Laboratory for microbial diversity

Micro-organisms such as bacteria and fungi play an essential role in environmental processes. They perform mineralisation of nutrients and can biodegrade pollutants in soil and groundwater, but they can also attack foundation piles and pipelines. The Deltares Laboratory for Microbial Diversity conducts research into the microbiological composition of a system and how that determines the functions of the soil system.

Research

The laboratory analyses biodiversity and identify how the microbiological composition changes as a result of variations in geochemical conditions and human activities. This allows us to answer questions such as: what effect do anthropogenic activities have on biodiversity and the functioning of the system? Microbiological populations in general are very diverse, and therefore we concentrate also on detecting functional groups such as denitrifying, methanogenic and dechlorinating bacteria. The research is along four main lines:

• Identification dominant micro-organisms
• Detection of functional micro-organisms (soil decontamination / bioremediation)
• Shifts in population composition
• Development of new detection methods

In addition to a fully-equipped microbiological laboratory (ML-I), Deltares also has an ML-II classified laboratory, which makes it possible to apply molecular genetic techniques to environmental samples and to work with pathogenic micro-organisms.

Commissions and projects

• Aquaterra is a project in the EU's Sixth Framework Programme that is intended to provide better understanding of the effects of climate change on river systems. Deltares is investigating the impact of primary and secondary effects (changing temperature, increasing water levels and the transport of polluted sediment) on the microbial diversity and functionality of river sediment.
• Specific micro-organisms could possibly be used as indicators for particular soil properties. In the context of the geoscientific characterisation of the subsoil, an exploratory study commissioned by the government is being carried out into the correlation between geochemical soil conditions and microbial diversity.
• SmartSoils: It has been shown that micro-organisms are able to consolidate loose sand into a cohesive stony mass, using a number of specific enzymes to do so. Deltares is researching this microbiological process so it can be optimised and is measuring accurately how many of the present micro-organisms contain those specific enzymes.
• Aeration with oxygen is often used to prevent blooms of cyanobacteria in lakes. Deltares is investigating the effect this has on microbial diversity and the population composition of the micro-organisms present. The study is being carried out in collaboration with the Rijnland district water control board and the local commercial recreation industry.