Impacts of floating urbanization on water quality and aquatic ecosystems: a study based on in situ data and observations

Abstract

Floating urbanization is a promising solution to reduce the vulnerability of cities against climate change, population growth or land scarcity. Although this type of construction introduces changes to aquatic systems, there is a lack of research studies addressing potential impacts. Water quality data collected under/near floating structures were compared with the corresponding parameters measured at the same depth at open water locations by (i) performing scans with underwater drones equipped with in situ sensors and video cameras and (ii) fixing two sets of continuous measuring in situ sensors for a period of several days/months at both positions. A total of 18 locations with different types of floating structures were considered in this study. Results show small differences in the measured parameters, such as lower dissolved oxygen concentrations or higher temperature measured underneath the floating structures. The magnitudes of these differences seem to be linked with the characteristics and type of water system. Given the wide variety and types of water bodies considered in this study, results suggest that water quality is not critically affected by the presence of the floating houses. Underwater images of biofouling and filter feeders illustrate the lively ecosystems that can emerge shortly after the construction of floating buildings. HIGHLIGHTS Floating buildings introduce changes to aquatic systems that can affect the environment negatively, but also generate various benefits and opportunities for ecology development.; Research studies addressing the impact of floating structures are scarce despite their importance to support water managers in policy making.; Although the results from several different study locations show lower dissolved oxygen concentrations and higher temperature measured underneath the floating structures, the magnitude of the detected differences suggest that water quality is not critically affected by the presence of the floating houses.; Long-term continuous measurements illustrated daily and seasonal variability of values and differences, as well as their relationship with weather conditions.; Underwater images show an impression of the lively ecosystems that can emerge shortly after the installation of floating buildings.;

Keywords

• ecosystems
• environmental impacts
• floating urbanization
• monitoring
• water quality