## 2 Materials and Methods  
### Study Overview and Selection of the Study Area  
The final step in analyzing suitable cultivation sites for crops in mountainous areas using GIS involves generating overlay operation data (composite suitability map) with various environmental factors relevant to optimal growth conditions and then reclassifying these data. The novelty and originality of this study can be attributed to the analysis of suitable cultivation sites for GE using various reclassification methods applicable to this reclassification process and to the comparison of the results obtained from each method. To this end, this study explored new GE cultivation sites in mountainous areas using various methods, focusing on Muju County, which is the main GE production area in South Korea. As of 2022, the total land area of Muju County is 63,207 ha, of which 51,165 ha is forested, resulting in a forest cover rate of approximately 81% [37] (Figure 1).  
Selection of Factors for Suitable GE Cultivation Site Analysis and Assignment of Weights Based on Criteria  
The environmental factors necessary for analyzing suitable cultivation sites for GE, that is, the optimal growth conditions for GE, were selected based on the Korea Forest Service's Standard Cultivation Guidelines for Forest Products [38], Rural Development Administration's Medicinal Mushroom Guidelines [39], and Muju GE Project's Cultivation Manual of _Gastrodia elata_[40]. The individual factors and criteria required for the artificial cultivation of GE, as provided in the above-mentioned literature, were integrated to select the final factors. The final factors selected to analyze suitable cultivation sites for GE included elevation, aspect, slope, forest type (tree species), effective soil depth, soil texture, soil moisture, organic matter content, drainage, growing season temperature (April-November), active growth period temperature (June-October), summer temperature (June-August), and winter temperature (December-February). For temperature factors, the growing season and active growth period temperatures were averaged using monthly average temperatures. However, the summer and winter temperatures were averagedusing the monthly average maximum and minimum temperatures over 10 years. This is because GE's growth is inhibited when the summer temperature exceeds 30 \({}^{\circ}\)C and perishes when it exceeds 35 \({}^{\circ}\)C. Additionally, GE is sensitive to extreme temperatures, as it freezes to death when the winter temperature falls below \(-15\)\({}^{\circ}\)C. Therefore, regions with these temperature conditions were defined as extreme-temperature areas, unsuitable for GE cultivation, and were excluded from the composite suitability map (Table 1).  
Meanwhile, the composite suitability map was generated by applying weights to the criteria of various factors and performing mathematical operations on these factors. The weights were standardized (evenly divided) to values between 0 and a maximum of 1 based on the ranks of the criteria for each factor. The ranks of the criteria for each factor were assigned by evaluating their importance based on the frequency of mentions in the GE cultivation guidelines [38; 39; 40]. Equation (1) is a reformulated formula for converting weights into standardized scores based on the ranks of the criteria for each factor [41], with differentiated weights shown in Table 1.  
\[Weight_{k}=\frac{1}{n}\times\left[n-\sum_{k}^{n}(k-1)\right] \tag{1}\]  
where \(n\) represents the number of criteria for each factor and \(k\) represents the rank of the corresponding criterion.  
Figure 1: Location of the study area. Muju County is located in the northeastern mountainous region of Jeonbuk State, South Korea. The locations of the automatic weather stations (AWSs) used in this study, provided by the Korea Meteorological Administration, are marked with red dots.