladesh. This paper aims to assess the temporal expansion of waterbodies during flooding using geospatial techniques. Several water indices were applied to classify the satellite images at various temporal scales. Among them, the Normalized Difference Water Index (NDWI) showed the highest correlation (r = 0.831; where p = 0.01) with rainfall data. Specifically, the NDWI results showed that perennial waterbodies measured 37 km2 and 60 km2 in Sunamganj District in 2017 and 2019, respectively. The area of waterbodies notably increased 52-fold from March to April (37 km2 to 1958 km2) during the pre-monsoon flash flood of 2017. During the July 2019 monsoon flood, waterbodies started to extend after May and flooded 2784 km2 in area. NDVI analysis showed that in 2019, floodwater submerged 361.7 km2 of vegetation cover. At the same time, the Surma River's flooding resulted in a 73.9 per cent inundation of the total area of the Sunamganj District. We hope that this study will provide better understanding of the varying nature of floods that occur in the low lying bowl shaped Haor region which will in turn assist the government with flood mitigation.  相似文献   

16.
Geography has discovered resilience theory, a body of thought about ecological change that initiated with C.S. Holling in the 1970s. We describe the similarities and differences between resilience theory and a geographical treatise, Thomas Vale's (1982) book Plants and People. Vale's work draws more from the tradition of field botany and plant succession than from the theoretical and mathematical ecology that prompted Holling's ideas. Yet like resilience theory, Vale's model of ecological change emphasized multiple states, the threshold transitions between them, and their irreversibility. Each described how forests and rangelands can flip between stability domains in response to altered fire regimes, modified grazing pressures, and climate change. Plants and People also recognized the dual nature of stability encapsulated in Holling's formalization of engineering and ecological resilience. Although resilience theory predates Vale's work and retains primacy through its citation record, we show how their partial consilience promotes a more critical understanding of resilience theory and the ways in which models, scale, and human values influence our comprehension of ecological change.  相似文献   

17.
《自然地理学》2013,34(5):474-482
Our knowledge of winter leaf conductance and transpiration rates during the winter and early spring is especially weak for Pinus strobus L. (eastern white pine). Hence, the present study was conducted to: (1) measure and examine the winter leaf conductance and transpiration rates among 10 P. strobus trees to supply preliminary data for an understudied tree species; and (2) investigate whether observed leaf conductance and transpiration rates are large enough to merit incorporation into existing water balance models. The fieldwork was conducted at the Fair Hill Natural Resources Management Area in northeastern Maryland (39°42'N, 75°50'W) using a Li-Cor 1600M Steady State Porometer. Meteorological data were acquired from a continuously recording meteorological station on-site. Meteorological data were recorded at five-minute intervals to ensure that weather conditions could be temporally sequenced with porometer readings. The 10 co-occurring P. strobus sample trees were of similar age and health on uniform soils in an open field. Winter and early spring leaf conductance values of the selected trees reached 20 mmol m-2 s-1, whereas transpiration reached 0.13 mmol m-2 s-1. Results of the study indicate that there is statistically significant differences in leaf conductance rates among co-occurring P. strobus trees (H = 16.74, p = .05). Since the upper winter leaf conductance and transpiration rates measured in this study overlap with growing season leaf conductance and transpiration values reported by others, it is suggested that winter leaf conductance of and transpiration from P. strobus trees are significant enough to incorporate into water balance calculations.  相似文献   

18.
Terminus geometry, ice margins, and surface elevations on Rabots glaciär were measured using differential GPS during summer 2011 and compared with those similarly measured in 2003. Glacier length over the eight years decreased by ～105 m corresponding to 13 m a?1, a rate consistent with ice recession over the last several decades. Measured changes in surface elevations show that between 2003 and 2011 the glacier's volume decreased by ～27.6 ± 2.6 × 106 m3, or 3.5 ± 0.3 × 106 m3 a?1. This compares favorably with an estimate of ?28.1 ± 2.6 × 106 m3 based on a mass‐balance approach. The rate of volume loss appears, however, to have significantly increased after 2003, being substantially greater than rates determined for the intervals 1959–80, 1980–89, and 1989–2003. This increase corresponds to a sustained interval of more negative summer balances. Previous work suggests that as of 2003 Rabots glaciär had not yet completed its response to a ～1°C warming that occurred c. 1900, and thus the current marked increase rate of ice loss might reflect the effect of recent, or accelerated regional warming that occurred during the last decade superimposed on its continued response to that earlier warming.  相似文献   

19.
William Bunge's Fitzgerald: Portrait of a Revolution, initially published in 1971, is an enthralling verbal and visual account of the historical and geographical development of a one-square-mile neighborhood in Detroit. The original analysis of the Fitzgerald neighborhood was based on intensive field-based research conducted in a theoretical context of race and racism. The research reported here maintains that context but updates Fitzgerald's account of the neighborhood's built environment through a spatial analysis that uses parcel-by-parcel data generated in Google Earth and Google Street View instead of data collected in the field. Current spatial patterns of deterioration in the built environment are similar to those described in Fitzgerald, but positive sites are also apparent and often colocated with negative ones.  相似文献   

20.
This commentary is a response to an article by Jay R. Harman in the November 2003 issue of The Professional Geographer. I argue that Harman's claim that scholarly disciplines offer social “returns” in a competitive “market” obscures the fundamentally political nature of how social resources are allocated and how social needs are defined. Harman would have us subordinate scholarly research to agendas set elsewhere, by politicians and other powerful interests, but I argue that such a vision would turn geographers into mere technicians. A healthier role for the discipline is for geographers to seek ways of asserting intellectual leadership and of shaping social agendas along more humane and socially just lines.  相似文献   

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