Towards protecting and improving building stones through microbial manipulation of pore structure

NWO-Vici project BugControl


Physical, chemical and biological weathering has a profound impact on the Earth’s landscape and on building infrastructure. Rock and masonry are constantly damaged and disaggregated by chemical reactions, water infiltration and temperature changes. Strengthening efforts to protect and safeguard the world’s cultural and natural heritage is one of the United Nations’ Targets for Sustainable Cities and Communities in the 2030 Agenda for Sustainable Development.

Fluids are a major driver of rock weathering: they trigger, among others, dissolution, precipitation, frost and salt weathering. The key to manipulating weathering lies in understanding and controlling fluid flow within the internal pore structure of rocks and thereby influencing the related pore-scale processes. While microbial organisms are generally known to alter rock surfaces, some actually display physiological capabilities that have beneficial effects on rock properties due to their production of bio-cement, gas and acids. Before we can harness these beneficial effects, we must first study how these organisms impact fluid flow at the pore scale.

The aim of BugControl is to determine the potential of microbial colonization for use in building stone conservation. Fundamental research will be performed to: a) understand fluid-rock interaction in the presence of microbial organisms using advanced 4D imaging; b) predict the impact of microbial organisms on rock properties; c) develop smart bio-conservation strategies.
 
Understanding bio-manipulated pore-scale processes inside rocks is the missing link to predict and influence weathering. For the first time, the microbial effect will be monitored at the pore scale using high-resolution 4D imaging. Exploiting the resulting 3D images as input for pore network modelling and upscaling of behaviour to macroscale will allow BugControl to influence rock weathering via new bio-conservation strategies. This can directly be implemented to protection of cultural heritage, but also in environmental geology, hydrogeology, CO2 sequestration strategies and others.

Research Team