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Soil Carbon Sequestration in Victoria by lindayy

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Soil Carbon Sequestration in Victoria

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									                                    Inquiry into soil carbon sequestration in Victoria
                                                                  Submission no. 30

Environment and Natural Resources Committee of the Parliament of Victoria
inquiry into:

Soil Carbon Sequestration in Victoria
Submission from Patrick Francis

31 Ryder St, Niddrie Vic 3042

64 Moffats Lane Romsey Vic

03 9379 2607, 0418 351 567

francis@ozonline.com.au

Patrick Francis is an agricultural scientist (Melbourne University 1972) who has a
small trial farm, “Moffitts”, at Romsey Victoria on which he compares different
farming systems and implements environmental monitoring. These have come to
his attention over 30 years as editor of Australian Farm Journal (and FARM
Magazine) and 14 years as editor of Australian LANDCARE magazine.

“Moffitts” is regularly visited by landcare farming groups investigating holistic
management in a grazing and forestry enterprise, it has been a case study
example for an environment management systems book, and in 2009 for whole
farm carbon calculation booklet. “Moffitts” farm is a net carbon sink.

Patrick has visited many of Australia’s leading livestock and cropping farmers
and written about developments in broadacre cropping and grazing systems and
research for 30 years. This provides him with a unique insight into developments
associated with soil health and soil carbon sequestration associated with
conventional farming, biological farming and organic farming. He also writes
about overseas farming systems and research with respect to soil health and soil
carbon sequestration.

Patrick contends the critical issue that must be addressed about soil carbon is
the failure to monitor impacts of farming methods on this characteristic. Farmers
will not appreciate soil carbon dynamics and its sequestration benefits until they
begin to regularly monitor it just as they do soil nutrients, pH and livestock and
crop productivity. Only then will they be able to associate management systems
with their impact on soil carbon and other environmental indicators. Most farmers
do not monitor soil carbon levels and have no idea in what direction they are
heading.

a) explore possible benefits to the agricultural industry;
On any farm the trend over time in the percentage of carbon held is most
important indicator of the health of the farm ecosystem. If soil carbon content is
gradually improving it indicates that a range of ecosystem services are being
provided including:

   •   improved soil water holding capacity leading to less surface runoff and
       more sub service water infiltration and lateral flow to springs and wetland.
       It ensures better pasture and crop growth throughout the growing season
       and with summer active introduced or native perennial plant species year
       round growth
   •   an improved soil food web, so that nutrients in soil and organic matter are
       being recycled and made available to plants – less fertiliser is required
       provided soil fertility is not run down. Proliferation of mycorrhizae fungi
       which are associated with increasing soil humus a stable soil carbon
       component.
   •   crop and pasture productivity will be improving,
   •   there is less requirement for weed control herbicides as perennial plants
       are more competitive or in crops stubbles are more dense.
   •   the ecosystem is resilient to below average rainfall years, ie kg of grain per
       mm of rainfall is higher, as is dry sheep equivalents per 100 mm of rainfall.

On the other hand if soil carbon content is declining over time then a degrading
process is happening across the farm ecosystem. Productivity will be declining
and resilience in the face of below average rainfall will be reduced.

The key issue is that landowners and managers need to monitor soil carbon
content over the long term if they are to be recognised for credible farm
environmental improvement.

Victoria leads the way for farm environmental monitoring in Australia with the
DPI/VFF Environmental Best Practice Management (EBMP) program which
includes soil carbon monitoring amongst other indicators. Unfortunately EBMP
has not been taken seriously by the agricultural industry except amongst wine
growers, one group of Gippsland beef and sheep producers and in NSW cotton
growers.

It is interesting that the lack of monitoring by farmers of key environmental
indicators of their business to provide evidence of sustainable practice is likely to
have contributed to the Queensland Government introducing the Great Barrier
Reef Protection Amendment Act 2009. Under the Act farmers will have to
maintain records of fertiliser and herbicide use and prepare environmental risk
management plans.

The EBMP program was conceived in Ontario Canada in the 1990’s to give
farmers an opportunity to voluntarily conduct their own monitoring of key
environmental indicators to ensure adverse outcomes did not occur (eg water
contamination with pesticide) and avoid the introduction of legislation. EBMP is
highly successful in Canada with the program now adopted in all states and with
over 30,000 farmers involved.

(b) explore possible environmental benefits;

   •   river and stream water quality will be improving – less sediment, less
       nutrient runoff
   •   the soil food web will improve, this leads to increased biodiversity across
       the farm
   •   farms can become net CO2 sinks – especially the most degraded farms.
       Those that have lost more than 50% of soil carbon will have enormous
       potential to make the biggest improvement with improved crop and
       pasture agronomy and grazing management. These effects are
       demonstrated in the two figures: ‘Changes in land use’ and ‘Law of
       diminishing returns’. Source Kim Ritman ABARE Outlook March 2010
The following two tables demonstrate that soil carbon can be increased or
maintained by changing land management and practices PROVIDING soil fertility
is present.

  Table 1: Land use change from cropping to pasture leads to increase in soil
 carbon, and plantation (agro forestry/afforestation) may accelerate soil carbon
     sequestration to that under native vegetation (tonnes carbon per ha)
                                        Pasture +            Native
      Depth      Crop Pasture
                                        plantation         vegetation
       0-
                   40      70              83                  85
       30cm1
       0-
                   28      46                                  47
       20cm2
       0-
                   39    61 (45)                               83
       20cm3
         0-
                    43      56                                 58
         20cm4
1
  Nicole Mathers, unpublished data; 2Donald Ridge, 3Big Jacks Creek, 4Warrah
Ridge from Young et al. (2005). Source Ram Dalal GRDC Update Goondiwindi
March 2010
Table 2: Changes in soil organic carbon and Olsen P on “Moffitts” Romsey
Victoria plus comparison to adjacent unfarmed roadside.

Year /Paddock               Organic        Organic Total P ppm Olsen P
                            Matter %      Carbon %              ppm
2002 road                       9.3           4.6           654          17.4
2003 trial                      9.2           4.6           652          24.8
2005 top                       10.1           5.1           678          27.4
2006 dam                        7.4           3.7           351          21.5
2007 road                       8.6           4.3           453          22.2
2008 corner                     6.5           3.3           369          20.2

2009 Un-farmed                  5.1           2.6           232          14.5
Roadside




(c) consider methodologies for measurement of the effects of carbon
sequestration, including any potential issues associated with the
measurement of benefits;

We should be thinking about trends, soil carbon changes will be slow.
Measurement will not be needed every year. Year to year variation will exist but if
management is consistent eg No-till cropping with legumes plus manure plus
pasture leys, OR pasture cropping etc gradual increases will occur.

(d) identify the costs;



Soil carbon sequestration does not have a direct cost as it is occurs as a result of
change to the farming system. It should also be remembered that in systems
where soil carbon in improving, there is less fossil fuel energy used on the farm in
terms of diesel and fertiliser and therefore reduced greenhouse gas emissions
from this source. It is important to start monitoring CO2 emissions and carbon
sequestration in terms of whole farm balances.

Farmers have a range of ways to sequester carbon and reduce emissions, a
combination of these (including tree and fodder shrub planting) will be important
to achieve net sequestration across the entire farm in the majority of years. Ability
to sequester carbon in soil is highly dependent on soil type. For instance farmers
with sandy soil will put greater emphasis on tree corridors and fodder shrubs than
soil to achieve a net carbon balance or be a net carbon sink.

If there is a cost associated with soil carbon it would be in relation to undertaking
the analysis – taking cores and laboratory tests. Farmers should have their own
corers for 10 cm depth sampling. Sampling to 30 cm generally requires a
mechanical corer. Soil carbon analysis in the standard 10 cm cores is provided
alongside other nutrients at no additional cost to the farmer. Some skill is
required for correct soil sampling technique.




Patrick has prepared a PowerPoint presentation to demonstrate issues included
in this submission.

If the committee has time Patrick would also like to host a walk on his farm at
Romsey so members can see for themselves the sorts of initiatives he believes
are important for soil carbon sequestration and to achieve a whole farm net
carbon sink.

								
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