Comparison of the influences of different ventilation corridor forms on the thermal environment in Wuhan City in summer.

The ventilation corridor is an essential element in urban planning and design to improve the climate and environment. In this paper, four forms of two ventilation corridors were set up in the southeast of Wuhan City based on its urban planning outline to quantitatively study the influences of different ventilation corridor forms on the urban thermal environment in summer. The urban micro-meteorological environment was simulated using the next-generation mesoscale Weather Research and Forecast (WRF) model coupled with an urban canopy model (UCM). Critical time-dependent meteorological values were extracted and plotted, including temperature and wind difference fields, average temperature at 2-m height, average wind speed at 10-m height, and surface energy flux. By conducting a comparative analysis of the quantitative results, the ventilation corridors in construction land are arranged at intervals in the upwind position of the city in summer, which can slightly adjust the thermal environment of the central area of the city, and have an effective regulation on the temperature of the corridors and surrounding areas during the daytime. Especially at 15:00 pm when the temperature is at its highest during the day, the temperature can be reduced by 0.8 °C. Compared to other corridors, the wind speed in and around the corridor is the strongest 11 h a day. Due to the internal arrangement of construction land, this corridor form is more advantageous in the urban land utilization. After considering comprehensively, the ventilation corridor form with construction land arranged at intervals is the preferred corridor form in the southeast of Wuhan. The experimental results can provide quantitative reference for the layout of ventilation corridors in hot inland cities located in central China.

In Situ Continuous Measurement of Salinity in Estuarine and Coastal Sediments by All-Solid Potentiometric Sensors.

Salinity is crucial for understanding the environmental and ecological processes in estuarine and coastal sediments. In situ measurements in sediments are scarce due to the low water content and particulate adsorption. Here, a new potentiometric sensor principle is proposed for the real-time in situ measurement of salinity in sediments. The sensor system is based on paper sampling and two all-solid electrodes, a cation-selective electrode (copper hexacyanoferrate, CuHCF) and an anion-selective electrode (Ag/AgCl). The spontaneous aqueous electrolyte extraction and redox reaction can produce a Nernstian response on both electrodes that is directly related to salinity. This potentiometric sensor allows for salinity acquisition in a wide salinity range (1-50 ppt), with high resolution (<1 ppt), and at a low water content (<30%), and it has been applied for the in situ measurement of salinity and the interpretation of cycling processes of metals in estuarine and coastal sediments. Moreover, the sensor coupled to a wireless monitoring system exhibited remote-sensing capability and successfully captured the salinity dynamic processes of the overlying water and pore water during the tidal period. This sensor with its low cost, versatility, and applicability represents a valuable tool to advance the comprehension of salinity and the salinity-driven dissolved-matter variations in estuarine and coastal sediments.