A survey of total and dissolved organic carbon in alkaline soils of southern Australia

• DOI: 10.1071/sr16237
• Publication Date: 2017-02-08T17:16:34Z
• Authors: G. K. McDonald; E. Tavakkoli; D. Cozzolino; K. Banas; M. Derrien; P. Rengasamy
• Keywords: Soil carbon; Alkali soil

Dissolved organic carbon (DOC) is important to microbial activity and nutrient cycling, its concentration sensitive pH. Despite the importance of alkaline soils agricultural production in southern Australia, few studies have documented concentrations soil (C) DOC or described effects properties management practices on these soils. A survey 33 paddocks from Eyre Peninsula mid-North regions South Australia north-western Victoria demonstrated significant variation pH, C DOC. Carbon stocks surface 30cm were 40–55tC/ha lowest Victoria. Soils had higher top 20cm than Principal component analysis suggested was increased by high electric conductivity exchangeable Na, reduced Ca clay content. Mid-infrared Fourier transform infrared spectroscopy identified regional differences composition C, with amounts charcoal Farm little effect but influenced Grain yield inversely related across within which appeared be intensity cropping having opposite influences Compared international data, relative amount and, contrast many previous studies, all depth.