Abstract
Facing the need to control urban sprawl, many Chinese cities are exploring the use of development-limiting boundaries, such as urban growth boundary (UGB) and urban development boundary (UDB), as required by the central government. Through a key word search of several databases including Web of Science and China National Knowledge Infrastructure, we identified and reviewed hundreds of articles published in academic or professional journals. Our review shows that policy processes discussed in the literature have emphasized the technical aspect with analytical sophistication. We identified three types of approach to UGB and UDB in the literature: the growth-driven, the constraint-oriented, and the hybrid. While urban theories and modeling techniques that originated from Western countries have greatly influenced the analytical process underlying some of these approaches, the UGB/UDB policy debate and explorations were also responsive to China’s unique urban and policy conditions. Despite the rich empirical content in the literature, very little research has been grounded in a scientific understanding of China’s urban development. Issues such as intergovernmental coordination, policy enforcement, and evaluation were also inadequately addressed in the existing literature. The literature’s newness may have been a major factor for these limitations. Our critique of the current literature may inspire new areas of research to generate knowledge that can inform China’s continuous policy efforts to combat urban sprawl.
Introduction
China’s rapid urban expansion in the past two decades has exhibited patterns characteristic of urban sprawl with significant environmental costs. Among the many strategies explored by Chinese governments to guide urban development and fight sprawl is the use of development-limiting boundaries to contain urban expansion. These lines or boundaries take various names in local planning, such as urban growth boundaries (UGBs), urban development boundaries (UDBs), or urban construction boundaries (UCBs). Like their counterparts employed in developed countries, such as the United States and Australia, these policy tools’ theoretical justifications, proper implementation methods, and ultimate effectiveness are still at the center of debate among scholars, practitioners, and policy makers.
In this article, we review current literature on the use of these development-limiting lines/boundaries in urban China. The literature covered in this review includes scholarship written in Chinese or English identified from extensive searches of academic journal databases as well as gray literature (e.g., government reports, technique papers) found through online search engines (e.g., Google and Baidu). This review aims to follow the intellectual progression and assess the importance and comprehensiveness of existing literature from a policy studies perspective. We are particularly interested in examining the utility of current literature to inform policy processes in relation to China’s desire to base policy on science and its goals underlying the pursuit of a new kind of urban growth that balances economic development and environmental protection.
The research has discovered an emerging body of literature that explicitly tackles these development-limiting boundaries. Our review suggests that, while the literature addresses various goals connected to the central government’s policy initiative, there is a tendency to rely on a technical approach to achieving those goals. The policy process discussed in the literature has emphasized the technical aspect with analytical sophistication. We identified three types of approach to UGB and UDB in the literature: the growth-driven, the constraint-oriented, and the hybrid. While urban theories and urban modeling techniques that originated from Western countries greatly influenced the analytical process underlying some of these approaches, the UGB/UDB policy debate and explorations were also responsive to China’s unique urban and policy conditions, which is manifested in the adoption of a bottom-line approach to boundary delineation and discussions about strategies to use UGBs/UDBs as a unifying apparatus to integrate existing spatial controls. Despite the rich empirical content in the literature, very little research has been grounded in a scientific understanding of China’s urban development. Issues such as intergovernmental coordination, policy enforcement, and evaluation were also inadequately addressed in the existing literature. The literature’s newness may have been a major factor for these limitations.
This article is organized in six parts. Following the Introduction, we provide a description of the context of these spatial strategies in China and the governance systems in which these policy tools have been put into experimentation. Such contextual understanding helps define the scope of this literature review as well as our research objectives and is described in the section proceeding Method. After presenting the findings, we conclude this article with a critique of the current literature and suggestions for future research.
Research Background
The urgency to adopt spatially explicit planning strategies for China’s urban management arose from the growing fear that environmental changes induced by urban development will lead to the country’s natural resource depletion and ecosystem collapse (Qian, Finamore, and Chan 2007; Yang, Yin, and Ying 2013). While many Chinese cities need continuous urban development to help realize the nation’s socioeconomic goals and maintain social and economic stability, the central government has made it clear in a series of high-profile urban work conferences and associated official documents that China can no longer afford to sacrifice its environment for economic gains, and it is essential to national security to protect areas of significant ecological value (Ma 2005).
Despite the substantial legal and policy progress China has made in its environmental management system in the past two decades (Güneralp, Perlstein, and Seto 2015), environment-oriented legislation, policies, and strategies put forward at the national level have often been poorly enforced at the city level, where short-term economic and political benefits afforded by urban development often drive local governments’ land use decisions (Ma 2005; Zhu and Tang 2018). Methods employed to control land consumption in a bid to slow the trend of excessive urban expansion have not been effective. Analyses of satellite data show that China’s developed area expanded by 78.3 percent from 1990 to 2000 and again by 85.5 percent from 2000 to 2010, compared with 28 percent and 67 percent of urban population growth for the same periods, respectively (Wang et al. 2012). In this section, we discuss the issues underlying the ineffectiveness of existing spatial controls of urban development and describe the fragmented institutional context against which the central government’s UDB initiative was launched.
Before we delve into the governance of urban land development in China, it is worth noting that China has a long history of applying various kinds of policy tools to manage and control urbanization quantity and speed in pursuit of its national social, economic, and political goals. These include population policy (e.g., the residential registration, hukou, system) to control urban population growth, infrastructure and industrial investment policy to balance urbanization distribution, economic policies to stimulate market-based urban development, and land policy to prioritize national goals via urban land governance. More recently, the central government has begun to pay more attention to the quality of urbanization by emphasizing the need to have people-oriented urbanization and urbanization that promotes ecological civilization, which led to the use of new tools such as “green GDP” as a performance measure to incentivize city leaders to adopt a more balanced urbanization approach. The development-limiting lines in the form of UGBs or UDBs are among the new policy devices considered by the central government to address the issue of urbanization quality. In this literature review study, we focus our attention on these promising yet understudied spatial planning tools aimed at controlling overall urban development patterns.
China’s land development process is managed by a top-down and command–control governance regime consisting of multiple systems of bureaucracies: the economic and social development planning system, the land use planning system, and the urban–rural planning system. Each of the systems uses a hierarchy of plans to manage urban growth and development where a national plan controls or guides plans made by lower level governments. For example, the latest National General Land Use Plan (2006–2020) strictly governs land use plans developed at provincial, municipal/prefecture, country/district, and village/town levels. These plans are instruments for the central government to incorporate national interests into local land use decisions, which has evolved from being exclusively economic driven to a more balanced consideration of economic, environmental, and social issues (China Daily, 2017). Similarly, in the urban planning system, there is a national urban system plan and a hierarchy of Urban Master Plans. The third planning system uses a hierarchy of Economic and Social Development Plans (ESDPs) to define social and economic development goals and environmental protection targets in the form of quantitative indexes and benchmarks for each level of government. 1 Consistency requirements defined by laws state that the Urban Master Plan must be in agreement with the Master land use plan, and both the land use plan and Urban Master Plan should be consistent with the ESDP at the same government level. However, no mechanism exists to ensure the consistency and conformance of these plans (Cheng et al. 2015; Zhou and Lu et al. 2017).
These plans and relevant policies have historically emphasized quantitative controls of land development and used indexes, quotas, and benchmarks as tools to manage growth (see Table 1). As the primary instrument for managing China’s planned economy, the ESDP system contains numerical targets and measures guiding various aspects of the country’s development, including the ones closely connected with urban growth: urbanization rate, basic farmland area size, urban construction area size, and so on. The land use planning system started using a quota scheme in 1987 to control annual land supply for urban development at different government levels and to ensure basic farmland is preserved at a quantity needed for maintaining China’s food security. 2 Urban Master Plans specify the amount of land needed for urban development based on projected population and economic growth. While a land use plan and an urban plan for a municipality or prefecture city often contain land use maps designating areas zoned for urban construction, no explicit boundaries are delineated in those plans to specifically contain the urban expansion prior to 2013 (Han et al. 2009). Some scholars consider the identifiable boundary lines containing all urban construction land, known as the urban construction boundary (UCB), as the de facto UGBs or UDBs in China prior to the official endorsement of such terms (see Long et al. 2013; Han et al. 2009). But there was no deliberate effort or requirement to maintain the shape of UCBs in either land use plans or Urban Master Plans, since the urban construction land areas were often determined and designated to meet quota requirements. In fact, UCBs’ physical forms were often driven by planners’ artistic/aesthetic preferences rather than an objective and scientific analysis of development trends (Long et al. 2013).
Planning Systems Managing Urban Development in China.
The local government can use various ways to rearrange the urban construction land spatially without changing the total amount of land area, including transfer of development rights between land parcels inside and outside the UCBs and even between cities and conversion of rural construction land back to farmland to allow additional farmland conversion to urban use at the city or UCB’s edge. Thus, it is not surprising that empirical analyses have shown that the urban construction land designation approach was ineffective at controlling the spatial scope of urban development (Han et al. 2009; Lai and Han 2014), although some evidence exists suggesting that it had somewhat positive effects at controlling the overall quantity of land development (Zhou and Huang et al. 2017).
Over the past two decades, the central government has started adding or strengthening spatial guidance and controls in all three planning systems, but inadequate spatial resolution, vague definitions, and lack of a mechanism to unify these tools have become barriers to their effective implementation, especially at the city level. For example, a spatial framework supporting the implementation of a National ESDP (aka the National Five Year Plan [FYP]) was proposed in 2005, and the resultant National Major Function Area Zoning was adopted in 2011 for the Twelfth FYP. This plan identifies and delineates at the national scale four primary function zones: (1) an optimization zone, (2) a key development zone, (3) a development restriction zone, and (4) a development-prohibited zone—based on a “scientific index system” that consists of three kinds of indicators: the carrying capacity of resources and environment, current development intensity, and future development potential (Fan et al. 2012). The zones provide a spatial basis to differentiate policies in a wide range of aspects including government investment, land use, environmental protection, and so on. For example, only cities within the “key development zone” can serve as national foci of future economic development if their environmental and resource capacities are considered adequate. Currently, a process is underway to create provincial-level functional plans based on the national plan. While the boundaries are explicitly demarcated on those zoning maps, the spatial resolution is often too low to allow for effective enforcement at a municipal or city level.
The land use planning system began to use a similar zonal approach to strengthening spatial control in 2009 by devising four spatial zones in a city’s land use plan based on development suitability: the permitted construction zone (developed area), conditionally permitted construction zone, restricted construction zone, and the prohibited zone (Li et al. 2017). Starting in 2008, a city’s urban plan needed to include three zones designated on the basis of land use types: prohibited construction zone, restricted construction zone, and suitable construction zone, in addition to developed/constructed zone. However, these new spatial concepts and their implementation were neither clearly defined within each of the governance systems nor well-coordinated between them (Zhang et al. 2014). A number of problems exist, including inconsistent land use classification schemes used by both planning systems, vagueness in defining the correspondence between land use classification and development suitability, lack of a mechanism to ensure policy consistency vertically and horizontally across various plans, and so on (Zhou and Lu et al. 2017). Table 1 summarizes the quantity and spatial controls adopted in the three planning systems and implemented at various government levels.
Besides the delineated zones, a number of controls with spatial consequences have also been integrated into the urban planning system for various purposes since the early 2000s. For example, green lines are delineated in an urban plan to protect green space, blue lines to protect water resources, purple lines indicate historic preservation districts, and yellow lines demarcate areas reserved for basic urban infrastructure and facilities. These spatial elements in urban plans generally do not aim to control the overall development patterns. In addition to the spatial control instruments promulgated through these planning bureaucracies, many other government agencies put forward spatial controls that can affect urban development (e.g., noise control, scenic area protection, flood control). Long, Shen, and Mao (2011) conducted an analysis of the Beijing metro area and discovered sixty kinds of concurrent spatial controls based on eighteen laws, eighty-three state and local regulations, and six international conventions.
While most of these spatial controls have seen weak enforcement, one type has received wider recognition. The national ecological redline policies mandated by the 2014 Environment Protection Law are being implemented by the environmental protection agencies at various jurisdictional levels. Under the “redline” policies, boundaries of significant valuable and vulnerable ecological lands are mapped out using the “hotspot” method to ensure its spatial precision (Yang et al. 2016). This approach has been applied to the protection of basic farmland, habitat for endangered species, critical wetland, and forestland (Bai et al. 2016). These redline boundaries have the strongest legal status compared to other spatial control tools, but their effectiveness is undermined by the fact that not all redline areas are adequately integrated into policies directly guiding urban development. Currently, only basic farmland’s redline boundaries have been precisely delineated and integrated into local land use plans at all government levels (down to the village or town level).
Institutional fragmentation and lack of a mechanism and willingness for intergovernmental collaboration is a major obstacle to policy effectiveness. The three planning systems directly managing land development are overseen by separate and independent departments: Development and Reform Commissions at various jurisdiction levels govern the economic and social development planning system, the Ministry of Land and Resources (MLR) at the central level and land use planning bureaus at local levels are in charge of the land use planning system, the Ministry of Housing and Urban-Rural Development (MHURD) at the central level and urban planning bureaus at local level manage the urban planning system. 3 The lack of coordination between these latter two governance systems has been a long-standing problem, given their diverging goals and approaches to urban development. The land use planning system bases policy decisions on concerns over land supply and constraints, whereas the urban planning system aims to accommodate land demand arising from local governments’ development ambitions. Conflicts and inconsistencies are common between urban plans and land use plans, causing confusions and loopholes in the land use decision process. These problems are further aggravated by the fact that many government agencies are often unwilling to share information and infrastructure for information management is inadequate (Long, Shen, and Mao 2011).
As a new initiative by the central government to strengthen the spatial controls in urban development, UGBs or UDBs are still at an early stage in policy implementation. While academic interest in these concepts started in the late 1990s and a few cities had experimented with similar policies at their own discretion, the emergence of UDB as a national policy can be traced to the 2013 Central Urbanization Work Conference, where national leaders proposed that UDB should be used to confine urban development into a clearly defined, geographically connected region. In the following year, MLR and MHURD identified fourteen pilot cities to explore UGB or UDB implementation. 4 Without a national standard issued from the central government stipulating the process and format of the UDB policy, local experiments moved fast and adopted a wide range of trial-and-error approaches (Lin, Qiao, and Ye 2017).
It is within this context that we examine the current literature on these spatial planning instruments and assess how intellectual inquiries of some of these issues can help inform relevant policy processes. How should these instruments be clearly defined in policy and spatial terms? How to integrate the UDBs with other spatial management tools? How can policy implementation be adequately monitored and properly evaluated? These are the questions in need of answers based on thorough analyses of cases and intellectual discourse. Additionally, one of the problems that has weakened the effectiveness of existing spatial tools is the institutional fragmentation in China’s urban development management. Regarding this issue, the central government’s UDB initiative also included a call for “Integration of Multi-Planning” of ESDP, urban and rural planning, and land use planning both at the city and county level. Such institutional reform is a huge task, and its connection with UDB brings additional complexities, as well as opportunities, in the UDB policy’s execution. The UDB itself depends on an integrative planning approach to become effective; its implementation process plays a role in coordinating and unifying the separate planning institutions. We are also interested in whether existing UDB-focused research can help inform the processes in this respect.
Research Scope and Objectives
We conduct this literature review research from a policy studies perspective (see Nagel and MacRae 1980). We focus on literature specifically addressing UGBs or UDBs in China. Our analyses draw from writings dealing with the nature, causes, and effects of these policy tools and evaluate the extent to which policy-related ideas and suggestions presented in the literature are based on an awareness of the causes behind the policy problem (in this case, urban sprawl) and an understanding of the structures and process affecting the effectiveness of policy implementation. This research has the following objectives: Develop a precise definition of these terms and identify distinctions and connections among them. We provide a review of the policy emergence and a summary of the goals and objectives associated with the planning instruments. Survey current approaches by which these spatial strategies are explored in the literature. We examine how ideas and debates presented in the literature respond to international influences and to domestic and local conditions. We are particularly interested in assessing whether proposition of a certain approach and exploration of alternatives are articulated in the literature to address issues with scientific basis, technical competency, and political process. Identify evidence presented in the literature to assess the effectiveness of these policy tools in achieving their stated goals and whether there are some unintended consequences associated with these spatial policies.
Method
We conducted a search in both English and Chinese literature. The primary targets were peer-reviewed academic writings that are analytical in nature and offer debate on the pros and cons of the policies themselves and their implementation, present various approaches to policy formulation and implementation, and discuss solutions to the challenges presented in the governance systems to the effectiveness of policy outcome. We also used descriptive writings from news reports, magazine articles, and government circulars presenting facts and accounts relevant to the policy’s definitions, goals, time line of major events recounting its evolution as well as its formulation and implementation process. This second type of literature helps contextualize our analyses and helps us assess the academic literature’s adequacy from a policy studies perspective. 5
We conducted independent searches for English literature using the following databases: Web of Science, ProQuest Social Science, ProQuest Social Science Premium Collection, JSTOR, and Google Scholar. The search for Chinese literature primarily relied on the China Academic Journals’ full-text database China National Knowledge Infrastructure. An additional search for government reports was performed using the Baidu Scholar search engine. The Web of Science Core Collection was the main database we used to search for English academic journal articles, together with other databases that supplement with records from magazines, theses/dissertations, and reports. The literature search utilized a number of terms derived from the diverse terminology used to refer to the policies in English and/or possible translations from Chinese literature. The following terms, coupled with the Boolean operation “AND ‘China’” to ensure the search outcome’s geographic relevance, were used to find records containing them in the abstract, title, and/or keywords fields. The search of Chinese literature was based on similar key words in Chinese: Urban development boundary (boundaries) Urban construction boundary Urban growth boundary (boundaries)
We screened the initial results from the term-based searches by language, document types, and publication time. We then reviewed titles and abstracts to select a subset deemed to help us answer the research questions and achieve our research objectives. Each of the articles in the final set of literature was read by at least two researchers to compare reading notes and understanding.
Findings
Literature Search Outcome
In total, we identified 27 peer-reviewed English articles published in academic journals via multiple searches. Overall, the academic literature in English on these spatial planning instruments is relatively new and shows a growing trajectory in volume. The literature spans the last decade since 2007, and 18 of the 27 articles have been published since 2016. These articles come from a variety of academic journals. The journal Sustainability has published the most articles (6), followed by Habitat International (4). The Chinese literature has a greater volume and longer history on these topics; 266 articles have been published in Chinese academic/professional journals since 1997 when the concept of UGBs was introduced (see Li 1997). There has been a rapid increase in Chinese articles on UGBs and UDBs since 2013, the year when the central government issued the call for implementing UDBs in urban planning with 203 articles being published since then. Compared with the English literature, their Chinese counterparts have been published in professional journals in urban planning and academic journals in the field of geographic research. By early 2018, a total of 42 articles have been published in the Chinese Journal Planner, 12 in City Planning Review, and 10 in Urban Planning Forum (see Table 2).
Summary of Literature by Journal Name and Year.
The nonacademic literature we included in our review mainly comes from news reports, magazines, and government reports. The value of examining this type of literature lies in obtaining information and knowledge about the time line and institutional contexts of these spatial management tools’ development. Close to a hundred records were found via ProQuest and Google search. These articles and reports come from outlets, such as China Perspectives, China Review, and AMBIO. Additionally, we used Baidu to search official web pages and documents reporting on the governments’ major announcements, statements, as well as guidelines pertaining to UDB definition and implementation.
Analysis of Literature Content
We categorized the academic literature generally into three types based on an article’s main content: institutional analyses of the structure and mechanism of bureaucratic operations supporting the UDB policy process, discussions and debate exploring methods and procedures to enable or facilitate the UDB policy implementation, and policy performance that evaluates the impacts and effectiveness of UDB cases.
The fourth type of literature that appears only in Chinese and is aimed at introducing concepts, international experiences, and case studies includes twenty-three articles, among which the practices of Portland, Oregon, appeared as the most frequently studied case (seven articles).
Most English literature pertains to policy implementation (category 2) with this category being dominated (greater than 80 percent) by articles presenting technical methodologies of policy formulation (e.g., boundary line delineation methodology). Close to 30 percent of the English literature focuses on the institutional background of targeted spatial instruments and argues for organizational reform to overcome barriers in policy processes, although very few articles address specific mechanisms for institutional change. Given the newness of these spatial tools, it is not surprising that very few articles address policy performance. Of the 49 articles we reviewed, only three articles discuss policy effectiveness. Similarly, the Chinese literature also lacks policy evaluation research. But the distribution of the first two categories is more even; 137 articles focus on discussion of policy processes and institutional support and 91 articles explore methods of boundary delineation, oftentimes with specific case studies.
Policy Definition and Objectives
Across the 27 academic articles published in English focusing on UGBs or UDBs, multiple terms, such as “urban growth boundaries,” “urban development boundaries,” “urban construction boundaries,” or even “urban sprawl boundaries,” are used to refer to the development-limiting lines wherein urban development is to be contained. The Chinese literature published in early 2000s frequently used the term “urban growth boundaries,” while most literature published since 2013 adopted the term “urban development boundaries” (126 of 203) as the concept was promoted in the official government guidelines. Our review of the literature shows that the frequency change in the use of these terms was not just influenced by the central government; it in fact reflected an evolving understanding of urban containment approaches suitable to China as the distinctions between the two terms were articulated in the discourse. After the initial screening and review of all articles’ abstracts, we conducted an in-depth reading of all 27 English articles and 50 Chinese articles. The literature content summarized below is based on the thoroughly reviewed publications.
Much of the early Chinese literature’s discussions about UGBs focused on the experiences of Oregon, United States. Portland metro’s UGB was a particularly popular case used in introducing the concept to Chinese literature in the late 1990s. The definition and understanding of this term presented in the early Chinese literature suggests an obvious Western influence. The UGB concept took on a meaning that emphasizes a boundary aimed at spatially containing projected and forecasted urban growth estimated for a targeted time (usually for the next fifteen to twenty years) and also a boundary that is expandable as time goes on. The understanding of UGB later grew to include the recognition that UGB is about not only maintaining the size and shape of the development area but also ensuring the improvement in spatial structure and relationship among various urban land uses (Zhang et al. 2014).
In the literature since the late 2000s, the definition of UDB and related research has shown an effort to adopt this tool in such a way that best meets China’s urgent needs to address environmental issues. That is, urban development should be rigidly controlled to safeguard a region’s ecological security; UDBs should serve as a bottom line against urban expansion, so that necessary regional resources and ecological environment are maintained to support the maximum level of urbanization in a region (Lin et al. 2017). Zhuang et al. (2017, 8) cited an official definition of UDBs from the Measures for Formulating City Planning published by MUHRD (2016), which states UDBs are spatial boundaries “based on the determination of factors such as topography, natural ecology, environmental capacity and basic farmland” and “areas allowing and banning urban development construction can be established, permitting the largest possible boundaries for urban construction land use.”
In more recent literature, the definition or explanation of UDB emphasized the balance between demand-driven or supply-driven approaches and has become characterized as being “flexible enough to satisfy urban development needs but rigid enough to restrict urban expansion in accordance with the comprehensive carrying capacity of the region” (Jiang et al. 2016, 1322). It tends to encompass a more comprehensive list of objectives in addition to containing urban expansion, including (1) making the UDBs a unifying instrument that integrates all existing spatial control lines, (2) compelling and facilitating coordination among various government bureaucracies, (3) requiring cities to improve the efficiency and spatial structure of land uses, and (4) balancing the energy, economic, environmental, and social impacts of urban development (Zhang et al. 2014).
Internationally, the use of development-limiting boundaries to contain urban expansion widely exists in many countries. These boundaries can take a concrete physical shape such as a deliberately created greenbelt around a city in Britain, or they can be formed as policy lines or restrictions in planning documents, such as the case of Portland metro UGB in the State of Oregon, United States. Whether those boundaries have emerged from a local jurisdiction’s own initiative or as an outcome of a higher-level government’s mandate, protecting open space and resource lands has always been a primary objective for the boundaries’ formulation and implementation. Additional objectives, such as improving efficient use of land, guiding strategic investment of urban infrastructure, and promoting compact urban form, are also closely connected to those boundaries (Abbott, Howe, and Adler 1994). Our literature review shows China’s UGBs have evolved to embrace all of the aforementioned objectives mostly because the central government is eager to emulate the effectiveness of UGB practices in other countries.
What makes China’s UGBs unique is the goal of using UGBs to delineate the maximum urbanization limit, which based on our research has not been explicitly connected with UGB practices in other countries where the UGBs typically allow for continuous although staged urban expansions. The inclusion of this specific goal reflects the Chinese central government’s determination to address the perceived existential threat from uncontrolled or poorly controlled urbanization. The policy practicality also arises from the fact that Chinese cities engaged in UGB experimentations are prefecture or regional cities with a fixed jurisdiction boundary, and a prefecture city often oversees counties, county-level cities, and townships located inside its boundary. Unlike American cities with their ability to expand their administrative boundaries by annexing in land parcels, while also being independent from each other, a prefecture city in China is in a better position to apply a regional approach to control urban expansion, to enforce intergovernmental coordination, and to strategically phase urban area expansion as the city-region’s urbanization reaches its maximum limit indicated by its UGBs.
Debate on Policy Implementations: Challenges and Solutions
The vast majority of the literature identified and reviewed in this research focuses on the mechanical aspect of the spatial policy’s implementation. More than 70 percent of the literature we reviewed introduces and discusses various methods to delineate UDBs and then applies the prescribed methods to a city. UDB delineation methodology is affected by the definition of UDB adopted in an article; thus, the literature can also be generally divided into three types: The growth-driven approach typically follows three steps: estimating future land demand, allocating the demand spatially, and then delineating the UDB. The constraint-oriented approach uses suitability analyses to identify and delineate critical ecological areas so as to protect them from urban development. The hybrid approach takes both demand and constraints into consideration. The discussions about boundary delineation methods presented in the literature exhibit intellectual progression similar to the definitions adopted in the literature for the spatial control tools.
Table 3 summarizes the methodological content presented in the literature based on the three approaches.
Summary of Urban Development Boundary (UDB)/Urban Growth Boundary Delineation Approaches Presented in Literature.
The growth-driven approach to boundary delineation typically adopts a methodology of predicting or simulating future urban development patterns based on extrapolation of historical trends. This method relies on spatial data (geographic information system, remote sensing), uses cellular automata (CA)-based technique to model the urban development process, and analyzes historical trends in land use/cover changes to determine the impacts of a number of predetermined driving factors on urban development. Such information is then used to predict urban development at a future point in time (typically year 2020 or 2030) assuming current urban trends continue. The spatial distribution of the simulated urban development is then used to help delineate UGBs or UDBs, which involves edge editing to filter out small, dispersed areas in order to form one or more enclosed, continuous polygon boundaries.
The assumption of the growth-driven approach is that growth can be accurately estimated and its spatial allocation can be precisely predicted. The confidence in this approach rests upon the capacity to fully understand urban development processes and the hypothesis that no major disruptive forces alter these processes. All technical articles presenting the simulation methods relied on urban theories originating from market-driven societies without questioning their applicability to urban China. Many conditions, such as proximity to transport infrastructure and central city location, are considered extremely important enabling factors for urban development in market-based economies. But the transport-induced urban development dynamics may not be so apparent in China as urban changes are more subject to policy and political changes (Yeh and Li 2003; Long et al. 2013). Yet, these factors are often ignored in the technical literature. Acknowledging the lack of scientific understanding of China’s urban development process, some authors suggested that the simulation techniques are better used to compare different policy scenarios’ impacts on development patterns, as opposed to delineating accurate UDBs for policy implementation (see Liang et al. 2018; Wang et al. 2017).
The constraint-oriented approach, on the other hand, considers predicting future urban development patterns as an extremely difficult if not impossible task. This approach focuses on delineation of UDBs as a means to protect the ecological system and natural resources. It often adopts “bottom-line” thinking, and the boundaries are derived by identifying necessary ecological environments to support critical ecological services, safeguard basic farmland, and ensure resource optimization; thus, the boundaries mark absolute prohibitions and restrictions to urban development. Analytical techniques used in this approach are informed by the ecological planning methodology and have been expanded by Chinese scholars in their exploration of the so-called negative approach to urban growth planning, a term chosen to distinguish the method’s emphasis on relying on ecological structure and components, not the expected urban growth patterns, to determine urban spatial management boundaries (see Yu, Li, and Han 2005). A number of studies published in Chinese have applied this method in urban ecological corridor analysis (Qiao and Yang 2013; Su, Li, and Han 2005), ecological infrastructure analysis (Yu, Wang, and Li 2011), ecological sensitivity analysis (Yang et al. 2010; Zhu, Dong, and Hu 2008), ecological security pattern analysis (Kuang et al. 2016), ecological land suitability assessment (Zhang et al. 2016; Wang 2012; Wang et al. 2013; Zhu, Mo, and Xie 2009), and so on.
The constraint-oriented approach specifically involves the use of the minimum cumulative resistance model that analyzes the impacts of various ecological and policy factors on urban development patterns by defining these factors’ resistance to urban development based on physical characteristics, locational characteristics, and policy conditions. Unlike the growth-driven approach where magnitude of impacts from various driving factors is empirically determined via statistical analyses, the constraint-based approach assigns resistance indexes to different characteristics or elements and attaches different weights (or coefficients) to the constraining factors based on expert opinion. A weighted sum of resistance scores can be computed using the indexes and weights for each spatial unit in the analysis, which results in a resistance surface. Urban expansion is likely to take place where the resistance score is minimal and can be overcome; delineation of potential urban expansion boundaries proceeds by excluding unsuitable areas and by allowing places with minimal resistance scores to develop until the development scale meets future projections (Liu and Liang et al. 2017). By adjusting the indexes and weights assigned to various aspects and factors, the authors compare UDB outcomes in multiple scenarios where the importance of different factors varies.
The third category of articles highlights the need to integrate spatial tools controlling urban development and protecting the environment into UDB delineation. Some authors suggested making additional adjustments to the final UGBs or UDBs by integrating other policy considerations and by excluding spatial control areas (e.g., redline ecological areas, restrictive development areas, farmland protection areas; B. Zheng et al. 2018; Q. Zheng et al. 2017; Zhuang et al. 2017). Others introduced analyses of an urban area’s carrying capacity, determined by the area’s natural resource capacity, environmental assimilative capacity, ecosystem services capacity, and society supporting capacity, and used the resulting capacity assessment as an added layer to make adjustment to the UGBs (e.g., excluding areas of low carrying capacity from the UGB; see Jiang et al. 2016). Similarly, some studies used the term “ecological space quality,” determined by land cover characteristics, proximity to identified threats or stressor, and degree of protection, and uses a layer showing variation in ecological space quality to refine UGBs (e.g., areas with high ecological space quality are excluded from UGBs; see Liu and Zhang et al. 2017).
An important suggestion coming out of studies in this category is to add flexibility and elasticity in the UGBs and UDBs as a necessary condition to make them practical and effective. Recognizing the inherent inability to accurately forecast future growth in both quantitative and spatial terms, some authors believe that a flexible, growth-driven UGB or UDB based on short-term development projection and a rigid UGB or UDB based on the land needed to support vital ecological services should coexist. However, there is very little scientific knowledge available to guide the decision on how much land should be allowed and where the land should be spatially located between the rigid boundary and the flexible one.
It should be noted that UGBs defined and implemented at the city region (i.e., prefecture-level city) scale, and adopting the constraint-oriented approach typically allows a city region to demarcate its maximum urbanization limit. This UGB approach often allows multiple boundaries to coexist because of the presence of multiple but unconnected urbanized areas inside a city-region’s boundary (e.g., Liu and Zhang et al. 2017). While UGBs defined in such a way make it possible to have planned urban expansion compatible with the UGB implementation, delineation of the UGBs and subsequent enforcement are susceptible to manipulation by city governments keen on seeking fiscal revenues through land development. For example, substantial urban development can be permitted or even deliberately expedited inside UGBs of secondary urban areas in the name of ensuring urban containment of the central city. Yet, from a regional perspective, such a development strategy could lead to leapfrog patterns when the new development cannot create an independent new community and instead becomes a bedroom community reliant on the central city for employment and service opportunities. Recent studies on new town development in large cities, such as Beijing and Shanghai, highlight this inherent problem (see Tan, Guy, and Li 2011; Shen and Wu 2017).
Policy Performance
The published literature suggests that currently more than thirty cities have launched policy processes implementing UDB or UGB. Some of these cities had experimented with similar spatial tools out of their own initiation prior to the central government’s directive. Figure 1 shows the cities whose UDB-related efforts have been published in the Chinese or English literature reviewed in this study. It appears cities in a wide range of geographic locations and diverse population sizes have all been engaged in UDB exploration. The work done by some of the largest cities in China, such as Beijing, Hangzhou, Shanghai, and Chongqing, has attracted a lot of attention from researchers, and each city has been the subject of case studies reported in multiple articles in either Chinese or English. However, most of the case studies published so far have been either descriptive accounts of different UDB delineation methods or debates on technological and organizational improvements considered necessary for policy implementation.
Distribution of cities implementing urban development boundary reported in literature.
Very little published research directly evaluates the performance of UDBs or UGBs, although evidence can be found in some studies indicative of the effectiveness of spatial controls similar to UDB or UGB. These studies’ efforts to identify factors affecting policy performance offer insights for speculating the success of the new tools. Han et al. (2009) and Lai and Han (2014) studied the urban construction boundaries in Beijing and found the boundaries were unable to control spatial distribution of urban development. The authors discussed several issues related to the boundaries’ failure. From a policy formulation perspective, the UCBs, adopted mainly for the purpose of quantity control of urban land, were not supported by accurate forecasts, and estimation of population growth lacked flexibility to have timely updates and adjustments. During the policy implementation process, the lack of spatial precision of UCBs mapped out in plans, inconsistent development regulation, planners’ insufficient knowledge of UCB spatiality, and inadequate monitoring of project review and construction all contributed to the policy’s ineffectiveness. To the extent that these problems may persist in the policy formulation and implementation process for UDBs or UGBs, some authors have expressed a less optimistic view of these new spatial tools’ success (Yin et al. 2017).
A few cities’ experiments with a combination of multiple spatial tools have resulted in positive outcomes. Shenzhen, for example, is one of the pioneer cities that started using various spatial instruments early on. The city delineated a UGB in 2005 and implemented strict building permit control outside the scope of the UGB. Since 2009, the city has strengthened the protection of farmland (or arable land) via several spatially explicit methods, such as excluding arable land from location selection for urban project approvals; establishing farmland protection area based on optimized and aggregated spatial distribution of farmland areas; encouraging redevelopment in the city’s built-up areas, especially areas close to the central business district; actively monitoring land use change at the urban fringes via advanced technology (e.g., remote sensing and drones); and strictly enforcing punishment for violation. The outcomes have been encouraging—from 2009 to 2014, Shenzhen city did not use up its development land quota issued by the central government; during 2013 and 2014, the city’s land development was only 20 percent of the quota. The city’s farmland area increased by almost 30 percent in 2012 and has remained stable since then (Qian et al. 2016). Another study of the city of Hefei by Huang et al. (2013) suggests that implementation of the “four-zone” spatial control in land use planning was effective at keeping new land development inside the “permitted expansion construction zone.”
Summary of Literature and Critique
In this research, we reviewed literature published in English or Chinese explicitly focusing on the new spatial control instruments UGB or UDB. These development-limiting boundaries have been promoted by the Chinese central government to contain urban expansion and balance urban development and environmental protection. Our review suggests that, while there is a dearth of evidence suggesting the policy’s impacts, most literature seems to agree that UGBs or UDBs can be effective tools for controlling urban sprawl in China based on the perceived success from experiences in the United States, especially those from the Portland, Oregon, Model (Amstrong et al. 2015). The literature shows the coexistence of different approaches to UDB. One approach applies Western-based urban theories and modeling techniques to analyze Chinese cities’ urban development trends and extrapolate spatial scope and form for future urban growth. The second approach, informed by ecological planning and in response to China’s need to deal with concerns over ecological security, adopts a bottom-line strategy that involves various ecological sensitivity- and suitability-based analytical methods to support the identification and integration of rigid UDBs for vital environmental protection and for controlling the maximum extent of urban expansion. The latest literature reported a combination of both approaches in UDB exploration. The overall existing literature strengthens the science–policy connection by informing policy-making’s analytical process, which has usually been considered weak and inadequate in China’s urban planning (Long et al. 2011).
While the set of literature under our review is rich in rigorous technical analyses supportive of policy formulation, we found it lacking in several other areas from a policy studies perspective: (1) policy implementation ideas and methods presented in much of the literature do not seem to have sufficient input from knowledge and insights gained through scientific investigations of China’s urban sprawl problem; (2) the scope of literature is limited in that important issues pertaining to a full policy process, such as policy monitoring mechanisms and evaluations, are not adequately addressed; (3) despite the increasing recognition for necessary institutional changes to facilitate coordinated intergovernmental land use decisions to make UDBs effective, formulation of realistic strategies that acknowledge political challenges is understudied in the current literature.
The literature has not adequately linked scientific understanding of China’s urban development in devising specific policy implementation strategies. This issue is apparent in the literature focusing on a growth-driven approach to UDB, which uses urban modeling technique (e.g., CA) to analyze past urbanization trends and simulate future urban growth. The validity of those simulation outcomes relies on using the appropriate and comprehensive urban growth driving factors and employing correct and consistent transition rules governing nonurban to urban land use changes. In the past five decades and as the result of major policy reforms in a number of areas, including economic planning, housing policies, urban planning, and land management, just to name a few, China’s urbanization processes and patterns have exhibited extreme dynamics shaped by exceedingly complex and ever-changing driving forces. While a growing volume of scholarship on China’s urban development helps illuminate some important factors unique to China’s urbanization, the literature on UDB does not seem to acknowledge those findings in the analyses. In other words, research on the policies aimed at containing urban sprawl in China has not adequately taken into consideration the effect these other policies has on land use dynamics.
A more fundamental issue with this history-extrapolated approach is that it basically allows past decision tendencies, which were oftentimes shaped by a growth-at-all-cost mind-set, to influence future choices. As Yeh and Li (2003) pointed out, the simulated future development may well inherit old land use problems when the historical data used to calibrate the model’s decision rules contain undesirable results or failures from the past. Since China strives for a departure from its old urbanization trends, it makes sense for the UDB tool to be formulated and designed in such a way that it manifests the impacts of new driving factors and desired decision-making rationalities, while its subsequent enforcement ensures those driving factors work.
As China continues its top-down approach to urban planning and management, the effectiveness of UDB policies also requires improvements and adjustments of many quantity controls adopted in the systems, such as quotas for urban expansion, per capita indexes for different urban land uses, and ratio indexes for different land uses (see Table 1). These quantity controls often determine the scale of urban land uses, which then defines the growth-limiting boundaries’ spatial scope. Some studies have compared the very different UDBs under different development scale scenarios (Liu et al. 2017). While several authors have alluded to the fact that some of these quantity indexes are outdated and unrealistic (Zhang et al. 2014), there seems to be a gap in the literature that fails to address the scientific basis and practical justification underlying those widely used indexes. Since one of the goals associated with the UDB policy is to improve land use efficiencies and enhance land use structure, it is necessary to include in the UDB research a reexamination of the relationship between quantity targets and UDB-determined urban forms, supported with a better understanding of those quantity controls’ impacts on urbanization efficiencies and optimization.
Some important stages in a policy process, such as policy enforcement, monitoring, and evaluation, received little attention in the existing UDB literature. This is partly due to the fact that implementation of the policies has just begun. Much evidence has been accumulated that suggests the ineffectiveness of many other spatial control tools, and investigation of the reasons has pointed to the deficiency in imposing strict punishment for noncompliance, lack of public involvement in supervision, and inadequate technology for data collection and sharing. Systematic research is urgently needed to devise a comprehensive approach to UDB enforcement and monitoring that involves strengthening its legal basis, identifying supportive policies in these areas such as taxation and infrastructure investment, and establishing intelligence infrastructure that enables open access to complete information related to urban development. Additionally, UDB policy impact studies should go beyond focusing on the boundary’s constraining effects on urbanization to include investigation on potential albeit unintended consequences, such as equity impacts on housing affordability and economic opportunities for different areas and different population groups.
Finally, the literature is also lacking critical analyses of the politics that affect every step of the policy process, an issue particularly acute in China’s multisystem urban management regime. While the literature often cites the goal of using UDB as a means to help with integrating the existing planning systems, most of the articles address this via a technological approach by exploring a process that simply combines analytical results from various land management perspectives to form one blueprint. Some authors have recognized that decisions on many of the spatial control tools may be a negotiated outcome rather than simply determined by data analyses (Bai et al. 2018). Additional research is needed on identification of different stakeholders’ preferences and on mechanisms for consensus building during the UDB policy process.
The newness of UGBs and UDBs in managing China’s urban growth has limited the amount of published scholarly work available to our research. Acknowledging the fact that the set of literature reviewed in this study is by no means exhaustive in representing the progress in and contribution to the intellectual pursuit of knowledge about spatial planning unique to China, we hope our analysis can inspire new areas of research that will generate knowledge and insights to inform China’s continuous policy efforts to combat urban sprawl.
Footnotes
Authors’ Note
The development of this article has received contributions from student research assistants at the University of Oregon and Remin University of China.
Acknowledgments
The authors would like to express appreciation to the three anonymous reviewers for their constructive comments. The authors would like to thank Jessica Morey-Collins and Roderick Hall from the University of Oregon and Lin Sun from Renmin University of China for their help with literature search and information compilation.
Declaration of Conflicting Interests
The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Funding
The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This article is supported by the Ministry of Education of People’s Republic of China project of Humanities and Social Sciences (Project No. 18YJA630141).
