WEDNESDAY, JAN 25, 2023: NOTE TO FILE
Module 3-7
The potential of carbon sequestration and mitigation of climate change
This section has thus far elaborated on the importance of soils rich with organic carbon, or humus [humus aka organic matter], to support a greater biodiversity and life on earth in general. Yet, despite this knowledge, humanity still pursues industrial agricultural practices which destroys life in the soil and all supporting ecosystems, besides releasing huge amounts of GHGs into the atmosphere. Nevertheless, there is a growing awareness of these dangers, together with sustainable solutions to transform agriculture to more sustainable practices. In particular, the astounding ability of regenerative agricultural practices to restore humus rich [high organic matter] soils that can sequester carbon from the atmosphere [only for a time as all organic matter in soil is subject to microbial degradtion. As Wikipedia notes, "recent work suggests that complex soil organic molecules may be much less stable than previously thought: “the available evidence does not support the formation of large-molecular-size and persistent ‘humic substances’ in soils. Instead, soil organic matter is a continuum of progressively decomposing organic compounds.″After a hundred year there may be a few molecules left that are that old, so soil does not sequester long term (centuries to millennia)].
In April 2014, the Rodale Institute published [self-published, in in a journal of science] a white paper on Regenerative Organic Agriculture and Climate Change that outlines how agricultural techniques available today could sequester sufficient amounts of atmospheric carbon to slow down climate change and reduce greenhouse gas concentrations in the long term by fixing carbon in agricultural soil. Regenerative agricultural practices can help to build fertile soils [not farming soils helps more], to maintain and often increase agricultural yields [for humans], and to support ecological abundance by nurturing healthy ecosystem functioning. The report states:
“Simply put, recent data from farming systems and pasture trials around the globe show that we could sequester more than 100% of current annual CO2 emissions with a switch to widely available and inexpensive organic management practices, which we term regenerative organic agriculture. These practises work to maximize carbon fixation while minimizing the loss of carbon once returned to the soil, reversing the greenhouse effect”.
Rodale Institute (2014).
Robert Rodale coined the term ‘regenerative organic agriculture’ to indicate that these practices are more than simply ‘sustainable’, taking advantage of the natural tendencies of ecosystems to regenerate when disturbed. Regenerative organic agriculture is “a holistic systems approach to agriculture that encourages continual on-farm innovation for environmental, social, economic and spiritual wellbeing”. In general, “regenerative organic agriculture is marked by tendencies towards closed nutrient loops, greater diversity in the biological community, fewer annuals and more perennials, and greater reliance on internal rather than external resources”, (Rodale Institute, 2014). [Could the Rodale Institute make a claim that could be verified? Yes.]
The World Bank has released a detailed report on Carbon Sequestration in Agricultural Soils which reviews the different ‘abatement rates’ (measured in tonnes of carbon dioxide equivalent sequestered per hectare per year) of different land management practices and how effective they are in different regions of the world. The report highlights that “in addition to storing soil carbon, sustainable land management technologies can be beneficial to farmers because they can increase yields and reduce production cost”.
At this point, it is worth noting the typical composition of undisturbed soil in nature, which is approximately 46% grit, 25% water, 25% air and 4% humus (organic living matter [OM with organisms inhabiting it]). With convention-type agriculture that tills and compacts the soil, the air and water is squeezed out whilst the humus is destroyed through the application of chemical fertilizers, pesticides, herbicides, fungicides, etc., thereby resulting in a hard compacted and lifeless soil [that currently feeds, for a time, 8 billion humans to excess]. Limited till methods rip the soil thereby allowing air and water penetration for plant roots to take up essential minerals. In time, as this process is repeated with an appropriate regime of crop rotations and controlled mob grazing, the humus is restored back to its original undisturbed state.
The humus in the soil is effectively the glue which binds the grit, water and air. Therefore, as the humus levels increase, so does the ability of the soil to retain moisture and sequester carbon. Dr. Christine Jones (www.amazingcarbon.com) has documented this research, as reflected in Table 2.6, which shows how an increase in one percent humus (or Organic Carbon) effectively doubles the moisture retention and carbon sequestration of the soil.
Since conventional agriculture has rendered the average farm soil to less than 0.5%, there is an incredible potential to simply restore soils through Regenerative Agriculture so that moisture can be retained, plant vitality can be increased, but even better, carbon can be sequestrated.
['The half life value ranged from 139 days in the sandy soil and 187 days in the clay soil for poultry manure compost to 9989 days [27 years for biochar wood burned in absence of oxygen (i.e., pyrolysis)] for green waste biochar. Addition of clay materials to compost decreased the rate of decomposition, thereby increasing the stabilization of C. PubMed]. In anerobic conditions biochar can have a minimum 1000-year half-life, but turning forest into biochar is limited on a deforested planet.
Table 2.6: Quantifying the benefits of humus in the soil
The Regrarians have quoted PA Yeomans as saying that if all the arable land on earth manages to increase its humus content by just 1,6% in the top 30cm of soil, it will be sufficient to revert to 299 ppm of CO2 in the atmosphere from the current 413 ppm within a few years. Dr. Elaine Ingham has made similar estimates in the short video titled, “Soil Carbon Sequestration and the Soil Food Web”, which is encapsulated in the statement, “Climate Change poses an existential threat to humanity. Soil Carbon Sequestration is widely being recognized as a part of the solution to this problem”. Putting the soil carbon back into the soil also supports greater biodiversity and species regeneration.
[Dr. David Johnston, New Mexico State University Institute for Sustainable Agricultural Research (ISAR) in Las Cruces, NM, of Johnson-Su Bioreactor fame, making energy-blind claims to science illiterates based on results that cannot scale up.]
It can therefore be argued [by those who would rather believe than know] that farmers of the world have the potential to almost single-handedly sequester the earth’s entire CO2 emissions by reverting to an acceptable CO2 level that ought to curb runaway Climate Change. If sufficient moral emphasis is placed on all stakeholders - government, corporations and the private sector – to invest in the global carbon markets to buy back CO2 emissions, is this not then the investment game changer to drive Regenerative Agriculture?
Module 3, lesson 8
