Does the presence of glomalin relate to reduced water infiltration through hydrophobicity?

The resilience and stability of the physical structure of soil impacts directly on all soil processes, mediating microbial activity and defining the flow pathways between the soil ecosystem, waterways and the atmosphere. The effect of the presence of the glycoprotein glomalin exuded from Arbuscular Mycorrhzal (AM) fungi, on soil hydrophobicity is presented. A possible role for glomalin as improving soil structural stability is important in the context of soil protection. Using total glomalin, together with measurements of soil hydrophobicity, we investigate the spatial correlations between the two measurements in the presence and absence of pea roots. Whilst AM fungi were visible within roots (up to 52% root length colonization), no differences in glomalin concentration between planted and unplanted controls were observed. The presence and amount of glomalin did not correspond to the presence or level of hydrophobicity in soil. We discuss these results in relation to AM fungal-glomalin interactions, soil structure and root exudation.