Farms as Environmental Solution Providers

Farms as Environmental Solution Providers

Remark: The references mentioned in square brackets [  ] relate to the references used in the scientific report of dr. Arnold on the Biochar Calculator. You will find these references under References. The text is an excerpt of the scientific report.

Although many farmers are willing, motivated and committed – not only in theory but in practice – to contribute to environmental and climate protection and to animal welfare as well, perception of significant parts of the public, triggered by simplifying headlines, seems to be that farmers in many cases are causing more harm than good [ 18 ]. This is evidenced, for example, in the latest WWF report “Living Planet 2020” [ 16 ]. Here, for example, the public image of agriculture is considerably burdened by the one-sided allocation of a large part of the responsibility for global species loss and biodiversity [ 17 ].

On one hand, 10 percent of total greenhouse gas emissions in the U.S. or 23 percent globally don’t seem to be the major driving force of climate change. On the other hand, the target to reach a net-zero status of greenhouse gas emissions by mid of the century (Paris Accord of 2015) cannot be reached without including the agricultural sector, and here the emission causes (natural bio- and biogeochemical conversion processes) seem to be among the hardest to be tackled by technological means.

In contrast to this, soil could help to implement the required carbon-sinks (carbon dioxide removal, CDR, see [ 7 ]) which are necessary to reach CO₂,eq-net-zero conditions in spite of remaining greenhouse gas emissions where decarbonization fails or is impossible. Soil with an organic carbon content of more than 3 trillion Mt carbon in its upper layer of 2 m (nearly 4 times as much as the atmosphere) is already the major global deposit of carbon [ 22 ]. The global CO₂,eq-sink effect of soil amounts to about 3 billion Mt carbon [ 22 ] or 11 billion Mt CO₂,eq (eleven gigatons) per year which is equivalent to roughly one quarter of the global anthropogenic greenhouse gas emissions of today. The estimates of the soil potential as additional carbon sink range between 0.8 and 8 gigatons carbon per year [ 22 ] with a practically achievable magnitude of about 2 gigatons carbon per year or 7.4 gigatons CO₂,eq per year1 [22]. A more conservative meta-study of recent related publications estimates the global potential of soil carbon sequestration to be above at least 3 gigatons CO₂,eq per year [ 23 ]. However, to leverage relevant parts of this potential to compensate between 7% and 17% (estimates mentioned above) of the actual global anthropogenic greenhouse gas emissions, fast action is required, since “…the potential for some response options, such as increasing soil organic carbon, decreases as climate change intensifies, as soils have reduced capacity to act as sinks for carbon sequestration at higher temperatures.” [ 6 ].

In contrast to this, soil could help to implement the required carbon-sinks (carbon dioxide removal, CDR, see [ 7 ]) which are necessary to reach CO₂,eq-net-zero conditions in spite of remaining greenhouse gas emissions where decarbonization fails or is impossible. Soil with

an organic carbon content of more than 3 trillion Mt carbon in its upper layer of 2 m (nearly 4 times as much as the atmosphere) is already the major global deposit of carbon [ 22 ]. The global CO₂,eq-sink effect of soil amounts to about 3 billion Mt carbon [ 22 ] or 11 billion Mt CO₂,eq (eleven gigatons) per year, which is equivalent to roughly one quarter of the global anthropogenic greenhouse gas emissions of today. The estimates of the soil potential as additional carbon sink range between 0.8 and 8 gigatons carbon per year [ 22 ] with a practically achievable magnitude of about 2 gigatons carbon per year or 7.4 gigatons CO₂,eq per year [ 22 ]2. A more conservative meta-study of recent related publications estimates the global potential of soil carbon sequestration to be above at least 3 gigatons CO₂,eq per year [ 23 ]. However, to leverage relevant parts of this potential to compensate between 7% and 17% (estimates mentioned above) of the actual global anthropogenic greenhouse gas emissions, fast action is required, since “…the potential for some response options, such as increasing soil organic carbon, decreases as climate change intensifies, as soils have reduced capacity to act as sinks for carbon sequestration at higher temperatures.” [ 6 ].

Who else but those working with soil professionally, i.e., farmers, could be the ones who practically and soon put carbon back where it belongs? Hence, much action must take place until 2030 and at least some action is about to be put in place. The State of California, for instance, passed California’s Global Warming Solutions Act,

Assembly Bill 32, charging the California Air Resources Board (CARB) with reducing statewide GHG emissions to 1990 emission levels by 2030. Senate Bill (SB) 32 required further GHG emissions reductions of 40 percent below 1990 emission levels by 2030 [ 24 ]. With this background, California launched the short-lived climate pollutant reduction strategy (SB 1383) with the objective of decreasing CH4 emissions from livestock by 40% by 2030 from 2013 levels [ 21 ]. Meeting these targets would mean either to reduce the livestock numbers accordingly or to implement innovative methods of reducing enteric CH4-emissions especially of cattle e.g., by means of feed additives [ 21 ].

Compared with these efforts to reduce greenhouse gas emissions in California, the activities to foster the increase of soil organic carbon so as to build up an effective carbon sink are in an earlier stage. Based upon the “Healthy Soils Initiative” [ 33 ], which was recently supported by Governor Newsom’s order (executive order N-82-20 of Oct. 7, 2020, among other elements order to CDFA: “Enhance soil health and biodiversity through the Healthy Soils Initiative” [ 25 ]) a number of pilot projects are carried out in Resource Conservation Districts and NRCS California Conservation Field Trial Sites. The goal of these projects is to assess the impacts and benefits of “Carbon Farming” or “Agroecology” in soil management [ 26 ][ 27 ]. In these studies, not only the climate relevant impacts of increasing the soil organic carbon content are observed but additional benefits such as improved water retention and the reduction of industrial fertilizer demands as well. The goal of these and other initiatives towards sustainable agriculture is to achieve a balance between residual greenhouse gas emissions and the binding or immobilization of atmospheric greenhouse gases (carbon sinks, carbon storage in the soil) in the future, thus achieving a CO₂-neutral agricultural production.

However, the goals of these remarkable initiatives won’t be reached without acceptance and active participation of the farmers. Hence, conditions need to be established and instruments are to be provided that help farmers not only to survive economically but to draw significant benefits in terms of improved economic efficiency and net earnings from the necessary changes. In short words: Climate and environmental protection has to pay off for the farmer to be implemented successfully and in time.

Of course, appropriate legal framework conditions are required to resolve the conflicts of interest between agriculture, climate, environmental and animal protection as well as consumer interests. In addition, however, application oriented agronomic tools are necessary to support the decision makers, i.e., the farmers, in analyzing and evaluating the expectable economic impacts of changed cattle feeding, manure and slurry handling and soil treatment methods for their local and highly individual farm conditions.