The role of plants in climate change mitigation

Australian businesses will need to pay an estimated $65 billion to purchase international Carbon Credits. This cost will inevitably be passed on to consumers in increased prices for goods and services.

Scientists know that actively growing vegetation will absorb CO2, nitrogen and water vapour from the atmosphere and release O2 as a by-product. Using plants to manage water could turn this $65 billion deficit into $180 billion in credits to our economy and our environment over 3 years. This information can be demonstrated but not modelled on a computer.

Atmospheric nutrients are the start of the Carbon cycle that in turn produces the terrestrial food chain. This productivity nourishes us, sustains the landscape and indirectly buffers the economy against the effects of climate extremes. It keeps the environmental show on the road – prevents erosion, purifies the water and modifies the temperature.

If one cubic metre of water drains to the sea, the land is subjected to 750 kW of unmanaged heat. This kind of heat is called “sensible heat” because it can be felt. When the sunlight hits a bare surface (a roadway, concrete pavement or bare ground) it warm that surface which then radiates the heat upwards. Heat managed by water is called latent heat – condensation keeps cold areas warm and transpiration keep warm areas cool. Plants photosynthesise and transpire in a process called primary production.

Agricultural research during the second half of the last century encouraged the use of chemicals to stimulate food production. However, these chemicals resulted in our crops and pastures releasing more CO2 and nitrogen (both greenhouse gases) than they absorbed or sequestered.

The growth of our cities has also had a critical climatic impact – the heat island or hot plate effect of hard surfaces radiates enough heat to power a tropical cyclone.

A flight from Perth to Sydney will reveal a significant portion of Australia’s 20.6 million hectares under crop and 53% of this is located within the Murray Darling Basin. Right now, it is green or in flower. In another 3 weeks the harvest will begin and this area will be stripped or mown, leaving the area inactive or dead. Instead of absorbing heat from the sun, this huge area will be reflecting it. After about 4 - 6 weeks, violent storms will hit Sydney, Melbourne and most of the East Coast.

There are ways to prevent this climatic mayhem. An understory of summer active grasses or legumes should be used within the cropping system (pasture cropping) or the crop area can be interspersed with productive trees, grasses and shrubs along the contour in a pattern known as alley farming – nut, fruit, fodder and timber trees, vegetables, garlic and bamboo would all do the job. These strategies are known as “positive feedback loops” and explain NSF most accurately. In common parlance a feedback loops are described as follows:
“..feeding back part of the output so as to increase the input is positive feedback (regeneration); feeding back part of the output in such a way as to partially oppose the input is negative feedback (degeneration)1.” The more positive feedback loops that can be connected in a landscape process, the greater the accumulation of ecological capital. Hence NSF is dedicated to regenerative processes and much of our industrial agriculture is based upon degenerative practices.
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Unless and until there is a deeper understanding among governments, farmers, bureaucrats and industry that water, sunlight, plants and mulching/composting create stable, productive environments we will continue to be led up the garden path to a hotter and more violent climate. No ETS nor Carbon Tax will rectify the situation. Fixing the climate (and the Carbon cycle) can be achieved by intelligent intervention in landscape processes not by financial engineering. ​