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 email@example.com 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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