Sustainable University Campuses: Temporal and Spatial Characteristics of Lightscapes in Outdoor Spaces

Abstract

A lightscape, as a special visual landscape, has unique temporal and spatial characteristics that traditional photometric measurements and descriptions struggle to capture accurately. Despite their significance, there is a lack of in-depth understanding of the on-site perception of lightscapes’ temporal and spatial characteristics, including in outdoor university campus spaces. This study aims to explore the temporal and spatial characteristics of outdoor lightscapes on university campuses and their potential perceptual influencing factors, providing sustainable design, planning, and management suggestions for campus lightscapes. This study was conducted in the Wushan Campus of the South China University of Technology. It employs a “lightwalk” method for on-site perception evaluation, combining qualitative and quantitative approaches to investigate the temporal and spatial characteristics of lightscapes in outdoor university campus spaces and the effect of temporal and spatial factors on lightscape perception. The main findings are as follows: (1) Meteorological, architectural, and biophilic lightscape dominate the outdoor campus lightscapes. (2) The temporal and spatial characteristics of the lightscapes are affected by changes in natural light, the transition of light sources from day to night, human activity patterns, and the functional characteristics of the site. (3) The correlation between meteorological and traffic lightscape types and lightscape perception is diminished during the evening periods. This method should be a good way to optimize water and architectural lightscape at night to alleviate discomfort. (4) In green-shaded spaces, the association between meteorological, architectural, and traffic lightscape types and the evaluations of emotional, luminous, and eventful aspects is significantly enhanced, suggesting an increase in such spaces to improve lightscape experience quality. This study advocates that the construction of buildings and environments should be “human-oriented”, paying attention to the scientific foundation that humans perceive the habitat environment through the “five senses”. Research on lightscapes’ temporal and spatial characteristics, exploration of the temporal and spatial modes of lightscape perception, and avoiding energy waste and light pollution are conducive to the design and construction of university campuses in line with the principles of sustainable development. The lightscape optimization strategies derived from this study can not only provide practical guidance for the design and management of campus but also may offer valuable recommendations for planning sustainable campus development.

1. Introduction

1.1. Research Background

The university campus is the primary place for student and faculty learning, living, and recreational activities. As a special and significant medium in outdoor spaces, “Light” not only contributes to rendering atmosphere, enhancing spatial perception and architectural expression [1,2], but also plays a positive role in improving individuals’ physical and mental health [3], behavioral activities [4], and well-being [5]. However, unscientific lighting has not only led to light pollution but also negatively affected human health and damaged natural ecosystems [6], which runs counter to the development of a sustainable ecological human habitat environment. Now, the “Lightscape” has been advocated as a new discipline in parallel with the “soundscape” and “smellscape”, and multifaceted landscape creation is also being emphasized [7]. A “sustainable” environment emphasizes maintaining and enhancing ecosystems to service and improve humans’ well-being [8,9]; this context aligns perfectly with the basic idea of a “Lightscape”. A lightscape focuses on deeper and inner interaction between light and humans, emphasizing human perceptual experiences, thus providing feedback for the continuous improvement of a quality sustainable environment.

A “lightscape” is a particular aspect of the visual landscape. It refers to scenes primarily composed of light and shadow and their variations or scenes where strong visual impressions are evoked by light and shadow and their changes [10]. In further description, a natural lightscape is mainly formed by natural light sources, an artificial lightscape is mainly formed by artificial light sources, while a composite lightscape combines both. Lightscape studies advocate for considering the overall scene characteristics formed by light and the surroundings from the perspective of human subjective perception and experience. They emphasize how a lightscape is perceived, appreciated, and understood by individuals or social groups. It also highlights the overall scene constructed by “human-light-environment” interactions from both spatial and temporal dimensions.

The relevant research findings show that for the study of special landscapes where perception and experience are paramount, such as soundscapes and lightscapes, a combination of qualitative and quantitative methods is currently considered the most scientific [11,12]. The approach used in this study is cross-comparing landscape perception and light environment assessments in outdoor campus spaces while incorporating reported lightscape studies and multisensory landscape theories to determine the strategy for lightscape perception evaluation (by a lightwalk). Therefore, this literature review is primarily divided into two parts: (1) research on landscape perception in outdoor university campus spaces and (2) advances in multisensory landscape and lightscape research.

A landscape is a perceived spatial scene characterized by the interaction between natural and/or artificial factors and endowed with value due to its inherent aesthetic, cultural, or other human-perceptible advantages [13]. The existing literature on outdoor campus spaces research has shown that some visual elements, including natural features such as grassy lawns, flowers, water bodies, and open forest vegetation, are attractive elements that can evoke positive emotions and reduce distractions [14]. Good service facilities, such as public amenities, paved landscapes, and pathways, along with service-type activities, can enhance the experiential quality of outdoor spaces [15]. And the non-physical landscapes of light, sound, and smell are equally important aspects of human experiences [7,16,17]. Variations in natural light, dynamic tree shadows, etc., contribute to enhancing people’s sense of relaxation, excitement, and satisfaction [18]. The manner in which lighting is used can have a significant impact on individuals’ mental restoration [19].

The multisensory landscape theory emphasizes that people’s perceptions and appreciation of landscapes is an integrated process that involves visual, auditory, olfactory, tactile, thermal, and other sensory inputs, leading to an overall impression and judgment process [7]. Historically, “light” has been used as an important landscape element in architectural construction [20]. The classical Chinese garden embodies a rich fusion of soundscapes, lightscapes, and smellscapes while considering both spatial and temporal dimensions, ensuring beauty everywhere and at all times [21]. The existing literature shows that lightscapes formed by special light sources possess unique temporal and spatial characteristics, developmental origins, as well as visual aesthetics and cultural characteristics in the context of traditional Chinese culture, such as moonlight lightscapes and firefly lightscapes.

In terms of lightscape perception, there is a positive impact of a lightscape on urban safety perception [22] and social interaction [23]. Pietro Matracchi et al. explored the role of different light intensities in inducing the subjective mystique and spiritual atmosphere of religious buildings [24]. Kong et al. studied the significant impact of lightscapes formed by various types of daylight openings on visual comfort and emotional feelings [25]. The author’s previous studies on lightscape perception have shown that people’s lightscape experience is strongly correlated with the nature of social interaction, the cultural context of the place, and temporal characteristics [26]. Meanwhile, the overall perception of a lightscape is influenced by color richness, typological distinctiveness of the lightscape, and lightscape preferences [27,28]. While it is evident that the type and environmental context have a significant impact on lightscape perception, the presentation of a lightscape and people’s experience are both markedly temporal and spatial dynamics. However, there is still a gap in the research on how temporal and spatial factors specifically affect the perception of lightscapes on outdoor university campuses. This study also hopes to provide support for summarizing the general laws of lightscape perception by revealing temporal and spatial characteristics in outdoor university campuses’ lightscapes.

1.2. Research Objective

This study was conducted on the Wushan Campus of the South China University of Technology (SCUT) in Guangzhou, China. It employs the lightwalk method and integrates qualitative and quantitative data to summarize and analyze the temporal and spatial characteristics of the lightscape in outdoor campus spaces and how these characteristics impact the experience, with the research objectives being as follows:

• Clarifying the composition characteristics of the identified lightscapes in the outdoor campus spaces;
• Investigating the temporal and spatial characteristics of lightscape perception in the outdoor campus spaces;
• Exploring the relationship between lightscape perception and lightscape types under the influence of time and space factors.

2. Research Methods

2.1. Field Study

The Wushan Campus of SCUT, located in Guangzhou, Guangdong Province, China, covers approximately 2740 acres. It has its roots in the National Sun Yat-sen University’s Shipai Campus, founded in 1924 by Dr. Sun Yat-sen. The campus retains several well-preserved Lingnan-style buildings from the Republican era, and contemporary architecture clusters with the new Chinese style as well as modern buildings also stand. The lightwalking site is located in the core landscape areas of the campus, which also serve as the main areas for daily activities and relaxation for students and faculty.

2.2. Lighscape Classification

This study classifies the campus lightscapes into 5 types based on the carrier characteristics, as shown in

Table 1. Classification of light and shadow elements of campus lightscape.

Type	Subcategory	ID	Category
Meteorological lightscape	Direct light	1	Daylight 1,2
		2	Sunset 2
		3	Sunset glow 2
		4	Moonlight 3
		5	Skyglow 3
	Shadow	6	Cloud shadow
Water lightscape	Reflection	7	Lake reflection
		8	Lake wave light
Architectural lightscape	Shadow	9	Building shadow
		10	Light and shadow created by grid construction
	Reflection	11	Building glass reflection
		12	Building facade reflection
	Silhouette	13	Outline of building in distance
	Direct light	14	Architecture decoration lighting 2,3
		15	Billboard lighting 2,3
		16	Light from windows 2,3
Traffic lightscape	Shadow	17	Vehicle shadow
	Reflection	18	Vehicle glass reflection
	Direct light	19	Street lighting 3
		20	Vehicle lighting 3
Biophilic lightscape	Shadow	21	Dappled light
		22	Plant shadow
		23	Landscape structure shadow
		24	Light and shadow created by people, animals, and their movements
	Reflection	25	Sunlit leaves
	Silhouette	26	Outline of plants in distance
	Direct light	27	Landscape decoration lighting 3

¹ present only in the morning period; ² present only in the afternoon period; ³ present only in the evening period; the rest are present in all three time periods (author’s own work).

. This classifies based on the consideration that lightscape is produced depending on the landscape structure and form, while they are mainly shaped by a combination of human activities, biological processes, and geophysics [29]. These types of lightscape are caused separately by meteorological phenomena, the water-reflection phenomena, building materials and construction, traffic elements, and biophilic designed elements. Correspondingly, these types of lightscape will be referred to as “meteorological”, “water”, “architectural”, “traffic”, and “biophilic” lightscapes hereinafter.

After removing the lightscape categories not selected by half of the subjects during this lightwalk, a total of 27 lightscape categories were documented, as presented in Table 1.

2.3. Lightwalk

Three lightwalk events were conducted on 16–18 October and 6 November 2021 at different times: morning from 10:00 to 11:30, afternoon from 16:00 to 17:30, and evening from 19:00 to 20:30 (all times in Beijing Time, BJT); all in stable weather with no rain or wind, average temperature of 22.3 °C, and standard 4.8 °C deviation.

Figure 1 shows the lightwalking route and evaluation points, which were determined by taking the diversity of spatial form and function into account after multiple pre-surveys. The route passes through some key spaces of the campus, including historical buildings (department office buildings) (#1, #9), square (#2, #4), academic buildings and their activity area (#5, #8), lakeside trail (#3, #7), and the central island of the lake (#6), totaling approximately 1.5 km in length with nine evaluation points. It focuses on outdoor activity spaces that exhibit rich variations of light and shadow under normal daylight or regular artificial lighting conditions, excluding the surroundings of buildings with special lighting requirements. The route was also not deliberately made to overlap with the students’ complete daily activity routes.

2.3.1. Subjective Data of Lightscape Perception

A questionnaire was employed to assess the subjective responses of lightscape perception during the lightwalk process.

Part 1 describes the subjects’ recognition of the types of lightscape in the current area. All subjects were asked to select lightscape categories (select 3–7 items) that made a deep impression from the list (already with brief descriptions for anyone) in the questionnaire, then rank the selected categories based on their perceived intensity and rate them based on their level of preference (5 = very like~1 = very dislike). “Perceived intensity” refers to the subjective ranking of lightscape categories (rank 1 = 7 points ~rank 7 = 1 point). After assigning values to ranked lightscape categories, the perceived intensity scores for each lightscape type were calculated.

Part 2 is a collection of subjects’ overall perception of the lightscape. Based on the three “people-light-environment” elements, a Semantic Differential Scale was utilized for the questionnaire with 23 descriptive adjectives as evaluation indicators for overall lightscape perception (

Table 2. Semantic Differential Scale details [30,31,32].

Variable	Issues
Overall lightscape perception	Light impression	Bright–dim
		Glaring–soft
		Even distributed brightness– Uneven distributed brightness
		Direct–indirect
		Warm–cool
		Colorful–uncolorful
		Dynamic–static
		Rhythmic–rhythmless
	Site atmosphere	Cultured–uncultured
		Seasonal–seasonless
		Beautiful–ugly
		Harmonious–discordant
		Ordered–disordered
		Natural–artificial
		Traditional–modern
		Social–non-social
		Safe–dangerous
	Emotional responses	Satisfied–unsatisfied
		Comfortable–uncomfortable
		Pleasant–unpleasant
		Vibrant–dull
		Interesting–boring
		Impressive–unimpressive

Author’s own work.

).

2.3.2. Photometric Data of the Lightscape

High Dynamic Range (HDR) photography techniques have been used to obtain the environmental luminance parameters at each evaluation point [33]. After absolute point calibration of a luminance meter and a relative scene calibration using a calibrated camera and Photomatix Pro 6.0 software, it is possible to explicitly convert RGB pixel value into a luminance variable in a defined camera response curve. This study employed a Panasonic DMC-GF3 camera (Panasonic Corporation of China, Beijing, China) with a standard lens (14–42 mm/F3.5–5.6) calibrated by a Minolta LS-100 luminance meter (Konica Minolta, Inc., Tokyo, Japan). Finally, the luminance distribution including the average brightness of the main viewpoint, along with its numerical values, was obtained using Hdrscope software (https://courses.washington.edu/hdrscope/index.html, accessed on 22 December 2021).

2.3.3. Lightwalking Design

A total of 51 subjects (22 males, 29 females) with normal naked eyesight or corrected visual acuity, were recruited, aged between 20 and 25 years old. No one suffered from color blindness, color weakness, or other diseases that may affect vision. Among them, 18 subjects were involved in the morning period, 24 in the afternoon period, and 27 in the evening period (with 9 subjects engaging in all three time periods). All subjects were randomly selected. They were students majoring in architecture, landscape architecture, or urban planning from the School of Architecture SCUT, and received certain compensation. Previous research showed that professionals in fields such as architecture, landscape planning, and arts tend to have stronger environmental observation and perception skills compared to others [34].

All subjects underwent a brief training session before the lightwalk, including (1) An overview of “lightscape” and the discipline, some specific types of lightscapes, and brief descriptions. (2) Clarifying the questionnaire content and indicators. On the day of every lightwalk, another round of focused explanations was given to highlight the essential guidelines for the lightwalking process and to avoid mutual influence.

The lightwalking process was consistently led by a researcher, as shown in Figure 2. When arriving at each pre-designated evaluation point, subjects were asked to look around for 30 s freely before filling out the electronic questionnaire for evaluation. After everyone had completed the questionnaire, the whole team collectively walked to the next evaluation site. Following the end of the lightwalk, a 5–10 min semi-structured interview was conducted for each subject, where participants were encouraged to freely describe any lightscapes that particularly caught their attention or attracted them during the lightwalk.

2.4. Data Analysis

The data for all three lightwalks were consolidated into one database. A total of 621 questionnaires were distributed, with 610 valid responses collected, as shown in

Table 3. Questionnaire information.

Lightwalk Name	1-MO	2-AF	3-EN
Date	16–18 October 2021	6 November 2021	16–18 October 2021
Time	10:00–11:30	16:00–17:30	19:00–20:30
Number of evaluation points	9	9	9
Number of participants	18	24	27
Distributed number	9 × 18 = 162	9 × 24 = 216	9 × 27 = 243
Valid number	159	209	242

Note: In the column headers, MO represents the morning lightwalk. AF represents the afternoon lightwalk. EN represents the evening lightwalk (author’s own work).

. Data statistical analysis and visualization were performed separately using SPSS 26.0 and MATLAB R2021a software. The Cronbach’s alpha reliability values of questionnaires all exceeded 0.8, indicating robust internal consistency in those data. The Kaiser–Meyer–Olkin (KMO) measure of sampling adequacy was calculated at 0.84 (>0.6); meanwhile, Bartlett’s test of sphericity was statistically significant (p < 0.001), indicating good structural validity of the data.

The data analysis of the three lightwalks is reported as follows:

• The perceived intensity and preference of each lightscape category, along with their temporal and spatial distributions, were calculated based on subjects’ subjective response data regarding the perception of different types of scenery. These pieces of information, to some extent, can reflect the spatiotemporal characteristics of the lightscape perception;
• Systematic cluster analysis based on the lightscape types and its overall perception evaluation results was performed, resulting in the delineation of distinct lightscape space groups on campus;
• Through a two-way analysis of variance (ANOVA), the perceptual differences between various types of lightscape and overall lightscape perception over time and space group factors were compared and analyzed;
• A mediation multiple regression (MMR) analysis, incorporating mediator variables for temporal and spatial factors, was conducted, so the relationship between lightscape types and overall lightscape perception is elucidated, along with the influence of time and space group factors on this relationship.

3. Results

3.1. Temporal and Spatial Characteristics of Campus Lightscape

3.1.1. Temporal Characteristics

The cumulative perceived intensity and preference of each lightscape category were calculated (Figure 3). The campus lightscape is dominated by meteorological, architectural, and biophilic lightscape types. The perceived intensity and preference proportions for each lightscape category during the lightwalk varied over time. One reason is that not all 27 categories of campus lightscape are present in all scenes throughout the day. Some categories occur only at certain time periods, such as sunset and with architecture decoration lighting.

The perceived intensity of meteorological lightscape is high in the morning and afternoon, with a notable increase in sunset and sunset glow categories as the afternoon progresses. In the evening, its perceived intensity decreases, with moonlight and skyglow becoming dominant. The perceived intensity of biophilic lightscape also declines in the evening, shifting from plant shadows in the morning and afternoon to landscape lighting in the evening. However, the temporal changes in architectural and traffic lightscape exhibit an opposing trend: in the morning and afternoon, the higher perceived categories of architectural lightscape shift from building shadows during the day to decorative lighting and lights escaping from the windows in the evening; for traffic lightscapes, the higher perception of lightscape categories change from car window reflections to the street lighting from morning to the evening. There is only a slight decrease in the perceived intensity of water lightscapes over time.

Compared to other lightscape types, the preference for meteorological lightscape increases in the afternoon and evening, differing significantly from the pattern of perceived intensity. It is interesting that meteorological categories that appear at specific times, such as sunset, generally receive higher preference ratings.

3.1.2. Spatial Characteristics

The Inverse Distance Weighting (IDW) method of the ArcGIS platform was used in visualizing the spatial distribution patterns of perceived intensity and the preference of the five types of lightscape, as shown in Figure 4. Each image represents a different lightscape type listed in Table 1. As shown in the figures, for the two types of meteorological and traffic lightscape, the distribution with strong perceived intensity and high preference lightscape is scattered; for the other three lightscape types, the distribution is clustered around evaluation points.

The water lightscape is mainly distributed in squares and sidewalks near artificial lakes (#3, #4, #6, and #7); the architectural lightscape is mainly distributed in areas around office buildings or teaching buildings (#1, #5, #8, and #9); and the biophilic lightscape is mainly distributed in areas with well-configurated landscapes (#6, #8, and #9).

3.2. Effect of Time and Space Group Factors on Lightscape Perception

3.2.1. Evaluation Point Types Based on Lightscape Perception

The preceding Section 3.1 describes how the campus lightscapes vary with time and site. Given the complexity of spatial distribution differences therein, the Hierarchical Cluster Analysis (HCA) is employed for explanation here. HCA is a common method used for identifying significant features and patterns in landscapes [35]. This method categorizes evaluation points into higher-level groups with certain similarities, facilitating the formation of spatial groups of a landscape [36]. In this study, HCA was based on the between-group linkage and average Euclidean distances. All data were collected during the lightwalking experiments mentioned earlier.

The dendrogram of the cluster result is shown in Figure 5. The nine total evaluation points in these lightwalks were categorized into three space groups: (1) Group A (educational areas) is dominated by meteorological and architectural lightscape, with two distinctive Lingnan-style department office buildings (#1, #9), three modern teaching buildings (#2, #5, and #8), and their adjacent square spaces; (2) Group B (activity areas) is dominated by meteorological and water lightscapes, containing two waterside pedestrian pathways (#3 and #7) and one landscape square (#4); (3) Group C (green-shaded area) is dominated by water and biophilic lightscapes, featuring a green-shaded area surrounded by an artificial lake (#6).

3.2.2. The Effects of Time and Space Group Factors and Their Interaction on Lightscape Type Perception

A two-way ANOVA was further performed based on the results of the cluster space groups above.

Table 4. Effects of space group, time factor, and their interaction on perceived intensity and preference of lightscape types.

Lightscape Type	Dependent Variables	Main Effects	SS	df	MS	F	p	η2
Meteorological	Perceived Intensity	Space group	180.17	2	90.08	18.62	<0.01	0.06
		Time	499.23	2	249.61	51.60	<0.01	0.15
		Interaction	57.97	4	14.49	3.00	<0.05	0.02
	Preference	Space group	51.52	2	25.76	10.45	<0.01	0.03
		Time	73.66	2	36.83	14.94	<0.01	0.05
		Interaction	34.23	4	8.56	3.47	<0.05	0.02
Water	Perceived Intensity	Space group	2562.44	2	1281.22	489.38	<0.01	0.62
		Time	38.35	2	19.18	7.32	<0.01	0.02
		Interaction	17.52	4	4.38	1.67	0.15	0.01
	Preference	Space group	1775.24	2	887.62	511.98	<0.01	0.63
		Time	18.47	2	9.23	5.33	<0.05	0.02
		Interaction	1.99	4	0.50	0.29	0.89	0.00
Architectural	Perceived Intensity	Space group	529.77	2	264.88	84.32	<0.01	0.22
		Time	104.26	2	52.13	16.59	<0.01	0.05
		Interaction	91.78	4	22.95	7.30	<0.01	0.05
	Preference	Space group	248.78	2	124.39	72.06	<0.01	0.19
		Time	58.11	2	29.06	16.83	<0.01	0.05
		Interaction	47.01	4	11.75	6.81	<0.01	0.04
Biophilic	Perceived Intensity	Space group	136.72	2	68.36	14.61	<0.01	0.05
		Time	190.27	2	95.14	20.33	<0.01	0.06
		Interaction	18.25	4	4.56	0.98	0.42	0.01
	Preference	Space group	47.15	2	23.58	7.14	<0.01	0.02
		Time	118.67	2	59.34	17.96	<0.01	0.06
		Interaction	12.79	4	3.20	0.97	0.42	0.01
Traffic	Perceived Intensity	Space group	59.91	2	29.96	6.81	<0.01	0.02
		Time	1107.70	2	553.85	125.86	<0.01	0.30
		Interaction	18.23	4	4.56	1.04	0.39	0.01
	Preference	Space group	14.51	2	7.26	4.21	<0.05	0.01
		Time	365.41	2	182.70	106.12	<0.01	0.26
		Interaction	7.13	4	1.78	1.04	0.39	0.01

SS: sum of squares, representing the total variation in the data; df: degrees of freedom, indicating the number of independent values that can vary; MS: Mean Square, the average of the sum of squares divided by the degrees of freedom; F: F-Statistic; p: p-value; η²: Eta Squared, representing the proportion of the total variance explained by a factor (effect size) (author’s own work).

presents the main effects of space group factors, time factors, and their interaction on the perceived intensity and preference of lightscape types. The results indicate that both time (morning, afternoon, and evening) and space groups (Groups A, B, and C) exerted significant effects on the perceived intensity and preference of all five lightscape types. For meteorological and architectural lightscape, there are statistically significant effects from the interaction between time and space group factors.

Further pairwise comparisons were conducted to reveal the specific characteristics of time and space group factors in lightscape types (

Table 5. Pairwise comparisons of perceived intensity and preference of lightscape types under time and space group factors.

Main Effects	Dependent Variables	Lightscape Type	A-B	A-C	B-C
Space group factor	Perceived Intensity	Meteorological	0.11	1.78 *	1.66 *
		Water	−4.10 *	−4.40 *	−0.3
		Architectural	0.99 *	3.00 *	2.01 *
		Biophilic	0.74 *	−0.80 *	−1.54 *
		Traffic	0.29	1.02 *	0.74 *
	Preference	Meteorological	−0.14 *	0.86 *	1.00 *
		Water	−3.50 *	−3.43 *	0.07
		Architectural	0.43 *	2.11 *	1.69 *
		Biophilic	0.40 *	−0.52 *	−0.92 *
		Traffic	0.14	0.50 *	0.37 *
Main Effects	Dependent Variables	Lightscape type	MO-AF	MO-EV	AF-EV
Time factor	Perceived Intensity	Meteorological	−1.41 *	1.19 *	2.60 *
		Water	0.57 *	0.77 *	0.2
		Architectural	0.11	−0.97 *	−1.09 *
		Biophilic	0.52	1.64 *	1.12 *
		Traffic	0.53	−3.07 *	−3.60 *
	Preference	Meteorological	−1.05 *	−0.31 *	0.74 *
		Water	0.36 *	0.54 *	0.18
		Architectural	0.06	−0.74 *	−0.80 *
		Biophilic	0.46	1.31 *	0.85 *
		Traffic	0.12	−1.88 *	−2.00 *

* p < 0.05. A—Group A. B—Group B. C—Group C. MO—morning. AF—afternoon. EV—evening. Note: The values in the table represent the mean differences between pairwise comparisons (author’s own work).

). On the one hand, the clustering division (Figure 5) shows further insight into how the space group factors influence the perception of lightscape types. Specifically, the perceived intensity and preference of water lightscapes differ only between Groups A and B and Groups A and C, while differences are noted between Groups A and C and Groups B and C for traffic lightscapes.

The perceived intensity and preference of water lightscape exhibit significant differences between morning and afternoon/night. The perceived intensity and preference of architectural, biophilic, and traffic lightscape show significant differences between morning/afternoon and night. For meteorological lightscapes, there are significant differences in perceived intensity and preference across all groups of three time periods.

3.2.3. Effects of Time and Space Group Factors and Their Interaction on Overall Lightscape Perception

The 23 descriptive adjectives on overall lightscape perception, derived from principal component analysis (PCA), were filtered by gradually removing factors with cross-loadings exceeding 0.4. Then, four principal components of lightscape perception (F1, F2, F3, and F4, total including 17 descriptive adjectives), as shown in

Table 6. Results of the principal component analysis on overall lightscape perception (N = 610).

Item	F1	F2	F3	F4
Explained variance (%)	28.2	15.32	7.79	7.52
Pleasant–unpleasant	0.83
Interesting–boring	0.81
Satisfied–unsatisfied	0.79
Comfortable–uncomfortable	0.73
Impressive–unimpressive	0.67
Bright–dim		0.82
Direct–indirect		0.73
Glaring–soft		0.69
Warm–cool		0.60
Colorful–uncolorful		0.59
Safe–dangerous			0.80
Social–non-social			0.68
Ordered–disordered			0.59
Harmonious–discordant			0.59
Traditional–modern				0.87
Natural–artificial				0.65
Cultured–uncultured				0.47
Even distributed brightness–uneven distributed brightness	Cross-loadings exceeding 0.4 (stepwise exclusion)
Seasonal–seasonless
Vibrant–dull
Dynamic–static
Rhythmic–rhythmless
Beautiful–ugly

Note: Only structural coefficients above 0.40 are displayed. F1: emotional. F2: luminous. F3: eventful. F4: cultural (author’s own work).

, with a cumulative contribution rate of 58.83% of the overall variance, were extracted. These four aspects were going to be used to comprehensively investigate the dimensional characteristics of the overall lightscape perception on campus.

A two-way ANOVA was utilized to examine the principal effects of time and space group factors, along with their interaction, on the overall lightscape perception, as shown in

Table 7. Effects of space group, time factor, and their interaction on the overall lightscape perception.

Dependent Variables	Main Effects	SS	df	MS	F	p	η2
Emotional	Space group	67.13	2.00	33.56	38.06	<0.01	0.11
	Time	7.46	2.00	3.73	4.23	<0.05	0.01
	Interaction	9.54	4.00	2.39	2.71	<0.05	0.02
Luminous	Space group	96.33	2.00	48.16	64.54	<0.01	0.18
	Time	27.49	2.00	13.75	18.42	<0.01	0.06
	Interaction	21.04	4.00	5.26	7.05	<0.01	0.04
Eventful	Space group	88.75	2.00	44.38	52.21	<0.01	0.15
	Time	2.11	2.00	1.06	1.24	0.29	0.00
	Interaction	7.87	4.00	1.97	2.31	0.06	0.02
Cultural	Space group	52.26	2.00	26.13	28.85	<0.01	0.09
	Time	3.34	2.00	1.67	1.85	0.16	0.01
	Interaction	2.94	4.00	0.73	0.81	0.52	0.01

SS: sum of squares, representing the total variation in the data; df: degrees of freedom, indicating the number of independent values that can vary; MS: Mean Square, the average of the sum of squares divided by the degrees of freedom; F: F-Statistic; p: p-value; η²: Eta Squared, representing the proportion of the total variance explained by a factor (effect size) (author’s own work).

. The time (morning, afternoon, and evening) factor only exerts a significant effect on the emotional and luminous principal components, while the space group factor significantly influences all four. The interaction between time and space groups was also significant for the emotional and luminous principal components. Overall, the space group factors’ effect on the overall lightscape perception seemed to be more pronounced compared to the time factor.

Further, pairwise comparisons are used to analyze specific characteristics of time and space group factors in the principal components of overall lightscape perception (

Table 8. Pairwise comparisons for overall lightscape perception under time and space group factors.

Main Effects	Dependent Variables	A-B	A-C	B-C	Main Effects	Dependent Variables	MO-AF	MO-EV	AF-EV
Space group factor	Emotional	−0.32 *	−1.08 *	−0.76 *	Time factor	Emotional	0.23	0.34 *	0.11
	Luminous	−0.57 *	0.76 *	1.33 *		Luminous	−0.27 *	0.34 *	0.61 *
	Eventful	0.83 *	0.59 *	−0.24		Eventful	—	—	—
	Cultural	0.45 *	−0.50 *	−0.95 *		Cultural	—	—	—

* p < 0.05. Note: The values in the table represent the mean differences between pairwise comparisons. A—Group A. B—Group B. C—Group C. MO—morning. AF—afternoon. EV—evening (author’s own work).

). Under the effect of space group factors, emotional, luminous, and cultural lightscape evaluation exhibited significant differences between the pairs of three space groups; eventful feelings only showed a significant difference between A-B and A-C groups, with Group A demonstrating higher scores by 0.83 compared to Groups B and 0.59 to C, manifesting that Group A brings more positive safety, social, and harmonious feelings. Regarding the time factors, luminous feelings displayed significant differences between every pair of three space groups, whereas emotional evaluation only varied between morning and evening.

3.3. Perception Models of Campus Lightscape

3.3.1. The Effect of Type Perception on Overall Lightscape Perception

The mediation multiple regression analysis was applied to explore the impact of time and space group factors on the relationship between the perception of lightscape types. The dependent variables being analyzed were lightscapes’ emotional, luminous, eventful, and cultural factors, while the independent variables were the perception intensity and preference of five lightscape types. For all data, Durbin–Watson (D-W) test values ranged from 1.78 to 1.96 (≈2), ensuring data independence; the normal distribution of standardized residuals and the minimal effect of multicollinearity among independent variables (VIF < 10) were confirmed. All models were statistically significant (p < 0.01), with an R² value exceeding 0.2, demonstrating that the independent variables could explain more than 20% of the variance in the dependent variables.

As illustrated in

Table 9. Result of the hierarchical regression model on factors affecting overall lightscape perception.

		(a)		(b)		(c)		(d)
		Emotional		Luminous		Eventful		Cultural
		I	II	I	II	I	II	I	II
	(constant)	0.090 (0.453)	−0.149 (−0.689)	−0.761 ** (−3.796)	−0.018 (−0.086)	−0.151 (−0.758)	0.022 (0.106)	−0.130 (−0.600)	−0.025 (−0.113)
Lightscape type perception	Meteorological a	−0.113 ** (−4.929)	−0.119 ** (−4.855)	0.113 ** (4.893)	0.024 (1.016)	−0.005 (−0.222)	−0.009 (−0.400)	−0.015 (−0.603)	−0.015 (−0.596)
	Water a	−0.049 (−1.208)	−0.091 * (−2.290)	−0.033 (−0.793)	−0.026 (−0.676)	−0.130 ** (−3.173)	−0.096 * (−2.390)	−0.152 ** (−3.396)	−0.120 ** (−2.744)
	Architectural a	−0.123 ** (−3.976)	−0.094 ** (−3.111)	−0.033 (−1.044)	−0.067 * (−2.333)	0.008 (0.257)	−0.007 (−0.233)	0.002 (0.055)	−0.009 (−0.269)
	Biophilic a	0.029 (0.962)	0.023 (0.777)	−0.017 (−0.544)	−0.029 (−1.052)	0.032 (1.058)	0.023 (0.800)	0.052 (1.566)	0.043 (1.341)
	Traffic a	−0.125 ** (−4.471)	−0.095 ** (−3.414)	0.071 * (2.526)	0.080 ** (3.035)	−0.040 (−1.419)	−0.040 (−1.484)	−0.032 (−1.031)	−0.029 (−0.978)
	Meteorological b	0.107 ** (3.211)	0.145 ** (4.370)	−0.040 (−1.177)	0.001 (0.037)	−0.007 (−0.221)	−0.005 (−0.160)	−0.007 (−0.190)	−0.004 (−0.102)
	Water b	0.124 ** (2.587)	0.074 (1.528)	0.133 ** (2.749)	0.081 (1.738)	0.048 (0.993)	0.153 ** (3.141)	0.058 (1.101)	0.166 ** (3.118)
	Architectural b	0.136 ** (3.407)	0.174 ** (4.452)	0.073 (1.797)	0.032 (0.858)	0.101 * (2.509)	0.114 ** (2.919)	0.109 * (2.475)	0.129 ** (3.010)
	Biophilic b	0.002 (0.053)	−0.009 (−0.254)	0.055 (1.555)	0.058 (1.792)	0.017 (0.488)	0.015 (0.449)	0.016 (0.409)	0.013 (0.344)
	Traffic b	0.140 ** (3.129)	0.155 ** (3.563)	−0.102 * (−2.248)	−0.051 (−1.230)	0.002 (0.034)	−0.002 (−0.055)	−0.016 (−0.317)	−0.021 (−0.451)
Time	AF	—	−0.156 (−1.583)	—	−0.013 (−0.134)	—	—	—	—
	EV	—	−0.431 ** (−3.629)	—	−0.629 ** (−5.538)	—	—	—	—
Space group	B	—	0.402 ** (3.126)	—	0.393 ** (3.194)	—	−0.901 ** (−7.033)	—	−0.927 ** (−6.618)
	C	—	1.152 ** (6.693)	—	−0.870 ** (−5.291)	—	−0.556 ** (−3.249)	—	−0.418 * (−2.235)
N		610	610	610	610	610	610	610	610
R2		0.133	0.205	0.112	0.274	0.126	0.195	0.135	0.2
Adjusted R2		0.119	0.186	0.097	0.257	0.112	0.179	0.121	0.184
F		9.189 **	10.956 **	7.534 **	16.051 **	8.658 **	10.327 **	9.349 **	12.420 **

* p < 0.05. ** p < 0.01. ^a Perceived Intensity. ^b Preference. Note: The values in the table are unstandardized regression coefficients, with t-values in parentheses. B—Group B. C—Group C. AF—afternoon. EV—evening (author’s own work).

, the perceived intensity of most lightscape types negatively affects the overall lightscape perception, whereas preference has a positive effect. The following points further elaborate on these findings:

• When the perceived intensity of meteorological, architectural, and traffic lightscapes increases, emotional evaluations tend to decrease. However, an increase in preference for these lightscape types is associated with a positive enhancement in emotional evaluations.
• An increase in the perceived intensity of architectural lightscapes is associated with a decrease in luminous evaluations. Meanwhile, an increase in the perceived intensity of traffic lightscape leads to an increase in luminous evaluations.
• As the perceived intensity of the water lightscape increases, eventful evaluation decreases. Nonetheless, when the preference for water and architectural lightscape increases, eventful evaluation also rises.
• An increase in the perceived intensity of water lightscape results in a decrease in cultural evaluation. However, an increase in preference for water and architectural lightscapes leads to an increase in cultural evaluations.

3.3.2. Mediating Effects of Time and Space Group Factors on Lightscape Perception Models

With the inclusion of time and space group dummy variables in the models, there was a significant increase in R² values for all models, so the significant effects of time and space group factors on overall lightscape perception are proved.

Table 10. Mediation effects of time and space group factors on the relationship between lightscape types and overall lightscape perception.

Mediator	Dependent Variable	Independent Variable	Test Results	Total Effect (c)	Indirect Effect (a × b)	Direct Effect (c′)	Proportion of Effects
EV	Emotional	Meteorological a	Masking effect	−0.113	0.041	−0.119	34.49%
		Meteorological b	Masking effect	0.107	−0.034	0.145	23.34%
		Traffic b	Masking effect	0.14	−0.025	0.155	16.31%
	Luminous	Traffic a	Masking effect	0.071	−0.031	0.08	38.99%
B	Eventful	Water b	Masking effect	0.048	−0.105	0.153	68.59%
		Architectural b	Masking effect	0.101	−0.037	0.114	32.05%
C	Emotional	Architectural b	Masking effect	0.136	−0.048	0.174	27.84%
	Luminous	Architectural a	Masking effect	−0.033	0.027	−0.067	39.72%
EV	Luminous	Meteorological a	Primary mediation effect	0.113	0.06	0.024	100%
		Traffic b	Primary mediation effect	−0.102	−0.037	−0.051	100%
B	Emotional	Water b	Primary mediation effect	0.124	0.047	0.074	100%
	Luminous	Water b	Primary mediation effect	0.133	0.046	0.081	100%
	Cultural	Water b	Primary mediation effect	−0.08	−0.074	−0.007	100%
		Architectural b	Primary mediation effect	0.026	−0.026	0.067	100%
C	Luminous	Meteorological a	Primary mediation effect	0.113	0.025	0.024	100%
	Cultural	Architectural b	Primary mediation effect	0.026	−0.015	0.067	100%
EV	Emotional	Traffic a	Partial mediation effect	−0.125	−0.021	−0.095	17.21%
B	Emotional	Architectural b	Partial mediation effect	0.136	0.016	0.174	11.97%
C	Emotional	Meteorological a	Partial mediation effect	−0.113	−0.034	−0.119	29.70%
		Architectural a	Partial mediation effect	−0.123	−0.035	−0.094	28.75%
		Traffic a	Partial mediation effect	−0.125	−0.023	−0.095	18.10%
	Luminous	Traffic a	Partial mediation effect	0.071	0.017	0.08	23.92%
	Eventful	Architectural b	Partial mediation effect	0.101	0.023	0.114	23.11%

^a Perceived Intensity. ^b Preference. B—Group B. C—Group C. EV—evening. Note: Percentile Bootstrap CI is used to test significance. Proportion of Effects Formulae: |a × b/c′| denotes the masking effect. a × b/c indicates a partial-mediation effect. Data results showing no significant relationship between the independent and dependent variables are not included in this table (author’s own work).

shows that the evening period has the most significant effect on the relationship between meteorological and traffic lightscape with emotional and luminous evaluation. The spatial characteristics of Group B exert the greatest effect on the relationship between water and architectural lightscape with overall lightscape perception; the spatial characteristics of Group C have the most significant influence on the relationship between the architectural lightscape and overall lightscape perception.

4. Discussion

4.1. Composition Characteristics of Campus Lightscape

This study utilizes lightscapes fitting into 27 categories, which are the lightscapes that most subjects found memorable. Though not all the categories are always observable at any site point and at any time, they still exhibit the diversity and complexity of lightscapes in outdoor campus spaces and the fact that lightscapes have distinct temporal and spatial characteristics.

In this study, meteorological, architectural, and biophilic lightscapes are the predominant lightscape types in the outdoor campus spaces of the Wushan Campus of SCUT. As illustrated in Figure 3, the primary lightscapes perceived include meteorological lightscape from the sky (dominated by daylight, cloud shadows, sunsets, and moonlight), architectural lightscape from artificial architecture (dominated by building shadows, building facade reflection, and architecture decoration lighting), and biophilic lightscape from bio-friendly designs (dominated by plants shadow, light and shadow created by people, animals and their movements, and landscape decoration lighting).

The prominence of architectural and biophilic lightscape notes that buildings and active populations shape the diverse blending of landscapes on university campuses. The campus landscape not only includes artificial and natural environments but also combines cultural landscapes created by human activities. Moreover, this study indicates that distinct and easily recognizable landscape structures on campus may contribute to rich outdoor lightscapes.

4.2. Spatial and Temporal Characteristics of Lightscape

This study investigates the effect of time and space group factors on lightscape type perception and overall lightscape perception using hierarchical clustering analysis (Figure 5), principal component analysis (Table 6), and two-way ANOVA (Table 4 and Table 7). It indicates that time and space group factors significantly affect the perception of lightscape types in outdoor campus spaces (as demonstrated in Table 5). It also reveals that the effect of space group factors on overall lightscape perception exceeds that of time factors (as demonstrated in Table 8). Space group factors affect all four dimensions of the overall lightscape perception, whereas time factors mainly influence two of the evaluation dimensions, emotional and luminous.

The fact that lightscape categories change over time (see Figure 3 and Table 5) also explains that the temporal differences in lightscape types’ perception are related to the dominant lightscape categories and the composition, driven by changes in natural light, transition of light sources from day to night, and human activity patterns. The perceived intensity of meteorological lightscape varies throughout the day, being higher in the morning and afternoon and lower at night. This variation indicates that variations influenced by dominant lightscape categories are attributed to the high landscape attraction of specific meteorological lightscape moments (such as sunsets and sunset glow) [5,37].

Other findings highlight that the significant differences in the perception of water, architectural, biophilic, and traffic lightscapes between one time period and the other two are due to the changes in the composition of lightscape categories. The results indicate that sunlight in the morning enhances the visual effects of water lightscapes, and the enhancement of light and shadow effects among vegetation and plant structures varies with daylight [38]; thereby, the presence of water and biophilic experiences is elevated.

A different situation is the perceived intensity and preference for architectural and traffic lightscapes, as primarily formed by artificial light sources, which peak in the evening period. This appearance is not only caused by the difference of main light sources but also closely related to the activity patterns of people inside the campus. At night-time, the increase in lighting, coupled with the overall reduction in natural environment brightness and the decreased visibility of natural lightscapes, makes architectural and traffic lightscapes more easily identifiable and experienced.

Visualizing the spatial distribution of lightscape types (Figure 4) and conducting pairwise comparisons of the space group factor (Table 5) reveals that the space of the perceptible lightscape is closely associated with the spatial structure of the sites, primary functions, and key visual cues. The results are attributed to the spatial characteristics of Group A, which is dominated by meteorological and architectural lightscapes and is situated away from the campus’s artificial lake, thus having less direct interaction with the water lightscape; Group C, dominated by water and biophilic lightscape, involves fewer traffic-related factors. This suggests that differences between the two lightscape types are associated with their degree of dominance in the site. The perceived intensity and preference for biophilic and architectural lightscape manifested significant differences across all groups, indicating that perceived intensity and preference are related to the unique functional characteristics of the sites [23,39].

Moreover, meteorological lightscape perception tends to decrease in areas concentrated with a biophilic lightscape, possibly due to the reduced direct sunlight by dense plant canopies [40,41].

4.3. Effects of Time and Space Factors on the Relationship between Lightscape Types and Lightscape Overall Perception

The mediation effect test (Table 10) indicates that the temporal characteristics of the evening period display a masking effect in the relationships between the meteorological lightscape and emotional evaluation, traffic lightscape preference and emotional evaluation, as well as traffic lightscape perceived intensity and luminous evaluation. This suggests that mediator variables may neutralize the direct connections among those variables [42]. Similarly, the spatial characteristics of Group B exhibit a masking effect in the relationships between water and architectural lightscape preferences with eventful evaluation, while the spatial characteristics of Group C show a masking effect in the relationships between architectural lightscape preference and emotional evaluation and architectural lightscape perceived intensity and luminous evaluation.

In contrast, temporal characteristics of the evening period display a partial-mediation effect in the relationship between traffic lightscape perceived intensity and emotional evaluation, indicating that mediator variables enhance this relationship. The spatial characteristics of Group B exhibit a partial-mediation effect between architectural lightscape preference and emotional evaluation. The spatial characteristics of Group C show partial mediation effects in the relationships between meteorological, architectural, and traffic lightscape perceived intensity and emotional evaluation, as well as between traffic lightscape perceived intensity and luminous evaluation and between architectural lightscape preference and eventful evaluation.

When discussing the mediating role of evening temporal characteristics, the effect of the meteorological lightscape’s perceived intensity and traffic lightscape preference on luminous evaluation are primary mediation effects, highlighting the mediator variables as key pathways in this relationship.

When discussing the mediating role of spatial characteristics, the spatial characteristics of Group B mediate the effects of water lightscape preference on eventful and luminous evaluations, as well as the effects of water and architectural lightscape preferences on cultural evaluation; the spatial characteristics of Group C mediate the effects of the meteorological lightscape’s perceived intensity and architectural lightscape preference on luminous and cultural evaluations, both showing as primary mediation effects.

However, for the relationship between the perceived intensity of the water lightscape and emotional, eventful, and cultural evaluation, the mediating effect of time and space group factors is not significant, indicating that not all relationships between variables are influenced by mediation factors.

Based on the results of mediation multiple regression analysis (Table 9 and Table 10), this study further explores the impact of time and space group factors on the relationship between lightscape types and overall lightscape perception on university campuses, as well as their optimization strategies.

• This field study on the Wushan Campus shows that the perceived intensity and preference of lightscape types significantly impact the evaluation of the overall lightscape perception. When the perceived intensity of meteorological, water, architectural, and traffic lightscapes increases, lightscape evaluations of emotional, eventful, and cultural aspects tend to decrease. However, at specific points and at certain times, an increase in preference for these lightscape categories can positively enhance the overall lightscape perception. Previous research has indicated that the landscape content is a crucial factor influencing people’s perceptions and preferences [43,44], which has been validated in the study of lightscape perception.
• The time factor in the evening significantly affects the relationship between meteorological and traffic lightscapes and the overall lightscape perception. On the one hand, the evening condition exhibits a masking effect on the relationship between meteorological and traffic lightscapes and emotional and luminous aspects, indicating that the positive impacts from the lightscapes do not lead to stronger positive emotional experiences or greater luminous perceptions [45]. So, optimizing these two types may not improve the lightscape experience in the evening; reducing the perceived intensity or introducing preferred lightscape categories also may not effectively enhance the lightscape experience. On the other hand, the time factor does not significantly affect the relationship between water and architectural lightscapes and overall lightscape perception in the evening, indicating that these two lightscape types still play an important role in overall perception during the evening time. Optimizing the design of water and architectural lightscapes may be an effective way to enhance evening lightscape experiences. For example, reducing unfavorable architectural decorative lighting or water reflections or optimizing the illumination of lake waves and distant building outlines can promote positive emotions and soft visual experiences, consistent with research findings on better psychological responses in dark environments [26,46,47].
• Space group factors significantly influence the relationship between meteorological, water, architectural, and traffic lightscapes and overall lightscape perception. Specifically, the spatial characteristics of Group B exhibit a masking effect on the relationship between the preference for water and architectural lightscapes and eventful evaluation while acting as a primary mediator in influencing the other three overall lightscape perception indicators (emotional, luminous, and cultural aspects). This suggests that the spatial characteristics of campus waterside squares and pedestrian pathways (Group B) do not significantly enhance eventful evaluations, but these characteristics play a decisive role in improving the evaluations of emotional, luminous, and cultural aspects, consistent with findings from existing research [48]. Regarding the spatial characteristics of Group C, they show a partial-mediation effect on the relationship between meteorological, architectural, and traffic lightscapes and the evaluations of emotional, luminous, and eventful aspects. This indicates that inside green-shaded areas (Group C), the relationship between these lightscape types and overall lightscape perception is strengthened. This may be because green-shaded spaces possess higher visual mystery and complexity, enhancing people’s lightscape preference [49,50]. Therefore, it is recommended to increase green-shaded spaces in more areas on campus to strengthen the connection between lightscape types and overall lightscape perception, thereby enhancing the quality of the lightscape experience; meanwhile, using balanced design, focusing on optimizing water and architectural lightscapes in waterside squares and pathways can enhance the positive effects on emotional, luminous, and cultural aspects.

4.4. Limitations and Further Research

This study has certain limitations. All subjects are somewhat monotonous in demographic, social, and behavioral characteristics; when subjects from a wider range of individual socio-cultural backgrounds are used in our later study [51,52], the universal principles among the three “lightscape-person-environment” elements can be further investigated.

Despite its limitations, the significance of this study lies in the exploration of the temporal and spatial characteristics of lightscape perception using several lightwalks under different spatiality and temporality. Additionally, it investigates the relationships between lightscape categories and overall lightscape perception, as well as the mediation effect of time and space factors. It contributes to a broader understanding of the temporality and spatiality of lightscape perception.

5. Conclusions

This study is based on three lightwalks in separately three time periods. Interviews after walks reveal that subjects spontaneously compared details of the lightscapes across different times and perspectives, thereby gaining a deeper understanding of a “contextual” landscape. This study demonstrates a significant advantage of the lightwalk method in enhancing subjects’ recognition and perception of lightscape [53,54,55].

This study focuses on how time and space factors in outdoor university campus spaces influence lightscape perception. The specific conclusions are as follows:

• Campus lightscapes are primarily composed of meteorological, artificial architectural, and biophilic elements, having recognizable landscape structures and visual cues.
• Temporal changes, including changes in natural light, light sources transition from day to night, and human activity patterns, all influence lightscape perception. Furthermore, the functional characteristics, structural features, and key visual cues of the site play a crucial role in the spatial variations of lightscape perception.
• The perceived intensity and preference of lightscape types significantly affect overall lightscape perception. Specifically, when the perceived intensity of meteorological, water, architectural, and traffic lightscapes increase, evaluations of emotional, eventful, and cultural aspects generally become lower. However, an increase in preference for these lightscape categories can positively enhance the overall lightscape perception at specific times and locations.
• Temporal and spatial factors have an important influence on the relationship between lightscape types and overall lightscape perception. Temporal factors, particularly in the evening period, significantly impact the relationship between meteorological, traffic lightscapes, and overall lightscape perception. The evening condition tends to mask the positive impacts of these lightscape types on emotional and luminous aspects; thus, simply increasing the intensity of these lightscapes may not improve the evening lightscape experience. And optimizing the design of water and architectural lightscapes in the evening may significantly improve the lightscape experience.
• In non-green-shaded areas such as educational areas, squares, and pathways, the perceived intensity and preference for water and architectural lightscape show noticeable variations. Green-shaded areas, however, always enhance the relationship between meteorological, architectural, and traffic lightscape types and emotional, luminous, and eventful evaluations. More green-shaded spaces on campus are recommended to strengthen the connection between lightscape types and overall lightscape perception, thereby enhancing the quality of the lightscape experience. Balanced design focusing on water and architectural lightscape in waterside squares and pathways can further enhance the positive effects on emotional, luminous, and cultural aspects of the lightscape.

The results above remind us of the significance of unity in creating a sustainable campus lightscape with a sustainable environment. Perceptual and experiential research based on the unique temporal and spatial characteristics of the lightscapes exemplifies the broader goal of constructing a sustainable habitat environment. This study provides a new insight into the temporal and spatial characteristics of lightscape perception, offering practical guidance for campus lightscape design and management; it also pioneers the research of spatial and temporal factors of lightscape in outdoor spaces of university campuses.