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• PIV and the PCA are used to measure simultaneously the surface velocity field and pollutant concentration. • DBM D2Q16 and LBM D2Q5 are used to simulate the velocity and concentration fields. • Effects of the vegetation's density on water depth, velocity field and pollutant transport are discussed. Transport phenomena are crucial components of the biological and chemical processes that govern fluvial environments. The presence of vegetation along rivers plays a significant role in affecting the flow velocity, which becomes unevenly distributed, and consequently is an important factor that can affect longitudinal and transversal dispersion and mixing of pollutants. Therefore, in this study, to provide a better understanding and further insights of the velocity field and the pollutant dispersion in open channels partially covered by sparse vegetation and dense vegetation, an experimental campaign is presented to compare them with the no-vegetation scenario. Novel datasets are produced by applying the Particle Image Velocity (PIV) and the Planar Concentration Analysis (PCA) technologies, which were used to measure simultaneously the surface velocity field and pollutant concentration map within the open channel tested. Results obtained have been used to calibrate and validate a numerical model designed to simulate velocity fields (via Discrete Boltzmann Model D2Q16) and pollutant concentration maps (via the Lattice Boltzmann model D2Q9). Results have shown that as the density of vegetation increases, the flow velocity in the vegetation zone decreases while the velocity in the no-vegetation zone increases. So, the velocity gradient in the transition zone increases accordingly. Besides, the water surface difference between inlet and outlet is higher as the density increases. Finally, the simulated results have been compared with corresponding experimental data and good agreements have been achieved, which indicates that the model developed can accurately predict features that were observed and measured within the experimental facility. [ABSTRACT FROM AUTHOR]

Based on the theory of landsenses ecology, this paper makes a detailed analysis of the architecture pattern of 'The House of Hundred Rooms'(HHR) in the East Dragon Village, a traditional ancient Chinese village, so as to provide a reference for the research on reasonable land use and sustainable development in modern times. By the principle of the vein-compliance in orientation and bearing in landsense creation, the paper analyses the causes of the north-facing feature and the 'counter-tradition' room setting feature lie in the architectural pattern of HHR, revealing that people's psychological perceptions of orientation and bearing is distinct from the physical one. It points out these features of this building complex are the results of man's active adaptation to nature on the basis of respecting nature, which together manages to form a process of constructing the harmonious relationship between man and nature during land use. By the principle of the multiscale (trans-scale or cross-scale) spatiotemporal combination in landsense creation, the paper continues to analyze on the pattern of HHR and finds that it has both the function of cultural inheritance and the innovation of adaptation to new environment, which can promote the protection of historical and cultural elements during the course of development, and bring reference for the realization of sustainable development from the perspective of contemporary historical and cultural heritage protection. [ABSTRACT FROM AUTHOR]

Thermal comfort in outdoor spaces is of vital importance to human health and well-being, and affects the livability of cities. In a humid-hot region with elevated temperatures, it is difficult to improve the thermal experience of urban residents by changing objective conditions such as the microclimate. This study created a set of experience indices in different dimensions including visual, auditory, and olfactory perceptions and psychological cognitions, to explore the influencing factors and mechanisms of visitor's thermal comfort in an urban park. We found that visual, auditory, and olfactory experience indices and psychological cognition indices were both strongly correlated with thermal comfort (Pearson correlation coefficients were above 0.3). By analyzing a survey data with a structural equation model, we found that Visual, auditory, and olfactory experiences have a complete, mediating effect on thermal comfort. Explicitly, visual, auditory, and olfactory perceptions affect thermal comfort through two mediating variables: thermal sensation and psychological cognitions. In turn, thermal sensation and psychological cognitions have a direct effect on visitor's thermal comfort. Psychological cognitions has the largest direct effect on thermal comfort. Quantitatively, a 1-unit increase in psychological cognitions produces an increase of 0.601 units in thermal comfort. A potential approach is to improve multisensory modalities that affect necessary sensory perception and psychological cognitions of visitors. The findings of this study provide a valuable reference for the planning and design of recreational spaces in humid-hot regions and for the studies of outdoor thermal comfort. [ABSTRACT FROM AUTHOR]

High PM 2.5 concentration threats ecosystem functions but limited quantitative studies have recognized PM 2.5 pollution as an individual stressor in evaluating ecological risk. In this study, we applied a machine-learning-based simulation model incorporating full-coverage satellite-driven PM 2.5 dataset to estimate high-resolution ground PM 2.5 concentration for the Golden Triangle of Southern Fujian Province, China (GTSF) in 2030 under two Representative Concentration Pathways (RCPs). Based on the simulation output, the ecological risk's spatiotemporal change and the risk for different land cover types, which were caused by PM 2.5 pollution, were assessed. We found that the PM 2.5 levels and ecological risk in the GTSF under RCP 4.5 would be reduced while those under RCP 8.5 would continue to increase. The regions with the highest ecological risk under RCP 4.5 are the most urbanized and industrialized districts, while those with the highest ecological risk under RCP 8.5 are of the highest rate in urbanization and the greatest decrease in planetary potential layer height. For both base years and 2030 under two RCPs, the ecological risk on developed land is the highest, while that on the forest is the lowest. Our study can provide useful information for environmental policy risk assessment. • Model simulations captured spatio-temporal trends of PM 2.5 in 2030 under two RCPs. • We assessed the ecological risk of PM 2.5 considering regional disparities. • The variation of land cover, population and climate change will induce polarized ecological risk under two RCPs. • The developed land in the GTSF has the highest ecological risk and the forest the lowest. [ABSTRACT FROM AUTHOR]