The Australian Site Network

Summary

There are currently 32 trials listed as active participants in the Australian Network of Long-Term Agronomic Experiments. The primary objective of this network is to establish a central database of information for use by researchers actively involved in developing and testing soil and plant models for sustainable wheat and livestock production. The network sites are the primary source of data for two federally funded soil carbon storage and turnover studies to determine the long-term impact of agricultural management on soil C dynamics in agro-ecosystems. The three oldest cropping trials in the network (Dooen, Glen Innes and Urrbrae) range from 70 to 83 years in duration and are found on markedly different soil types (black clay loam, grey clay, and sandy-loam respectively). However, the physically protected pool, as measured by high energy ultra-violet photo-oxidation, has been consistently measured as 31% of the total soil organic carbon pool for samples taken during the course of the trials from a wide variety of crop and ley farming treatments. The majority of this protected organic matter fraction has been identified by ¹³C NMR as charcoal, a largely inert form of carbon.