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1.
AMENITY MIGRATION IN THE U.S. SIERRA NEVADA*   总被引:1,自引:0,他引:1  
ABSTRACT. Since 1960 California's Sierra Nevada counties have ranked among the regions with the strongest relative population growth in the state. Reassessment of peripheral areas has been the main force driving population and settlement growth in the central Sierra Nevada of California and Nevada, termed “amenity migration” or “counterurbanization.” This study analyzes the impacts of amenity migrants—“urban refugees”—on socioeconomic conditions in high‐mountain regions. We define these regions as the “High Sierra,” comprising zones at elevations more than 1,800 meters above sea level. People who migrate to the High Sierra tend to be white and well educated, with considerable household earnings. Unlike the population in the foothills, these migrants are not senior citizens. Their demand for periodic or permanent residences has caused housing prices to increase enormously. As a result, a majority of homes are now priced well beyond the reach of local salaries, which may lead to potential conflict between locals and newcomers. The massive settlement expansion in high‐mountain areas requires a new approach to land‐use planning, one that takes functional regions into account. Therefore, it is expedient to reassess existing jurisdictional boundaries.  相似文献   

2.
Spartina sp. (“townsendii” and anglica) was introduced in the Ho Bugt area at Esbjerg in 1931. The investigation is based on a study of a sample area on the peninsula Skallingen during the years 1957, 1960, 1965 and 1970, on litterature and on a survey of the whole bay in 1971. The colonization in the different parts of the bay is described.

“Spartina shows an extremely plastic morphological response to the varying conditions of tidal submergence and exposure on different parts of the marsh. This enables it to occupy a wide range of zones occupied in other areas by a series of different plant communities.” (Ranwell, 1964).

“It has, in fact, not only taken possession of a vacant ecological niche, but has spread from this to form a serious competition to other salt marsh species of long standing.” (Goodman a.o., 1959).  相似文献   

3.
Challenges arising from changing demographics, expensive housing, and precarious labor have prompted recent interest in the residential geographies of young adults. Yet, despite attention to young adults' diverse housing pathways, I argue that greater focus is needed on the place-based and spatial underpinnings and effects of particular housing pathways: Connections to urban processes of “youthification”—the concentration of young adults in dense neighborhoods—and “studentification”—whereby an area becomes dominated by university students—remain underdeveloped, as do linkages between these phenomena and gentrification. I explore these connections through a critical review of extant literature to show that the enactment of some pathways is associated with particular urban processes, which might foreclose certain pathways for other individuals. Finally, I identify three crucial areas of inquiry: (1) how youthification, studentification, and gentrification interact; (2) how these processes shape and are shaped by diverging individual housing pathways; and (3) how differences among young adults such as race, ethnicity, and gender intersect with age in the course of these processes.  相似文献   

4.
This study analyzes metropolitan dynamics in a small country with an “island state” context of closed boundaries, using commuting data and mobile phone tracking data. We examine whether the Israeli context encourages the formation of a monocentric “metropolitan state,” characterized by increasing links between localities throughout the country and its principal metropolitan node (Tel Aviv)—rather than with secondary metropolitan areas—and by fuzzy, overlapping metropolitan boundaries. Commuting data from the 1995 and 2008 censuses show that metropolitan expansion processes in Israel are gradual. Mobile phone tracking data for 2013 reveal similar patterns, confirming the urban structure’s stability and the reliability of tracking data as a means of assessing metropolitan processes. The “island state” context supports growing monocentricity, but, when it comes to commuting and travel for other purposes, Israel is not yet a metropolitan state; metropolitan boundaries are not as fuzzy and rapidly changing as expected.  相似文献   

5.
Abstract

This article analyzes the impact of the much-heralded Youngstown 2010 Plan and the enacting of a program of “controlled” or “managed” shrinkage. It is argued that while the program of redevelopment has had an impact on Youngstown and its national image, it represents an exclusionary project that has centered on redeveloping downtown areas and neglected many city neighborhoods which continue to experience high levels of unemployment, vacancy, and crime. The analysis is situated in relation to the contemporary literature on “shrinking cities.” Youngstown's experience raises critical questions regarding the nature of the challenges facing shrinking cities, the constraints on actions available to them due to state and federal funding, and the coherence of the concept of “smart shrinkage.”  相似文献   

6.
Portland, Oregon, is renowned as a paradigmatic “sustainable city.” Yet, despite popular conceptions of the city as a progressive ecotopia and the accolades of planners seeking to emulate its innovations, Portland’s sustainability successes are inequitably distributed. Drawing on census data, popular media, newspaper archives, city planning documents, and secondary source histories, we attempt to elucidate the structural origins of Portland’s “uneven development,” exploring how and why the urban core of this paragon of sustainability has become more White and affluent while its outer eastside has become more diverse and poor. We explain how a “sustainability fix”—in this case, green investment in the city’s core—ultimately contributed to the demarcation of racialized poverty along 82nd Avenue, a major north–south arterial marking the boundary of East Portland. Our account of structural processes taking place at multiple scales contributes to a growing body of literature on eco-gentrification and displacement and inner-ring suburban change while empirically demonstrating how Portland’s advances in sustainability have come at the cost of East Portland’s devaluation. Our “30,000 foot” perspective reveals systemic patterns that might then guide more fine-grained analyses of particular political-socio-cultural processes, while providing cautionary insights into current efforts to extend the city’s sustainability initiatives using the same green development model.  相似文献   

7.
基于生态补偿空间选择的基本原理,从区域范畴、资金分配、生态价值3个方面,解析了新疆重点生态功能区的基本特征,并利用“效益成本比瞄准”法、“生态补偿优先等级”法定量分析新疆生态补偿优先等级。结果表明:“生态补偿优先等级”中,新疆生态补偿优先等级与转移支付资金分配基本一致,因忽略环境因素,使得优先补偿等级未获得充分的生态转移支付资金;“效益成本比瞄准”法中,因忽略民生因素和环境因素,新疆生态补偿优先等级与转移支付资金呈现不对等关系,但这一方法,能更好地解读后期生态补偿的区域选择。在分配转移支付资金时,应综合环境、民生因素,均衡生态补偿优先等级与转移支付资金,提高转移支付资金的使用效率,推进新疆生态环境持续优化。  相似文献   

8.
Policy Boosterism,Policy Mobilities,and the Extrospective City   总被引:1,自引:1,他引:0  
Abstract

This study develops the notion of “policy boosterism,” a subset of traditional branding and marketing activities that involves the active promotion of locally developed and/or locally successful policies, programs, or practices across wider geographical fields as well as to broader communities of interested peers. It is argued that policy boosterism is (1) an important element of how urban policy actors engage with global communities of professional peers and with local residents, and (2) a useful concept with which to interrogate and understand how policies and policy knowledge are mobilized among cities. A conceptualization of policy boosterism and its role in global-urban policymaking is developed by combining insights from the burgeoning “policy mobilities” literature with those of the longstanding literature on entrepreneurial city marketing. It is supported by illustrative examples of policy boosterism in Vancouver: the city's Greenest City and Green Capital initiatives, the use of the term “Vancouverism” among the city's urban design community, and demonstrations of new urban technologies during the 2010 Winter Olympics that were used to market a particular vision of the city's governance to people from elsewhere, but also—crucially—to local audiences. The article concludes by highlighting four foci that might frame future work at the intersections of policy boosterism and policy mobilities.  相似文献   

9.
戴其文  赵雪雁 《地理学报》2010,65(4):494-506
以甘南州草地生态系统水源涵养服务为例,构建以机会成本、交易成本和实施成本为参数的参与成本模型确定生态补偿标准。基于生态补偿资金效率的考虑,构建以土地所有者提供的生态系统服务、土地所有者的参与成本和生态系统服务受损风险为参数的空间选择模型,以乡镇为研究单元,对生态补偿区域进行选择,采用聚类分析将全州划为5大等级补偿区:优先补偿区、次级优先补偿区、次级补偿区、临界补偿区和潜在补偿区或可能补偿区,并对各类补偿区的特征进行了分析。构建生态补偿额基尼系数与生态补偿资金效率评价模型,分别评价了补偿额在受偿群体和补偿区域中分配的公平性、合理性与不同等级补偿区的补偿效率。结果表明:①以草地生态系统服务功能的价值(4776.4元/hm2·a)和机会成本(621.3元/m2·a)作为补偿标准的上下限,结合参与成本确定甘南州草地生态系统补偿标准为1999.8元/hm2·a;②草地生态系统的补偿优先度与生态重要性、生态脆弱性呈现出吻合趋同的状态,即草地生态系统优先补偿区既是高效补偿区,又是重要生态区和生态脆弱区;③受偿者(草地生态系统水源涵养服务供给者)得到的补偿额有明显不均衡状态,而在补偿区域(草地生态系统)上的分配却处于绝对平均范围内;④草地生态系统补偿区的优先等级次序与补偿效率吻合,即草地生态系统的优先补偿区的补偿效率最高,每元获取的草地生态系统水源涵养服务为38.18,是临界补偿区的14.68倍;次级优先补偿区的效率仅次于优先补偿区,每元补偿的生态系统服务为21.02。  相似文献   

10.
近年来,中国高铁步入快速建设期,而高铁建设的重要目的之一就是客货分流。高铁客运专线的建设大大地提升了客运能力,从而可以释放既有线路的运输能力于货物运输。但是高铁客运的票价也高于既有线路,同时由于普通列车车次的减少,使得居民出行可能要被迫选择票价更高的高铁,这种现象称作“被高铁”。本文对媒体关注的“被高铁”现象进行了理性分析,以京沪高铁沿线城市为例,根据2015年1月1日列车时刻表数据计算出的时间节省的货币成本与小时工资(时间价值)作比较,并结合高铁车次比重,计算了不同城市的居民“被高铁”的可能性。研究发现:①很多“城市对”之间都存在时间节省的货币成本高于小时工资的情况,“被高铁”现象较为普遍;②“被高铁”的可能性在50%左右;③各城市“被高铁”的程度有较大差异,京沪高铁沿线城市的“被高铁程度”整体呈现出“两头低,中段高,长三角相对较低”的特征。研究认为,虽然从目前来看,京沪高铁沿线城市的普通列车班次减少不明显,但如果进行较大幅度调整,很多低收入旅客出行时可能会被迫选择高铁,并将带来负面的社会影响。本文的理性分析可为列车班次的调整方案提供参考。  相似文献   

11.

Any sustainable resource utilization plan requires evaluation of the present and future environmental impact. The present research focuses on future scenario generation of environmental vulnerability zones based on grey analytic hierarchy process (grey-AHP). Grey-AHP combines the advantages of grey clustering method and the classical analytic hierarchy process (AHP). Environmental vulnerability index (EVI) considers twenty-five natural, environmental and anthropogenic parameters, e.g. soil, geology, aspect, elevation, slope, rainfall, maximum and minimum temperature, normalized difference vegetation index, drainage density, groundwater recharge, groundwater level, groundwater potential, water yield, evapotranspiration, land use/land cover, soil moisture, sediment yield, water stress, water quality, storage capacity, land suitability, population density, road density and normalized difference built-up index. Nine futuristic parameters were used for EVI calculation from the Dynamic Conversion of Land-Use and its Effects, Model for Interdisciplinary Research on Climate 5 and Soil and Water Assessment Tool. The resulting maps were classified into three classes: “high”, “moderate” and “low”. The result shows that the upstream portion of the river basin comes under the high vulnerability zone for the years 2010 and 2030, 2050. The effectiveness of zonation approach was between “better” and “common” classes. Sensitivity analysis was performed for EVI. Field-based soil moisture point data were utilized for validation purpose. The resulting maps provide a guideline for planning of detailed hydrogeological studies.

  相似文献   

12.
Resisting urban renewal in Istanbul   总被引:1,自引:1,他引:0  
In this article I examine grassroots responses to state-directed urban renewal in two poor neighborhoods in Istanbul. Through detailed analysis of resident perspectives and urban association tactics, I explore various factors that shape the trajectories of resistance to urban renewal, including solidarity networks, levels of participation and trust in local neighborhood associations, strength of neighborhood identity, extra-local support, and the traditions and channels of negotiation with state actors. I argue that these factors are articulated by a distinct “politics of compensation”—a term that I borrow from Ananya Roy—that is particular to the contemporary neoliberal condition. I find that grassroots mobilizations in Istanbul do not necessarily operate in opposition to neoliberalism; in fact, many struggles remain within the conceptual space of neoliberalism and its cost-benefit calculations. These findings contribute to the emerging literature on struggles against urban renewal in the global south.  相似文献   

13.
Municipal governments produce a seemingly endless supply of urban strategic plans, which purport to define the city by making claims on its future development trajectories. Critics note that this claimsmaking on “the city” renders it conceptually vacuous and overextended. Yet it is essential to question the degree to which speculative policymaking is merely rhetorical. Discursive claimsmaking on the city through strategic planning documents is an important technique in urban politics—a form of targeted simplification that benefits particular stakeholders by defining the city around sites in which they are invested. Bids to host sporting “mega-events” like the Olympic Games are a case in point: event planning corporations routinely make claims on the city, which strategically simplify its forms and processes, often by defining the city in ways that mediate between particular land investment projects and broad visions for citywide development. The implication is that claimsmaking on the city through urban strategic planning is intentionally simplistic and acts as an ideological practice for justifying urban development projects.  相似文献   

14.
The prevailing pattern in much of the social sciences, including geography and criminology, relies on count data. “Hotspots” — geospatial areas with disproportionally more crime than the rest of the city — are usually identified by the number of events in these areas. Yet no attention is given to their severity, or any other weighting system of harm, despite the common-sense view that not all crimes are created equal. To illustrate the value of focusing on harm in addition to count data, we turn to a spatial analysis of crime by observing crime concentrations (hotspots) against harm concentrations (harmspots), across fifteen councils in the United Kingdom. The definition of “harm” is based on the Sentencing Guidelines for England and Wales, as each crime category (n = 415) attracts a different severity weight. Both “hotspots” and “harmspots” are defined as being at least 2 standard deviations from the mean distribution within each city: This procedure creates comparable datasets. The data suggest that half of all crime events are concentrated within 3% of all street segments in the selected councils, yet harm is even more heavily concentrated, with half of all harm located in just 1% of each council [OR = 3.49; 95% CI 3.268–3.728]. The intra-unit variance was also reduced by approximately half — from 0.75% to 0.45%. We discuss the implications of using harm, in addition to counts, for research and policy by arguing that a shift in focus is required both for the development of theories and for cost-effective prevention strategies.  相似文献   

15.
深圳农民工集聚空间的演变特征及影响机制   总被引:6,自引:3,他引:3  
周春山  杨高  王少剑 《地理科学》2016,36(11):1643-1653
以2000年、2010年人口普查数据和2008年珠江三角洲外来农民工问卷调查为基础数据,以街道为单元,运用数理统计分析和GIS空间技术揭示深圳农民工集聚空间演变特征及其影响机制。研究发现: 深圳农民工以青年为主体,具有受教育水平高、职业转型模式多样、留城意愿较低和社会空间分异度较高等特征。 农民工规模呈现西北部最高、中部其次、沿海最低的地带性分布规律,农民工高密度地区主要分布在工业集中区和城市中心区;热点区(高聚集区)集中在西部和北部的宝安区和龙华新区,冷点区(低聚集区)则分布在南部的中心城区,与传统制造业布局相一致。 农民工空间演化格局相对稳定,全市农民工分布重心逐步向西北偏移;全市农民工集中度略有上升,热点区基本稳定,冷点区有所扩大;农民工人口密度高值由“1个高中心+1个外围中心”逐步演变为“1个高中心+2个外围中心”;农民工空间变化差异较大,增长演变类型呈多样化。 深圳农民工分布的时空演变特征与常住人口存在较为明显的差异。 农民工集聚空间的分布演变受住房因素、就业机会、交通条件、社会网络、城市规划共同影响。  相似文献   

16.
Abstract

Fire, either natural or man-caused, has influenced the pattern of vegetation in numerous areas over the earth. Factors that contribute to potential damage to either the vegetation and/or environment are examined. Since the extent of damage varies, a fire can be destructive or useful. The use of “prescribed” fire in land management accomplishes several desired objectives, one of which is the perpetuation of certain fire-climax vegetation types, such as pines and some grasses. In those pine-forested areas where fire is regularly used in management, a related benefit is the reduction of hazardous natural fuels, which results in fewer catastrophic wildfires. Air pollution due to forest burning is also considered.  相似文献   

17.
It is commonly assumed that the development of tourist attractions, the formulation of tourism policies, and the marketing of destination areas are dictated by the needs and interests of foreign visitors. What is ignored is the role that local factors and agencies play in these processes. This paper explores the way local and non-local factors are responsible for shaping the form and function of tourism development. Drawing upon the case of Singapore, I examine the country's heritage tourism phenomenon as the outcome of “local” and “global” forces. This argument is elaborated along three lines of enquiry. They include: (a) a study of the government's tourism policies; (b) an examination of marketing and promotional strategies; and (c) a look at a particular urban landscape—the Little India Historic District. To conceptualize the global-local nexus, the paper embraces two bodies of theory. They are the “locality concept” advanced by industrial geographers in the 1980s, and writings on “globalism/localism” by cultural/economic geographers in the 1990s. Both theoretical discussions reinforce the argument that place uniqueness need not be sacrificed as a result of globalization. They also provide a way of viewing tourism geographies as the product of global and local forces.  相似文献   

18.
Zhang  Qiming  Wang  Enyuan  Feng  Xiaojun  Wang  Chao  Qiu  Liming  Wang  Hao 《Natural Resources Research》2021,30(2):1817-1834

With the increasing depth of underground engineering, the risk of coal–rock dynamic disasters such as rockburst is becoming more and more serious and complex, which seriously threatens the safety of coal resource, mine production and the surface ecological environment. However, the existing risk indices and methods used for evaluating rockburst risk cannot be fully applied to deep goal seam group (DCG) mining. For the safe exploitation of coal resources, in this paper, based on statistical analyses of 300 cases of rockburst, six new indices are proposed for evaluating rockburst risk in the DCG, namely dip angle, moisture content, stability of coal seam, advancing speed of working face, disturbance factors and support patterns. In addition, the influence of multiple factors coupling and superposition on rockburst risk was considered. Thus, the Comprehensive Index Method of rockburst risk of Deep Coal seam Group (DCG–CIM) based on analytic hierarchy process was established. Finally, rockburst risk in the evaluation area was quantitatively assessed into four grades, including “No rockburst risk”, “Weak rockburst risk”, “Medium rockburst risk” and “Strong rockburst risk”. Taking the 2233 working face of Hengda Coalmine as an example, the evaluation results show that the ranges of 0–184 m, 224–284 m, 324–384 m, 424–484 m, 524–584 m and 594–624 m from terminal line of haulage roadway on 2233 working face were the medium rockburst risk zones, which are in accordance with the on-site impact damage results and are more accurate than the traditional method. The DCG–CIM can consider more inducing factors and obtain more accurate and reliable evaluation results and is more suitable for deep coal seam group mining.

  相似文献   

19.
Abstract

One important finding that emerges from the literature on Business Improvement Associations (BIAs) is that businesses are, quite often, not as unified and homogeneous as what is proclaimed by their “business voice”—their collective values, visions, and ethos. What has not received full consideration is the nuanced, complex, and complicated manner in which the business voice is produced and sustained. Intended as a corrective to this void, I explore the ways that BIAs in Toronto and Vancouver have attended to problems of public disorder. I suggest that the ways BIAs frame and construct public disorder as problematic to businesses, and the ways this is publicized, can be understood as a well-orchestrated and choreographed performance that encompasses both a front and back region. The front region tells the story that public disorder is inimical to businesses and does so by relying on particular tactics and techniques. The back region reveals a more complicated picture—first, with respect to the ways the issues are framed and (re) produced, which also has the effect of reinforcing and sustaining the narrative that is presented in the front region, and second, with respect to the fragility and fractured state of the “business community” that is often in disarray and characterized by disunity, disagreements, and disharmony  相似文献   

20.
中国区域水资源系统韧性与效率的发展协调关系评价   总被引:1,自引:0,他引:1  
孙才志  孟程程 《地理科学》2020,40(12):2094-2104
在界定水资源系统韧性概念的基础上,综合应用赋权法、SBM-DEA模型及发展协调度模型对2000—2016年全国31个省区的区域水资源系统的效率、韧性以及两者之间的发展协调关系进行评价。结果如下:① 中国区域水资源系统效率整体上处于非有效区,在研究期间呈现出在波动中上升的趋势。② 中国区域水资源系统韧性的平均值为0.39,总体水平较低,研究期间整体上呈波动上升趋势。③ 中国区域水资源系统效率与韧性的发展度总体呈现平稳上升—较快上升—急剧下降—上升的趋势,呈倒“U”型发展;协调度在研究期间呈现波动中上升趋势,大部分省区的发展度较好,而协调度较弱。④ 2000—2016年,水资源效率与韧性的发展协调度一直维持着“东?中?西”阶梯式递减格局,失调省区的数量降低,初级协调、中级协调、良好协调省区的数量逐渐提升,整体向协调趋势发展;空间格局上呈现由2000年倒“E”型对称式分布格局向如今北部围绕天津、中部围绕上海、南部围绕广东的三级格局演变,格局分布与中国三大经济区基本吻合,可知中国水资源系统效率与韧性的发展协调水平与经济发展水平之间有明显的关系。  相似文献   

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