Natural nanoparticles in soils and their role in organic-mineral interactions and cooloid-facilitated transport

Mineral nanoparticles are naturally present in the soil and play an important role in several soil processes. This thesis uses a combination of novel analytical techniques, among which Field-Flow-Fractionation, to study nanoparticles in soil and water samples. The results show that nanoparticles can be as small as a few nanometer only and play an important role in the transport of phosphorus and trace metals in the environment. Furthermore, Fe-(hydr)oxide nanoparticles play an important role in sequestration of organic matter and phosphate in soils. The adsorption interactions between phosphorus and organic matter have important implications for the predictions of phosphorus-fertility status of the soil because phosphorus becomes more soluble in soils rich in organic matter. Moreover, this thesis shows that Fe-(hydr)oxide nanoparticles form strong aggregates with organic matter and thereby improve aggregate stability and water retention in soils.