Floating Microbial Mass for Reservoir Evaporation Control and its Effect on Soil Mineralogy

Background: The combined application of microbiology, biotechnology and hydrology has the potential to address a multitude of issues related to water contamination, water conservation and waste management. This research aims to contribute to water conservation efforts through ecological and environmental preservation. In Gujarat, India, there are numerous large reservoirs (water bodies) where millions of liters of water are lost due to higher temperature and evaporation. To mitigate this loss, it is crucial to identify, process and apply natural microbes found in these water bodies in a way that maximizes reduction in evaporation. Methods: To achieve our objective, we developed a laboratory-scale experimental setup (Class A pan evaporimeter) to measure evaporation rates under varying humidity and temperature conditions. We used the serial dilution and spread plate methods to isolate microorganisms from water and soil samples and then grew selected microorganisms (Bacillus megaterium, Bacillus subtilis) in slants to minimize water loss. These isolated floating microbes were then placed in the Class A pan evaporimeter and the evaporation loss was periodically measured under different temperature and humidity levels. We also evaluated the sustainability of these floating microbes and their ability to improve water retention capacity before and after treatment. Additionally, we used X-ray diffraction to assess the effect of these microbes on the mineral composition of the reservoir bed. Result: A recent study revealed that the use of floating microbes can effectively reduce evaporation loss by up to 30-40% overall. Additionally, this method can help maintain the quality of water, sediment composition and the overall ecological balance for aquatic animals.