Rapid urbanization has caused radical changes in urban climates. As a result, issues related to urban thermal environments have become more prominent. Finding a balance between urban expansion and ...thermal environment quality is key to ensuring sustainable urban development. Taking Dalian City (China) as an example, we used multi-source datasets, including Luojia1-01 nighttime light imagery, Landsat-8, Sentinel-2, and building vector data, to analyze the thermal characteristics of different local climate zones (LCZs). Additionally, the LCZ combination mode with the lowest heat island effect intensity in the human settlements was also investigated. The results showed that the human settlements covered an area of 351.976 km2, with 33.476% corresponding to building LCZs (LCZ1-10) and 66.524% to natural LCZs (LCZA-G). The different LCZs had different thermal environment characteristics, and the UHIA values for the building LCZs were significantly higher than those of the natural LCZs. Additionally, for the building LCZs, the UHIA values for compact building LCZs (LCZ 1–3) were also significantly higher than those for open and spare building LCZs. With the current settlement area and population size, the most appropriate LCZ layout model for the study area was LCZ5 + LCZ6 + (LCZ7+LCZ8+LCZA + LCZC + LCZD + LCZE + LCZG), which had areas 28.585, 57.170, 57.170, 28.585, 54.236, 54.236, and 54.236 km2, respectively. This layout model had the smallest UHIA value (11.654 °C), and urban planning according to the above ratio can alleviate the UHI effect in different cities.
•Comprehensive analysis of thermal environment characteristics and population.•Human settlements were investigated using high resolution Luojia 1-01 NTL data.•Accumulated amounts of urban heat island intensity (UHIA) were investigated.•Model with lowest UHIA had a limit on population and total area of human settlement.
Chinese Journal of Catalysis is co‐sponsored by the Dalian Institute of Chemical Physics, Chinese Academy of Sciences and the Chinese Chemical Society, and it is currently published by the Elsevier ...group. This monthly journal publishes in English timely contributions of original and rigorously reviewed articles in all fields of catalysis. The journal publishes Reviews, Communications, Articles, Highlights, Perspectives, and Viewpoints written in English or in English supplemented with an extended Chinese abstract.
•Surface temperature characteristics are affected by many factors, such as building form and land use.•The spatial regression model can effectively explain the relationship between LST and each ...impact factor.•Rational planning of community land resources and landscape features can effectively mitigate urban heat islands.
Owing to increasing population densities and impervious surface areas, heat island effects increasingly dominate urban environments and hinder sustainable development. The urban spatial form plays an important role in mitigating urban heat islands. Taking Ganjingzi District, Dalian, as an example, this study considered urban spatial form at the community scale using spatial autocorrelation and spatial regression methods to explore 2003–2018 spatial and temporal differentiation characteristics and driving factors of Land Surface Temperature (LST). The LST of each community showed a gradually increasing trend; high values (>30°C) were concentrated in central and eastern areas; low values were (<25°C) was concentrated in the south and west. LSTs were influenced by spatial variables (e.g., land use); however, building form was only weakly related to LST. The global autocorrelation Moran’s I value for LST exceeded 0.7, indicating strong positive correlation in terms of spatial distribution. H-H and L-L LISA values were distributed in central and southern areas, respectively. The spatial error model (SEM) was a better fit than the spatial lag (SLM) or ordinary least squares models (OLS) and was used to explore these relationships. This study focuses on community surface temperature and hopes to provide a valuable reference for community planning, resource allocation and sustainable development.
•Based on monitoring data, the impact of the reclamation was retrospectively analyzed.•Combined with the project and regional character, ecological restoration measures are proposed.•The ...effectiveness of marine ecological restoration was verified by mathematic model.
Reclamation activities should be combined with the actual functional requirements of engineering sea areas. The contradiction between major reclamation activities and Marine ecological protection should be coordinated according to the local natural conditions, so as to put forward reasonable and feasible ecological construction plans.
This paper takes the Taiping Bay reclamation project of Dalian Port as an example, and based on the analysis of the impact of the regional historical reclamation on the coastline, hydrodynamics, water quality, marine ecological environment, and other factors. Combined with the results of numerical simulation, the realization and effectiveness of the marine ecological restoration and compensation scheme are described in detail. Although the reclamation project will bring about ecological and environmental problems, it is still an effective means to "effectively alleviate the contradiction between land supply and demand in coastal areas, expand development space and promote rapid economic development".
This paper puts forward suggestions to realize the coordinated development of marine economy and ecological protection from the reclamation land control policy and ecological restoration measures.
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•The spatial distribution of three-dimensional morphological characteristics of Dalian city was studied.•Land surface temperature (LST) in Dalian shows a strong spatial positive correlation.•Building ...density has the most significant effect on land surface temperature (LST).•Building density affects the thermal environment by influencing wind speed.•When the building density is less than 0.6, the wind speed increases with the building density increasing.
Variation in urban microclimate is closely related to the three-dimensional characteristics of cities. To reveal the influence of urban spatial forms on land surface temperature (LST), the spatial distribution of LST and five urban morphology indicators were analyzed, namely floor area ratio (FAR), plot ratio (PR), absolute rugosity (Ra), mean aspect ratio (λc), and sky view factor (SVF). Based on correlation analysis and numerical simulations, the influence of three-dimensional characteristics on the urban thermal environment of Dalian, China was then analyzed. The results showed that in Dalian, LST ranged from 23.2–50.7 °C, and Moran's I was 0.94, indicating that LST presents a strong spatial positive correlation. The buildings in the study area were mainly multi-story and high-rise buildings and mostly distributed in a medium-density area. LST exhibited the highest positive correlation (correlation coefficient = 0.569) with FAR and was negatively correlated with SVF (correlation coefficient =−0.270). The simulation results showed that in the medium density range (FAR <0.6), an increase in FAR changed the wind speed, thereby affecting the urban thermal environment. The results demonstrate the influence of urban morphology on the thermal environment and provide scientific ideas for future planning and construction of “cool cities”.
•The relationship between land type change and carbon stock change was analyzed.•Analyze the spatial and temporal changes of carbon storage from 2000 to 2030.•The carbon density data were corrected ...for precipitation and temperature in Dalian.•Carbon storage has a faster recovery under the scenario of ecological protection.
Carbon storage in terrestrial ecosystems varies with land use changes, and exploring the impact of land use changes on carbon storage in regional terrestrial ecosystems is important for maintaining regional carbon balance. Data on Dalian City’s land use types from 2000 to 2020 are used in this research, to evaluate the spatio-temporal evolution of carbon storage in Dalian. Furthermore, with the scenarios of urban development, natural development, cultivated land protection, and ecological protection in 2030, this study combines the PLUS and InVEST models to emulate the dynamic adjustment at land-use types and the spatio-temporal evolution regarding carbon storage in Dalian City. The investigation shows that: 1) The carbon storage of terrestrial ecosystem in Dalian has been altered as a consequence of changes in land use, and now it shows a general decline during 2000–2020, with reductions amounting to 5.39 × 106 t. 2) From 2000 through 2020, Dalian’s land resources that are utilized for farming, forestry, and grassland decreased to different degrees. The total construction land area increased by 796.47 km2, or 6.38 %, whereas there has been no substantial improvement in water or unused land. 3) The carbon storage reduction in 2030 in comparison to 2020 for the natural development, cultivated land protection, and urban development scenarios, among which the urban development scenario was the largest, was 1.36 × 106t.It suggests that the rapid rate of urbanization and expansion of constructionlandis an important cause of the decline in carbon storage. 4) The cultivated land protection scenario (CPS) yields the smallest reduction of 6.50 × 105t. The structure of Dalian’s land use type is optimum under the ecological protection scenario (EPS), as seen by the 3.90 × 105t increase in carbon storage under this scenario. It speeds up the rate of recovery of carbon storage and improves the function of carbon sinks in urban terrestrial ecosystems. Hoping to provide the reference to decision makers for ecosystem carbon storage optimization from the view of land use, which is vital for making future land use policies and realizing the “dual carbon” strategic goal.
The article reflects the results of the research work conducted by the authors within the framework of the scientific project: "Architecture of Banking and Consular Institutions in Manchuria in the ...Late 19th - Early 20th Century." In a brief historical essay, we outline the reasons for the creation of the Russo-Chinese Bank and its activities in the northeast of China. Photographs and archival materials are used to appreciate the preserved and lost buildings of the bank’s branches in Dalian (Port Arthur and Dalny), as well as two unrealized projects drawn up by the German architect G.Yu. Junghendel at the beginning of the 20th century. The study identifies the stylistic and spatial planning features of the Russo-Chinese Bank’s buildings and their place in the general architectural landscape of the Kwantung Peninsula during the period when this territory was in Russian possession.
Water scarcity tends to be aggravated by increase in water demand with the trend of socio-economic development. Thus, non-stationary characteristics of water demand should be identified in water ...resources allocation (WRA) to alleviate the potential influences from water shortages. In this study, a Copula-based interval linear programming model was established for regional WRA. Through combining correlation analysis and an interval linear programming model, this model can: 1) identify interactions between water demand and socio-economic development levels based on Copula functions, 2) explore variations in water shortage with consideration of multiple risk tolerance levels of decision-makers based on Copula sampling, and 3) obtain desired strategies for WRA through an interval linear programming model. Also, Dalian City in China was selected as a case study area to verify the effectiveness of the model for WRA to five water users (i.e., agricultural sector, industrial sector, public service sector, domestic residents, and ecological environment). Considering multiple tolerance levels of decision-makers to water shortage risk, three scenarios (i.e., S1 to S3), indicating 20%, 40%, and 60% of their low, medium, and high tolerance levels, were proposed. The results showed that the correlation between the amount of water demand and indicators of socio-economic development can be described by Clayton and Gaussian Copula functions. The total water supply of Dalian in 2030 would increase by 2.06%–2.65%, compared with the one in 2025. The allocation of water resources across districts was influenced by varied water demand, energy consumption, and risk tolerance levels. Compared with the amount of water allocation in 2025, the contribution of transferred water sources would increase by 6.71% and 7.04% under S1 and S2 in 2030, respectively, and decrease by 14.31% under S3. With the increase of risk tolerance levels of decision-makers, the amount of water supply in Dalian City would gradually decrease.
•A Copula-based programming model is developed for water allocation management.•Decision-makers' tolerance to water shortage risk is incorporated.•Variations of water demand along with socio-economic development are identified.
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•The kinematic model of the up-soft/low-hard stratum was established.•The appropriate construction method was adopted.•Tunnel arch excavation is the main reason of ground ...settlement.•The slip failure surface and ground settlement curve were determined.•Eighty percent of the load is borne by the initial support.
The excavation of a shallow large-span metro tunnel in an up-soft/low-hard rock stratum restricted by a rock mass requires knowledge of the stratum kinematic mechanism to adopt an appropriate construction method to control the surface settlement and ensure structural safety. The purpose of a kinematic analysis is to predict the state of stratum collapse based on the nonlinear Hoek-Brown failure criterion and the upper bound theorem. The rock mass deformation and the supporting structural mechanics characteristics of the tunnel under different excavation methods are studied using numerical simulations. The Xinggongjie Station tunnel on the No. 1 Line of the Dalian Metro is used as an example. Furthermore, the ground surface settlement, the internal displacement of the surrounding rock mass and the stress on the supporting structure are monitored during the construction period. The accuracy of the theoretical kinematic model and the rationality of the selected excavation method are verified by comparing the theoretical results with the field monitoring results. The study shows that the slip failure surface and ground settlement curve can be accurately determined using the kinematic model. Different excavation sequences result in differences in the surface subsidence, and the most favourable sequence for restricting the subsidence is to excavate the arch-side pilot first and the middle pilot last. The rock mass deformation and the surface subsidence are acceptable according to field monitoring under this excavation sequence. The load ratios of the surrounding rock mass borne by the initial support, which is the primary bearing structure of the tunnel, at different monitoring points are greater than 80%. The proportion of the secondary lining is approximately 20%, which is the safe reserve of the tunnel. The tunnel has been demonstrated to be safe; it has been placed into service and has operated well.
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