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1.
We state that land use is under constant pressure, no matter if land-use changes take place in growing or shrinking cities. Land-use changes witness multiple interdependencies between environmental, social and economic factors. In urban areas land is highly exposed to accelerating consumption which makes it a scarce and precious resource. Therefore we need transformative processes to deal with land use in a more sensible and responsible way. We define urban transformations as fundamental, multi-dimensional changes in urban land-use patterns, population developments, infrastructures, governance regimes as well as established values, norms and behaviours. A central focus is on land use and its changes to supply ecosystem services as key driver for quality of life. Most important for us is that transformative processes are highly dynamic and non-linear, thus affecting functions of urban land uses in different ways and with varying consequences. In this sense, governance research is a decisive component to implement our research in practice. With this viewpoint we want to contribute to a debate on land-use changes in alternating growing and shrinking cities to foster appropriate development responses for urban transformations towards sustainability.  相似文献   

2.
Urbanization induces spatial and environmental changes. Monitoring and understanding the nature of these changes is crucial to achieving sustainable urban development imperatives. To this end, this paper examines the evolution and spatio-environmental impacts of rapid urbanization in two major metropolitan regions of Ghana—Accra-City Region and the Greater Kumasi Sub-Region. The analysis uses Landsat satellite data and landscape metrics to examine land use transitions and to characterize the emergent landscapes over the last three decades. The results show that built-up land has increased significantly in these metropolitan regions largely at the expense of environmental land cover classes. The expansion process follows a general trend where the historical-core zones were initially sites of rapid land cover conversion to built-up, with settlements in the suburban and peripheral zones expanding in recent years and becoming integrated into the conterminous urban areas of the metropolitan regions. The analysis also uncovered a unique, dynamic and complex process whereby the urban-open-space class, being in a permanent state of flux, mediates transitions between built-up land and vegetation and vice versa. The metric-based land use transformation analysis shows that the landscape of the metropolitan regions has fragmented because of an increased expansion and aggregation of patches of built-up land in the core areas and leapfrog, sprawling expansion in the outlying suburban and peripheral zones. The paper concludes on the need for integrative urban growth management strategies that brings together spatial planning and environmental resource governance to avert the negative consequences on the natural environment of unfettered urban expansion.  相似文献   

3.
In the past few decades, urbanisation has become a major phenomenon in European cities, thus representing one of the key human land cover changes with socio-economic and environmental impacts. In the Lisbon metropolitan region it is estimated that 17% of natural and farmland have been transformed into artificial areas. Since the end of 1990s, specific EU guidelines have been issued to contain urban sprawl and preserve agricultural land. Spatial planning in Portugal obviously is integrating these assumptions into the statutory land-use master plans. But what is the performance of this land use planning system regarding land cover evolution itself? Based on the Lisbon metropolitan region (LMR), one of the major areas of urban growth in Portugal, we examine spatio-temporal land cover patterns between 1990 and 2007 by integrating cross-matrix analysis, spatial metrics, and gradient analysis. Additionally, we overlay these land cover dynamics with municipal master plans that regulate land development in order to assess the compliance levels of this land-use regulatory system. Results indicate that: artificial areas are growing by coalescence and/or by scattered development along an urban–rural gradient; agricultural land is reducing and fragmentation is increasing to enlarge peri-urban spaces; there are high levels of conversion of agricultural land into urban land in protected areas, thus showing a lack of compliance to the land use regulatory system visible in the existing gaps between the original land-use assignments of the master plan and the actual developments.  相似文献   

4.
In less-developed countries, the major global pressures of rapid urbanization and climate change are resulting in increased vulnerability for urban dwellers. Much of the climate impact is concentrated in urban and coastal areas, as urban development spreads into areas that are hazard-prone. Often this development is dominated by poor quality homes in informal settlements or slums on informal or illegally occupied or subdivided land.Urban development needs to be more climate-resilient to meet the post millennium development goals (MDGs) agenda. One of the elements in achieving climate-resilient urban development is the degree to which climate change adaptation and risk management are mainstreamed into two major elements of land governance, viz. securing and safeguarding of land rights, and planning and control of land-use.This paper proposes ways in which the growth of human settlements can be better managed through responsible governance of land tenure rights, and effective land-use planning to reduce vulnerability, provide adequate access to safe land and shelter, and improve environmental sustainability.  相似文献   

5.
Urban planners are increasingly interested in agriculture around cities and have to decide whether to maintain or not areas of agricultural land use within and close to growing cities. There is therefore a need for researchers to design tools to guide public decision-making on land use. Various approaches, originating from different disciplines, may be adopted in this respect. We designed an interdisciplinary research program in order to test two related concepts: the “sustainability” and the “multi-functionality” of agriculture. We show that these concepts provide a useful framework for obtaining appropriate knowledge about urban agriculture, which urban planners could apply in real situations. In close collaboration with urban planners, we applied an interdisciplinary research methodology, based on common farm surveys and territorial approaches, to the Antananarivo area (Madagascar). The main functions analyzed were the food production and environmental roles of urban agriculture. Two aspects of sustainability were assessed: the farm sustainability and the territorial sustainability, with expert scores. This approach identified a wide diversity of farming systems that performed differently, depending on their intra- or suburban location. The food supply function appeared to be important not only for fresh produce but also for rice consumption. The function of protection against flooding is now important and this importance will increase with climate change. A diagnosis of sustainability was made and discussed with urban planners: several farming systems and zones were identified in which agriculture was considered important as a means of maintaining or developing the food supply, employment and incomes, and even landscape or environmental quality. We also identified other areas in which poor production conditions and/or the negative effects of urbanization on agriculture jeopardized its sustainability. This methodology appeared to be useful for determining the most appropriate role of urban agriculture in the land-use planning of this city. Our study raises new questions on the subject and should lead to more focused research programmes. We discuss several points of interest and the limitations and possible extension of this method.  相似文献   

6.
Public policies play a vital role in shaping our cities. However, the impact of public policies on the spatial expansion of urban areas needs to be better understood in order to achieve better policy outcomes. During the period of China’s economic reform, the central government of China has made many changes in three sets of public policies—regional development policies, the household registration (hukou) system, and urban land and housing market policies—to promote coordinated development of small, medium and large cities. This study aims to examine the effects of these public policy changes on urban expansion across 265 Chinese cities at or above prefecture level. We first quantify the spatial patterns of urban areas and evaluate the extent of urban sprawl of the 265 cities from 1995 to 2015 using multi-temporal land cover data. These cities are classified into six categories according to a city tier system used in China. Through a set of individual fixed-effects models, we then explore how changes in the three sets of policies have influenced urban expansion differently across different-tier cities. Results show that sprawling patterns of urban expansion, which have been more prominent in small and medium sized cities since 2000, are associated with shifts in policies to support stronger economic and population growth as well as real estate development. Our findings highlight the need for policymakers to take a holistic approach by considering the size of cities together with their social, environmental, and economic characteristics in order to minimise inequality and achieve coordinated urban development goals.  相似文献   

7.
In efforts to promote transitions to sustainability in city-regions, government and nongovernment actors throughout the world are devising comprehensive sustainability strategies and implementing a variety of environmental policies. Social actors in many city-regions view forest stewardship as an important element of this integrated approach. Generally, urban sustainability goals are guided by the principles of ecological integrity, environmental quality, social equity, social inclusion, and social justice. In other words, sustainable urban development should foster a good quality of life for all by providing equitable access to adequate economic opportunity, housing, education, public services, ecosystem services, and environmental amenities. Governance structures should pursue these goals democratically with legitimacy, transparency, and accountability. Effective sustainability planning and management depend on the reliability of land-use monitoring and modeling approaches. They also require field-based, qualitative empirical research to understand the complex social dynamics that are invisible from space. The aim of this paper is to encourage international, cross-disciplinary dialogue on the conceptual, theoretical, methodological, and practical groundwork necessary to effectively carry out metropolitan land-change science, particularly for rapidly expanding small- and medium-sized cities in developing countries. I begin by presenting the paper's central conceptual and theoretical framework. Next, I explore existing analytical and methodological approaches to the study of land-use dynamics in metropolitan regions. After a brief discussion of specific opportunities and challenges for collaborative, interdisciplinary research in support of metropolitan land-change science, I conclude by proposing a four-part agenda for coordinated investigation of tropical and subtropical forest recovery in city-regions worldwide.  相似文献   

8.
Sustainable cities have, since the early 1990s, been the leading global paradigm of urbanism thanks to the different models of sustainable urban form proposed as new frameworks for the redesigning and restructuring of urban places to make urban living more sustainable. The compact city is the most preferred model of sustainable urbanism for responding to the challenges of sustainable development. However, despite the benefits claimed by the advocates of this model, its critics highlight a number of conflicts and contentions. This is coupled with several problems, issues, and challenges considering the very fragmented picture that arises of change on the ground in the face of urbanization. In this context, it has been suggested that the compact city needs to embrace and leverage what advanced ICT has to offer so as to improve, advance, and maintain its contribution to sustainability. With the above in regard, this paper provides a comprehensive state–of–the–art review of compact urbanism as a set of planning and development practices and strategies, focusing on the three dimensions of sustainability and the significant, yet untapped, potential of big data technology for enhancing such practices and strategies under what is labelled ‘data–driven smart sustainable urbanism.’ This paper identifies compactness, density, diversity, mixed land use, sustainable transportation, and green space as the prevalent design strategies of the compact city. At the heart of this model is the clear synergy between the underlying strategies in terms of their cooperation to produce combined effects greater than the sum of their separate effects as regards the tripartite value of sustainability. Indeed, this paper corroborates that the compact city is justified by its ability to contribute to the environmental, economic, and social goals of sustainability. Nevertheless, the economic goals seem to dominate over the environmental and social goals, notwithstanding the general claim about the three sustainability dimensions being equally important and mutually dependent. Further, this paper reveals that big data technology holds great potential for enhancing compact urbanism with respect to sustainability. This thorough review of and critique on the existing work on the compact city provides a reference for researchers and practitioners in related communities and the necessary material to inform these communities of the latest developments in the field of compact urbanism and its relation to data–driven smart urbanism. This work serves to inform various urban stakeholders about the benefits of data-driven smart solutions for advancing sustainability.  相似文献   

9.
Urbanization results in increasing impervious surfaces with the potential to threaten fragile environments and heighten flood risks. In the United States, research on the social processes driving urbanization has tended to focus on the twenty-first century, but less is known about how temporal trends arose from the spatial layout of the urban land upon which this growth was founded. To address this gap, we present a novel interdisciplinary synthesis using neighborhood-level census data in tandem with a satellite-derived annual land cover change time series to assess the role of race, affluence, and socioeconomic status in shaping spatio-temporal urbanization in the Houston metropolitan area from 1997−2016. Results from cross-sectional and temporal regression models indicate that while social dynamics associated with historical versus recent urbanization are related, they are not identical. Thus, while temporal change in Houston's urbanization is driven primarily by socioeconomic status, the social dynamics associated with spatial disparities in urbanization relate primarily to race, regardless of socioeconomic status. These results are noteworthy as urbanization in Houston does not fully comport with existing theoretical perspectives or with empirical findings nationally. Instead, we suggest these findings reflect the city’s politics and culture surrounding land use. Thus, beyond its important social and environmental implications, this study affirms the utility of fusing socio-demographic data with satellite remote sensing of urban growth, and highlights the value of the socioenvironmental succession framework for characterizing urbanization as a recursive process in space and time.  相似文献   

10.
Consistent with the challenges of sustainability science, land architecture offers a comprehensive approach to land system dynamics useful for numerous types of assessments, ranging from the vulnerability of coupled human–environment systems to forest transitions. With antecedents in several research communities, land architecture addresses the tradeoffs within and between the human and environmental subsystems of land systems in terms of the kind, magnitude, and pattern of land uses and covers. This approach is especially cogent for changes in tropical forests, given the broad-ranging forces acting on them and the equally broad-ranging consequences of their loss. The rudiments of the land architecture approach are illustrated for changes in seasonal tropical forests in the southern Yucatán of Mexico, the pivot of which is the Calakmul biosphere reserve. Simplifying the dynamics involved, the region-wide land architecture is the collective design of stakeholders with different land-use goals that favor tradeoffs in subsystem outcomes serving better either the reserve and related programs or the smallholder farmers that populate the region. A major tradeoff involves forest cover per se, which holds implications for forest transition theory. Evidence for an incipient transition involves the scale of analysis taken. The dynamics involved hold too much uncertainty to forecast a permanent transition to more forest cover and imply that more complex but robust versions of the theory are required.  相似文献   

11.
12.
Watershed management in an urban setting: process, scale and administration   总被引:2,自引:0,他引:2  
Efforts in post-industrial countries to refine environment and planning administration in the face of unprecedented urban growth have important implications for ecological systems and human quality of life. This paper uses the case of an urban riparian corridor in South East Queensland, Australia to contribute to understandings of interactions between land use planning processes, watershed management initiatives and broader administrative structures in urban and rapidly urbanising settings. In particular it examines the understudied application of watershed management to an urban setting. Analysis of changes to the structure and function of urban riparian corridor management over time show that changes have occurred as a result of broader policy and institutional change in three distinct phases: top-down watershed management policy (1996-2000), regional natural resource and population growth management policy (2001-2005) and the recent re-emergence of local government as the dominant actor in a multilevel networked context (2006-2008). Trends toward regional scale approaches and increased urban planning initiatives have tended to concentrate responsibilities for urban environmental management with local government. This is in contrast to most rural natural resource management experience, and highlights the importance of meta-governance frameworks in ensuring the enduring applicability of the watershed management model to urban and rapidly urbanising catchments.  相似文献   

13.
Peri-urban areas around urban agglomerations in Europe and elsewhere have been subject to agricultural and land use research for the past three decades. The manner in which farming responds to urban pressures, socio-economic changes and development opportunities has been the main focus of examination, with urban demand for rural goods and services representing a driving factor to adapt farming activities in a multifunctional way. Working within the peri-urban framework, this review pays particular attention to the relevance of multifunctional agriculture. Academic discourses and empirical insights related to farm structure and practices beyond conventional agriculture are analysed. Diversification, recreational and environmental farming, landscape management and specialisation, as well as direct marketing are all taken into consideration and discussed within the context of landscape functions. The provision of rural goods and services is contrasted with societal demands on peri-urban agriculture. This review finds that multifunctional agriculture has been commonly recognised in peri-urban areas – a phenomenon that includes a large variety of activities and diversification approaches within the context of environmental, social and economic functions of agriculture. In response to the post-productive, consumption-oriented requirements of the urban society, peri-urban farmers have intensified their uptake of multifunctional activities. Nevertheless, not all multifunctional opportunities are being fully developed when one considers the large and growing urban demand for goods and services provided by agriculture carried out near the city. This paper discusses policy and planning approaches to support multifunctional agriculture in peri-urban areas.  相似文献   

14.
Prevention and mitigation of the progressive spread of artificialization are key goals of environmental protection policies leading to the establishment of protected areas. Artificialization processes can be effectively assessed by analyzing land cover and land use changes, which put in evidence different kinds of processes that spur a decrease in natural areas and an increase in artificial ones. In this article, we first analyze land cover change processes by developing transition matrices using the simplified Land and Ecosystem Account taxonomy, and next we compare and contrast processes that take place in areas characterized by different levels of environmental protection, which we identify as follows: natural protected areas, sites of the European Natura 2000 network, and unprotected areas. We take the Italian island of Sardinia as a case study, since a system of national and regional parks and an extensive Natura 2000 network have been established in this region, and analyze and compare land cover change processes over more than twenty years (i.e. between 1990 and 2012). Our results highlight significant implications for the definition and implementation of planning policies aiming at preventing or mitigating artificialization processes within the island. However, the methodological approach here proposed can be applied in other European regional contexts so as to tailor planning policies to the local characteristics of ongoing land cover transition processes.  相似文献   

15.
Urban containment strategies are one of the best-known planning instruments for managing urban sprawl. The two main types of such strategies are greenbelts and urban growth boundaries. The boundaries set by the Land Use Plan in Switzerland have been applied since 1970. We evaluate the effect and success of this strategy by analysing expansion of developed land, change in number of buildings, and building density within and outside building zones in four Swiss municipalities 1970–2000. Our results show that the boundary restricted most development to building zones and promoted increased building density. Generally, building density increased in the building zones but decreased outside of building zones. For more efficiency and success, the political institutions should specify explicit goals for development inside and outside of building zones, and develop new instruments for guiding development outside of building zones.  相似文献   

16.
Metropolitan planning organizations (MPOs) in the United States have instituted regional strategies to encourage development around mixed use, higher density urban centers in response to air quality and transportation challenges. Because MPOs lack regulatory authority, these organizations have relied on voluntary approaches to coordinate regional planning for land use and transportation. While scholars have examined voluntary regional planning, there have been few studies of the urban centers concept. In Denver, Colorado, the MPO’s Metro Vision plan promotes local adoption of centers supported through incentives. In this study, we examine whether existing conditions and future plans for centers support regional goals. Our approach relies on interviews and spatial data to categorize centers and evaluates whether each type of center is likely to achieve regional goals for transit, design, density, diversity, and destination. This work generated a typology of five center types: historic town centers, greenfield, industrial, commercial, and suburban mixed use. We find that the adopted centers fall short of meeting regional goals under existing conditions, but future plans for center types show promise. This typology offers more refined strategies and targeted incentives for other metropolitan regions considering a centers policy to support regional goals. There is also a need for better regional monitoring and improved indicators to assess progress.  相似文献   

17.
18.
Collaborative planning processes have been criticized for inefficiency, but attempts to improve them in planning of urban nature have been limited by lack of usable evaluation methodologies. This paper presents a framework for evaluating and designing collaborative processes in strategic planning of land use and nature areas. A framework with four key perspectives and their success criteria was developed with the help of literature and data from interviews and focus groups in two case areas in the Helsinki metropolitan area, Finland. Planning organizations can use the framework as a tool and source of inspiration in designing collaborative processes and their evaluation, and in shifting their practices towards the organizations’ own specified goals. A conscious design of more efficient and holistic collaborative planning can be achieved with case-specific operationalizing of this framework.  相似文献   

19.
This paper develops an integrated economic, hydrologic and GIS modeling framework to examine the cost-effective targeting of land retirement for establishing riparian buffers in agricultural watersheds. Previous studies have examined the efficiency of targeting large land parcels for retirement or targeting management practices such as conservation tillage but have not considered narrow variable buffer strips. An empirical application of the framework in the Canagagigue Creek watershed in Ontario shows that average and marginal costs of sediment abatement increase at an increasing rate as the environmental goal becomes more stringent. The locations of the buffer strips vary across the watershed and are not necessarily located on those sites with greatest slope or those adjacent to visible streams. Cost effectiveness is further increased if the targeting is extended to allow for the width of the buffer strip to vary by location rather than assume a uniform width. The modeling results have important policy implications for the design of conservation stewardship programs such as setting appropriate environmental health goals based on marginal abatement costs relative to marginal benefits, and setting physical characteristics of the riparian buffers for selection along the drainage network in targeted sub-catchments.  相似文献   

20.
Land use regulation has always been regarded as one of the most crucial means of macro-control of urban growth, which can affect a city’s land values directly and further determine related urban economic well-being. Since the New Type Urbanization Strategy proposed by the government in 2014, China’s mode of urban growth has been transformed from addressing “quantity” to “quality" in the urbanization process. In this case, the regulation of land use by the Chinese government plays a more important role in urban growth. With their planned land regulatory scheme, the various instruments employed by Chinese governments have quite different mechanisms influencing land prices. However, there are no rigorous studies focusing on the land use regulation system and its impact on land values to date, particular in China. This study seeks to explore how land use regulation affects urban land values through the systematic lens. We summarize the main land use regulatory instruments based on the analysis of China’s planned land use system and urban land banking system, including the construction land quota, constraints on the allowed floor area ratio (FAR) of each land transaction parcel, and land supply restrictions. A new dataset based on land transaction data from 2007 to 2016 that covers 286 prefectural cities from the country’s coastal, central, and western regions is used in the empirical analysis. The results show that the effects of the floor area ratio (FAR) on land values are significant and positive, with the residential and commercial land supply ratio being a key factor. Moreover, the results imply that the effects of constraints on FAR and commercial land supply vary between regions. These findings indicate that the Chinese land market is considerably distorted by excessive administrative interventions by local governments, in the stage of urban transition guided, the capable regulatory instruments could play an important role in adjusting urban land prices and hence impact on urban growth.  相似文献   

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