Measuring urban sprawl using land use data

Digital land use data, generally derived by remote sensing operations, have become widely available for even the most remote areas of the globe. Here we investigate how to use land use data to measure three of the most characteristic aspects of urban sprawl: low density, low continuity of land use type (scatteredness), and low compactness of the shape of the city. For each of these categories we present multiple urban sprawl indicators. Some of these indicators have been used in the literature before, others we developed ourselves. For density measurements we illustrate how simple changes to common density indicators can improve their meaningfulness. With respect to scatteredness we show that the interpretation of entropy measures can be ambiguous. A variant on Moran’s I index does a better job at measuring scatteredness than entropy metrics. A problem that has not yet been discussed in the literature is that the grid structure of land use data can inflate the boundary of the measured area. This is particularly a problem when measuring urban compactness. We introduce new compactness indices that correct for this problem. To illustrate the discussed indices, we apply them to Graz, the second largest city in Austria, using data from the CORINE Land Cover (CLC) Project (European Environment Agency, 2010).     

The potential effect of national growth-management policy on urban sprawl and the depletion of open spaces and farmland

The debate over the effectiveness of growth-management policies reinforces the importance of empirical studies in this field, which has become not just relevant but also crucial to many places. Israel, through its spatial national-level planning, experienced especially during the 1990s, presents an empirical example that may be used to address a complementary strategy to the one that is most commonly used, as this paper suggests. This strategy is based on an examination of the future potential impact of growth-management tools proposed by national plans on the depletion of open space and farmland versus the consequences expected from the continuation of current trends. Accordingly an appropriate methodology is introduced for implementing this strategy.     

Sharing property value losses: The spatial concentration of development rights as a way to limit urban sprawl

The examination of the literature on land value capturing and compensation shows that strategies based on the sharing of value losses deserve increased attention. This topic is relevant also with regards to the Swiss context of the study: following the entry into force of more stringent antisprawl provisions at the federal level, numerous peripheral municipalities must reduce the size of the designated building zones and withdraw development rights from landowners. Two municipal cases are presented: the first illustrates the difficulties currently faced by Swiss municipal authorities; the second shows a possible way of dealing with these difficulties. In this second case, a specific instrument that allows for the sharing of property value losses was implemented in the past. This instrument, which we will call the spatial concentration of development rights, is analyzed along with the conditions that made possible its successful implementation. The political and technical transferability of this instrument outside its original context is also addressed. The results show that the sharing of property value losses helps to deal with equity issues while being less demanding in terms of institutional change compared to the creation of a TDR system in Switzerland. Thus, the sharing of property value losses deserves being discussed as a suitable approach while implementing antisprawl policies in peripheral areas.     

A Ghanaian twist to urban sprawl

With its inception in urban studies in the 1930s, the notion of urban sprawl was institutionalised and globalised. However, urban sprawl research has mostly focused on developed countries compared with the situation in African countries. To address part of this gap, this paper appraises urban sprawl in Ghana, using Ejisu a peri-urban area of Kumasi as a case study in order to understand its characteristics, causes and effects on urbanites and urban functionality. Household and physical surveys, agency interviews and document reviews were used. Findings indicate that urban sprawl in Ejisu has spatial and aspatial characteristics, and is occurring in the absence of basic infrastructure services such as water and sanitation, and has become an extra yoke on urban planning agencies who are already faced with limited personnel and logistical capacity.     

Measuring urban sprawl and exploring the role planning plays: A shanghai case study

Measuring the degree of urban sprawl largely depends on the local context and available data. This research establishes a multidimensional index which combines city expansion, urban compactness and urban form to measure sprawl. Urban planning, as part of the state-led growth approach, has exerted dramatic impact on city growth in China. Recent studies have discussed the role of planning in city growth. However, measuring the impact of planning on sprawl, has not been conducted. Taking Shanghai as a case study, this paper builds a multidimensional index to measure the spatio-temporal characteristics of urban sprawl in Shanghai from 1990 to 2010. It finds that urban sprawl was more serious in 2000s than in the 1990s, and the sprawl also presents spatial heterogeneity within different areas of the city. While quantifying the role of planning in urban sprawl, this study adopts the Geo-Detector based on spatial variation analysis of the geographical strata in order to assess the impact of planning on urban sprawl. It finds that planning is strongly correlated with urban sprawl, in other words, urban sprawl is kind of a "planned sprawl" in Shanghai. The research concludes with future planning policies necessary for a more sustainable and compact development pattern.     

How do centrality,population growth and urban sprawl impact farmland conversion in Norway?

A strong link has been observed between urbanization processes and conversions of farmland to built-up land. Most previous research has addressed such conversion of farmland in relation to the expansion of larger cities. However, broader analysis of both rural and central areas is needed to increase the empirical basis for these claims. Based on GIS analysis of farmland conversions, this paper aims to expand our understanding of how urban sprawl affects conversion of farmland. We find that most farmland in Norway is converted to built-up areas in relation to existing urban settlement areas. In line with population growth, urban areas in the most central municipalities experience the most significant urban sprawl and loss of farmland. Moreover, the remaining farmland is located in the same areas that already have converted the most. These areas also experience significant pressure for continued land take. Assuming current trends continue, future urban sprawl will pose great challenges for the preservation of farmland in land-use planning. New research and policies are required to handle these challenges more effectively.     

Assessing economic instruments to steer urban residential sprawl,using a hedonic pricing simulation modelling approach

Over the past centuries, cities have undergone major transformations that led to global urbanization. One of the phenomena emerging from urbanization is urban sprawl, defined as the uncontrolled spread of cities into undeveloped areas. The decrease in housing prices and commuting costs as well as the failure to internalize the real costs associated with natural land, led to households moving-out into the urban fringe – resulting in fragmented, low-density residential development patterns that has multiple negative impacts. Awareness for this problem has fed the need for the implementation of effective policies against urban residential sprawl – a subject that has received considerable attention in literature, albeit little attention has been given to economic incentive instruments. Hence, the objective of this paper is to assess the effectiveness of different economic instruments in steering urban residential sprawl – assessing property taxes, land taxes and public transport subsidies. To this end, the Sustainable Urbanizing Landscape Development (SULD) model is used and adapted, and a case study is provided for the medium-sized City of Aveiro in central Portugal. Results show that a flat property tax and a public transport subsidy for low and middle-income households are the most efficient instruments, leading to a decrease in urban residential area, living space and housing quantity as well as an increase in real estate values. On the other hand, a land tax results in insignificant changes in urban residential development patterns.     

Searching for farmland preservation markets: Evidence from the Southeastern U.S.

Farmland preservation is a topic of much discussion in many areas of the United States, but of little action. Only 1.6 million acres of U.S. farmland are permanently protected nationwide, a number not too different from some estimates of annual losses of farmland to development. While a number of studies have estimated the non-market benefits of preserved farmland (cf. Wichelns, D., Kline, J.D., 1993. The impact of parcel characteristics on the cost of development rights. Agricultural and Resource Economics Review 22 (October) 150–158), this study is the first to focus on the potential for a market for farmland preservation. Using primary data collected from farmers and citizens specifically to address this issue, we estimate the supply of and demand for farmland for preservation. Separate models are estimated for both privately and publicly run preservation programs. Demand is estimated under private-voluntary, public-voluntary, and public-mandatory scenarios. The results show that both public and private programs can be successful. The market capable of preserving the most acres is a tax-funded, state-run program which could permanently preserve over 200,000 acres in 5 years.     

Measuring the effect of farmland preservation on farm profitability

Purchase of development rights (PDR) programs have been created in 27 states to preserve farmland resources. These programs seek to advance several societal objectives, including the protection of farmland from development, retention of rural amenities, and promotion of the economic viability of farming. Using New Jersey farm-level data, this study evaluates whether participation in a state PDR program improves farm profitability. The propensity score matching method is used to correct for selection bias arising from the voluntary nature of these programs. No statistically significant profit differential is found between preserved and observationally equivalent unpreserved farms in our full sample of 4029 farms. When the analysis is replicated across different farm types, we find weak evidence that the profitability of preserved residential lifestyle/retirement farms is lower than that observed for their unpreserved equivalents. In contrast, we find that small farms (<$100,000 in annual sales) operated by individuals for whom farming is a principal occupation earn $414 to $436 more per acre in profit than their observationally equivalent unpreserved counterparts.     

Identifying the internal structure evolution of urban built-up land sprawl (UBLS) from a composite structure perspective: A case study of the Beijing metropolitan area,China

Differences in the internal composite structure during urban built-up land sprawl (UBLS) will generate different effects, and thus, a city’s spatial structure has important bearings on urban sustainability. This study investigates the spatial and temporal characteristics of the internal structure and allocation relationship of UBLS using multivariate spatial correlation and the Weaver-Tomas composite coefficient based on site data of granted built-up land parcels. Moreover, the composite structure evolution process of UBLS and its driving mechanism are examined in this study. The results reveal that the amount structure of the three types of UBLS (i.e. industrial land sprawl, residential land sprawl and commercial land sprawl) tended to be balanced during the study period. Following the transformation and upgrade of the urban industry structure, the overall composite structure of UBLS ranged from single residential land-use structure (Res.) to industrial-residential land-use structure (Ind.-Res.) In the early period of land marketization, the marketization land granting mechanism caused low spatial correlation between the various types of UBLS and a single composite structure, i.e. Res., single commercial land-use structure (Com.), and residential-commercial land-use structure (Res.-Com.). Subsequently, a dual-driving force including the market economy and government interventions caused a relatively high degree of spatial correlation and a multiple composite structure, i.e. Ind.-Res. and industrial-residential-commercial land-use structure (Ind.-Res.-Com.). However, the evolution characteristics of the composite structure in various regions illustrate some problems, such as the spatial isomorphism phenomenon of the composite structure and the dislocation of urban built-up land allocation. The urban internal built-up land spatial layout pattern is the embodiment of two dominant driving forces, the market and the government, interacting with each other according to natural and socioeconomic conditions. Therefore, we suggest that it is necessary to reform the future urban built-up land granting mechanism based on market guidance, and the composite structure of UBLS should be adjusted according to the regional function. The government should reinforce the macro-control of land-use planning for the dispersed granted land parcels so as to optimize the urban land-use structure.     

Urban expansion in 30 megacities of China: categorizing the driving force profiles to inform the urbanization policy

Currently, land use policy makers in developing countries face the challenge to control urban expansion in a rational and sustainable manner. In this context, understanding the urban expansion process and its determinants is essential for designing land use planning and governance strategies. This paper presents a methodological framework based on data mining techniques for exploring the determinants of urban expansion. We employ the Random Forest regression to apportion the relative importance for 33 determinants of urban expansion across 30 megacities in China. Analysis is facilitated by a dataset of urban land information in period 1993–2012 (derived from time-series nighttime light imageries) as the independent variable, and an equivalent dataset of 33 determinants of four categories (economic, demographic, social and natural) as exploratory variables. Results show that the relative importance of determinants varies with cities but shows some similarities. Greatest contribution is observed for the economic determinants, followed by social determinants. Demographic and natural determinants have comparative relative importance. In general, economic, social, and demographic determinants have increasing contribution to urban expansion, but the natural determinants show declining influence on urban expansion with time. Four clusters are identified by a Self-Organizing Map among the 30 megacities, with respect to the driving forces profiles. Urban expansion in these four clusters is respectively dominated by demographic, social, natural, and economic determinants. Based on these profiles, the land use planners can revised the original ‘top-down’ land-driven development model and formulate more locality-oriented measures to control urban expansion in an orderly manner.     

Public policy change and its impact on urban expansion: An evaluation of 265 cities in China

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.     

Impacts of fragmentation and neighbor influences on farmland conversion: A case study of the Edmonton-Calgary Corridor,Canada

Under heavy development pressure, farmland is rapidly being converted to non-agricultural uses such as houses, roads, and industrial uses. A great deal of research has investigated these farmland losses and their associated drivers. However, the existing empirical studies have neglected two important issues related to farmland conversion: spillover effects from neighboring areas and the impacts of farmland fragmentation. This study incorporates fragmentation and neighboring impacts into the farmland conversion analysis and provides new insights for the land-use/cover change literature. Empirical results indicate that increases in fragmentation further encourage farmland conversion to urban uses, but the effects are not linear with decreasing marginal influences. Land-use activities and decisions have strong spillover effects on neighboring areas. Ignoring this externality could result in biased estimates and marginal effects and thus misleading policy decisions and recommendations.     

Application of spatial resource data to assist in farmland valuation

A land transaction is generally not a recurring action for most buyers and sellers, their experience and knowledge are limited, for this reason the services of property agents and valuers are sometimes used, just to get more information available. The condition of insufficient information and the inability to observe differences in land productivity gives rise to the undervaluation of good land and overvaluation of poor land. The advent of the Internet made access to comprehensive information sources easier for property agents and valuers whose critical time and resources can now be effectively managed through Geographic Information System (GIS) integrated workflow processes. This study aims to develop the blueprint for a farm valuation support system (FVSS) that assists valuers in their application of the comparable sales method by enabling them to do the following: (1) Rapid identification of the location of the subject property and transaction properties on an electronic map. (2) Comparison of the subject property with the transaction properties in terms of value contributing attributes that can be expressed in a spatial format, mainly (a) location and (b) land resource quality factors not considered in existing valuation systems that primarily focus on residential property. An algorithm, that generates an index value, was developed to allow easy comparison of the land of a subject property and that of transaction properties. This index value distinguishes the proposed FVSS from other existing property valuation systems and can therefore be used by valuers as a first approximation of a property's soil suitability, before doing further field work. The FVSS was successfully developed and tested, primarily using data obtained in the Western Cape, South Africa.     

Climate protection and compact urban structures in spatial planning and local construction plans in Germany

The paper discusses opportunities for integration of the climate protection strategy declared by the German government into spatial and urban land-use plans in Germany.     

Urban lake spatial openness and relationship with neighboring land prices: Exploratory geovisual analytics for essential policy insights

Possessing ecological service functions, as well as social and economic values, urban lakes are an important part of urban open spaces. The improvement in the openness of urban lakes is crucial to enhancing the efficiency and fairness of urban land use. Accompanied by China's rapid urbanization, China's urban land prices continue to rise and the government relies on land finance. Meanwhile, the number of urban lakes is decreasing, the lake water surface area is shrinking, and water pollution is becoming more serious. By using exploratory indicators, this study quantifies the degree of openness of urban lakes, and focuses on the relationship between lake spatial openness and neighboring land prices. Taking Wuhan (China) as a study case, we proposed a conceptual framework to guide the analysis within the context of land use policy. Then, we created exploratory indicators to quantify the spatial openness of urban lakes and mapped the results. Afterward, we conducted an exploratory geovisual analytics of urban land prices and lake spatial openness. Finally, we used a regression model to examine the relationship between prices and openness. Our results show that our new indicators were able to reflect the openness of the lakes in the central urban area of Wuhan simply and effectively. The overall spatial openness is relatively high, the mean values of two main indicators reflecting the openness percentage of the lakes are 69.91 % and 67.57 % respectively. However, there are still obvious regional differences between the openness indicators. The relationship between openness and neighboring land prices is spatially heterogeneous. Based on our analysis, we finally propose policy suggestions for protecting urban lakes and rational land use in the rapid urban expansion occurring in developing countries.     

Using photo-surveys to inform participatory urban planning processes: Lessons from practice

Photography based methods have been under-utilised as a participatory tool to inform urban planning and decision making processes on citizens’ concerns, although they present several potential advantages in terms of facilitating communication on complex aspects to decision-makers. In this paper we explore the potentialities and limitations of Photo-Surveys (PS) for this purpose drawing upon the case of Thornbury, a small town in the Southwest of England. We organised a PS exercise where participants were asked to take photos on positive and negative aspects of their town. Participants were then interviewed to discuss their photos.PS allowed obtaining high amount of in-depth information with a lower number of participants than other methods, helping to build an improved understanding of some of the issues identified. Some of the PS criticisms found in the literature such as reliability and objectivity in the interpretation of results (photos) and depth of the information gathered could be demystified. One of the main findings was that aspects that could be deemed as of difficult visual representation (e.g., feelings, past events, abstract aspects) were present in the photos.Given the low number of participants, views gathered cannot be seen as representative, but they provide interesting insights about living in Thornbury and support reflection upon the use of the method. PS also worked as an entry point to some of Thornbury's social networks, allowing the authors to get acquainted with the community, thus paving the ground for further participatory work. However, there some issues regarding anonymity that will need to be dealt with.PS asks for little knowledge on the town and on the main issues affecting the population, and therefore, can be useful for developing surveys and questionnaires, as a tool for participatory rural appraisal or participatory active research. It can also be used for gathering views in the early stages of the evaluation of plans and projects, explore an issue more in deep including an array of stakeholder perspectives on the matter.     

Impact of an urban growth boundary across the entire house price spectrum: The two-stage quantile spatial regression approach

This study provides evidence for the impact of an urban growth boundary (UGB) on house prices. The study employs a two-stage quantile spatial regression method on a dataset that inventories sales transactions of single-family houses within two miles of either side of the eastern boundary of the primary UGB in King County, Washington. The results show that while the UGB decreases house prices across the entire house price spectrum, the impact is uneven; it is most pronounced for houses in the 5th to 8th decile of prices. These findings should encourage policy makers to adopt sub-housing-market-level policy approaches to address UGB and other urban and regional development policies’ potential impacts on house prices.     

Urban sprawl and climate change: A statistical exploration of cause and effect,with policy options for the EU

This study provides a brief evaluation of the relationship between trends in transport emissions and urban land-use by analysing correlation between transport CO₂ emissions data, GDP and population data with land-use change data from the CORINE database for EU Member States between 1990 and 2000.     

Environmental policy integration: Towards a communicative approach in integrating nature conservation and urban planning in Bulgaria

As urban areas continue to expand, the need to consider nature conservation objectives in planning is growing. Policy makers across Europe recognize that effective nature conservation requires an integrated approach to land use planning that includes relevant ecological and spatial knowledge. Although a number of such integrated approaches have been developed, many local authorities in Europe encounter important institutional barriers to this integration. This is particularly true for countries in Central and Eastern Europe (CEE) like Bulgaria. The post-socialist transformation in Bulgaria led to intensified urban growth and local authorities struggle to find a balance between environmental and socio-economic interests. Meanwhile, the Environmental Policy Integration ‘principle’ (EPI) has been gaining prominence in Europe, aiming to address the trade-offs between environmental and economic incentives. Research highlights that successful EPI depends on institutional processes within different economic sectors and across governmental scales. These processes have not yet been comprehensively studied in the CEE and in Bulgaria. This article assesses the EPI process in urban planning in Bulgaria and identifies the institutional approaches that may contribute best to EPI in urban planning. Using the example of the “Corner Land” project in the city of Burgas, we discuss the key challenges that the local authorities face in addressing nature conservation in land use plans. The findings indicate that EPI is to a high degree constrained by the lack of an efficient communicative process across fragmented organizational structures throughout the entire planning process. While a procedural approach to EPI appears to be prevalent it is concluded that a communicative approach is urgently needed if the sustainability of urban plans is to be safeguarded and negative impacts on nature prevented.