August 7, 2013
Dust Storms And Wind Erosion Are Eating Away At Australian Soil
April Flowers for redOrbit.com - Your Universe Online
A new study from The Commonwealth Scientific and Industrial Research Organization (CSIRO) of Australia shows that although topsoil is rich in nutrients and carbon, it is increasingly being blown away by events such as the "Red Dawn" in Sydney in 2009.
The amount and location of soil carbon is changed when wind lifts carbon dust into the atmosphere. Some of the carbon falls back to the ground, some leaves Australia and some ends up in the ocean, according to the study.
Dr. Adrian Chappell, CSIRO research scientist, and an international team of wind erosion and dust emission experts calculated the extent of these carbon dust emissions. The results of their study were published in a recent issue of the journal Global Change Biology.
"Carbon stored in our soils helps sustain plant growth. Our modeling shows that millions of tons of dust and carbon are blowing away, and it is uncertain where all that ends up," Dr Chappell said.
"We need to understand the impact of this dust carbon cycle to develop more accurate national and global estimates of carbon balances and to be able to prepare for life in a changing climate. Australia's carbon accounts, and even global carbon accounts, have not yet taken wind or water erosion into consideration and when this happens it could have significant impacts on how we manage our landscapes. While soil organic carbon lost through dust is not a major contributor to Australia's total emissions, it is a major factor in our deteriorating soil health."
Carbon is essential for healthy soils in Australia, or anywhere. These soils underpin the nation's capability to feed 60 million people. Dr. Chappell says that understanding the movement of carbon through the landscape is a necessity if we are to improve the quality of our soils and support farmers and land managers to store carbon.
He also stresses that this is not merely an Australian issue. Other nations will need to understand the fate of their wind-blown carbon as countries like the US and China, both of which have larger dust emissions, will likely face similar challenges when including wind borne dust in their carbon accounting.
The frequency and intensity of dust storms is predicted to increase in Australia, which will increase the impact of wind erosion as well. Understanding this redistribution of carbon will improve land management practices, allowing for better protection of the soils.
The Red Dawn dust storm that passed over the eastern coast of Australia on September 23, 2009, cost the economy of New South Wales an estimated $267 million USD , mainly for household cleaning and associated activities. The red haze was caused by a sustained period of wind across NSW and southern Australia, areas that were heavily affected by a drought at the time. The rising sun hit that blanket of dust, causing the fiery red sky.