基于“双评价”与FLUS-UGB的城镇开发边界划定——以长春市为例

运用系统性思维，在综合考虑国土空间全要素、协调空间规划各阶段的前提下，结合资源环境承载能力评价、国土空间开发适宜性评价（“双评价”）与FLUS-UGB模型，提出了城镇开发边界划定的系统流程，包括基于“双评价”识别本底特征、基于功能遴选划分功能适宜区和基于FLUS-UGB模型划定边界3个步骤。以长春市为例，基于2010-2015年土地利用数据进行模型模拟与精度验证，总体精度为0.922 3，Kappa系数为0.844 6，表明模型具有较高精度，进而模拟了2035年长春市城镇发展形态，划定了城镇开发边界，并制定了切实有效的管控手段。这套划定方法以科学评价识别前端本底，以协同共生整合中端功能，以有机生长优化末端布局，为长春市国土空间开发与保护格局的确立迈出了稳健的一步。

Delimitation of Urban Development Boundaries Using Two Basic Evaluations and FLUS-UGB: A Case Study of Changchun

The reform of the ecological civilization system and mechanism has provided a background upon which the “three lines” delineation acts as an important avenue for optimizing land organization and natural resource management. The urban development boundary-as the rigid bottom line for controlling town land use and expansion-is essential to the forced transformation of the city and the improvement of urban governance and governance capabilities. However, most existing methods of setting urban development boundaries emphasizes the urban factors alone or simply coordinates the urban development boundary with ecological and agricultural elements; they rarely examine urban development boundaries from the perspective of global pattern optimization, thus causing many issues to align with pre-technical, post-management management. Additionally, after the 18th National Congress, China entered a new governance stage that identifies problems using systematic problem solving and has gradually implemented this problem-solving framework. Therefore, the study of urban development boundaries should be reformed from a direct or partial perspective to a comprehensive perspective. By adopting systematic thinking, this study considers all elements of national land space and the coordination of various stages of spatial planning and then presents a systematic method with which urban development boundaries may be delineated, including two basic evaluations, three types of space division, and urban development boundary delimitation. Specifically, the section on the two basic evaluations identifies environment backgrounds by overlapping assessment. With the resource and environment carrying capacity evaluation, the resource endowment level and carrying capacity constraints can be identified by rating and summarizing major natural elements. And with the space development suitability evaluation, under three different developing orientation, the suitability level of ecological, agricultural and urban functions can be determined by rating and summarizing both natural and human factors. The section exploring three types of space division emphasizes land use type determination, the process by which authorities select the most suitable land designation based on the space development suitability evaluation result and functional development priorities, thus extracting urban development space. The urban development boundary delimitation section includes the FLUS-UGB model, which utilizes the random forest model to select input factors; the cellular automata model to simulate city dynamic evolution; and policy and planning factors that revise spatial growth trends and delimitate boundaries morphologically. This study presents Changchun City as an example, using land use data from 2010 to 2015 to perform model simulation and accuracy verification with an overall accuracy score of 0.922 3 and Kappa of 0.844 6, which indicates that this model is highly accurate. We then use this model to delimitate the urban development boundary of Changchun City in 2035 and formulate effective control measures. This method progresses from background values to suitable target values and control values, recognizing natural endowments and integrating function and optimize layout. Thus, it comprises a complete urban development boundary delimitation framework, which works toward establishing development and protection patterns of land space in Changchun City and provides a reference for further domestic research.