Objective Industrial heritage is a kind of productive heritage. The current heritage value and landscape characteristics derived therefrom are typically determined by past production activities. With over 180 years of industrial civilization, China has a large number of industrial relics featuring rich variety, wide distribution and profound deposits. However, the identity transition from relic to heritage is often accompanied by the cessation of production activities, which accordingly results in the loss of partial heritage value and landscape characteristics derived therefrom. The main goal of landscape construction is to facilitate the sustainable rehabilitation of industrial heritage while preserving the historical significance thereof. With the advantages of virtual-real mapping and immersive interaction, digital landscape can comprehensively and profoundly restore heritage value. This research attempts to analyze the transformation of thinking on the digital construction of industrial heritage landscape and to broaden the meaning of the term "digital industrial heritage landscape" from the perspective of "virtual-real symbiosis".

Methods The digital construction of industrial heritage landscape has been initially explored at home and abroad, which can be divided into three modes: digital twin, augmented reality (AR) and virtual reality (VR), with both the AR and VR modes being discussed in this research. Taking the Yangshupu Power Plant in Shanghai as an example, the research mainly involves the following four steps. 1) Record information elements. The research adopts such methods as on-site research, historical research and oral interview to collect a large amount of information related to the power plant, and form a database based on the combing and recording of the information collected. 2) Design landscape elements. The research builds a digital base on the ArcGIS platform based on remote sensing images and master plans, and have value elements designed into digital landscape elements that can be presented and experienced. 3) Restore historical scenarios. The research selects four important historical periods, i.e. 1913, 1949, 1979 and 2010, and restores historical production scenarios in the aforesaid periods by means of game engine and 3D modeling, with such scenarios being presented in multiple forms such as audio and text. 4) Enable embodied communication. The research establishes two sets of value communication modes respectively online and offline with the aid of such technologies as AR, VR, blockchain, cloud computing, and artificial intelligence (AI), allowing users to fully engage in the digital construction, utilization, operation and transaction of industrial heritage landscape via mobile or PC platforms.

Results The digital industrial heritage landscape based on "virtual-real symbiosis" may serve as an digital interactive platform that is different from typical digital landscape in such aspects as construction subject, logic, approach and objective. The digital industrial heritage landscape can, by integrating digital technology, exhibit the spatiotemporal properties of virtual-real symbiosis and offer an immersive and engaging landscape experience. The significance of the construction of digital industrial heritage landscape can be reflected in the following aspects. 1) Expand the breadth of value through recording. Keep track of the material and immaterial aspects of industrial history, as well as the historical "layers" of value elements. 2) Improve the depth of value through design. Design the numerous value elements recorded into digital landscape elements that can be presented and experienced. 3) Extend the span of value through elaboration. Have digital landscape elements fully and authentically incorporated into production scenarios in various historical periods. 4) Exploit the diversification of value through dissemination. Create spaces, behaviors, regulations and memories via digital platforms to generate economic activities based on heritage values between the real and virtual worlds, and to offer kinetic energy for their long-term regeneration. In this research, a four-step process for digital construction of industrial heritage landscape is initially devised by employing the technical methods of recording, planning, elaboration and dissemination. This process includes "value component twinning, landscape element regeneration, virtual/actual intergrowth, and activation symbiosis", which may be detailed as follows. Firstly, record value elements; secondly, design value elements into landscape elements; thirdly, integrate landscape elements and restore historical scenarios, which is the prototype of digital landscape; and finally, promote the sustainable revitalization of industrial heritage landscape as the ultimate goal for digital construction of industrial heritage landscape.

Conclusion Starting from the value reproduction of industrial heritage, this research analyzes the connotation of digital industrial heritage landscape by combining the attributes of virtual-real mapping and immersive interaction. Moreover, the research also discusses a framework based on virtual-real symbiosis. In view of the limited expertise of the research team in computer, geographic information and AI disciplines, the research focuses more on the prospective model and the combing method, and some technical aspects need to be further explored. It is worth emphasizing that the ultimate goal for digital construction of industrial heritage landscape should be further serve the real world, and better protect and reuse industrial heritage through value reproduction. Therefore, we should strengthen virtual-real interaction and online-offline linkage with respect to industrial heritage landscape, and provide a path for the development of digital interactive platform such as Metaverse, and sustainable revitalization of industrial heritage landscape through diversified forms such as digital cultural tourism, virtual community and cultural innovation.