Evolution of Hexi Corridor architectural spaces under climate change

Abstract

This study examines how the traditional architecture of China’s Hexi Corridor adapted to its harsh arid, cold, and windy climate through thick earthen-wood composite walls, compact layouts, and enclosed courtyards. These elements not only reflect advanced vernacular construction techniques but also offer insights into past climate patterns and cultural exchanges along the Silk Road. By integrating the Mann-Kendall trend test with meteorological records, geographical analysis, and architectural typology, the study explores the evolving relationship between architectural development and climatic fluctuations from the Wei-Jin (220–420 CE) to the Ming-Qing (1368–1912 CE) periods. The findings provide quantitative evidence of how traditional structures adapted to environmental changes, offering valuable perspectives for both architectural heritage conservation and historical climatology research in the context of Silk Road studies.

Introduction

The Hexi Corridor, a vital section of the ancient Silk Road, stretches approximately 1000 km across northwestern Gansu Province, China¹. Flanked by the Qilian Mountains to the south and the Heli-Longshou Mountains to the north, this strategic passage connected China’s Central Plains with the Western Regions, serving as a crucial hub for cultural exchange and trade². The traditional architecture of Hexi Corridor demonstrates sophisticated climate-responsive design. Buildings typically adopt south-facing orientations to optimize winter solar gain while minimizing summer heat exposure³. Such as dome structures that enhance natural ventilation and thermal comfort. Religious structures like the Mogao Grottoes exemplify this adaptive approach. Similarly, defensive structures such as Jiayuguan’s fortifications feature thick walls that mitigate temperature extremes while providing protection⁴. These designs show a deep knowledge of environmental problems. They successfully balance human requirements with natural conditions. The historical designs offer valuable insights for contemporary climate-adaptive architecture (Fig. 1).

Fig. 1

Location information of Hexi Corridor and existing traditional architectural environment.

This study selects temperature and precipitation as the key climatic indicators for assessing the impact of climate change on architectural spatial forms, owing to their direct relevance and broad applicability in building design. Temperature directly shapes thermal insulation, ventilation, and energy usage strategies, while precipitation governs drainage systems, moisture protection, and roof design. Both factors play fundamental roles in influencing spatial layouts. In comparison, other climatic elements—such as air pressure, wind speed, and solar radiation—are either indirectly expressed through temperature and precipitation (for instance, wind load is often treated as a fixed parameter in structural standards) or limited to specific regional contexts (such as high-wind corridors or high-insolation areas). Moreover, temperature and precipitation provide consistent, quantifiable, and widely available data essential for analyzing long-term climate trends. Other variables, like air pressure—which typically shows minimal variation—or normative structural responses to wind, contribute less significantly to the distinct evolution of architectural spatial forms.

Research on the climate adaptability of traditional architecture in the Hexi Corridor faces several challenges. First, many architectural sites are unevenly preserved, with damage caused by weathering, desertification, and human activities. This limits the ability to conduct a comprehensive analysis of how building spaces respond to climate. Additionally, studying climate adaptation requires an interdisciplinary approach that combines architecture, meteorology, and environmental science⁵. However, the lack of effective collaborative frameworks often restricts the depth of such research. While existing studies tend to focus on specific historical periods, the full scope of climatic variations over the millennia in the Hexi Corridor remains underexplored. This study aims to fill that gap by examining the interactions between climate and architecture from the Wei-Jin period through the late Qing and early Republican eras (3rd to 20th centuries). Using integrated meteorological, geographical, and architectural theories, the research seeks to enhance scholarly understanding while also developing new interdisciplinary methods for studying architectural heritage along the Silk Road.

Methods

Research area selection

This study centers on the Hexi Corridor because of its unique geographical and climatic conditions, which gave rise to distinctive architectural adaptations. Located between mountain ranges, the corridor receives vital snowmelt from the Qilian Mountains that supports oasis cities such as Zhangye and Jiuquan, even as deserts surround them⁶. The stark contrast between dry desert and fertile oasis, along with limited inland river resources, encouraged the development of specialized irrigation-based agriculture and distinctive settlement patterns. The chosen research period—from the Wei-Jin to the Qing Dynasty (3rd to 19th centuries)—covers key phases in both architectural and climatic history. Architecturally, it includes the peak of Chinese spatial design during the Tang and Song Dynasties, as well as its later decline. Climatically, it spans both cold intervals, such as the Little Ice Age during the Wei-Jin and Ming-Qing periods, and warmer phases like the Sui-Tang era⁷. Over these 1600 years, major climatic and political changes significantly shaped the corridor’s architectural development.

Situated along a vital segment of the Silk Road, the Hexi Corridor developed a distinctive cultural identity. Its geographical isolation and historical military importance reinforced this uniqueness. These features make the region highly suitable for studying how architecture responds to climate changes across different historical periods.

In this study, we selected a number of representative architectural heritage sites within the corridor. Although the sample is limited, these sites reflect typical spatial and climatic adaptation characteristics of the region. The Hexi Corridor functions as a relatively closed geographical unit. It has a consistent climate and cultural background. Therefore, the chosen cases can effectively demonstrate broader climate-architecture relationships. This selective approach ensures that the findings are representative at a regional level. It also provides a clear and structured basis for analysis. While more sites could be studied in the future, the current selection reliably supports our conclusions. This strengthens the general applicability of the research within similar arid and semi-arid contexts.

Data sources and processing methods

The climate data in this study come from the Paleoclimate and Paleoenvironment Data Platform of China. This platform is managed by the Institute of Geology and Geophysics, Chinese Academy of Sciences. It provides extensive paleoclimate and environmental data for Asia and nearby regions. The data cover a long time span, from the Late Cretaceous (about 100 million years ago) up to the present. Our study uses data for the entire Hexi Corridor. We focused on two key climate variables: annual average temperature and annual average precipitation.

The data have a spatial resolution of 1 km. The temporal resolution is one data point every five years. This five-year interval helps show general climate trends. However, it may miss shorter-term changes. For example, it could overlook year-to-year or sudden climate events. These short-term changes might also affect how traditional buildings were designed and adapted. Despite this limitation, the data are very useful for understanding long-term climate patterns. They help us connect broad climate shifts with changes in architecture over centuries. Being clear about the data’s resolution makes our analysis more robust. It also shows where future studies could improve—by using higher-resolution data to capture more detailed climate impacts. The data were downloaded in text format from the platform. All original files were saved in XLSX format for further analysis.

An initial screening was conducted to exclude records from sites where missing values exceeded 10%. Missing values were filled using linear interpolation, and outliers were detected and corrected using the 3× standard deviation method. For time series analysis, the Mann-Kendall trend test was applied to assess long-term trends in the climate variables. To ensure data reliability, the collected data were compared with corresponding global-scale historical meteorological datasets from the National Oceanic and Atmospheric Administration (NOAA). The comparison showed high consistency (R² > 0.9) for both annual average temperature and precipitation within the Hexi Corridor. Furthermore, cross-validation was performed on the interpolated results, with the average error maintained within 5%.

Data analysis was conducted using the Python programming language, with the Pandas library utilized for data cleaning and preprocessing, and the Scikit-learn library employed for statistical modeling and computation. Quantitative architectural parameters—including material thickness (e.g., wall sections, roof layers) and roof slope angles—were obtained through a combination of field surveys and historical literature research. On-site measurements were carried out in accordance with the Chinese national standards Unified Standard for Engineering Surveying (GB 50026-2020) and Technical Specification for Ancient Building Surveying (WW/T 0080-2017), using laser distance meters and digital inclinometers to ensure metrological traceability and precision. Documented structural data were cross-referenced with officially published heritage survey reports, peer-reviewed historical construction monographs, and regional architectural archives for validation. Visualization of the analytical results was performed using the Matplotlib and Seaborn libraries. The integration of empirical field data and authoritative scholarly sources established a robust foundation for both quantitative analysis and historical trend interpretation.

Climate model

This study employs the Mann-Kendall (MK) trend test to analyze long-term trends in annual average precipitation and temperature in the Hexi Corridor spanning from the Wei-Jin to Ming-Qing periods (220–1911 AD). As a non-parametric statistical method, the MK test is particularly suitable for detecting monotonic trends in time series data that may not follow normal distributions. The analysis was conducted at a significance level of α = 0.05. The methodological procedure consists of three core steps: (1) calculation of the Kendall’s S statistic by evaluating all pairwise comparisons between data points to determine trend direction; (2) computation of the variance Var(S) with adjustment for possible duplicate values in the dataset; (3) derivation of the standardized test statistic Z to determine trend significance. The null hypothesis of no trend is rejected when the p-value is less than 0.05, with Z > 0 indicating a statistically significant upward trend and Z < 0 indicating a statistically significant downward trend. This approach provides a robust scientific framework for evaluating long-term climatic changes in the Hexi Corridor region.

Meanwhile, we implements the Mann-Kendall (MK) trend test using Python’s scipy.stats.mannkendall function to evaluate long-term trends in annual average precipitation and temperature in the Hexi Corridor. The computational core of the algorithm involves: (1) calculating the Kendall’s S statistic by comparing all pairwise data points (X_j − X_i for j > i) and summing the signs of these differences, where sign(x) = 1 for x > 0, −1 for x < 0, and 0 for x = 0; (2) computing the variance of S with tie correction using Var(S) = [n(n-1)(2n + 5) − Σt_p(t_p−1)(2t_p + 5)]/18, where t_p represents the number of ties for each group of repeated values; (3) deriving the standardized test statistic Z = (S − sign(S))/√Var(S) for S ≠ 0 (Z = 0 when S = 0); and (4) determining trend significance at α = 0.05 by comparing the two-tailed p-value against this threshold, with Z > 0 indicating upward trends and Z < 0 downward trends. The implementation integrates Pandas for data preprocessing and Scikit-learn for supplementary analytical operations. This non-parametric method provides a robust scientific basis for climate change research by effectively detecting monotonic trends in non-normally distributed climate data, as demonstrated in the long-term trend analysis of climatic elements in the Hexi Corridor (Fig. 2).

Fig. 2

Data collection and processing.

At the same time, climate data were obtained from multiple sources to ensure robustness and accuracy. These included temperature and precipitation records from the Chinese Paleoclimate and Paleoenvironment Data Platform, tree-ring proxy climate data from the China Meteorological Data Network, and historical climate reconstructions derived from classical texts such as the Zhu Kezhen curve, Records of the Grand Historian, Book of Han, Book of Tang, and Gansu local chronicles. The collected and processed climate data—incorporating both tree-ring and historical documentary evidence—were systematically compared and validated. To visualize long-term climate patterns, the Matplotlib and Seaborn libraries were used to generate plots showing changes in annual average temperature and precipitation in the Hexi Corridor from the Wei, Jin, and Southern and Northern Dynasties through the Ming and Qing Dynasties. The Mann-Kendall (MK) trend test was applied to analyze significant trends in these climate variables. Cross-verification among all data sources was conducted to guarantee data integrity and diversity, strengthening the reliability of the findings (Fig. 3).

Fig. 3

Comparison of overall climate change and different data sources during the research period.

Results

The impact of temperature changes on the evolution of traditional architectural spatial forms in the Hexi Corridor

China’s climatic variations played a decisive role in shaping architectural evolution across historical dynasties. Quantitative analysis reveals a clear correlation between temperature fluctuations and architectural adaptations: Based on trend estimates derived from the Mann-Kendall test model, for every 1 °C decrease in annual average temperature, wall thickness increased by approximately 8–12 cm, while roof slopes became shallower by 2–4 degrees to improve thermal retention. During warmer periods, agricultural prosperity facilitated more expansive and open architectural designs that emphasized natural ventilation and daylighting. In contrast, colder eras led to the emergence of enclosed, compact structures characterized by double eaves and thickened walls for improved insulation, accompanied by reduced courtyard scales to mitigate heat loss and wind exposure⁸. As an ecologically vulnerable transitional zone between agricultural and nomadic civilizations, the Hexi Corridor exhibited high sensitivity to these climatic shifts. Temperature variations directly influenced agricultural productivity, population mobility, and trade dynamics, which in turn drove distinctive architectural adaptations. The corridor’s architectural transformations in response to frequent temperature changes provide critical insights into climate-responsive design strategies within marginal ecosystems.

Correlation between traditional architectural space form and temperature in the Hexi Corridor during the Wei, Jin, Southern and Northern Dynasties

The Wei-Jin and Northern-Southern Dynasties period (220–589 AD) witnessed significant climatic fluctuations in the Hexi Corridor, with an overall cooling trend that profoundly impacted the region’s ecosystem. Decreasing temperatures led to unstable glacial meltwater supplies and increased extreme weather events, severely affecting agriculture and Silk Road transportation⁹. These climatic changes provide crucial context for understanding historical human activities in the region. The architectural legacy of this era is exemplified by the Luotuo City ruins in Zhangye, capital of the Xiongnu-led Beiliang Kingdom (397–439 AD)¹⁰. As a cultural hybrid of nomadic and Han traditions, its spatial organization likely reflected both influences. While no wooden structures survive, the well-preserved city walls allow reconstruction of its spatial form and analysis of its climate-responsive features (Fig. 4), offering insights into temperature-architecture correlations during this transitional period.

Fig. 4: Camel City spatial form and temperature trends.

Wei-Jin period analysis (a) Spatial Form Map of Camel City Site / (b) Data validation analysis based on field research.

Figure 4 indicates that the Hexi Corridor experienced relatively cold conditions during the Wei-Jin and Northern-Southern Dynasties (220–589 AD), with estimated annual temperatures of 5–8 °C. The region’s significant diurnal temperature variations and harsh winters prompted distinctive architectural adaptations, as evidenced by Luotuo City’s thick rammed-earth walls and compact layout designed to minimize heat loss and wind exposure¹⁰. The cold climate likely exacerbated agricultural challenges, intensifying conflicts between nomadic tribes and centralized regimes. As a strategic frontier, the Hexi Corridor’s architectural spaces became increasingly enclosed and defensive, reflecting both climatic pressures and geopolitical tensions. This period’s characteristic heavy, inward-oriented building forms thus emerged from the intersection of environmental and socio-political factors.

Correlation between traditional architectural space form and temperature in the Hexi Corridor during the Sui and Tang Dynasties

The Sui-Tang period (581–907 AD) in the Hexi Corridor experienced warmer climatic conditions, known as the “Sui-Tang Warm Period,” which facilitated agricultural development and human settlement¹¹. Climate proxies like ice cores and tree rings indicate stable, warm temperatures during this era, though regional variations existed—with relatively humid conditions in eastern areas (e.g., Wuwei) compared to the drier western regions (e.g., Dunhuang)¹². The most significant architectural relic from this period is the Kumbum Monastery at Suoyang City in Guazhou County, originally built during the Tang Dynasty as the Kaiyuan Temple¹³. This 15,000 m² complex features distinct outer courtyard and inner temple sections, with surviving elements including mountain gates, halls, and pagodas. As an important Buddhist center along Xuanzang’s westward journey, its spatial organization reflects both religious functions and climate-responsive design principles of the warm period (Fig. 5). Although the original wooden structures are lost, the remaining relics enable reconstruction of its spatial configuration and analysis of its temperature-adaptive features.

Fig. 5: Kumbum Monastery spatial form and temperature trends.

Sui-Tang period analysis (a) Spatial map of Kumbum Monastery in Suoyang City / (b) Data validation analysis based on field research.

Figure 5 suggests the Hexi Corridor’s annual temperature during the Sui-Tang period (581–907 AD) ranged between 8–10 °C, as reconstructed from tree rings, lake sediments, and ice core data¹⁴. This warmer climate significantly influenced architectural spatial organization, as evidenced by the Kumbum Monastery at Suoyang City. The complex exhibits open spatial arrangements with ample courtyards between structures, facilitating ventilation and lighting to enhance comfort in warm conditions. The monastery’s main halls feature expansive interiors to accommodate large congregations, reflecting reduced needs for thermal insulation. Its predominant south/southeast orientation combines traditional feng shui principles with climate adaptation—maximizing winter sunlight while enabling summer ventilation¹⁵. Excavated corridor remnants further demonstrate sophisticated passive cooling strategies. These architectural responses to the warm period reflect broader socioeconomic impacts: agricultural prosperity and political stability increased population density and religious activities, necessitating more spacious, ventilated structures. The resulting open, dispersed layouts with emphasized north-south orientations directly correlate with Sui-Tang temperature patterns.

Correlation between traditional architectural space forms and temperature in the Hexi Corridor during the Song, Liao, and Jin Dynasties

The Hexi Corridor experienced significant climatic fluctuations during the Song-Liao-Jin period (10–13th centuries), transitioning from warm conditions in the 11–12th centuries to cooler temperatures by the late Southern Song. This period, corresponding to the Medieval Climate Anomaly, saw temperatures potentially surpassing those of the Sui-Tang era before entering a cooling phase¹⁶. The architectural response to these variations is exemplified by Zhangye Dafo Temple (constructed 1098 AD). This 220-meter east-west complex, while reconstructed in later dynasties, preserves its original Song-era courtyard layout. Its spatial organization—featuring the Great Buddha Hall, Diamond Throne Pagoda, and distinct courtyards like the Shanxi Guild Hall—demonstrates adaptive strategies to climatic transitions (Fig. 6). The temple’s balanced combination of expansive ceremonial spaces and enclosed areas reflects both the warmer initial phase and subsequent cooling trend of this period.

Fig. 6: Zhangye Dafosi spatial form and temperature trends.

Song-Liao-Jin period analysis (a) The spatial map of Zhangye Dafo Temple / (b) Data validation analysis based on field research.

Figure 6 reveals that the Hexi Corridor experienced significant temperature fluctuations (6–11 °C) during the Song-Liao-Jin period (10–13th centuries), transitioning from the warm Medieval Climate Anomaly to the cooler Little Ice Age¹⁷. This climatic shift, particularly the late Northern Song cooling, severely impacted agricultural productivity and trade while triggering nomadic migrations and conflicts. The architectural response is exemplified in Zhangye Dafo Temple (mid-11th century Western Xia period), where thick walls and small windows provided essential winter insulation while carefully designed courtyard corridors facilitated summer ventilation. The temple’s enclosed inner courtyards created protective microclimates that buffered seasonal extremes, with compact spatial arrangements mitigating winter cold and strategic openings allowing heat dissipation. This transitional-period architecture skillfully balanced contradictory thermal requirements through concentrated building clusters for wind protection, proportioned courtyards for seasonal airflow regulation, and dual-orientation structures addressing temperature variations. The temple’s spatial organization thus embodies sophisticated adaptations to the region’s climatic volatility during this pivotal historical transition, demonstrating how traditional architecture dynamically responded to changing environmental conditions.

The correlation between traditional architectural spatial forms and temperature in the Hexi Corridor during the Yuan, Ming, and Qing dynasties

The Hexi Corridor experienced significant climatic variations during the Yuan-Ming-Qing period (13–19th centuries), transitioning through phases of the Little Ice Age. While the Yuan Dynasty marked the onset of cooler conditions, temperatures fluctuated considerably—warming briefly in early Ming before declining sharply by late Ming, then stabilizing in early Qing only to cool again in the 18–19th centuries. These changes profoundly influenced regional architecture, as exemplified by Wuwei Confucian Temple (completed 1439 AD). This expansive complex, organized along a traditional north-south axis across its 30,096 m² site, features three distinct sections: Wenchang Palace, the main Confucian Temple, and Liangzhou Confucian Academy. As the largest preserved Confucian temple in northwest China, its spatial organization reflects adaptive responses to climatic challenges—with compact building clusters providing wind protection during cold periods while maintaining ceremonial grandeur. The temple’s balanced proportions and orientation demonstrate sophisticated adjustments to the region’s variable temperatures during this extended climatic transition (Fig. 7), offering valuable insights into architectural adaptations under fluctuating environmental conditions.

Fig. 7: Wuwei Confucian Temple spatial form and temperature trends.

Yuan-Ming-Qing period analysis (a) The spatial map of Wuwei Confucian Temple / (b) Data validation analysis based on field research.

Figure 7 indicates the Hexi Corridor’s annual temperature during the Yuan-Ming-Qing period (13–19th centuries) fluctuated between 5–7 °C, with frequent variations within this range. These colder conditions shortened growing seasons, causing agricultural instability that threatened food security and political order¹⁸. Architecturally, the climate shift prompted significant adaptations, as demonstrated by Wuwei Confucian Temple (1439 AD). Compared to Song-era structures, the complex shows reduced corridor spaces, denser building clusters, and smaller courtyards—all enhancing wind and cold resistance. The addition of perimeter walls further protected against harsh weather. The colder climate also critically impacted construction materials. Reduced timber yields due to shorter growth periods and winter frost damage¹⁹ led to greater reliance on brick and stone. However, these materials’ poorer insulation necessitated thicker walls, which in turn limited structural spans. Consequently, the temple features smaller, scattered buildings enclosing multiple compact courtyards—a spatial solution compensating for material limitations while maintaining functional areas. This architectural configuration, characterized by enclosed layouts, modest individual volumes, and densely arranged courtyards, directly responded to the region’s prolonged cold period²⁰. The complex thus embodies how climatic pressures influenced both construction techniques and spatial organization during China’s Little Ice Age.

The impact of precipitation changes on the evolution of traditional architectural spatial forms in the Hexi Corridor

Ancient Chinese architectural forms evolved in direct response to precipitation patterns, demonstrating sophisticated environmental adaptation strategies. Quantitative analysis based on the Mann-Kendall test model reveals a measurable relationship between rainfall and architectural features: for every 20 mm decrease in annual precipitation, roof slopes flattened by approximately 3–5 degrees to reduce surface area and minimize rainwater collection requirements. During high-rainfall periods, structures featured steep roofs (often exceeding 40 degrees) and elevated foundations for effective drainage, particularly in southern regions. Conversely, arid conditions prompted water conservation designs featuring flattened roofs (as low as 10–15 degrees), thicker walls, and integrated courtyard water storage systems. The Hexi Corridor’s unique position along the 200 mm precipitation isopleth made it exceptionally sensitive to hydrological variations. When precipitation exceeded this threshold, agricultural civilizations flourished and Central Plain regimes expanded control; below it, nomadic cultures dominated. These hydrological fluctuations not only shaped the region’s fragile ecosystem but also influenced socio-political dynamics, ultimately manifesting in architectural spatial configurations. The corridor’s traditional buildings thus embody a quantifiable record of climate-human interactions throughout history, with roof morphology serving as a particularly sensitive indicator of hydrological changes.

The correlation between traditional architectural spatial forms and rainfall in the Hexi Corridor during the Wei, Jin, Southern and Northern Dynasties period

The Wei-Jin and Northern-Southern Dynasties period (220–589 AD) witnessed significant precipitation fluctuations in the Hexi Corridor, with an overall drying trend. While rainfall remained relatively stable during the Wei-Jin era (220–420 AD), the subsequent Northern-Southern Dynasties (420–589 AD) saw decreasing precipitation that destabilized oasis agriculture and accelerated desertification²¹. This climatic shift is reflected in the region’s architecture, particularly the Mati Temple Grottoes (constructed during Northern Liang rule). This 1600-year-old Buddhist complex in Sunan County comprises seven sections with over 70 niches, including Shengguo Temple and Qianfo Cave. Although most original wooden structures were lost to warfare, the preserved spatial organization demonstrates adaptive responses to aridification. The grottoes’ strategic mountain-embedded location and compact layout minimized water dependence while providing natural insulation—features that became increasingly vital as precipitation patterns grew more erratic. These architectural solutions illustrate how builders adjusted to the corridor’s changing hydrological conditions during this transitional historical period.

Figure 8 reveals that the Hexi Corridor received only 100–200 mm annual precipitation during the Wei-Jin and Northern-Southern Dynasties (220–589 AD), classifying it as a semi-arid zone. Precipitation patterns showed strong seasonality—limited summer thunderstorms from weakened monsoons, and virtually no winter/spring rainfall²². This aridity triggered ecological and political consequences: agricultural decline weakened state power while desiccated pastures drove nomadic raids, exacerbating regional conflicts. The Mati Temple Grottoes exemplify architectural adaptations to these dry conditions. Their mid-slope excavation location and daring overhanging structures (possible only in low-rainfall environments) demonstrate climate-responsive design. The temple’s distinctive features—gently sloped roofs with upturned eaves (Fig. 8)—directly resulted from minimal precipitation concerns, eliminating need for steep drainage angles. These elements collectively created the characteristic “flying” visual effect typical of Hexi Corridor architecture during this arid period. The grottoes’ spatial organization thus physically manifests both the environmental constraints and construction innovations of this climatically challenging era.

Fig. 8: Mati Temple spatial form and precipitation trends.

Wei-Jin period analysis (a) The spatial map of Mati Temple / (b) Data validation analysis based on field research.

Correlation between traditional architectural spatial form and rainfall in the Hexi Corridor during the Sui and Tang Dynasties

The Sui-Tang period (581–907 AD) in the Hexi Corridor maintained semi-arid conditions overall, though precipitation occasionally exceeded 200 mm, particularly during a relatively humid phase in early Tang that boosted agriculture and oasis development²³. This climatic variability is reflected in regional architecture like the Zhangye Wooden Pagoda, originally constructed in 582 AD during the Sui Dynasty. Though repeatedly rebuilt (the current structure being a nine-story brick-wood hybrid), it preserves essential Sui-Tang spatial characteristics. The pagoda’s design—including its elevated base and roof proportions—demonstrates adaptations to the corridor’s transitional precipitation patterns, balancing between semi-arid norms and occasional wetter periods (Fig. 9). These features illustrate how Sui-Tang builders responded to the region’s delicate hydrological balance while maintaining architectural grandeur.

Fig. 9: Zhangye Wooden Pagoda spatial form and precipitation trends.

Sui-Tang period analysis (a) The spatial map of Zhangye Wooden Pagoda / (b) Data validation analysis based on field research.

Figure 9 indicates that the Sui-Tang period (581–907 AD) in the Hexi Corridor experienced relatively stable precipitation, slightly higher than during the Wei-Jin era, which supported irrigated agriculture and population growth²⁴. This hydrological stability, combined with the region’s role in East-West cultural exchange, influenced distinctive architectural adaptations exemplified by the Zhangye Wooden Pagoda (constructed 582 AD).

The pagoda’s design reflects careful hydrological considerations: its deeply protruding eaves with moderate slopes addressed drainage needs, while specialized rainwater collection systems (including tile flanges and wooden grooves) managed precipitation runoff. The elevated base prevented water damage, demonstrating sophisticated moisture control. Improved climatic conditions during this period also enabled greater use of wood construction, as seen in the pagoda’s complex wooden bracketing system supporting its characteristic overhanging roofs. These elements collectively created the structure’s elegant, dynamic profile—a hallmark of Sui-Tang architecture in the Hexi Corridor that balanced functional water management with aesthetic grandeur. The pagoda thus embodies how stable precipitation patterns facilitated both technical innovation and artistic expression in this pivotal historical period.

Correlation between traditional architectural space forms and rainfall in the Hexi Corridor during the Song, Liao, and Jin Dynasties

During the Song-Liao-Jin period (10–13th centuries), the Hexi Corridor experienced drier conditions as global cooling marked the early Little Ice Age. Weakened East Asian monsoons reduced Pacific moisture transport, decreasing precipitation compared to Sui-Tang levels²⁵. This aridification significantly impacted regional development. The Western Xia’s Xiliang Prefecture Hall in Wuwei exemplifies contemporary architectural responses. Its well-preserved “five-bay seven-beam” structure demonstrates adaptations to drier conditions—featuring compact layouts and reduced roof pitches that minimized water collection needs while maintaining imperial grandeur (Fig. 10). This architectural relic provides valuable insights into how builders adjusted to the corridor’s changing hydrological patterns during this climatic transition period.

Fig. 10: Xiliang Prefecture lobby spatial form and precipitation trends.

Song-Liao-Jin period analysis (a) Space map of the lobby of Xiliang Prefecture in Western Xia / (b) Data validation analysis based on field research.

Figure 10 reveals that precipitation in the Hexi Corridor dropped significantly to 180–220 mm during the Song-Liao-Jin period (10–13th centuries), triggering a cascade of ecological and socioeconomic consequences²⁶. The resulting environmental degradation weakened central governance while empowering local factions, ultimately destabilizing this crucial Silk Road artery and diverting trade to alternative routes. These climatic and political shifts profoundly influenced regional architecture, as exemplified by the Western Xia’s Xiliang Prefecture Hall. Faced with dwindling timber resources, builders adopted innovative column-reduction techniques and earth-wood composite construction, resulting in more compact, enclosed spaces that contrasted sharply with the expansive designs of the Tang era. The structure’s simplified bracket sets and gently sloping roofs with shortened eaves reflected both reduced hydrological pressures and the Dangxiang people’s emerging aesthetic preferences. This architectural transformation demonstrates how decreasing precipitation reshaped not only construction materials and techniques but also cultural expressions, as the region transitioned from Han to Western Xia dominance. The hall’s spatial configuration thus encapsulates the complex interplay between environmental constraints, political realignments, and architectural evolution during this pivotal period of climatic and cultural change in the Hexi Corridor.

The correlation between traditional architectural spatial forms and rainfall in the Hexi Corridor during the Yuan, Ming, and Qing dynasties

The precipitation patterns in the Hexi Corridor fluctuated significantly during the Yuan-Ming-Qing period (13–19th centuries), with the relatively warm Yuan Dynasty experiencing adequate rainfall that supported agriculture, while the Ming Dynasty’s Little Ice Age brought drier conditions that worsened through the Qing Dynasty before modest recovery in the late 19th century²⁷. These climatic variations are reflected in regional architecture like the Yongchang Bell and Drum Tower (constructed 1586, rebuilt 1767), a rare surviving Ming-era wooden structure featuring a distinctive double-eave hipped roof and 24.5-meter tall design. The tower’s spatial organization—including its substantial base and carefully proportioned eaves—demonstrates adaptive responses to the corridor’s changing precipitation patterns, with its architectural evolution mirroring the transition from Yuan-period relative abundance to Qing-era aridity (Fig. 11), while maintaining essential ceremonial functions throughout these climatic fluctuations.

Fig. 11: Yongchang Bell-Drum Tower spatial form and precipitation trends.

Yuan-Ming-Qing period analysis (a) The spatial map of Yongchang Bell and Drum Tower / (b) Data validation analysis based on field research.

Figure 11 illustrates the precipitation decline to 170–200 mm during the late Yuan through Qing periods, which severely impacted the Hexi Corridor’s ecosystem and socioeconomic stability²⁸. The resulting water scarcity diminished agricultural output, weakened central governance, and ultimately contributed to the Silk Road’s decline as trade routes became increasingly untenable. These arid conditions also fundamentally transformed regional architecture, as evidenced by the Yongchang Bell and Drum Tower (1586). The structure’s heavy brick construction and enclosed spatial form reflect adaptation to timber scarcity, while its distinctive curved hipped roof—featuring a central flat section with minimal peripheral eaves and representing a form of luding (a traditional Chinese roof style characterized by a flattened central area surrounded by sloping eaves, often used in arid regions for rainwater harvesting and thermal regulation)—embodies a pragmatic compromise between Han architectural traditions and arid climate necessities²⁹. This hybrid design eliminated drainage requirements while maintaining cultural symbolism, demonstrating how Ming Dynasty builders innovatively responded to environmental constraints. The tower’s overall massing and material choices thus embody the direct influence of the Hexi Corridor’s prolonged drought conditions on architectural evolution, showcasing the intricate relationship between climate change, material availability, and cultural preservation in traditional Chinese architecture.

Discussion

The evolution of architectural spatial forms in the Hexi Corridor from the Northern and Southern Dynasties to the Qing Dynasty profoundly reflects the dynamic interplay between climate change and human lived experience. From a phenomenological perspective, these transformations represent not merely technical adaptations but embodied responses to natural forces by ancient craftsmen, constituting what may be termed “Climatic Embodiment”—a process through which architectural responses to meteorological influences are translated into perceptible living systems via material choices, spatial configurations, and construction details, thereby establishing an interactive relationship among architecture, climate, and the human body. The thickened rammed earth walls of the Wei-Jin period correlate with historical records such as “windblown sands eroded the crumbling city walls” from the Book of Jin, revealing a visceral awareness of aeolian hazards. The shift from open to enclosed layouts in Tang Dynasty Buddhist temples manifests spatial adaptations to increasing aridity and cold. The adjusted roof angles during the Ming-Qing periods, documented alongside “snow-collapsed beams” in local gazetteers, further demonstrate direct climatic influences on architectural forms. These spatial practices essentially materialize climatic embodiment, where architectural elements collectively form an inhabited sign system that encapsulates regional wisdom of dwelling, ultimately realizing a trinity of “architecture-climate-body” interaction.

Based on the phenomenological analysis above, we will establish an analytical framework of “climate change—architectural spatial response” to discuss how climate change affects the evolution of traditional architectural spatial forms in the Hexi Corridor from multiple dimensions.

The analysis demonstrates that temperature significantly influenced the spatial organization of building clusters in the Hexi Corridor, primarily through thermal comfort requirements³⁰. During colder periods (Wei-Jin and Yuan-Ming-Qing eras), architectural groups adopted compact, enclosed configurations with minimal spacing between structures and prominent perimeter enclosures to retain heat. Conversely, the warmer Sui-Tang period saw more dispersed, open arrangements with greater building separation and reduced enclosure, facilitating natural ventilation. These distinct spatial patterns—clustered/enclosed versus discrete/open—represent direct architectural responses to thermal conditions, illustrating how temperature variations fundamentally shaped the region’s traditional building group formations. The consistent correlation between climatic phases and spatial configurations underscores temperature’s primary role in determining architectural cluster morphology in this environmentally sensitive region.

The case analysis reveals that temperature variations in the Hexi Corridor fundamentally influenced architectural materials and spatial characteristics. During warmer periods (Sui-Tang and early Northern Song), abundant timber resources enabled extensive wood construction, permitting dynamic, transparent spaces with projecting elements and elevated components that capitalized on wood’s mechanical properties³¹. The mild climate reduced insulation needs, resulting in more open, fluid spatial configurations. Conversely, colder eras (Wei-Jin and Ming-Qing) saw harsher environments with limited timber, necessitating earth and masonry construction. These materials’ inferior insulation required thicker walls for thermal protection, while their structural limitations prevented expansive cantilevers or spans, producing more rigid, enclosed spatial forms. This material-structural evolution directly reflects temperature’s dual impact: governing both resource availability (timber quantity) and architectural requirements (thermal performance), which collectively shaped the region’s shifting architectural expression from light/transparent to heavy/enclosed configurations in response to climatic fluctuations.

Historical analysis reveals temperature fluctuations profoundly influenced the Hexi Corridor’s political-economic stability and, consequently, its architectural evolution. As noted by Professor Zhu Kezhen, Chinese dynastic changes correlate closely with climatic variations, particularly in this ecologically sensitive transition zone. During warmer Sui-Tang periods, agricultural prosperity supported larger architectural scales and more elaborate designs, as economic abundance allowed craftsmen to prioritize aesthetic expression over cost efficiency. Conversely, the colder Ming-Qing era brought reduced crop yields, economic decline, and population decrease, leading to more constrained, cost-conscious building forms with narrower spatial configurations. Temperature-induced political instability during colder periods further reinforced enclosed architectural designs as defensive measures against rebellions. This demonstrates how climate changes indirectly shaped architectural spatial forms through a cascading effect on agricultural productivity, economic conditions, and social stability—with prosperous warm periods enabling expansive, artistic structures while challenging cold phases necessitated compact, utilitarian designs with heightened security features³².

From a socio-cultural perspective, temperature changes have profoundly influenced the ethnic composition and architectural styles of the Hexi Corridor region. Historically, as a vital passage connecting the Central Plains and the Western Regions, the Hexi Corridor’s climate fluctuations directly shaped the migration and settlement patterns of its inhabitants. During warmer periods, such as the Han and Tang dynasties, rising temperatures and increased precipitation transformed the Hexi Corridor into a lush, water-rich area, attracting northern nomadic tribes to migrate southward. These groups intersected with the agricultural communities of the Central Plains, fostering a multi-ethnic society. This integration introduced diverse cultural elements, which were reflected in the region’s architecture. The Central Plains’ timber-framed structures, the Western Regions’ arched domes, and the nomadic tent styles blended harmoniously, giving rise to a unique architectural aesthetic. For instance, the murals and painted decorations of Dunhuang’s Mogao Grottoes exemplify the fusion of Central Plains, Western Regions, and Buddhist artistic traditions. Conversely, during colder periods, such as the Little Ice Age of the Ming and Qing dynasties, declining temperatures and deteriorating ecosystems forced some nomadic groups to relocate, while agricultural communities from the Central Plains migrated due to policy shifts or conflicts. This further deepened ethnic and cultural integration. Against this multicultural backdrop, Hexi Corridor architecture evolved to emphasize practicality and adaptability. Features such as thick walls, small windows, and flat roofs were designed to withstand harsh winds, sandstorms, and temperature extremes, while inner courtyards were optimized for light and ventilation. Additionally, the spread of religious traditions, including Buddhism and Islam, left a lasting imprint on architectural styles, with the construction of temples and mosques enriching the region’s decorative and spatial forms. In summary, temperature changes indirectly shaped the Hexi Corridor’s architectural diversity and functional design by influencing ethnic dynamics and cultural exchange, highlighting the intricate interplay between natural forces and human creativity³³.

The analysis demonstrates that precipitation primarily influenced the Hexi Corridor’s architectural spatial form through roof and foundation adaptations. During high-rainfall periods like the Sui-Tang dynasties, buildings featured steeply pitched roofs for effective water drainage and elevated platforms to prevent flooding, ensuring structural integrity and interior protection. Conversely, in drier eras such as the Yuan-Ming-Qing periods, reduced precipitation enabled shallower roof slopes and lower foundations, with the emergence of cost-efficient curved hipped roofs that maintained cultural aesthetics while minimizing construction expenses. These hydrological adaptations reveal a clear pattern: roof pitch and foundation height directly correlated with precipitation levels, creating distinct architectural profiles—from the tall, steep-roofed structures of wet periods to the more modest, gently sloping forms during arid times. This precipitation-driven evolution of architectural elements fundamentally shaped the region’s building morphology while balancing functional requirements with economic considerations across different climatic phases³⁴.

Botanical studies confirm that precipitation critically determines tree growth by regulating soil moisture and nutrient absorption. During the Sui-Tang period’s high rainfall, abundant timber enabled dynamic wooden structures with transparent spaces in the Hexi Corridor. Conversely, the arid Yuan-Ming-Qing eras saw limited tree growth, forcing reliance on brick/stone construction that created enclosed, heavy spatial forms. Thus, precipitation indirectly shaped architectural spatial characteristics through its fundamental control of material availability, mirroring temperature’s influence on building morphology in this climatically sensitive region.

The Hexi Corridor’s historical position along the critical 200 mm precipitation isopleth profoundly influenced its political and architectural evolution. When precipitation exceeded this threshold, agricultural prosperity enabled Han Chinese control, with their architectural traditions—characterized by the use of dougong (an intricate structural element of traditional Chinese architecture consisting of interlocking wooden brackets mounted on columns to support the roof and transfer its load), elegantly curved roofs, and expansive platforms—dominating the region’s built environment. However, when rainfall dropped below 200 mm, rendering cultivation nearly impossible, nomadic tribes assumed control, introducing their distinct architectural aesthetic of simplified, enclosed forms without complex wooden elements or dramatic roof contours. This hydrological-political relationship created alternating architectural expressions: during high-precipitation periods like Sui-Tang, structures displayed the Han cultural preference for sophisticated wooden frameworks and graceful curves, while in arid eras such as Wei-Jin and Song-Liao-Jin, buildings reflected nomadic tastes for utilitarian, unadorned designs. Furthermore, intensified conflicts between nomadic and agricultural civilizations during dry periods reinforced defensive architectural features, compounding the enclosure and simplicity of spatial forms. Thus, precipitation fluctuations indirectly shaped the Hexi Corridor’s architectural character through a cascading effect on agricultural viability, political control, and cultural expression, with the 200 mm threshold serving as a pivotal determinant in the region’s architectural transitions between Han Chinese and nomadic design paradigms³⁵.

From a socio-cultural perspective, changes in precipitation have profoundly influenced agricultural patterns and architectural styles in the Hexi Corridor region. Situated in the arid northwest of China, the Hexi Corridor’s agricultural prosperity and production methods have historically been directly tied to fluctuations in rainfall. During periods of relatively abundant precipitation, such as the Han and Tang dynasties, agriculture thrived, with irrigation-based farming forming a stable oasis economy. This agricultural success encouraged population growth and settlement, leading to the development of villages and towns. Economic prosperity, in turn, fostered a trend toward elaborate and ornate architectural decoration, as seen in the widespread use of brick carving, wood carving, and painted designs, reflecting the aesthetic aspirations of an agrarian society. Conversely, during drier periods, reduced rainfall posed significant challenges to agriculture, prompting a shift toward semi-agricultural, semi-pastoral, or even nomadic economies. This transition necessitated more practical and adaptable building designs. To combat drought and sandstorms, structures were often built with thick walls, small windows, and flat roofs to minimize water evaporation and withstand harsh weather. Courtyards were designed to be more compact, optimizing land and water use. Additionally, changes in precipitation influenced the choice of building materials, with a greater reliance on locally available resources such as raw earth and rammed soil during droughts, resulting in a simpler, more utilitarian architectural style. In summary, precipitation changes have indirectly shaped the Hexi Corridor’s architectural aesthetics and spatial layouts by altering agricultural practices and economic structures. This interplay highlights both the constraints imposed by the natural environment and the ways in which social and cultural factors have adapted to and influenced architectural development.

This study reveals how temperature and precipitation changes fundamentally shaped the spatial evolution of traditional architecture in the Hexi Corridor from the Wei-Jin period to the Qing Dynasty. The architectural trajectory transitioned from compact, enclosed forms during cold/dry periods (Wei-Jin and Yuan-Ming-Qing) to expansive, open configurations in warm/wet eras (Sui-Tang), with intermediate stages during Song-Liao-Jin. Key transformations included: clustered building groups giving way to dispersed layouts, steep roofs flattening, and elevated bases lowering in response to climatic shifts. These adaptations demonstrate a sophisticated balance between environmental responsiveness and cultural continuity, providing new insights into climate-adaptive architecture. The research establishes a methodological framework for analyzing architectural evolution through climatic lenses while accounting for historical context, offering valuable perspectives for both heritage conservation and contemporary climate-responsive design in similar arid regions.

Research has found that the Traditional architecture in the Hexi Corridor exhibits a regular adaptation to the fluctuations of dry, cold, warm, and humid climate: during the dry and cold period, it is characterized by a compact and enclosed centralized layout, gentle slope roof, and high walls to resist cold winds and provide insulation; During the warm and humid period, the layout tends to be open and stretched, with steep roofs that facilitate ventilation, heat dissipation, and drainage. This historical experience shows that there is a profound dynamic response mechanism between architectural form and climate conditions, suggesting that contemporary design should pay attention to regional climate characteristics and fully absorb adaptive strategies from traditional wisdom. Specifically, this study suggests that in newly constructed buildings in arid and cold regions, the traditional experience combination of “compact courtyard+gentle slope roof+thick wall insulation” should be adopted systematically. Compact layout can reduce external exposed surfaces and lower heat loss; The gentle slope roof combines drainage efficiency with the potential for winter snow insulation; Thick walls utilize thermal inertia to regulate indoor temperature fluctuations, enhancing the building’s adaptability under extreme temperature conditions. These strategies not only help significantly improve the energy efficiency and climate resilience of buildings in arid areas, but also continue the cultural genes of local architecture, achieving effective connection from historical samples to modern translation, thus jointly promoting the coordinated development of climate adaptability and heritage inheritance of buildings at the functional and cultural levels³⁶.

From the perspective of heritage preservation and adaptive reuse, the evolution of traditional architectural spatial forms in the Hexi Corridor highlights its profound cultural significance in adapting to climatic conditions. As a quintessential example of arid and semi-arid regions, the traditional buildings of the Hexi Corridor have effectively addressed climatic challenges such as sandstorms, droughts, and extreme temperature fluctuations through features like thick walls, small windows, and inner courtyards, embodying a unique ecological wisdom³⁷. These structures are not only vital components of cultural heritage but also testaments to the harmonious coexistence between ancient communities and their natural environment. Preserving these traditional spatial forms in heritage conservation efforts not only safeguards historical and cultural legacies but also perpetuates this ecological wisdom. Furthermore, in the process of adaptive reuse, traditional architectural spaces are repurposed with new functions, such as converting old residences into cultural exhibition spaces or guesthouses. This approach retains their original climate-adaptive features while infusing them with modern vitality. The integration of preservation and adaptive reuse not only revitalizes traditional architecture but also offers valuable insights for contemporary architectural design, underscoring the practical relevance of cultural heritage in addressing climate change. The evolution of traditional architecture in the Hexi Corridor thus represents both a technological achievement in climate adaptation and a cultural legacy, showcasing humanity’s enduring ingenuity in adapting to and innovating within natural environments.

This study investigates the historical evolution of traditional architectural spatial forms in China’s Hexi Corridor from the Wei, Jin, Southern and Northern Dynasties to the Qing Dynasty through the lens of climate change. However, several limitations should be acknowledged. Firstly, the scarcity of historical documents and archaeological materials may result in insufficient representativeness of architectural samples from certain periods, thereby limiting the generalizability of the findings. Secondly, while the Hexi Corridor serves as a representative region, the conclusions drawn may not be fully applicable to other areas with distinct climatic conditions or cultural contexts. Furthermore, the research primarily relies on historical literature and field studies, with limited application of modern technologies such as 3D scanning and remote sensing, which could affect the accuracy and comprehensiveness of the data³⁸.

Future research should explore several promising directions. First, integrating modern conservation technologies is crucial. Digital modeling and virtual reality can improve documentation. They allow precise analysis of traditional buildings’ spatial features. Second, policy analysis needs more attention. Studying how heritage policies shape traditional architecture can support current conservation efforts. Third, expanding the geographic scope is important. Comparative studies between the Hexi Corridor and other regions—whether different in climate or culture—can reveal shared principles and regional differences in architectural evolution. Additionally, new technical methods should be incorporated. For example, combining drone remote sensing with building energy simulation tools (such as EnergyPlus) could help quantify the climate regulation efficiency of traditional buildings. This approach would make performance evaluation more accurate. Furthermore, comparative studies on the interaction mechanisms between climate and buildings in cold-humid regions are also recommended. Such studies would enhance the applicability and extensiveness of the research. These developments would make future studies more comprehensive and practical. They can also provide a stronger theoretical basis for the protection and sustainable development of traditional architecture³⁹.

This study focuses on temperature and precipitation as primary climatic factors influencing traditional architecture in the Hexi Corridor, as these elements significantly impacted living conditions and building forms⁴⁰. While climate encompasses other elements like humidity and wind patterns, their effects were comparatively minimal in this arid region⁴¹. The substantial variations in thermal and hydrological conditions directly shaped architectural adaptations, making them ideal indicators for analyzing climate-architecture relationships in this unique geographical context.

Previous studies on climate-responsive architecture have predominantly examined static temperature conditions within specific regions and periods, largely overlooking the dynamic impacts of temporal temperature variations. This research gap is particularly significant given the Hexi Corridor’s historical temperature fluctuations, which necessitated continuous architectural adaptations to maintain thermal comfort across different climatic phases. Recent scholarship has begun systematically investigating these relationships by correlating historical temperature data with architectural evolution, analyzing how thermal variations influence building design, layout, and material selection. However, this research presents considerable methodological challenges, as architectural forms simultaneously respond to cultural, socioeconomic, and political factors—all of which may themselves be temperature-influenced. This study specifically addresses these complexities by developing analytical frameworks to isolate temperature’s architectural impacts from other confounding variables in the Hexi Corridor context. Focusing on distinct spatial elements most directly shaped by thermal conditions while excluding non-climatic influences, the research aims to elucidate the fundamental mechanisms through which temperature changes drove architectural adaptations in this region. By establishing these causal relationships, the study provides innovative methodological approaches for understanding climate-architecture interactions, offering new perspectives for analyzing traditional buildings’ thermal adaptation strategies while acknowledging the inherent complexities of disentangling environmental and cultural factors in architectural evolution.

Previous research on precipitation’s architectural impacts has primarily examined static drainage solutions for specific regions and periods, overlooking the dynamic effects of long-term rainfall variations. In the Hexi Corridor, where precipitation has fluctuated significantly throughout history, architectural forms evolved distinct adaptive strategies—from steep roofs and elevated foundations during wet periods to flattened roofs and reduced timber use in arid eras. These hydrological adaptations profoundly shaped the region’s architectural development, though their study presents methodological challenges similar to temperature research. Quantitative historical precipitation data remains scarce, while rainfall’s effects intertwine with political, economic, and cultural factors that may themselves be precipitation-influenced⁴². This study seeks to disentangle these complex relationships by analyzing how precipitation changes first altered the Hexi Corridor’s natural and cultural environments, which subsequently drove specific architectural adaptations. By focusing on precipitation’s most direct architectural impacts while accounting for secondary socioeconomic influences, the research aims to clarify the mechanisms through which hydrological variations shaped building forms in this climatically sensitive region, providing a more nuanced understanding of architecture’s response to environmental change⁴³.

From the perspective of climate change, the architectural evolution of the Hexi Corridor region reflects a dynamic adaptation to shifting environmental conditions across different historical periods. During the Wei, Jin, Southern, and Northern Dynasties, the region experienced a relatively dry climate, prompting the spatial form of group buildings to prioritize military defense. Structures were predominantly constructed using civil engineering materials, which were well-suited to the cold and arid local climate. These buildings emphasized enclosure and windproofing to combat sandstorms, reflecting the need for protection against harsh environmental conditions. In the Sui and Tang dynasties, as the climate became warmer and wetter, the spatial configuration of group buildings evolved towards more open and multifunctional designs. Courtyard scales expanded, and buildings incorporated more ventilation corridors, which provided wind protection during winter and facilitated heat dissipation in summer. This shift in architectural design catered to the diverse climatic needs of the period, showcasing a balance between functionality and environmental adaptation. During the Song, Liao, and Jin dynasties, the climate gradually turned colder and drier, leading to a greater emphasis on thermal insulation in group building spaces, particularly in border areas. The defensive and insulating features of these structures became more pronounced, with courtyards becoming more enclosed and their scales shrinking. This architectural response highlights the increasing importance of climate resilience during this era. By the Yuan, Ming, and Qing dynasties, the climate had grown even colder, further influencing the spatial forms of buildings. Structures were designed with a heightened focus on wind and sand prevention, as well as insulation. The scale of group buildings continued to decrease, reflecting both the need to adapt to harsher climatic conditions and the diverse cultural demands of the time. Overall, the spatial evolution of group buildings in the Hexi Corridor demonstrates a cyclical trend: transitioning from small-scale to large-scale and then back to small-scale in response to climate changes; shifting from enclosed to open and then returning to enclosed designs; and evolving from fences to outer corridors and then back to fences⁴⁴.

Analyzing the spatial changes in individual buildings reveals a similar pattern of adaptation. During the Wei, Jin, Southern, and Northern Dynasties, the dry climate led to the predominance of civil structures that prioritized wind and sand prevention, as well as indoor warmth. The spatial layout of these buildings was relatively enclosed, with flat roofs and thick walls to maintain internal temperatures. In the Sui and Tang dynasties, the warmer and more stable climate allowed for a gradual increase in the spatial scale of individual buildings. Roof slopes became steeper, and building layouts tended to be more open, with walls designed to be more transparent. The addition of open areas such as corridors improved indoor and outdoor ventilation and lighting, reflecting the milder climatic conditions of the time. During the Song, Liao, and Jin dynasties, as the climate grew colder, the spatial forms of individual buildings once again shifted to prioritize cold prevention and insulation. Walls thickened, roof slopes became smaller, and the overall enclosure and practicality of buildings were enhanced to combat the harsher environment. By the Yuan, Ming, and Qing dynasties, the increasingly dry and cold climate led to a greater emphasis on windproofing and insulation in individual buildings. The use of bricks, tiles, and other durable materials became more widespread, and space design focused on internal and external separation, as well as privacy. Overall, the spatial form of individual buildings in the Hexi Corridor exhibits a cyclical pattern: transitioning from enclosed to transparent and then back to enclosed designs in response to climate change; and roof slopes showing a trend of decreasing, then increasing, and finally decreasing again. This architectural evolution underscores the region’s continuous adaptation to its changing environment (Fig. 12).

Fig. 12

Comparison of spatial form evolution between group buildings and individual buildings.

From the perspective of climate change, the spatial forms of residential buildings, temples, government offices, and tower buildings in the Hexi Corridor region have evolved in ways that reflect adaptation to climatic conditions across different historical periods. During the Wei, Jin, Southern, and Northern Dynasties, the climate was relatively dry and cold. Residential buildings were simple, typically adopting a courtyard-style layout with clear functional differentiation and strong defensive features. Temple buildings were compact, with thick walls designed to prevent wind and sand while maintaining warmth. Government buildings emphasized practicality and defensive functions, reflecting the need for protection in a harsh environment. In the Sui and Tang dynasties, as the climate became more stable and warmer, building spaces gradually expanded. Temples and government offices, in particular, began to incorporate more stone and wood, resulting in more open and spacious designs. Courtyards and corridors were added to enhance ventilation and lighting, improving the overall functionality of these structures. Residential buildings also saw an increase in scale, with more detailed functional differentiation and a greater emphasis on comfort, reflecting the milder climatic conditions of the time. During the Song, Liao, and Jin dynasties, the climate turned colder, prompting a greater focus on insulation in residential, temple, and government buildings. Exterior walls were thickened, and roof designs were adapted to better suit the cold climate, enhancing the buildings’ airtightness and cold resistance. Temples and tower buildings became more prevalent during this period, combining defensive and religious elements. Tower buildings, especially in border areas, took on stronger military functions, reflecting the need for both protection and spiritual solace in a challenging environment. By the Yuan, Ming, and Qing dynasties, the climate had grown even colder, leading to further adaptations in architectural design. Residential buildings, temples, government offices, and tower buildings placed greater emphasis on windproofing, thermal insulation, and seismic resistance. The use of brick and stone materials became more widespread, and spatial layouts increasingly separated interior and exterior spaces. Courtyards and gardens were designed with greater attention to the integration of landscape and daily life, resulting in a more mature and refined architectural style⁴⁵.

Overall, the impact of climate change on the spatial forms of different types of buildings in the Hexi Corridor is evident in the changes in building size and scale, the optimization of functional design, and the gradual enhancement of practical features such as defense and insulation. This evolution underscores the region’s architectural resilience and adaptability in the face of shifting environmental conditions (Fig. 13) .

Fig. 13

Comparison of spatial form evolution of different building types.