Abstract:Important Agricultural Heritage Systems (IAHS) is regarded as a typical reserve for the sustainable utilization of natural resources. It is comprised of unique land-use systems and agricultural landscapes formed by long-term co-evolution and dynamic adaptation of rural communities and their environment. IAHS sites are rich in biodiversity and support of local socio-economic and cultural development. They also play a positive role in coordinating community livelihoods and ecological protection through their soil and water management strategies, knowledge systems, and cultural connotations. Therefore, it is of great significance to assess the value of IAHS for adaptive IAHS management per se, as well as optimizing the protected area system and its zoning-based management according to human-environment interactions. Our study first reviewed the value systems of related concepts, focusing on natural resource assets, ecosystem functions and services, and various types of natural and cultural heritage to generalize the value typology and assessment methods for heritage systems and their key elements. We then examined the uniqueness of IAHS based on our understanding of the general agricultural heritage systems (AHS) and the more specific Globally Important Agricultural Heritage Systems (GIAHS) to ensure that characteristics such as complexity, vitality, and strategy were fully reflected in the value system. IAHS is comprised of both material and non-material parts. Its' complexity indicates the assimilation of values from natural and cultural heritage, as well as cultural landscapes. Vitality implies the system's dynamics based on its historical and current value as an adaptive system. Strategy defines the positive externality of IAHS towards people beyond its local area, determining its contribution to regional and global sustainable development strategies. Afterwards, the value typology of IAHS was proposed. The value system was firstly divided into existence and potential values to reflect the impact of IAHS on the current and future generation. The existence value was further separated into carrier and service values. The carrier value is the intrinsic value based on the physical formation of agricultural land as an asset stock during its historical period. The service value is the measure of flow from the stock. It is composed of nine values, namely the product value, ecological value, sci-tech value, social value, aesthetic value, cultural value, historical value, spiritual value, and brand value, and is further divided to 25 value elements at the lowest level. We also proposed possible evaluation methods and statistical approaches targeting at potential indicators of the existence value to obtain the monetary value of certain IAHS to better implement this multi-layered value system in policy making and conservation management. Key methods were selected from practices that evaluated ecosystem services, farmland, and natural resources, including the direct marketing method, substitutable marketing method, and simulated market method. Non-material value elements, which usually were only valued quantitatively, were discussed to determine the difficulty and possibility of quantitative accounting. As a result, the value typology can help managers identify IAHS conservation focal points according to the value connotation. The existence value must be well preserved. The potential value should be further studied. The conservation of the carrier value is mainly dependent on local farmland protection. Some service values benefiting large areas are better protected via regional cooperation. As a result, this research revealed the values embedded in human-environment interactions in the IAHS and interpreted their importance in maintaining a harmony between human and environment; thus providing a theoretical basis for spatial integration and management optimization of protected areas, as well as coordinative decision-making for regional conservation and development. It also provided a whole set of value systems and evaluation methods for the monetary value of IAHS; synthesized from quantitative or qualitative methods used in ecosystem services, natural resources assets, natural and cultural heritages, and brands.