Objective The theoretical exploration of contemporary Chinese landscape architecture has always been a concern of the landscape architecture discipline. However, due to the difficulties in the modern transformation of cultural traditions, the problems in integrating Western theories, and the mismatch between professional practice and conceptual expression or value judgment, the systematic theoretical construction of Chinese landscape architecture still needs further refinement. From a systematic perspective, this research comprehensively reviews and evaluates the content and development of theoretical research on Chinese landscape architecture since the 1980s, in order to provide reference for further systematic theoretical construction and promote the development of disciplinary theories, methods and technologies.

Methods Through literature research, this research analyzes representative theoretical writings on Chinese landscape architecture since the 1980s. It summarizes, compares and reflects on the ways, ideas and methods of constructing the theoretical system of landscape architecture, and explores different approaches to understanding the theory and practice of landscape architecture. At the same time, this research chronologically explores the diachrony of viewpoints and understanding of the construction of theoretical system, and through comparative research, probes into the synchrony of characteristics, similarities, differences and correlations between different perspectives of construction.

Results This research identifies and analyzes the similarities, differences and correlations between five theoretical systems, namely the traditional, design, space, knowledge and discipline systems. The exploration of the traditional system starts from The Craft of Gardens (Yuan Ye), a classical monograph on gardening. Meng Zhaozhen’s Yuan Yan inherits and develops the traditional gardening philosophy, while other scholars strive to explore the potential of tradition through more discovery of classical literature. There may be two ways for further exploration of tradition: One is to search inward to identify traditional elements through adherence to self-worth concepts; the other is to explore outward to review and transform tradition from a modern perspective, with the in-depth understanding of differences as a means of bridging. In terms of the research on the design system, Sun Xiaoxiang proposed in the 1980s a system consisting of three design processes and methods, namely habitat, picturesque scene and artistic conception. Meng Zhaozhen put forward a design sequence with Chinese characteristics: clear intention, conception, location, naming, layout, micro management, lingering charm, and sealing. In the new millennium, Zhu Yufan proposed a theory of juxtaposition, transposition and mediation titled three-position theory (“Sanzhilun”) to address the issue of inheriting material culture in contemporary landscape design. Ding Shaogang attempted to construct an “open theoretical system” by exploring the essence of traditional Chinese “imagery” aesthetics. In view of the various design theories above, the theory of “Research through Design” may help organize them into an “orderly” system, thus further guiding the development of the theory and practice of landscape architecture. In terms of the research on the space system, Wang Juyuan put forward a research and practical system consisting of the three major parts of traditional gardening, urban greening, and landscape planning, which was influential in the 1980s that reflected the basic thinking on the different spatial scales covered by the research and practice of landscape architecture. Following this, subsequent scholars expanded and updated the space system. For example, Sun Xiaoxiang summarized the central disciplinary work as gardening art, urban environmental green biological system engineering, and earthscape planning, and Meng Zhaozhen proposed the three levels of gardens and scenic spots, urban green space system planning, and landscape planning, etc. The construction of a theoretical framework based on the division of “spatial scales” seems to have reached a consensus in the expression of rational cognition and logical thinking. In terms of the research on the body of knowledge, different understandings of disciplinary characteristics correspond to different definitions of systems. Sun Xiaoxiang proposed that landscape architecture is a comprehensive discipline that mainly focuses on “biology and ecology”, and further defined the four basic knowledge categories of natural science, biological science, agricultural application science, and comprehensive green biological system engineering. Jin Boling regards “art” as the fundamental of landscape architecture, and constructs the four core categories of knowledge related to artistic creation, plants, garden history and culture, and techniques of landscape construction. Liu Binyi considers the most vital core of the discipline as theory and practice at the three aspects of environmental ecology, behavioral activity, and spatial form, and further defined relevant knowledge into six aspects: “background” and “society”, “activity” and “thought”, and “construction” and “imagery”. Taking “Jing” as the “hard core”, and “Jing-Qi-Di” and “Di-Jing” as the core categories of the discipline, Yang Rui established eight basic categories of thoughts, values, principles, techniques, functions, mechanisms, images and meanings. Based on different understandings of the “core” of landscape architecture, the construction of the landscape architecture body of knowledge demonstrates the multifaceted understanding and possible comprehension of landscape architecture from multiple dimensions and directions. The research on the discipline system also relies on the understanding of the core of the discipline. Li Min pointed out that the key to the essence of landscape architecture is the “recreational living environment”, and put forward the three major fields of landscape science, landscape construction, and landscape management. With reference to the experience of relevant disciplines, Lin Guangsi proposed the three secondary disciplines of history, theory and criticism of landscape architecture, landscape planning and design, and landscape plant resources and applications. Agreeing on the opinion of centering on landscape planning and design, Wang Shaozeng established the four secondary disciplines of planning and design, construction and management, ornamental plants, and human settlement environment theory. About ten years later, based on the exploration of the concept of “Jing”, Wang Shaozeng further proposed to name the discipline as “Yingjingxue” and divided the discipline into five sub-categories: scenicology, urban-rural habitats, environmental art, tourist places, and habitat restoration. The various branch disciplines and working contents exhibit similarities and differences, which, however, may not play a role in clarifying the core of the discipline with the continuous expansion of its theoretical system, thus leading to a dilemma of attending to trifles and neglecting the essentials.

Conclusion The theoretical system of landscape architecture integrates different elements through the inheritance of traditions, the consolidation of design approaches, the division of spatial scales, and the synthesis of disciplinary knowledge, manifested as the “relationship” between elements and systems. At the same time, with the rapid growth of disciplinary knowledge, the concepts of “core” have created opportunities for creating connections between elements at different levels with respect to “differences” or “similarities”. In addition, the relationship between system and context of the ancient and modern times, and of China and Western countries, determines the basic positioning, and dynamic development of the theoretical system of landscape architecture. Such system is not deterministic or static, and its role may lie more in the improvement of basic knowledge or the transformation of thinking patterns, thereby creating open answers for solving different problems in a composite way of perceiving the world.