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Urban Community Garden Agrodiversity and Cultural Identity in Philadelphia,Pennsylvania, U.S. 
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下载免费PDF全文 Hamil Pearsall Sheila Gachuz Marcel Rodriguez Sosa Birgit Schmook Hans van der Wal Maria Amalia Gracia 《Geographical review》2017,107(3):476-495
Considerable research has examined the social, cultural, economic, and community benefits of urban gardening. Few studies, however, have empirically assessed factors that influence urban community garden agrodiversity or its relationship to these dimensions of gardening. We conducted an interdisciplinary study of agrodiversity and cultural identity, based certain markers of identity, including how people see themselves with respect to race, ethnicity, or place of origin, in community gardens in Philadelphia, Pennsylvania. We conducted fifty‐six semistructured interviews with gardeners with different cultural identities in eight community gardens on their motivations for urban community gardening during 2014. We conducted plant inventories of the corresponding garden plots and found 104 cultivated edible and ornamental species and 28 varieties representing 34 families. We find that although gardens with culturally diverse gardeners did not have higher species richness, the cultural identity of the gardeners influenced species selection and reason for gardening. Further, the structure, design and species composition of garden plots reflected the identities of garden members. These finding have implications for the recent institutionalization of urban agriculture into city land policies in Philadelphia and other cities in North America. 相似文献
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A conservative solute tracer experiment was conducted in Indian Creek, a small urban stream in Philadelphia, Pennsylvania to investigate the role of subsurface properties on the exchange between streamwater and the hyporheic zone (subsurface surrounding the stream). Sodium Bromide (NaBr) was used as a conservative tracer, and it was monitored in the surface water at two stations and in the upper bed sediments (shallow hyporheic zone extending from 7.5 to 10 cm below the streambed). The hydraulic conductivity (K) of the upper bed sediments and the lower bed sediments (10–12.5 cm below the streambed) was measured in situ. High tracer concentrations were observed in the upper layer at locations where the hydraulic conductivity of the upper layer was larger than that of the lower layer. Low concentrations in the upper layer were observed in the converse case. A statistically significant relationship between the mass retained in the upper layer and the difference of K values between layers was observed. 相似文献
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The development of effective, and economical pre-development waste rock management plans requires an accurate estimate of the quality of drainage generated during mining. This study was conducted to determine if a simple accelerated rock weathering method with lower capital and personnel costs can be used in lieu of the elaborate and costly ASTM method to predict the quality of drainage generated. It involves subjecting rock samples to a constant relative humidity and temperature for 7 days and leach flooding the weathered samples on the 7th day. The acid production rate from the new weathering method correlates quite well with the net neutralization potential generated from the standard acid-base accounting procedure (R2=0.940) which has been demonstrated to be correct 90% of the time in assessing overburden quality, and a mineralogical method (R2=0.924). For investigators interested in generating weathering kinetic parameters, the simple and less costly accelerated weathering method is proposed. 相似文献
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Development of probability distributions for urban hydrologic model parameters and a Monte Carlo analysis of model sensitivity 下载免费PDF全文
下载免费PDF全文 This paper proposes an approach to estimating the uncertainty related to EPA Storm Water Management Model model parameters, percentage routed (PR) and saturated hydraulic conductivity (Ksat), which are used to calculate stormwater runoff volumes. The methodology proposed in this paper addresses uncertainty through the development of probability distributions for urban hydrologic parameters through extensive calibration to observed flow data in the Philadelphia collection system. The established probability distributions are then applied to the Philadelphia Southeast district model through a Monte Carlo approach to estimate the uncertainty in prediction of combined sewer overflow volumes as related to hydrologic model parameter estimation. Understanding urban hydrology is critical to defining urban water resource problems. A variety of land use types within Philadelphia coupled with a history of cut and fill have resulted in a patchwork of urban fill and native soils. The complexity of urban hydrology can make model parameter estimation and defining model uncertainty a difficult task. The development of probability distributions for hydrologic parameters applied through Monte Carlo simulations provided a significant improvement in estimating model uncertainty over traditional model sensitivity analysis. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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OpenStreetMap (OSM) is an online public access database that allows for the collaborative collection of local geographic information. We employ this mapping technology to discuss a new social theory of poverty that moves away from income poverty to an economy that directly produces individuals' basic needs. Focusing on urban farming in Philadelphia as an example, we use OSM to support the argument that money, land, labor, and capital do not limit food production in the city. OSM is a type of “commons” that allows community members to depict features of interest to them that might otherwise be underrepresented in official or commercially produced maps such as Google Maps. Using the concept of facilitated volunteered geographic information (VGI) we developed an open framework for combining residents' local knowledge of food resources with expert guidance in data input. We believe this helps overcome problems with ad hoc data submission efforts to which collaborative online projects are susceptible. The program for “tagging” food resources in OSM was deployed in a public “map-a-thon” event we organized in Philadelphia, bringing together technical experts and food enthusiasts. To share the results, we present the Philly Fresh Food Map as an interactive online Web map that can be used and updated by the public. 相似文献
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《Urban geography》2013,34(2):118-129
This article explores the historical, economic, and social factors that shape the recent migration of middle-class Blacks to low-income, urban, Black neighborhoods. It focuses on the meanings associated with this pattern of Black gentrification and the extent to which this residential pattern is consistent with previous models of urban gentrification. Using three years of ethnographic data from a low-income neighborhood in Philadelphia that has experienced an increase in Black middle-class residents, I conclude that this pattern of neighborhood change is distinct from previous models of urban gentrification. In this article, I argue that Black gentrification represents a unique set of opportunities and constraints that produce a group of middleclass African Americans willing to invest their social, economic, and cultural capital into improving the quality of life for low-income Black neighborhoods and their residents. 相似文献
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Kristen B. Crossney 《The Professional geographer》2013,65(2):153-170
U.S. housing policy strengthens the local specificity of capital through support for homeownership and the mortgage lending industry. As access to capital and homeownership rates have grown, predatory lending has emerged as a significant danger to homeowners and their surrounding communities. The geographic distribution is not well understood, likely due to the unavailability of mortgage data to identify instances of predatory lending. This article examines the spatial distribution of predatory lending in Philadelphia, Pennsylvania, using public mortgage and property data. Predatory lending is spatially clustered within the city, suggesting a spatial component of abusive lending patterns not previously addressed. U.S. housing policy and intervention strategies designed to prevent and reduce the incidence of predatory lending should address the spatial aspects of predatory lending to target efforts and prevent weakening local connections between capital and communities. 相似文献
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Alan Wiig 《Urban geography》2016,37(4):535-553
Smart city initiatives have been adopted by cities worldwide, proposing forward-looking, technological solutions to urban problems big and small. These policies are indicative of a digitized urban condition, where social and economic exchange rely on globalized telecommunications networks, and governance strategies follow suit. Propelled through events such as IBM’s Smarter Cities Challenge, the smart city acts as a data-driven logic urban change where widespread benefit to a city and its residents is proposed, masking the utility of these policies to further entrepreneurial economic development strategies. In this article, I present a case study of the Digital On-Ramps initiative that emerged from IBM’s policy-consultation in Philadelphia. The initiative proposed a social media-style workforce education application (app) to train up to 500,000 low-literacy residents for jobs in the information and knowledge economy, but even as the city’s mayor declared the project a success, it did not meet expectations. This essay argues that the rhetoric of intelligent, transformative digital change works much more to “sell” a city in the global economy than to actually address urban inequalities. 相似文献
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《Geoforum》2017
Predatory lending and abusive practices arose as a serious danger by increasing the threat of foreclosure and bankruptcy and decreasing the equity accumulated in a housing unit, reducing many of the economic benefits of homeownership. This article describes the characteristics of areas who likely suffered from abusive mortgage lending using Census data, Home Mortgage Disclosure Act data, and publicly recorded mortgage data. A proxy measure of predatory lending is developed based on the loan-to-value (LTV) ratio and state anti-predatory lending regulations, and represents excessively leveraged properties. Discriminant analysis is used to distinguish between areas with these highly leveraged properties and other parts of the City of Philadelphia. The residuals are mapped to evaluate the spatial dimension of the discriminant models across the city. This examination of demographic and socioeconomic characteristics informs efforts to mitigate the consequences and prevent future occurrences of both predatory lending and other manifestations of inequality by viewing it as a spatial and neighborhood phenomenon. 相似文献