4.1. Similarities and Differences in Perceptual Contents
The analysis in this study is based on people’s perceptions of urban parks. The studied urban parks in China are similar in their perceived dimensions, including environmental introduction, facilities and services, landscapes, and activities. Still, they are different in the subject of perceived content. Among the urban parks in Fuzhou that we studied, the main body of comment texts of people’s sharing is more about introducing the background and environment. The first record of perceived content accounts for comparably less. On the contrary, in the survey of urban parks in Beijing, tourists perceive recreational activities and aesthetics and appreciation more frequently, and tourists prioritize the social interaction needs and visual aesthetics brought by the natural landscape, as well as the conditions of transportation facilities and consumption in the park [
21]. In contrast, in the study of Wuhan urban parks, the use of parks has a strong relationship with the characteristics of the surrounding environment [
22]. The public has the highest perceived frequency of recreational experience, followed by the park environment, facilities and services. The area, facilities, and accessibility are the focus of the public’s needs [
23]. We suspect that people in different regions have their own interpretations of what is prioritized in expressions. This is influenced by cultural backgrounds, language habits, social norms, education systems, and communication styles. For example, in China, people in the South tend to be more focused on padding and subtlety, while people in the North tend to be more forthright and straightforward. Meanwhile, the city parks represented by Beijing and Tianjin are mostly scenic tourist areas [
24], which give more prominence to the perception of the architectural landscape dimension, with high-frequency words describing the diverse architectural forms and contents as well as elaborating on the feelings of the intermingling of culture and history [
25]. On the other hand, the representative urban parks in Wuhan and Fuzhou are perceived less regarding historical and cultural aspects. One of the reasons for this situation is the difference in urban environment. Horizontally comparing the review texts of Fuzhou city parks, we also found that the parks with a long history have more review introductions. Moreover, the texts of the comment can better reflect the perception of cultural accumulation and historical heritage. Combining cognitive content and principal component analysis, we also found that people are more likely to notice the changes in space and the things within it over time.
Compared with China, the construction of foreign city parks does not clearly emphasize the historical and cultural aspects, but rather focuses more on the service functions of the parks, including a variety of social activities as well as the services provided by the facilities and venues. This approach judges the functionality of parks from a more objective perspective based on the user’s point of view. However, users of domestic parks have relatively little intuitive experience with the facilities unless the service function seriously affects them. This is mainly because China’s urban parks are partly constructed and planned on the basis of historical and cultural sites such as gardens, and these parks have been transformed from private to public spaces, forming Chinese urban parks with distinctive characteristics [
26]. This difference reflects the philosophy and focus of different countries and regions in urban park planning.
Combining the classification ratio of visitors’ routes and landscape perception content, we found that in urban parks that are closer to residential areas, such as Fuway, Huahai Park, and West Lake Park, the percentage of comment texts describing personal behavior will relatively increase, accounting for 15% or more. On the contrary, in Forest Park, a park farther away from the city, the proportion of personal behavior is only 0.75%. Personal behavior, as the most substantial part of the subjective will of the individual, best reflects the purpose of the people. Walking has also become one of the main activities carried out by people in the city parks, often for physical exercise and to relieve psychological pressure. The behaviors characterized by words such as ‘Daka’, ‘exercising’, ‘taking pictures’, and ‘strolling’, are also popular among people. Similar activities such as exercise, relaxation, and plant viewing are also practiced in foreign countries [
27]. We have also noticed that with the development of new media technology and the popularity of short videos, the Daka trend has often become one of the primary reasons people travel to China. Private management companies usually operate overseas city parks, so there are frequently keywords for commercial activities such as ‘bazaar’ and ‘food’ [
28]. In China, activities of a commercial nature are usually separated into specific areas (e.g., commercial streets or pedestrian streets), such as the practical example of Yantai Hill Commercial Walking Street in Fuzhou. On the other hand, urban parks are more focused on public non-profit welfare rather than profit. Therefore, activities such as chrysanthemum and goldfish exhibitions are reflected frequently in the review text. In subsequent research, we plan to investigate different types of parks in various regions, even worldwide, and thereby synthesize and compare the empirical findings in differentiated social and cultural contexts.
In the text, we also found that when users express negative emotions, they tend to be closely related to the negative events experienced by the individual. Thus, comments against a uniform thing appear to present polarized emotion, which is in line with the findings of Sim et al. [
29]. Our study also validates the conclusion that Lai and Deal’s natural factors produce positive emotions for people’s feelings [
30]. However, the results in the semantic segmentation of images show that the green visibility rate of the six city parks is close to 33%. Among them, there is still a gap between the 42.24% green space rate and the 45.40% green coverage rate of Fuzhou City in 2020 [
31]. This implies that people take photographs to differentiate themselves from the large area of greenery especially. Besides, they also prefer to take the elements, such as buildings and landscape vignettes, as the main subjects of the photographs.
4.2. Suggestions for Urban Park Space
Based on the sentiment analysis of park reviews, we search for attraction name keywords to extract and categorize the data of significant attraction reviews, obtaining the number of reviews to calculate the sentiment mean of the review information. The obtained results are assigned to the park attractions to generate the emotional heat map (
Figure 7). The ArcGIS 10.5 platform is employed to conduct the kernel density analysis and then visualize the sentiment mean value to supplement the spatial data. The perceptual heat map consists of the heat maps of photo location points and tourist routes obtained by density analysis.
In the emotional heat map, fewer attraction names could be retrieved. In conjunction with the perceptual heat map, the higher density of stopping to take photos of location points and visitor routes only partially overlapped with the distribution of higher sentiment in the sentiment map. We believe that it may be that when people comment on urban parks, they give more prominence to the overall description of the park, and they will only highlight the events that caused negative impacts, rather than describing each attraction in detail. This is a reminder to upgrade the landscape in orientations with high perceived heat values to make it more attractive. Less research has focused on the emotion or mood of landscapes regarding their geospatial location. The study by Brian Park and Kim et.al. (2020) indicated visitor emotions through the two axes of happy and not happy and whether or not the landscape can arouse emotions in a total of four quadrants of data to represent visitor emotions. The emotion values were shown in geospatial locations to derive a tour path that evokes pleasurable emotions [
32]. In contrast, they removed comment texts that contained two or more emotion dimensions, ignoring the complexity and diversity of emotions that people expressed in the texts. This approach fails to adequately capture the richness and multilayered nature of emotional expression, which may lead to a one-sided understanding of emotional data. This gap has been partially filled in our study by using segmenting sentences, including all sentences containing with different emotions in the one sentence. Based on the research results, we can identify some problems in the urban parks studied. For example,
Figure 7c shows that the zoo located in the southwest direction in the Forest Park area, despite its high median emotional value, is not well distributed by the surrounding roads due to its distance from the entrances and exits, and it is recommended to improve the accessibility within the area by truncating the curves. Similarly, (
Figure 7f) suggests upgrading the entrances to Fuway, except for Exit 3 and Exit 5, and optimizing and upgrading the road from the southeastern entrance to the central observation deck of Yantai Hill Park. In the future, we can increase the points of attractions in the sentiment distribution map by separating the attractions with explicit references to get a complete map, which can bring more relevant and practical suggestions for urban parks. It is also possible to upgrade and simplify converting comments to attraction emotions and upload them to the cloud to realize real-time updated emotion distribution maps. The purpose regarding interaction design, real-time crowd monitoring, and even user experience-guided design can be achieved better.
Based on the results of the PCA analysis, we explored how different environmental factors affect people’s perception of urban parks, and relevant keywords were retrieved in the comment text. We also generated word cloud maps after word splitting. The results show that ‘Breeze’ is most easily perceived in urban parks and is often accompanied by the emotions of comfort and idleness (
Figure 8a). The perception of ‘Wind’ is closely related to ‘Road’, which may be related to Chinese people’s habit of walking. In addition, the scenery around the road and the undulation of the terrain are also primary perceptions (
Figure 8b). Attention to ‘wall’ was focused on the historical buildings in Yantai Mountain Park (
Figure 8c) Among the buildings, the red brick wall and the unique classical architectural style became prevalent for photo-taking. The ‘Door’ as a keyword becomes the main component due to the Daka. However, the review text mainly describes several entrances and their locations (
Figure 8d). It does not develop a detailed description of the ‘Door’. The ‘Ground’ does not appear as a distinct environmental feature in the word cloud map. The ‘Sky’ is notable for its color, whether the blue of a clear sky or the brilliance of a sunset (
Figure 8f). ‘Sidewalks’ were ignored due to the small sample size. Overall, environmental factors influence people’s perception of urban parks through specialness, clocking behavior, and comfort. This also indicates three main directions for the enhancement of urban park spaces.
Looking back at the review texts, we found those are relevant to children possessing the feature of concentrated perceptual theme. They chiefly focus on fun, children’s parks, and children as a group. The content usually emphasized child-friendly entertainment features and came from moms’ and dads’ exchanges and opinions. By comparing
Figure 6 and
Figure 9, we also noticed that the comment texts about children were posted at a more even time. Unlike other themes, the level of perception changes yearly, showing a continuous demand for unique spaces for children.
4.3. Comparison of Analytical Methods
In this study, since the themes obtained from the clustering of the LDA theme analysis model were unsatisfactory, we used it only to extract the core ‘themes’ of the review texts, and did not adopt the clustered themes. Compared with the word frequency of textual clustering, which is also the main content of landscape perception (
Figure 4), the LDA theme model highlights the core content of landscape perception, consistent with Shang et al.’s study [
21]. Although the theme model weakens the influence of lengthy descriptions of scene background and introduction, it also inevitably reduces the evaluation of subjective emotions and more detailed descriptions of the current scene, such as ‘like’ and ‘suggest’, ‘saw’, and ‘weekend’.
While analyzing a comment text, in addition to conducting an in-depth analysis of the content of the text, researchers usually examine it in depth from several perspectives. The time factors and the influence of environmental conditions are two commonly used entry points. Temporal factors may include the specific period in which the comment was posted, such as the timeliness and the trend over time. External conditions, on the other hand, may cover the potential impacts of ecosystem services, park types, and landscape attributes on comment content [
33,
34]. Taking this aspect into account, in our study, we therefore also examined the influence of the external physical environment and the occurrence of specific events on perception. This is shown by the fact that things linked to memory and elements that affect humans directly have a greater impact on perception. In addition, researchers conduct detailed categorization and cluster analysis of users of reviews based on their primary characteristics, such as age, gender, and region. By categorizing these users into groups or clusters, researchers can more specifically explore the influencing factors behind each group and how these factors affect the formation of review content and attitudes under different conditions [
30,
35]. Koblet and Purves translate specific descriptions of reviews into easily observable forms of data [
36]. We discard a detailed and line-by-line textual content analysis due to the sheer amount of comment data, even though their approaches inspired our analysis. In our study, we innovatively switch to using sentiment to replace the results of the public’s perception of something. However, we still need to study further how to determine what information the comments convey. Currently, the common recognition break model usually uses punctuation as the basis for simple sentence division and classification. The large language models, such as Chatgpt4.0 or Claude, present a relatively high accuracy in analyzing the text and breaking sentences. However, they still suffer from the problem of error-prone batch processing of comment text.