珠江三角洲跨尺度景观特征评估及在区域空间治理的应用探索

Cross-Scale Landscape Character Assessment of the Pearl River Delta and Exploration of Application in Regional Spatial Governance

关键词:  风景园林  景观分类方法  景观特征评估  跨尺度  区域空间治理  珠江三角洲

Key words:  landscape architecture  landscape classification approach  landscape character assessment (LCA)  cross-scale  regional spatial governance  the Pearl River Delta

摘要:

将广域连续的国土景观划分为实体、可识别的景观空间单元是构建可持续的空间规划管理框架的第一步，多尺度的景观层级嵌套结构有助于适应多层级 的空间规划体系。采用参数法与整体法相结合的框架，基于中国珠江三角洲9个城市的陆域行政范围，进行宏观区域尺度和中观城市尺度的景观特征评估，尝试建 立景观特征大纲图和景观特征详细图2个层级的景观特征评估成果。以此建立对珠三角景观格局的整体认知，识别总体特征与关键特征，建立系统的景观信息基 线，为珠三角景观风貌管控提供综合性空间框架，同时基于对城乡混杂景观的分析为区域空间治理提供新的视角。

Abstract:

Dividing the extensive and continuous territorial space into physical, recognizable landscape units is the first step in constructing a sustainable spatial planning and management framework. The nested structure of landscape hierarchies at multiple scales helps to adapt to a multi-tiered spatial planning system. "Landscape character" is an integrated representation of natural, cultural, and social attributes across administrative boundaries and is a valuable tool for identifying the diversity of and changes in the landscape character of the national territory. The Pearl River Delta in China is one of the fastest urbanizing regions in the world, with a high degree of urban-rural mixing and rich natural landscapes. As a complex urban-rural landscape pattern at multiple scales, there is an urgent need to apply more holistic and integrated cross-scale tools to guide and manage comprehensive urbanization and landscape change. The research adopted a combined framework of parametric and holistic approaches to identify landscape character types and delineate areas in the Pearl River Delta region at the macro-regional and meso-urban scales. At the regional scale, a parametric method was used to overlay the elevation, land cover, and urban/ rural land use datasets to generate 17 landscape character types. Thus, it can present the holistic pattern of transforming the natural environment under the influence of human behavior. At the urban scale, 51 landscape character types are defined based on satellite image maps using a holistic approach while considering factors such as land use, building layout, and agricultural patterns. Thus, it is possible to present subtle differences in the impact of human behavior on different landscape characteristics in urban/rural areas. There is a nested structure and progressive relationship between the two scales, with the regionalscale classification presenting the overall structural characteristics and the urban-scale classification supporting the detailed information. Through the multiscale perspective, understand and describe the landscape in the urbanization process, identify the overall characteristics and critical characteristics, and establish a holistic perception of the landscape pattern of the Pearl River Delta. The overall landscape structure of the Pearl River Delta can be summarized as being surrounded by mountains to the east, west, and north, and to the sea to the south, constituting the estuarine delta plain with the confluence of the three rivers. The urban landscape is located in the plain area, in which the mixed urban-rural landscape spreads outward in disorder and occupies nearly 4/5 of the urban landscape. It presents a unique landscape with mixed factories, villages, and farmlands. The results also construct a systematic landscape baseline that can provide a nested spatial framework to assist urban and rural spatial governance, landscape conservation, and management in China. Mixed urban-rural landscapes are essential to spatial governance in the Pearl River Delta region. The governance of mixed urban-rural landscapes based on the landscape character assessment of the Pearl River Delta can validate its potential as a comprehensive spatial framework. From a macroscopic perspective, the research focuses on the mixed landscapes of urban-rural boundaries, considering their spatial location and dominant functional attributes, and clarifying the governance tasks and transformation objectives. The landscape development strategy map of the Pearl River Delta, finally formed, has a clear structure and can provide corresponding planning and management strategies for different types of landscapes.