Regenerate Earth: The practical drawdown of 20 billion tonnes of carbon back into soils annually, to rehydrate bio-systems and safely cool climates

Authors

By Walter Jehne, Healthy Soils Australia

Publication

Written for Breakthrough Strategies’ Sequestering Carbon in Soil Addressing the Climate Threat Conference in Paris | May 2017.

Summary

There is only one process via which we can secure our safe climate and future. This is pedogenesis: the microbial bio-conversion of plant exudates and detritus into stable soil carbon. Our future is governed by how well we manage to regenerate the Earth’s soil carbon sponge. While plant photosynthesis is critical to fix solar energy into plant bio-mass, it is what happens next to that biomass that matters. Does it rapidly oxidize back to CO2 by burning or does it get partly bio-converted by fungi into stable soil carbon? There are no other options.

Pedogenesis, the evolution of soils and bio-systems, their hydrology, our stable climate, resiliency in the face of flooding and drought, and regional and global cooling all depend on this simple balance between how much of the carbon that is fixed by plants is burnt or bio-sequestered. We live in the balance between fire and fungi. As humans we can, and have, only influenced the Earth’s geo-chemical processes and climate via our capacity to alter the balance between these two processes that govern the carbon dynamics of the planet. Are we oxidizing or bio-sequestering its carbon, are we managing our food production, environment, and climate via fire or fungi?

While human civilizations can prosper, briefly, by oxidizing the carbon and natural capital of their bio-systems via the clearing and burning of vegetation, the cultivation and degradation of soils, and excessive use of synthetic fertilizers, biocides, irrigation and bare fallowing to meet their food and bio-resource needs, such civilizations are deigned to—and will—collapse. Alternatively, if we respect pedogenesis and how natural bio-systems regenerate, we can turn the dead mineral detritus and deserts from such collapses back into productive soils and bio-systems on every continent, as nature did 420 million years ago and repeatedly still does. In doing so we can enhance the hydrological and nutrient cycles so they can sustain the water, food and ecological services we all depend on for life.

Our management of these processes of ‘fire or fungi’ now largely governs to what extent land management practices oxidize the carbon and thus destroy the living structure and productivity of our soils or alternatively restores them by allowing plants to draw down carbon from the air and bio-sequester it back into soils via fungi. We can choose to what extent our land is turned into either desert or healthy productive bio-systems, by fire or fungi.

The abnormal rise in atmospheric CO2 levels over the past 250 years should be seen as a clear symptom that we have grossly impaired the Earth’s natural carbon dynamics via its excessive oxidation by our extended land clearing, burning, and tillage over millennia. The accelerated rise in CO2 levels over the past 60 years is linked to our recent accelerated emissions from the burning of fossil fuels and our industrial agriculture. Slowing down or even reversing these symptoms will not rectify their underlying cause: our gross impairment of the Earth’s natural carbon oxidation-to-drawdown balance. We can only rectify this by regenerating the carbon drawdown capacity of the Earth’s residual bio-systems as outlined in this proposal.

However, after 50 years of denial and delay, our task may not be that easy or simple. The evidence is that our degradation of our bio-systems and their hydrological dynamics has already dangerously exceeded planetary climate buffers and thresholds. This is accelerating a range of positive climatic feedback processes, resulting in intensifying dangerous hydrological extremes not able to be moderated by the oceans’ former vast natural buffering and lag effects. These hydrological extremes now pose major risks to most of the Earth’s natural bio-systems, stable climate and our future. All the evidence points to the fact they are intensifying, and will continue to do so.

As such we now have left ourselves no option but to use nature’s own strategies to safely and naturally cool climates to try to buffer and limit these dangerous hydrological extremes. Fortunately, we should be able to still do this but only a nature does: by drawing down carbon from the air back into our soils, not just to reduce the CO2 symptoms, but to regenerate the Earth’s soil carbon sponge, its in-soil water reservoirs and synergistic processes to restore its former bio-systems, natural former drawdown capacity and thus the natural hydrological cooling processes.These hydrological processes still govern 95% of the heat dynamics of the blue planet. Restoring the processes we have impaired is now our only means to safely cool the climate.

This outcome can now only be achieved via global grassroots community action to draw down carbon to regenerate the Earth’s soil carbon sponge, its hydrology and bio-systems. Global and national policies must provide these grassroots communities with the certainty and incentives they need to be able to invest in such mass regenerative action. The COP21 zero-net emission and then negative net emission targets, the introduction of a commercial globally verified carbon accounting and trading system, and a valid carbon price are all important positive components and steps in this critical global last chance response.

While we can and must regenerate Earth via these processes, we are running out of time. By embracing and empowering practical grassroots action to implement blueprints such as this to draw down the 20 btC/an we can now secure our safe climate and future. More than ever our wellbeing, climate, and future lies in our soils, and in your hands.