Abstract: The construction of a field observation network for forest ecological inventory system (FON-FEIS) can provide data support for the research of forest ecological processes, the assessment of ecological functions and the delivery of ecological values, thus promoting the improvement of forest ecosystem quality and its carbon neutral capacity. Currently, the lack of longterm, standardized ecological data is one of the major constraints on the effective assessment of ecological benefits and the implementation of ecological restoration projects. It is therefore critically needed to develop a FONFEIS for Yunnan Province, China. Firstly, an index system, involving temperature, water, vegetation type, terrain, and functional ecological zone, was constructed based on the factors driving forest ecosystem functions. Then, GIS spatial analysis technology was used to identify forest ecological zones. Finally, the FONFEIS in Yunnan Province was constructed in combination with the layout idea of forest ecological stations, while the monitoring accuracy of the network layout was evaluated from the perspectives of forests, key ecological function zones, and priority zones for biodiversity conservation. The results showed that the optimal FONFEIS was achieved when Yunnan Province was divided into 22 forest ecological regions and 31 forest ecological stations were deployed, including 6 key stations, 11 basic stations, and 14 monitoring stations. Currently, 22 stations are under planning and 9 stations were established. Within this network, the accuracy of monitoring reached as high as 94.29%, 94.76% and 87.99% on the levels of forest, key ecological function area, and biodiversity conservation priority area, respectively. The distribution of 25 forest ecological stations matched that of the three key ecological function areas and two biodiversity conservation priority areas in Yunnan Province. In conclusion, this network enables the effective, continuous observation and inventory of forest ecosystems in Yunnan Province, which provides  not only the requisite data for the assessment of forest ecological function and ecological benefits, but also the important information to assist decision making for major ecological projects and international fulfillment.

Key words: forest ecological zoning, GIS, spatial analysis, network layout, monitoring accuracy evaluation.