
%0 Journal Article
%A Kinnell, PIA 
%A Chartres, CJ 
%A Watson, CL 
%T The effects of fire on the soil in a degraded semiarid woodland .II. Susceptibility of the soil to erosion by shallow rain impacted flow
%J Soil Research
%D 1990/10/01
%V 28
%N 5
%P 779-794
%K 
%R https://doi.org/10.1071/SR9900779
%U https://www.publish.csiro.au/paper/SR9900779 
%X Small (500 by 250 by 100 mm) soil monoliths collected from experimental plots subjected to various fire frequencies in a semi-arid woodland near Coolabah, N.S.W., were tested for their susceptibility to erosion by rain-impacted flows under laboratory conditions. In the tests, the erosive stress applied to the soil surfaces was controlled by using drops of uniform size (2.7 mm) falling 11.2 m onto flows whose depths were controlled between 1 and 2.7 drop diameters. Experimental data and thin-section observations showed that cryptogams provide a high degree of protection against erosion. Sediment concentration (measured in g L-1) from cryptogam-covered plots was considerably less than that from both bare-crusted surfaces and surfaces dominated by depositional material. Surfaces with cryptogamic crusts were generally free of debris, but showed only minor signs of erosion, whereas bare-crusted and depositionary surfaces suffered pronounced lowering and tended to disintegrate. Because increasing fire frequency reduces the spatial distribution of the cryptogamic cover on the soil surface in the semi-arid woodlands, increasing fire frequency must increase the erosion hazard. 
