Carlos Eduardo Pellegrino Cerri, Maurício Roberto Cherubin, João Marcos Villela, Jorge Luiz Locatelli, Martha Lustosa Carvalho, Federico Villarreal, Francisco Fujita de Castro Mello, Muhammad Akbar Ibrahim, Rattan Lal
Abstract
Soil represents Earth’s largest terrestrial reservoir of carbon (C) and is an important
sink of C from the atmosphere. However, the potential of adopting best management
practices (BMPs) to increase soil C sequestration and offset greenhouse gas (GHG)
emissions in agroecosystems remains unclear. Synthesizing available information
on soil C sink capacity is important for identifying priority areas and systems to
be monitored, an essential step to properly estimate large-scale C sequestration
potential. This study brings an overview of thousands of research articles conducted
in the Americas and presents the current state-of-the-art on soil C research.
Additionally, it estimates the large-scale BMPs adoption impact over soil C dynamics
in the region. Results indicated that soil C-related terms are widely cited in the
literature. Despite that, from a total of ~13 thousand research articles recovered
in the systematic literature review, only 9.2% evaluated soil C (at any depth), and
only 4.6% measured soil C for the 0–30 cm soil layer, mostly conducted in North
and South America regions. Literature review showed a low occurrence of terms
related to BMPs (e.g., cover cropping), suggesting a research gap on the subject.
Estimates revealed that upscaling of BMPs over 30% of agricultural land area (334
Mha) of the Americas can lead to soil C sequestration of 13.1 (±7.1) Pg CO2eq over
20 years, offsetting ~39% of agricultural GHG emissions over the same period.
Results suggest that efforts should be made to monitor the impact of cropping
system on soil C dynamics on the continents, especially in regions where data
availability is low (e.g., Central, Caribbean, and Andean regions). Estimating the
available degraded area for the continent and the soil C sequestration rates under
BMPs adoption for Central, Andean, and Caribbean regions were major shortcomings
encountered in our analysis. Thus, it is expected that some degree of uncertainty
may be associated with the obtained results. Despite these limitations, upscaling
of BMPs across the Americas suggests having great potential for C removal from
the atmosphere and represents a global positive impact in terms of climate change
mitigation and adaptation.
sink of C from the atmosphere. However, the potential of adopting best management
practices (BMPs) to increase soil C sequestration and offset greenhouse gas (GHG)
emissions in agroecosystems remains unclear. Synthesizing available information
on soil C sink capacity is important for identifying priority areas and systems to
be monitored, an essential step to properly estimate large-scale C sequestration
potential. This study brings an overview of thousands of research articles conducted
in the Americas and presents the current state-of-the-art on soil C research.
Additionally, it estimates the large-scale BMPs adoption impact over soil C dynamics
in the region. Results indicated that soil C-related terms are widely cited in the
literature. Despite that, from a total of ~13 thousand research articles recovered
in the systematic literature review, only 9.2% evaluated soil C (at any depth), and
only 4.6% measured soil C for the 0–30 cm soil layer, mostly conducted in North
and South America regions. Literature review showed a low occurrence of terms
related to BMPs (e.g., cover cropping), suggesting a research gap on the subject.
Estimates revealed that upscaling of BMPs over 30% of agricultural land area (334
Mha) of the Americas can lead to soil C sequestration of 13.1 (±7.1) Pg CO2eq over
20 years, offsetting ~39% of agricultural GHG emissions over the same period.
Results suggest that efforts should be made to monitor the impact of cropping
system on soil C dynamics on the continents, especially in regions where data
availability is low (e.g., Central, Caribbean, and Andean regions). Estimating the
available degraded area for the continent and the soil C sequestration rates under
BMPs adoption for Central, Andean, and Caribbean regions were major shortcomings
encountered in our analysis. Thus, it is expected that some degree of uncertainty
may be associated with the obtained results. Despite these limitations, upscaling
of BMPs across the Americas suggests having great potential for C removal from
the atmosphere and represents a global positive impact in terms of climate change
mitigation and adaptation.
