19/8/21, 00:00

Friday the 13th, 8:00 a.m. Closing the Carbon Gaps in Our Soils

Guillermo Peralta spoke about the opportunities to close the carbon gaps in soils and introduced the Carbon Gap Network led by Aapresid together with agencies from the industry.

Florencia Cappiello (Aapresid Press) 

Guillermo Peralta (CONICET) spoke about the opportunities to close carbon gaps in soils.  "The carbon (C) plays a key role in soils, as it is the main support of their productive  capacity: maintaining the structure, its venting capacity, infiltration and regulating the  content and cycle of nutrients." 

Small changes in soil C storage capacity—through appropriate management practices— have a great impact on the capture of the CO2 greenhouse gases, being one of the most  promising strategies in climate change mitigation due to its scalability. 

Carbon sequestration in soil depends on the balance of inputs and outputs. Inputs are  through integration of plant biomass, root exudates, microbial biomass, etc. Outputs are  caused by phenomena such as erosion, leaching and mainly by stubble decomposition  and mineralization of organic matter. 

Climatic, edaphic and management factors influence this balance and sequestration  capacity: areas with higher rainfall increase productivity and therefore greater C input; clay  soils protect C; and as for management, the greatest impact comes from roots and stubble. 

There is no linear relationship between C input and stock. After a period of time, which can  be up to 20-30 years, the C level reaches a stabilization point that depends on  management, soil, environment, etc. 

Three levels of soil C can be identified: the potential or biophysical—defined by soil  characteristics such as texture—, the achievable or environmental potential—defined by  radiation supply, temperature and water balance—and the current level—linked to  management, physical and nutritional status, tillage, rotation, etc. 

We believe that there are gaps between the different levels of C and that it is possible to  narrow them through various strategies. The gap between achievable and potential can be  narrowed through external inputs such as fertilizers, liquid manure, etc. The gap between  what is real and what is achievable can be closed with appropriate management  practices.

Practices such as fertilization, no-till farming techniques, intensive and diverse rotations  with service crops can imply accumulations of 200 kg C/ha, 400-500 kg C/year, even  higher with pastures. 

Finally, Peralta announced the creation of the Carbon Gap Network, a project led by  Aapresid, public agencies and universities. This network will have the following purposes:  quantifying these gaps in different regions of the country, identifying systems with greater  sequestration capacity as well as the impact of different practices on these gaps,  generating gap distribution maps and creating a network for the generation and exchange  of information. 

The project will have several stages: gathering information from producers on current  organic matter levels, linking this data with simulation models to provide forecasts,  calculating potential and achievable levels, and finally, identifying the most appropriate  strategies to close the gaps in each region. 

"The world demands traceability and carbon footprint, as well as monitoring, reporting and  verification (MRV) systems that will be transformed into valuable C credits. On this path,  the role of the producer is crucial. In this network that we are forming, the producer is not  only the protagonist in the generation of information, but also a facilitator to reduce the C  gaps," Peralta closed.