Objective  In the context of urban construction transformation in the new era, urban historical parks are in urgent need of conservation and management from the perspective of heritage. In the renovation and renewal of urban historical parks, there still exist a number of problems. For example, historical relics may change over time, new landscape may fail to match the historical appearance, or the public may be incapable of effectively perceiving the historical or cultural value of historical sites. The reason for this is that historical information fails to play its due role in the renewal, conservation and management of historical parks, and whether historical information can actually play its role is crucial indeed. The development of 3D information modeling technology provides unprecedented opportunities for heritage landscape conservation and management methods, especially in terms of the recording and dissemination of information, but there are few systematic researches on this aspect for historical parks. Therefore, it is necessary and urgent to study the construction of information models for historical parks that are integrated with cultural heritage conservation and management.

Methods  This research adopts sociological research methods to analyze the conservation and management needs of Shanghai historical parks, and applies computer discipline methods to construct an information model, which mainly involves the following steps. 1) The research conducts data collection mainly in the form of semi-structured interviews, supplemented by questionnaire research, which involves a total of nine interviewees (including designers, engineers and managers) who ever experienced historical park renovation within the past 20 years. In particular, the managers involved are required to have more than 20 years of experience managing historical parks. By obtaining the interviewees' real experiences and memories of historical park renovation events, and using NVivo software to analyze and summarize the documents, the research summarizes the contents and needs of historical park conservation and management. 2) Drawing on the four-dimensional information model theory, level of detail (LOD) theory, and family construction analysis theory in building information modeling (BIM), the research constructs a historical park information model based on the level of knowledge (LOK). In addition, the research adopts the digital technology to provide a complete and consistent information base in combination with the actual situation for the virtual 3D model established. 3) The research applies the virtual reality technology to generate 3D graphics based on panoramic photos, applies the dynamic environment modeling technology to display four-dimensional spatio-temporal information, and applies the Web technology to build an interactive network platform.

Results  The research clarifies the current status of conservation and management of historical parks, and proposes a framework for the whole-process conservation and management of historical parks. The framework is composed of the five parts of heritage survey, dynamic monitoring, assessment and analysis, implementation and disposal, and heritage interpretation, further perfecting the content of the overall conservation management framework for landscape heritage in historical parks. In addition, the research classifies relevant information according to the work requirements of the five aspects of historical park conservation and management, and achieves four-dimensional semantic coding of the information. On this basis, the research proposes the level of knowledge (LOK100 – 400) model for historical parks with reference to the LOD technology of BIM, with each level of LOK corresponding to different application scenarios, which can be detailed as follows. LOK100 is intended for public enjoyment, which can provide public-oriented tours and displays; LOK200 is used for daily management, which can help managers realize data query updates corresponding to spatial entities; LOK300 serves for professional research, which can provide relevant researchers with tools for observational studies and the basis for intervention actions; LOK400 is designed for dynamic monitoring to meet the monitoring and supervision needs before and after intervention, which is a comprehensive information model that can simulate the whole-process conservation and management of historical parks. Based on the above results, the research establishes an information platform for Shanghai historical parks, which is functional for the whole-process conservation and management of urban historical parks, covering all such aspects as heritage survey, heritage interpretation, dynamic monitoring, evaluation and analysis, and implementation and disposal; in addition, the research constructs the information model of LOK100 – 300 with Shanghai Fuxing Park as an example, which can partially realize the ideas and main functions proposed by the theoretical study.

Conclusion  At the theoretical level, this research proposes an alternative four-dimensional information model construction system based on the knowledge hierarchy of the LOK information model, which strengthens the relevance and effectiveness of the digital information model. At the application level, the research proposes a Web-based multifunctional, information-sharing, and real-time feedback information exchange platform for historical parks. The platform is inclusive enough to store multifarious and heterogeneous information, which can connect the whole-process conservation and management with information models at all levels, create Web platform interfaces for all stakeholders, and thus become a transparent and open platform under common construction and governance that can achieve information sharing and mutual benefits. The Web-based dissemination of the platform can attract more stakeholders, including managers, the public, traditional artisans, monitoring agencies, experts and scholars, to freely communicate and exchange information resources on this platform. The information model construction method proposed in this research is still at the exploratory stage. Due to research time and funding constraints, the proposed information model construction method has not yet been fully implemented in the empirical application of Shanghai Fuxing Park, and will be followed up and deepened in subsequent researches.