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Disclaimer:
Any recommendations, suggestions or opinions contained in this publication do
not necessarily represent the policy or views of the Grains Research and
Development Corporation, the Cooperative Research Centre for Greenhouse
Accounting or the CSIRO. No person should act on the basis of the contents of
this publication without first obtaining specific, independent professional advice.
The Grains Research and Development Corporation, the Cooperative Research
Centre for Greenhouse Accounting and the CSIRO will not be liable for any loss,
damage, cost or expense incurred or arising by reason of any person using or
relying on the information in this publication.
This report is part of the GRDC project Residue management, soil organic
carbon and crop performance (CSO 00029) with Jan O. Skjemstad as principal
supervisor. The report was produced by Evelyn S. Krull, Jan O. Skjemstad and
Jeffrey A. Baldock (CSIRO Land & Water and Cooperative Research Centre for
Greenhouse Accounting) with the aims to a) provide a detailed literature review
on the effects of organic matter on soil functions, b) ensure that no similar work
paralleling the approach of the GRDC project has been undertaken in the past
and c) to add to the on-going research on soil organic matter undertaken by the
CSIRO Land & Water and the CRC for Greenhouse Accounting.
© Cooperative Research Centre for Greenhouse Accounting
GPO Box 475 Canberra ACT 2601
Phone +61 2 6125 4020
http://www.greenhouse.crc.org.au
ISBN 0-9579597-4-5
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Contents:
page
1. Summary ………………………………………………………………………. iii
2. Introduction:
a. What is soil organic matter? ………………………………………… 1
b. Soil quality and the role of SOC …………………………………….. 1
c. Do generic critical threshold values exist for SOC? .……………… 2
d. Overview of principal functions of SOM in soils ……………………. 6
3. Soil carbon fractions and SOC analytical methods ………………………... 7
4. Role of SOM on soil functions
a. Phy