Organic Matter and Climate Change

[pe...@swep.com.au]

There has been a lot of research to show that well managed pasture and
no-till cropping can lead to an increase in soil organic matter and
that (globally) changes in soil carbon levels could have significant
impacts on climate change.

Carbon credit stuff aside, what do you think could be done to help
maximise this potential for reducing climate change effects and bring
agriculture to the forefront in combatting this problem?

[Andrew]

Soils hold about 75% of terrestrial carbon and show a greater potential
to sequester much more carbon than trees. Additionally, sequestering
carbon in soils by increasing soil organic matter (SOM) and (in
balanced soils) humus, means higher fertility, higher
yields/productivity, and more sustainable farming on most soils.

It has been shown that many Australian soils have lost up to 80% of SOM
since European colonisation (eg, research on soil erosion and silt
deposits in marshes and swamps in Nth NSW).

Carbon is the 'energiser' of life on earth through photosynthesis;
without adequate SOM, sustainable agriculture is impossible.

It appears that soil cover (constant vegetation), soil mulch/thatch
management and/or grazing management are more critical to catchment
health and sustainability as well as river health than tree cover in
Australia generally.

Dr Christine Jones (http://www.amazingcarbon.com/) has shown rapid
increases (compared with accepted 'natural' increases by academics) in
SOM with various methods of vegetation management including, eg,
pasture cropping (http://www.grainandgraze.com.au/ColinSeis.htm).

Various groups are coming together to support SOM for carbon
sequestration including, eg, Biodynamic Farmers, Holistic Management,
Natural Sequence Farming
(www.abc.net.au/austory/content/2005/s1383562.htm) under the Carbon
Coalition (see below).

There is much academic and scientific dispute over the potential for
SOM increase and its impact on global warming with most saying that SOM
increase is slow and not the best sequestration method despite its
obvious benefits to soil and farming. This is akin to
scientists/specialists arguing whether 1 ppm or 2 ppm is the critical
toxicity level for a chemical rather than acknowleding that the
chemical is toxic and that its may need to be questioned; focusing on
the detail rather than the overall.

However, PM Howard has responded to some lobbying from independent
federal member for New England and ex-farmer, Tony Windsor, to have a
farm/soil person on the 'Carbon Task Force' that he the PM is setting
up.

For the interested, there are various articles and blogs on the
Australian Carbon Coalition website: www.carboncoalition.com.au (set up
by Australian farmers amongst others). A farming couple driving the
Carbon Coalition have recently acquired a carbon trading licence at the
Chicago Board of Trade to service farmers in Australia. You can join
the Coalition and receive an email newsletter/access blogs, etc, if you
like. This is a non-profit, mostly farmer-driven enterprise.

So, pressure is building to have SOM recognised as a suitable
sequestration 'vehicle' for carbon trading and various people are
working on ways to have a tight system for assessing, monitoring and
trading soil carbon on Australian farms.

Regards,
Andrew Jeeves
Earthlink Australia,
Adelaide.

[pe...@swep.com.au]

Thanks Andrew for your comments. You have raised some valuable points.

The continuing research with the Mikhail System has recently been
focusing on two things - ways to improve water use efficiencies and
soil carbon (both utilisation and sequestration). We will certainly be
looking closely at the sites you mentioned to see what co-operative
associations can be developed.