Farmers can save the planet before they destroy it, Australian climate scientist says

In a room full of regenerative agriculture faithfuls, Australian climate scientist and microbiologist Walter Jehne started the conversation.

Will farmers save the planet before they destroy it?

How the future plays out depends on how well the industry understands, respects and regenerates soils, he said.

Healthy biosystems across the world’s farmland provide stable hydrology, weather, economy and communities, he said during the annual Fuller Field School in Emporia last month. But the current picture of feeding a swelling population with limited resources isn’t rosy.

Jehne noted the growing extremes in global weather patterns, such as droughts, floods and wildfires. Moreover, he said, farmers have borrowed money on the concept to produce as much as they can from the land they have.

“It is really the unpredictability of growing a crop and the gamble of “will I have the season as expected to let me grow that crop, harvest that crop and avoid the diseases on that crop,” said Jehne, who is also the director of Healthy Soils Australia.

“As the climate changes and extremes intensify, that gamble is getting harder and harder to win. It’s like Russian roulette with four chambers loaded.”

Soil carbon sponge

Industrial agriculture—particularly since World War II—has been mining or oxidizing carbon, Jehne said, estimating farmers have mined over 50 percent of the organic matter from the soil.

“As we lose our soil structure, we also lose our water holding capacity,” he said. Jehne spoke about the dividends and commercial benefits farmers can receive from implementing practices to boost soil health.

“Basically every gram of carbon you put in the soil is 8 grams of extra water,” he said. “Every gram of carbon you put in the soil massively increases the nutrition availability, and you don’t need those fertilizer inputs. Every gram of carbon you put in the soil massively increases the microbial ecology—you got another 10 billion workers working for you, driving your productivity.”

Farmers and others can reverse the trend by restoring what he calls the soil carbon sponge. This underground infrastructure is water absorbing, enhances access to essential nutrients and supports a diverse range of microbial processes, Jehne said.

“Healthy soils rejuvenate the soil carbon sponge,” he said. “A healthy soil will have 10 times the fungi, bacteria, protozoa, nematodes, in that soil.”

Rejuvenating the sponge is done by taking planet-warming carbon dioxide out of the atmosphere and burying it back into the soil, he said.

He said to address the cause of the CO2 increase, the industry must rebalance the earth’s emissions and its capacity to drawdown carbon. The drawdown of carbon back into the Earth’s soil carbon sponge can regenerate soils and restore the vitality of the human and natural communities that rely on it.

Reducing CO2 emissions only addresses a symptom of global warming, Jehne said.

“Sure, it is fair enough to clean up the symptom—mop up the blood off the floor—but what is much more important is rebuilding the health of that organism, stopping the bleeding and that is about rejuvenating healthy soils and rebuilding the earth’s soil carbon sponge.”

Grassroots

That is the goal of his Healthy Soils Australia, which, through its network of farmers, scientists and others, promotes the regeneration of soil carbon, health and viability. Among the efforts they tout is holistic grazing, including cell grazing. Also, implementing cover crops into the cropping system helps build back organic matter and microorganisms while controlling weeds and decreasing input costs like fertilizer and crop protection products.

The organization’s goal is to regenerate and rehydrate 300 million hectares across northern and inland Australia.

Jehne noted that potentially, through the grassroots action by farmers, the drawdown of carbon could biosequester some 20 billion tons of carbon annually back into the world’s soils. That would more than offset the deficit of today’s net annual emissions.

According to the United Nations, 12 million hectares of arable land, enough to grow 20 tons of grain, are lost to drought and desertification each year.

“Yes, there has been erosion, soil degradation,” Jehne said. “But there is a fight from the grassroots community all over the world. “We are winning the game,” he said. “But we have further to go.”

Amy Bickel can be reached at 620-860-9433 or [email protected].