Assessment of erosion rates from microphyte-dominated calcareous soils under rain-impacted flow

摘要: Intact soil monoliths with surfaces of varying microphytic crust cover were collected from a calcareous earth in semi-arid belah–rosewood woodland near Wentworth south-western New South Wales. Monoliths tested for their susceptibility to erosion by rain-impacted flow using laboratory rainfall simulator. The erosive stress applied each surface was controlled the depth between 4 and 8 mm whilst maintaining velocity 25 mm/s 2·7 raindrops falling 11·2 m at average intensities 65 mm/h. Increasing crusts on resulted significant (P = 0·001) reduction sediment concentration. A linear model incorporating percentage distribution accounted 46% variance erosion. relationship also found coarse fraction (>0·053 mm) 0·012) 4-mm depth. Management practices such as overgrazing, trampling, fire, which reduce this landscape, will lead increased hazard.