Vegetation and soil patterning in semi-arid mulga lands of Eastern Australia [New South Wales]

Vegetation and soil patterns across a 200 ha semi-arid site 40 km north-west of Louth, New South Wales, are described using plant cover data from line transects and soils data from points, sampled systematically (50 m intervals) across the site. A patterned sequence of alternating groves and intergroves with 3 vegetation types was identified: an Eragrostis eriopoda savanna occurring on runoff slopes from low ridges, with a Monachather paradoxa savanna occurring at the toe of these runoff slopes (intergroves), followed by an Acacia anuera woodland. Data on landform, microtopography, and hydrological features indicate that the grove-intergrove pattern is maintained by differential erosion-deposition processes similar to the dynamic erosion-transfer-sink geomorphic systems described for Central Australia. Patterning in mulga lands is more extensive geographically, and has a wider climatic range, than previously reported.