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land for agriculture, conventional tillage
practices, and overgrazing (Lal, 2004;
Montgomery, 2007). Conventional land
management practices cause physical distur-
bance of soils and have historically promoted
enhanced agricultural yields, to the detri-
ment of SOC content, topsoil thickness, and
overall soil health and structural stability
(Phillips et al., 1980; Reganold et al., 1987;
Amundson et al., 2015). The systematic
exploitation and modification of undisturbed
soils has led to the resulting agricultural soils
being dubbed “domesticated,” lacking hall-
mark resilience of their wild predecessors
(Amundson et al., 2015). Soil domestication
for agriculture also presents broader, associ-
ated ecosystem issues, such as diminished
biodiversity from engineered crop commu-
nity monocultures, introduction of chemical
pesticides to hydro- and pedospheres, and
the delivery of vast quantities of esp. nitro-
gen and phosphorus fertilizers to coastal
margins. Conservation tillage and organic
farming have been proposed as alternative
approaches that enhance soil health and to
limit unsustainable soil “mining” and asso-
ciated SOC overspending (Montgomery,
2007). Estimates maintain that tillage man-
agement, when paired with cropping sys-
tems, can sequester 0.03–0.11 Pg C yr
–1
(Follett, 2001). Despite these promising
Figure 1. Soil organic carbon (SOC) is a dynamic and complex admixture. Here, three contrasting eco- advances, human civilization and associated
systems reveal differing SOC richness and dynamics: (A) agricultural, (B) grassland/shrubland, and (C) changes in land use and land cover led to the
forested. Conventional agriculture (A) often leads to lower carbon stocks, and overall, less carbon loss of 120 Pg C in the upper ~2 m of soils
input to the soil carbon pool. Grasslands (B) can harbor plants with deeper and more extensive root
systems, medium to high amounts of SOC stock, and greater carbon inputs to the SOC pool. Forests since humans adopted agriculture, with the
(C) can have the deepest rooting system, a high amount of soil C stock, greatest density of mineral- fastest rate of loss occurring in the past 200
associated C, and high rate of input of C to soils. Overall, organo-mineral association(s) and SOC pool
is a function of the “balance” of C inputs and outputs in the soil organic carbon “bank account.” years (Sanderman et al., 2018).
Land Use/Land-Use Change (LULUC)
withdrawal of some of the balance from the In this framework, we identify strategies for practices such as conventional agriculture,
soil carbon checking account) is a critical soil C sequestration and ways to prevent deforestation, and wetland conversion con-
ecosystem process because decay of organic “overspending” in an uncertain future tribute 10%–14% of overall anthropogenic
residue provides essential nutrients for marked by changing climate and increased greenhouse gas emissions (Paustian et al.,
plants and microbes in soil (Janzen, 2006). demands to ensure food and nutritional 2016). The SOC pools impacted by LULUC
For this reason, we cannot expect zero with- security of the growing human population. have the potential to release massive amounts
drawals from the soil carbon bank and must of C to the atmosphere, making the preserva-
figure out how we can continue to “invest” CARBON LOSSES DUE TO tion of these environments critical to protect
in soil C to maximize its input and retention CONVENTIONAL SOIL USE soil C from loss both by reducing future
in the soil, thus preventing fast release of C AND DEGRADATION releases of C from soil to the atmosphere
as greenhouse gasses to the atmosphere. An increasing human population and (avoided fluxes) and promoting drawdown of
Maintenance of soil health through “smart” onset of the industrial age led to an increased C that is already in the atmosphere (seques-
management practices has been proven to demand for food, energy, and water re- tration of atmospheric CO ). Deforestation
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simultaneously achieve SOC sequestration sources, and overall intensification of the was historically practiced to clear land for
and provision of clean air, water, and a agricultural sector. With intensive agricul- agriculture, but also continues to occur due
functional habitat (Billings et al., 2021; tural practices came large-scale degradation to urban development, logging, and an
Kopittke et al., 2022). Here, we explore pre- of the global soil resource that included increase in wildfire frequency and inten-
vailing issues with conventional soil man- increased rates of soil erosion (i.e., loss from sity. These activities can destabilize SOC,
agement, vulnerability of SOC to loss in a working lands) that outpaced new soil releasing slow-cycling C stored even in
changing world, and strategies to alleviate production by 1–2 order(s) of magnitude, deeper soil layers (Drake et al., 2019). This
cli mate-change impacts on soil resources. largely resulting from deforestation to clear also lowers ecosystem functions that SOC

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