Rab Abdur - International Union of Soil Sciences
Rab Abdur - International Union of Soil Sciences
Rab Abdur - International Union of Soil Sciences
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The relationships between clay content and FC and PWP found in this study are consistent with those<br />
reported for other soils (e.g. King and Stark 2005; Minasny et al. 1999; Iqbal et al. 2005). For example, Iqbal<br />
et al. (2005) found greater values <strong>of</strong> volumetric water content at paddock locations where the percentage clay<br />
content was high; an indication <strong>of</strong> the greater water holding capacity <strong>of</strong> soil micropores between clay-sized<br />
particles. Minasny et al. (1999) found a positive non-linear relationship between clay content and FC and<br />
PWP. The equations developed in this study can be used to predict FC and PWP for similar soil types. These<br />
samples used in this study (N=72) cover a wide range in soil textural composition but limited range in<br />
organic carbon content. Therefore, further research, covering wide range <strong>of</strong> landuse systems, soil types and<br />
climatic conditions, is required to improve these predictive equations.<br />
Conclusions<br />
FC, PWP and PAWC were found to be significantly higher for GV followed by HYC and RS. FC was<br />
affected by both clay content and organic carbon (OC) content but PWP was only affected by clay content<br />
but not by OC. The developed equations can be used to predict FC and PWP for similar soils elsewhere.<br />
However, further research is needed to validate/improve the predictive models for a wider range <strong>of</strong> organic<br />
carbon content, soil types, soil texture and climatic conditions.<br />
Acknowledgement<br />
This research was jointly funded the Grains Research and Development Corporation and the Victorian<br />
Department <strong>of</strong> Primary Industries. The authors would like to thank A. Weidemann, I. McLelland, M.<br />
McLelland and R. Dunlop for the use <strong>of</strong> their paddocks.<br />
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© 2010 19 th World Congress <strong>of</strong> <strong>Soil</strong> Science, <strong>Soil</strong> Solutions for a Changing World<br />
1 – 6 August 2010, Brisbane, Australia. Published on DVD.<br />
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