Objective Based on the current construction background of national cultural parks in China, sustainable and high-quality development represented by the Long March, the Great Wall, the Yangtze River, the Yellow River and the Grand Canal has become an epochal proposition of Chinese landscape research and practice. In view of the necessity for systematic identification, collaborative evolution, and quality and efficiency improvement of regional landscape with typical red-culture characteristics, the in-depth research on the microdomain analysis and spatial evolution mechanism of red landscape along the Long March has become the realistic basis for the current spatial construction and development of the Long March National Cultural Park. Microdomain has become one of the interdisciplinary concepts in current landscape theory, which refers to the basic regional range that constitutes the in situ landscape system. Evolving from the original environment under the combined action of ecological, social, cultural and other factors, microdomain has the attributes of locality, diachrony and entirety. The coordinated development of landscape management and multi-source spatial data fusion provides theoretical support for spatial simulation and analytical approach for microdomain identification and acculturation of red landscapes along the Long March route.

Methods This research constructs a research framework of "identification-acculturation" for red landscape microdomain. Taking the Long March route of the 25th Red Army as an example, the research, targeting the intensive red landscape resources and the integration between them and the natural and built environments along the Long March route, establishes an element identification system for red landscape microdomain that integrates multi-source heterogeneous data. Then, the research expounds on the correlation method and basic technology for microdomain identification and acculturation, and subsequently puts forward the construction strategy for microdomain in combination with the acculturation effect of red landscape. The research mainly contains two stages: identification and determination of red landscape microdomain; spatial acculturation and assessment of red landscape microdomain. 1) The research summarizes the resource elements of red landscape through such technical means as collecting red landscape samples, reviewing historical literature and sorting out spatial information data, and establishes an element identification system suitable for red landscape microdomain in combination with landscape type research. Based on the principles of iconicity and identity and the characteristics of relevance and spillover, the research has core landscape points and associated environmental elements identified and further loaded into the ArcGIS platform to complete data positioning, and develops a microdomain suitability analysis method based on the minimum cumulative resistance (MCR) model to analyze and determine microdomain suitability evaluation indexes, and quantify and generate microdomain spatial boundaries and their influence ranges. 2) The research integrates the basic data about red landscape microdomain, establishes an assessment system for spatial acculturation characteristics of red landscape microdomain and, by the AHP entropy-weight method, calculates the factor weights for spatial acculturation in the assessment system. Besides, the research has the distance function introduced and superimposed with weighting factors, and establishes a three-dimensional matrix model by the factor superposition method to quantitatively evaluate the three dimensions of culture carrying, conservation value and spatial development. Additionally, the research determines the classification threshold of microdomains in combination with the natural breakpoint technology, based on which classifies microdomain types and proposes management policies.

Results The results show that based on the systematic identification of microdomain elements, the simultaneous analysis involving the MCR model, the weighting factor superposition method, the acculturation evaluation system for landscape microdomain and the three-dimensional matrix model can effectively achieve microdomain identification and classification assessment of red landscape along the Long March route. Yujiahe and other research cases also show that the management of red landscape along the Long March route of the 25th Red Army should adhere to the principles such as protection priority, inheritance enhancement and development appropriateness. Relevant practice needs to be classified and controlled in combination with microdomain identification and acculturation assessment, so as to strengthen the original attributes of red landscape, thus improving the acculturation efficiency of microdomain, actualizing the potential of landscape conservation, and helping improve the quality and efficiency of Long March red landscape. Meanwhile, relevant researches on the new field of the national cultural park are both multi-stage and exploratory. A series of frontier issues, such as the contemporary annotation and development of core concepts, collaborative innovation of analysis system and methods, problem orientation and realistic appeals, decide that the microdomain system research still needs to be further explored.

Conclusion This research and other relevant researches can provide technological approaches for the protection and development of red landscape resources, and provide foundation and referential methods for the construction and continuous improvement of the landscape microdomain system and the orderly evolution and high-quality development of the red landscape system under the mechanism of national cultural park in China.