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Elvin K. Wyly 《The Professional geographer》1996,48(4):431-444
This study analyzes commuting trends in a relatively vibrant setting during the 1980s to determine (a) how labor market segmentation correlates with differences in the spatial dimensions of local labor markets, and (b) whether this link represents a direct spatial effect, independent of earnings, travel mode, and part-time work. I use 1980 and 1990 PUMS data to analyze changes in racial and gender divisions in the workforce, and I develop an estimate of work trip distance to adjust for different travel modes. For all groups except white men, employment in a job “typical” of one's gender and racial group is associated with more localized commutes, but this effect is strongly mediated by variations in earnings and part-time work. Using a covariance structure model to control for these effects, I find no independent link between segmentation and longer commutes among African Americans. Earnings and commute distances remained unchanged over the decade for African Americans, providing no evidence of a purely spatial mismatch manifest in lengthening work trips without corresponding wage gains. The spatial dimensions of an employment mismatch for inner-city minorities are concealed through the replacement of production jobs by poorly paid service work in the expanding downtown economy of a vibrant regional center. 相似文献
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Geographies of the United States in the Year 2004* 总被引：2，自引：2，他引：0
Elvin K. Wyly 《The Professional geographer》2004,56(1):91-95
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J. A. Dearing R. T. Jones J. Shen X. Yang J. F. Boyle G. C. Foster D. S. Crook M. J. D. Elvin 《Journal of Paleolimnology》2008,40(1):3-31
A 6.48 m sediment core sequence from Erhai lake, Yunnan Province, provides a multi-proxy record of Holocene environmental
evolution and human activity in southwest China. These sedimentary records provide proxy time series for catchment vegetation,
flooding, soil erosion, sediment sources and metal workings. They are complemented by independent regional climate time-series
from speleothems, archaeological records of human habitation, and a detailed documented environmental history. The article
attempts to integrate these data sources to provide a Holocene scale record of environmental change and human–environment
interactions. These interactions are analysed in order to identify the roles of climate and social drivers on environmental
change, and the lessons that may be learned about the future sustainability of the landscape. The main conclusions are: lake
sediment evidence for human impacts from at least 7,500 cal year BP is supported by a terrestrial record of cultural horizons
that may extend back to ∼9,000 cal year BP. A major shift in the pollen assemblage, defined by detrended correspondence analysis,
at ∼4,800 cal year BP marks the transition from a ‘nature-dominated’ to a ‘human-dominated’ landscape. From 4,300 cal year
BP, a change in river discharge responses may signal the beginning of hydraulic modification through drainage and irrigation.
Major increases in disturbed land taxa and loss of forest taxa from 2,200 cal year BP onward, also associated with the start
of significant topsoil erosion, register the expansion of agriculture by Han peoples. It is also the start of silver smelting
linked to trade along the SW Silk Road with Dali becoming a regional centre. Peak levels of disturbed land taxa, topsoil and
gully erosion are associated with the rise and fall of the Nanzhao (CE 738–902) and Dali (CE 937–1253) Kingdoms, and the documented
environmental crisis that occurred in the late Ming and Qing dynasties (CE 1644–1911). The crisis coincides with a stronger
summer monsoon, but exploitation of marginal agricultural land is the main driver. These historical perspectives provide insight
into the resilience and sustainability of the modern agricultural system. The largest threat comes from high magnitude-low
frequency flooding of lower dry farmed terraces and irrigated valley plains. A sustainable future depends on reducing the
use of high altitude and steep slopes for grazing and cultivation, maintaining engineered flood defences and terraces, and
anticipating the behaviour of the summer monsoon.
This article is based on a keynote address delivered by John Dearing at the 10th International Paleolimnology Symposium, June
2006, Duluth, Minnesota, USA. 相似文献
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Coping with Complexity: Adaptive Governance in Desert Australia 总被引：1，自引：0，他引：1
Governance in Aboriginal settlements in desert Australia is changing at an unprecedented rate. Aboriginal leaders and community
managers describe the change as bewildering, with ever-revolving agents and agencies and increasing quantities of administration.
Governments are preoccupied with finding linear ‘solutions’ to new conceptualisations of the ‘problem’ and packaging these
for top-down implementation. However, governance in practice involves multi-dimensional interactions of a complex system,
which are difficult to predict, let alone to control for outcomes. Through the lens of complex adaptive systems (CAS) theory,
this paper argues that there is potential to improve governance as an adaptive system through three principles that enhance
local feedback: (1) application of the subsidiarity principle to different levels in the governance system would realise a
better match between decentralised functions and local capacity; (2) connectivity would improve information flows and relationships
between agents in the system, as a necessary precursor for informed decision-making; and (3) accountability, when taken beyond
simplistic notions of financial reporting, would identify power relationships across the system and indicate where agents
may exercise greater influence in the system. Consideration of these principles will help promote a shift from the perspective
that assumes the system to be linear and manageable from the top-down to a perspective that embraces the notion of adaptive
governance as a means of recognising the capacity of agents to influence the system that they inhabit. 相似文献
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The North Atlantic right whale (Eubalaena glacialis) is the most critically endangered large cetacean and is threatened by vessels that travel in their habitats and migration paths. A need to address the endangered population status of the right whale emerges as current management mandates have proven ineffective at preventing vessel-strikes to right whales and current rates of strike-induced mortality can slow or prevent recovery of the species. This paper identifies the need for an internationally acceptable management strategy to minimize vessel-strikes to right whales in Canadian waters. 相似文献
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This paper records the findings at a temporary exposure at Thorpe St Andrew near Norwich, Norfolk, UK in Early and early Middle Pleistocene Crag deposits. The British Geological Survey (BGS) describes the particular formation exposed as Norwich Crag consisting of Early Pleistocene shallow marine sediments. The section shows a succession of sorted sands and gravels overlain by a sandy diamicton. Based on field evidence and clast analysis, the sands and gravels are interpreted as the product of point bar and overbank sedimentation and represent the product of a river cutting into and aggrading within the more widespread shallow marine deposits. Composition of the sediments indicates derivation, primarily from Wroxham Crag Formation, with a contribution from Norwich Crag. The sandy diamicton is interpreted as late Middle Pleistocene Corton Till that is recorded in the area. A distinct pattern of colour changes at the top of the sands and gravels is interpreted as a soil that developed on the fluvial sediments before being overridden by the glacier that deposited the Corton Till. The existence of the fluvial sediments within the regional shallow marine deposits suggests that a fall of sea-level, possibly due to climate cooling, while the elevation of the sediments and the adjacent Crag implies that the site has been uplifted since sedimentation. This is the first observation of terrestrial sediments within the shallow marine Crag. The paper also makes a contribution to understanding the diagenetic processes that give deposits within this region some distinctive colour and sediment patterns. 相似文献
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Elvin Wyly 《Urban geography》2013,34(5):669-690
With a mantra that ‘nobody is as smart as everybody,’ Google maintains giant databases that enable unprecedented quantitative analysis of a social world that is now majority urban. A Wall Street web-based broker offers an App that promises to turn ‘thoughts into trades.’ Economists and marketers now use evolutionary theory in ‘neuroimaging’ brain scans of consumer behavior. The United States Air Force now trains more joystick-maestro drone pilots than old-fashioned Do-the-Right-Stuff human fighters and bombers. In this article, I suggest that these trends signal a troubling reincarnation of an aggressive Right-wing (post)positivist zombie reanimated by global, digitized neoliberalism. The long-forgotten revolutionary project launched by Auguste Comte in 1822 was hijacked and corrupted after his death, and now we confront a hybrid cyborg zombie, a dehumanized, automated adaptation to the post-structuralist situated knowledges of consumer sovereignty. #Comtebot: The positivist era is right now; the question is what kinds of politics it will have. 相似文献
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Elvin Delgado 《社会与自然资源》2017,30(7):797-811
ABSTRACTThis article provides a critical analysis of the process involved in transforming small-scale artisanal production of solar salt into large-scale industrial production by Produsal in Los Olivitos Wildlife Refuge and Fishing Reserve in Lake Maracaibo, Venezuela. In doing so, it highlights the socioecological impacts resulting from this process in the wetland and the fishing community of Ancón de Iturre. Using political economy of nature as a theoretical framework, especially notions of the formal subsumption of nature, materiality of natural resources, and the commodification of nature, this article explores how the biophysical characteristic of salt and the ecosystem where it is contained present a specific set of natural obstacles for its production; the different strategies used by Produsal to overcome these obstacles; and the social and ecological contradictions embedded in the process. 相似文献
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