Proteoid root mats bind surface materials in Hawkesbury Sandstone biomantles

Abstract

Sediment yield following bushfire on Hawkesbury Sandstone hillslopes is highly variable and catastrophic stripping of soils often does not occur as anticipated. Proteoid root mats were examined as a potential mechanism for limiting catastrophic stripping of Hawkesbury Sandstone biomantles. It was found that surface and subsurface proteoid root mats were widespread and concentrated in the uppermost portion of the soil profile. The proteoid roots bound mineral soil from the size of clay to gravel. The roots were observed growing up into the leaf litter and bound leaf litter to the mineral soil surface. It is concluded that proteoid root mats bind surface materials in Hawkesbury Sandstone biomantles and are sufficiently widespread to account for the stability of soil materials that appear to be unprotected following bushfire.