TY - JOUR
T1 - The influence of organic litter on the erosive effects of raindrops and of gravity drops released from desert shrubs
AU - Geddes, Nicole
AU - Dunkerley, David
PY - 1999/8/1
Y1 - 1999/8/1
N2 - This paper reports on a laboratory study of the effects of water drop impacts on litter and sand splash beneath desert shrubs. Individual drops of 5.7 mm diameter were released from heights of 0.5, 1.0, and 1.5 m (selected to encompass the height range of typical desert shrubs) onto targets of bare or partially litter-covered, saturated fine sand. The natural litter, largely derived from the saltbush Atriplex vesicaria, was collected from desert shrubland sites in western New South Wales (NSW). The drop impacts caused both sand and litter particles to undergo splash displacement. The mass of sand splashed was found to increase with drop fall height, while mass of litter particles splashed did not vary significantly with fall height. Weights of sand moved by airsplash were significantly diminished by surface litter applied at the rate of 200 g/m2. These findings indicate that gravity drops released from desert shrubs may provide both an erosive force beneath these plants, and a means for dispersing litter from the plant base into the surrounding landscape, where litter may continue to affect hydrologic and erosional processes. By restricting splash of mineral particles, litter acts to limit soil splash from beneath shrubs, and in this way may contribute to the persistence of plant mound microtopography that is common in desert shrub-lands. Under open-field conditions, large raindrops delivered in convective showers must cause similar airsplash transport of litter particles, thus playing a role in the distribution of litter within the landscape.
AB - This paper reports on a laboratory study of the effects of water drop impacts on litter and sand splash beneath desert shrubs. Individual drops of 5.7 mm diameter were released from heights of 0.5, 1.0, and 1.5 m (selected to encompass the height range of typical desert shrubs) onto targets of bare or partially litter-covered, saturated fine sand. The natural litter, largely derived from the saltbush Atriplex vesicaria, was collected from desert shrubland sites in western New South Wales (NSW). The drop impacts caused both sand and litter particles to undergo splash displacement. The mass of sand splashed was found to increase with drop fall height, while mass of litter particles splashed did not vary significantly with fall height. Weights of sand moved by airsplash were significantly diminished by surface litter applied at the rate of 200 g/m2. These findings indicate that gravity drops released from desert shrubs may provide both an erosive force beneath these plants, and a means for dispersing litter from the plant base into the surrounding landscape, where litter may continue to affect hydrologic and erosional processes. By restricting splash of mineral particles, litter acts to limit soil splash from beneath shrubs, and in this way may contribute to the persistence of plant mound microtopography that is common in desert shrub-lands. Under open-field conditions, large raindrops delivered in convective showers must cause similar airsplash transport of litter particles, thus playing a role in the distribution of litter within the landscape.
KW - Broken Hill Australia
KW - Soil erosion
KW - Water erosion
UR - http://www.scopus.com/inward/record.url?scp=0033007330&partnerID=8YFLogxK
U2 - 10.1016/S0341-8162(99)00050-8
DO - 10.1016/S0341-8162(99)00050-8
M3 - Article
AN - SCOPUS:0033007330
SN - 0341-8162
VL - 36
SP - 303
EP - 313
JO - Catena
JF - Catena
IS - 4
ER -