New Direction for Farming

In “Report of the Condition of Agricultural Land in South Australia” (Department of Water, Land, and Biodiversity Conservation, December 2004), the Executive Summary states …

“There are 10.2 million hectares of land used for farming in South Australia. This land has been cleared of its native vegetation and almost all of it has suffered some form of degradation as a result of farming systems that are inadequately aligned with sustainability requirements of its natural resources. Loss of productive capacity of agricultural soils results in adverse environmental, economic and social impacts, many of which are effectively irreversible.”

This same report states for agricultural land in South Australia:

  • “About 781,000 hectares...have a moderate to high inherent susceptibility to water erosion by virtue of soil type and land slope.”
  • “About 2.4 million hectares … have a high inherent susceptibility to wind erosion, due mainly to having sandy soils.”
  • “At least 1.9 million hectares ... is either already in a degraded state due to acidity, or is on the brink of damage due to acidification.”
  • “The area of land directly affected by water-table induced secondary salinity in the agricultural and remnant native vegetation areas of the state is estimated to be around 398,000 ha. This is predicted to increase to about 593,000 ha in the next 20-50 years, with most of the increase on the coastal plain of the Mid and Upper South East.” 
  • “Almost 1.7 million hectares...have soils with physical properties that make them inherently susceptible to soil surface structure breakdown.” 
  • “The majority of South Australian soils have very low natural phosphorus levels, and often have trace element deficiencies. Without very large inputs of key nutrients, agricultural productivity would be very low.” 
  • “There are about 2.48 million hectares ... that are moderately to severely affected by water repellence.” 
  • The rate of revegetation of native species for non-commercial purposes is about 4,000 ha annually. "It will take many decades of revegetation at this rate to have a significant impact on major NRM issues like dryland salinity, soil erosion or native habitat restoration.” 

These are alarming statistics, and recall that the figures quoted relate to a total agricultural area of 10.2 million hectares. The situation has not changed in the state since that report of 2004. There are numerous statements similar to these in the literature.

New direction needed

What does all this mean?

It means that South Australia needs a new direction, and urgently. It needs to be substantially more than an “adaptation” model. Adaptation to my mind means acceptance of the inevitable – and of course these inevitabilities have been clearly enunciated in the Draft Framework document – but there is one aspect that is absent, and it is as though it is beyond comprehension or indeed beyond the realms of economic capacity. I'm referring to very extensive landscape-scale change.

The real danger is that there are few if any plans in place for a new direction. We should not accept that declining rainfall will continue, because it may just be possible to have an effect (see discussion below) by taking action in restoring a natural balance.

The concern for the future is continual decline and further retreat of agricultural production and decline of the rural population. The effects will be continued urban sprawl of metropolitan Adelaide as people migrate to where jobs are available. The consequences of this scenario will be profound. The rural sector will fade to irrelevance.

The adaptation response (section 4.6) “increasing demand for agricultural crops as world population rises” will count for nought if soil fertility, rainfall, and different agricultural responses can not provide the output.

South Australia's soils are trending towards exhaustion, and the cropping and grazing systems risk more frequent episodes of failure. It will be insufficient, and inappropriate in terms of sustainability, to rely on genetics and biotechnology to maintain farm and rural productivity in the future.

So, what has all this got to do with adapting to a changing climate? Because it is all about SUSTAINABILITY.

When land clearance was in full swing in the period 1860-1880 and then from 1900, there was no consideration of the long-term effects on landscapes, soils, ecosystems, biodiversity. The prime motivation for the government of the day was to remain the number one grain producer in the land. As history reveals, other states soon caught up as the years rolled by.


For comparisons of cleared lands between 1986 and 2010, see the maps at Landscape Change & Sustainability

An unwelcome legacy

But the legacy of those years of land clearance are being felt today more than ever. At least 10.2 million hectares of land have been cleared, ecosystems wiped out, and extinction of species unknown. 

It is only in recent years that two species thought to have been extinct have been “rediscovered” - the spiny daisy and the pygmy bluetongue lizard, both in the Mid North region. How many other species are out there surviving in tiny enclaves? How many have been erased forever?

Mallee was once widespread across the state, generally in a band along the southern extents, but today there are just remnants, some tiny, many very isolated and disconnected. The mallee lands were seen as good cropping land by the pioneers, but what has been lost is affecting local and regional climate today.

If we are to accept what is contained in the report It's About People : Changing Perspectives On Dryness (“Drought Policy Review Expert Social Panel” - Report to the Minister for Agriculture, Fisheries and Forestry, Canberra, September 2008), then the underlying assertion is that at the very least a proportion of what was removed from the landscape in those many decades of land clearance must be replaced, if community health is to prevail.

If we are to accept the statement made earlier that “farming systems ... are inadequately aligned with sustainability requirements of its natural resources” then change must occur.

Of critical importance, if we accept the outcomes of the report Modelling impacts of vegetation cover change on regional climate (Land and Water Australia, July 2009) then there is only one option for South Australia. 

To illustrate my point, I quote from the study for this report, which concluded :

The study demonstrates the need for more integrated, long-term and adaptive policies and regional natural resource management strategies that restore the beneficial feedbacks between native vegetation cover and local-regional climate, to help ameliorate the impact of global warming. There is a critical need to reassess national climate change and natural resource management policies to include the interactions and feedbacks between the land surface and regional climate, particularly the role native vegetation plays in ameliorating climate extremes and the severity of droughts.

And in another two extracts :

In recent decades, the deforestation of the Australian landscape has been compounded by increased and sustained land use pressures arising from a steadily growing human population, rapid economic growth and rising global demand for Australian commodities, especially mineral and energy exports. There are also pressures on the extensive rangelands, with the sustainable management of rangeland landscapes continued to be outpaced by the need for growth, droughts, personal gain and invasive species. It is likely therefore that loss of ground cover due to drought and overgrazing will have a similar effect on energy fluxes and convective processes as broad-scale land clearing. A major uncertainty in attributing causes to changes in perennial land cover (trees and shrubs) in agricultural and rangeland landscapes results from the number of interacting factors involved (CO2, grazing management, frequency of pasture burning and wildfires, and severity of intermittent drought).

The risks of ignoring the role of land surface feedbacks in current and future droughts are potentially catastrophic for Australia’s environment, economy and communities. Climate changes due to increased anthropogenic greenhouse gases coupled with land surface feedbacks appears to be amplifying the natural climate variability and has the potential to tip Australia’s climate, especially in southeast Australia, into a new regime of more extensive, frequent and severe droughts. The combined effect of transient increases in greenhouse gases and pressures from land use/land cover change may already be contributing to more severe droughts for eastern and southern Australia, and is an ominous sign for the increased incidence and severity of projected future droughts.

For years I have been writing about the urgent need for landscape-scale change in South Australia. I have presented submissions to Northern & Yorke NRM Board (my regional board) on this subject, and I have presented similar responses to other research investigations. Unfortunately there does not seem to be the will to embark on landscape-scale change. These are opportunities lost. I see it everywhere I drive (and that is extensively) in rural South Australia. I witness decline of natural capital.

Conclusion All of this decline can be arrested, but it will take a new direction, a new form of agriculture and land use, to be introduced.

Here's what can be done about LANDSCAPE CHANGE.

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