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Potential Co‐benefits and trade‐offs between improved soil management, climate change mitigation and agri‐food productivity

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Abstract

Abstract Maximising resource‐use efficiency, productivity and environmental sustainability are all fundamental requirements to raise global food production by ~70 per cent in order to feed a world population of ~9.7 billion people by 2050. Perhaps the most vital resource within our capacity to achieve this goal is our soil. Broadly, the fundamental question concerns whether or not satisfying this production demand will accelerate soil degradation, climate change, and the loss of soil carbon stocks. This paper builds upon the outputs of the UK Charity ‘Food & Farming Futures’ (chaired by Lord Curry of Kirkharle) virtual workshop held on 23 March 2021, entitled ‘Capturing the Potential of Soil’. The event focussed on the link between soil health, primarily soil organic carbon (SOC), and agricultural productivity. Supported with commentaries by Professor Pete Smith (University of Aberdeen and Science Director of the Scottish Climate Change Centre of Expertise) and Professor Steve McGrath (Head of Sustainable Agricultural Sciences at Rothamsted Research), specific focus will be given to the research challenges within the UK’s ability to improve soil health and functionality, the implementation priorities that must be held in order to improve soil management by 2050 and what the potential co‐benefits could be. These co‐benefits were scattered across environmental, economic, social and political issues, yet they may be summarised into six primary co‐benefits: developing natural capital, climate change mitigation, carbon trading, improvements in crop yield, animal performance and human health (nutrition). Additionally, the main barriers to improved soil management practices are centred on knowledge exchange‐regarding agri‐environmental techniques—whilst the most impactful solutions rely on soil monitoring, reporting and verification.
Food Energy Secur. 2021;00:e352.
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https://doi.org/10.1002/fes3.352
wileyonlinelibrary.com/journal/fes3
Received: 14 September 2021
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Revised: 2 December 2021
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Accepted: 3 December 2021
DOI: 10.1002/fes3.352
ORIGINAL ARTICLE
Potential Co- benefits and trade- offs between improved
soil management, climate change mitigation and agri- food
productivity
RyanMcGuire1
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Paul N.Williams1
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PeteSmith2
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Steve P.McGrath3
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DonaldCurry4
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IainDonnison5
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BridgetEmmet6
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NigelScollan1
This is an open access article under the terms of the Creat ive Commo ns Attri bution License, which permits use, distribution and reproduction in any medium, provided
the original work is properly cited.
© 2022 The Authors. Food and Energy Security published by John Wiley & Sons Ltd. and the Association of Applied Biologists.
1Queen's University Belfast, Belfast, UK
2Institute of Biological and
Environmental Science, University of
Aberdeen, Aberdeen, UK
3Rothamsted Research, Harpenden, UK
4House of Lords, London, UK
5Institute of Biological, Environmental
& Rural Sciences (IBERS), Aberystwyth
University, Aberystwyth, UK
6UK Centre for Ecology & Hydrology,
Wallingford, UK
Correspondence
Ryan McGuire, Queen's University
Belfast, Belfast, UK.
Email: r.mcguire@qub.ac.uk
Abstract
Maximising resource- use efficiency, productivity and environmental sustain-
ability are all fundamental requirements to raise global food production by
~70 per cent in order to feed a world population of ~9.7 billion people by 2050.
Perhaps the most vital resource within our capacity to achieve this goal is our
soil. Broadly, the fundamental question concerns whether or not satisfying this
production demand will accelerate soil degradation, climate change, and the
loss of soil carbon stocks. This paper builds upon the outputs of the UK Charity
‘Food & Farming Futures’ (chaired by Lord Curry of Kirkharle) virtual work-
shop held on 23March 2021, entitled ‘Capturing the Potential of Soil’. The event
focussed on the link between soil health, primarily soil organic carbon (SOC),
and agricultural productivity. Supported with commentaries by Professor Pete
Smith (University of Aberdeen and Science Director of the Scottish Climate
Change Centre of Expertise) and Professor Steve McGrath (Head of Sustainable
Agricultural Sciences at Rothamsted Research), specific focus will be given to the
research challenges within the UK’s ability to improve soil health and functional-
ity, the implementation priorities that must be held in order to improve soil man-
agement by 2050 and what the potential co- benefits could be. These co- benefits
were scattered across environmental, economic, social and political issues, yet
they may be summarised into six primary co- benefits: developing natural capital,
climate change mitigation, carbon trading, improvements in crop yield, animal
performance and human health (nutrition). Additionally, the main barriers to im-
proved soil management practices are centred on knowledge exchange- regarding
agri- environmental techniques— whilst the most impactful solutions rely on soil
monitoring, reporting and verification.
KEYWORDS
agriculture, climate change, environment, food security, soil management, sustainability
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INTRODUCTION
As a vital life- support system, the health of our soil is fun-
damental to the delivery of essential ecosystem services,
agricultural productivity (e.g. crop nutrition and animal
welfare), food security and environmental welfare [e.g.
ecological integrity, conservation, carbon sequestration
(balancing), etc.]. Nonetheless, when considering soil
health, one may decide to place emphasis upon key physi-
cal and chemical indicators of soil health, e.g. pH, organic
matter (soil organic carbon), nutrient indices (including
micro/macronutrients and trace elements) and porosity.
On the other hand, more emphasis may be placed upon
soil's role in sustaining and promoting natural capital,
ecosystem functionalities including socio- hydrology and,
in particular, plant and animal health and overall agricul-
tural productivity (see Doran and Parkin, 1994 and 1997;
Kibblewhite et al., 2008 and Bünemann et al., 2018).
Particularly since the green revolution, a time when
the world population was ~2.5 billion, at the centre of ag-
riculture's ability to satisfy global food demands has been
the predominance of land productivity through the ex-
ploitation of natural resources, primarily soils. Soils are
fundamental to the production of agricultural and horti-
cultural products, facilitating a myriad of crucial natural
services within crop and livestock production systems;
such services include plant growth, nutrient cycling and
regulation, pest and disease control, carbon sequestration/
greenhouse gas (GHG) regulation, habitat for biodiversity,
support of microbe health and overall ecosystem prosper-
ity (see Stockdale et al., 2018). Such services have enabled
soils to be the source of 98.8% of global food production
(Kopittke et al., 2019), whilst in the UK, agricultural pro-
duction from soils is worth £5.3bn per year (Parliament
House of Commons, 2016). Nonetheless, the world's pop-
ulation is projected to increase to ~9.7 billion people in
2050; therefore, feeding this growing population requires
raising global food production by ~70 per cent between
2005 and 2050 (Noel, 2016).
Agricultural intensification is likely to lead efforts in
satisfying this extra demand. However, further exploita-
tion of soils will raise significant concerns that this may
accelerate soil degradation (i.e. lossof soil organic mat-
ter and erosion), environmental harm (i.e. loss of genetic
diversity and acidification), climate change through the
release of GHGs (i.e. nitrous oxide and methane) and the
loss of soil carbon stocks— mostly through intensive till-
age practices (see Kopittke et al., 2019). For example, ac-
cording to Reynolds et al. (2013), degradation has led to
a loss of 11% in arable topsoil in Britain since the 1970s
(i.e. 0.4% loss per year), whilst in 2010, soil degradation
in England and Wales was estimated to cost £1.2 billion
a year (Lindsay, 2014). Simply put, for Kibblewhite et al.,
2008pg.685), ‘the major challenge within sustainable soil
management is to conserve ecosystem service delivery
whilst optimising agricultural yields’.
This paper builds upon the outputs of the UK Charity
‘Food & Farming Futures’ (chaired by Lord Curry of
Kirkharle) virtual workshop held on 23March 2021, en-
titled ‘Capturing the Potential of Soil’. The event focussed
on the link between soil health, primarily soil organic
carbon (SOC), and agricultural productivity. Specifically,
using the UK as an exemplar, this paper scrutinises the re-
search challenges that are facing government (especially
within developed nations) as they aim to improve soil
health and maximise productivity, the implementation
priorities that must be centralised and what the potential
co- benefits, barriers and solutions to improve soil man-
agement could be.
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RESEARCH CHALLENGES
Within the UK, cropland soilsare depletedin SOC (Smith
et al., 2007). One primary driver of this depletion has been
changes in land use. For example, a meta- analysis by Guo
and Gifford (2002) demonstrated that land- use change
from native forest to crop results in a ~40% reduction in
SOC concentrations whilst pasture to crop results in ~60%
reduction of SOC— primarily because of increased soil till-
age and reduced carbon inputs when changing to arable
farming. An article by Paustian et al. (2016) presented a
decision tree for cropland GHG mitigating practices.
Such decisions included, for example, land- use changes,
wherein ‘the most productive mitigation option for de-
graded or marginal lands is conversion to perennial veg-
etation’ (Paustian et al., 2016pg. 50). Moreover, a range
of managerial changes were also provided, in the form of
making recommendations on key practices to reverse soil
degradation or improve GHG mitigation potential. These
include reducing tillage intensity: implementing residue
retention, increasing N2- fixing legumes, multispecies
swards, and improving timing and placement of nutrient
applications using enhanced fertiliser application tech-
niques. These management changes are regularly im-
plemented in various parts of the world to increase soil
organic carbon levels, as outlined in case studies provided
by the FAO’s ‘Recarbonizing Global Soils (RECSOIL)’
programme in six volumes (FAO, 2021).
Looking specifically at the mitigation potential of soils,
carbon sequestration through SOC offers significant GHG
mitigation potential. SOC is found within soil organic
matter, which is a measure of all living organisms and
decomposing material (microbial biomass and microbial
activity). Loveland and Webb (2003) reported that an SOC
of 2% was equivalent to ca. 3.4% soil organic matter— this
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MCGUIRE et al.
wasthought to be the critical level at below which soil
properties are undermined— but this single value does
not hold across all soil types and climatic conditions.
Insufficient levels of SOC severely decreases the miti-
gation potential of soils. In relation to soil type, a front-
runner in sequestration potential (due to elevated levels
of soil organic matter) is peatlands. In the UK, peatlands
store around 3 billion tonnes of carbon but are emitting an
estimated 23million tonnes of carbon dioxide equivalent
(CO2e) annually (5% UK emissions) as a result of drainage
and degradation (Stafford et al., 2021).
Overall, an estimated 9.8 billion tonnes of carbon are
stored in Britain's soils (Parliament House of Commons,
2016). In 2013, GHG emissions from UK soils were
22.29million metric tonnes of CO2equivalent (MtCO2e).
In contrast, GHG removal by UK soils from the atmo-
sphere (carbon sequestration) amounted to 15.5MtCO2e
in the same year. This means that the net emissions from
UK soils were 6.75MtCO2e (UK soil carbon balance) in
2013— 1.45% of the UK’s total emissions (see Parliament
House of Commons, 2016). The sequestration potential of
peatlands is central to this balance, storing around 40% of
soil carbon— sequestering carbon 100 times faster than it
is emitted (Parliament House of Commons, 2016).
Globally, with improved soil management, particularly
increasing SOC levels, global sequestration potential of
SOC is equivalent to ~1.3 Gt Ceq/year. This sequestra-
tion is equivalent to around 5– 10% of annual global GHG
emissions. A variety of management practices exist to help
reach this target, for example, the restoration of histosols
(peatland restoration), grazing land management, crop-
land management and biochar application(Hardy et al.,
2019). Seminatural land has the highest concentrations of
SOC, primarily because (1) it is not disturbed or ploughed
and includes rough grazing land/grazing land and (2)
the semi natural land includes peaty soils— a larger car-
bon stock. Importantly, increasing SOC stocks not only
enhances climate change mitigation but also improves
the productivity of agri- food; globally, increasing SOC by
1MgC/ha may result in a yield increaseof 100– 300kg/ha/
Mg C for maize— and a potential increase of 30– 50mil-
lion tonnes of food production per year in developing
countries.
Further to this ‘win- win’ output, improving soil man-
agement may also result in an enhanced array of ecosys-
tem services— all positively linked to the UN Sustainable
Development Goals (SDGs). Smith et al. (2021) outlined
a plethora of such benefits, linking them to SDGs via a
network of ecological, economic and social subthemes,
for example, soil as a natural carbon pool, regulating air
quality and ocean acidification, contributing positively
to all SDGs. Despite the scale of these potential benefits,
one may argue that no service offered by soils has more
contemporary value than GHG mitigation, primarily
through carbon sequestration via SOC. However, it is im-
portant to note that SOC has significant sequestration po-
tential soon after a management change, but this declines
over time until it reaches saturation after 10– 100 years,
and most importantly, soil carbon storage is reversible and
highly sensitive to poor management.
Given that changes in soil carbon are relatively small
relative to large carbon stocks, and because soil carbon
levels change slowly, in order to fully harness the po-
tential of soil carbon sequestration, strong monitoring,
reporting and verification (MRV) protocols are required
(Smith et al., 2020), including direct measurement, mod-
elling, soil survey data, long- term experimental field tri-
als, remote sensing and statistical activity data to capture
management changes. Models of soil carbon turnover can
be developed, calibrated and evaluated with data from
long- term experiments, flux measurements and other in
situ observations. Well- tested models, driven by spatial
datasets of climate, soil characteristics, land use and land
management, can be used to complement in- field mea-
surements and to project likely changes in soil organic
carbon content in the future after a management change.
Farm survey data can be used to define management prac-
tices, and the model outputs can be verified by direct mea-
surement and remote sensing. By using all of these data
and information streams together, soil MRV can be made
more accurate and affordable (Smith et al., 2020).
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IMPLEMENTATION
PRIORITIES
In response to these challenges, there are multiple imple-
mentation priorities that government (especially within
developed nations) must hold in order to improve soil
management to maximise production and ecosystem de-
livery by 2050. However, it must first be noted that most
soil properties change quite slowly; therefore, sustainable
global soil management is dependent on a number of key
conditions: (1) evidence and prediction of what really
works; (2) models that are truly predictive of outcomes;
(3) agreed standards and certification for MRV and (4)
what is a ‘good level’ of SOC for a particular situation.
Building upon the major challenge of maintaining
and improving SOC, a key priority for the UK, for ex-
ample, particularly at the farm level, is raising SOC con-
centrations in cropland soils. Building upon research
by Poulton et al. (2018), who analysed SOC increases in
16 long- term experiments in the southeast of the UK,
a profile of strategies that can effectively improve SOC
stocks can be developed. According to Poulton et al.
(2018), the two strategies that increased SOC the most
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MCGUIRE et al.
within the topsoil were applications of farmyard ma-
nures (35 t/ha to soils with <2.5% org C) and sewage
sludge (sludge compost), with farmyard manures deliv-
ering SOC increases of 18‰ and 43‰ per year (23cm
depth) during the first 20years. The positive impact of
such strategies on SOC stocks was followed by increased
applications of compost, ley- arable, green manures,
straw and nitrogen fertiliser, with the latter an exam-
ple of a strategy that improves productivity, farm eco-
nomic performance and carbon sequestration. However,
as Poulton et al. (2018) pointed out, there are concerns
around the permanence and additionality of the SOC
that is sequestered. Inputs of organic carbon (OC) need
to be sustained to maintain higher SOC levels, and the
OC sources used must not be simply from one part of the
land to another, i.e. they must be additional to what is in
the system originally. Poulton et al. (2018) also pointed
out that in many systems, the organic residues such as
straw and others may already be returned to soils, and
that such residues are in short supply.
In addition, one must appreciate that there is a scar-
city of evidence within this area. Further research is re-
quired to address how much carbon, and for how long, is
required to achieve such changes in SOC levels in a range
of soils and situations, including climate and previous
management. To assess the potential for implementing
SOC increase, the following needs to be known: the cur-
rent (baseline) SOC, the soil type, whether SOC concen-
trations are close to an equilibrium, and the co- benefits.
Hijbeek et al. (2017) used meta- analysis to quantify the
additional yield effect due to organic inputs for arable
crops in Europe, the research found that although sur-
prisingly there were no significant impacts of increased
organic inputs on crop yields across all sites, there were
significances among spring- sown crops and crops that are
very sensitive to soil physical conditions: potatoes (mean
yield increase 7.0% ±4.9 – 95% c.i.) and maize (mean yield
effect of 4.0%±3.7 – 95% c.i.).Relatively small increases
in SOC rather than large ones may in fact be beneficial
for some crops, through improving the soil structure and
general soil health (Poulton et al., 2018).
When aiming to establish a good level of SOC, the
SOC to clay ratio is often used in research. Prout et al.
(2020) used this ratio to assess SOC concentrations across
3,809sites using data from the National Soil Inventory of
England and Wales— with thresholds of 1/8, 1/10 and 1/13
(SOC/clay) indicating the boundaries between ‘very good’,
‘good’, ‘moderate’ and ‘degraded’ levels of structural con-
dition. Whilst variables such as land use, soil type, annual
precipitation and soil pH explained significant variance
in SOC/clay ratio, using this scale, the research revealed
that38.2, 6.6 and 5.6% of arable, grassland and woodland
sites, respectively, were degraded— with most of these
degraded soils found in eastern and southern areas (see
Prout et al., 2020). Ultimately, the optimum SOC can be
a challenge, as it depends on how different soil functions
are valued (FAO, 2017). Additionally, it is noteworthy that
there is no ‘critical threshold’ of SOC, although a ratio of
1:10 SOC/clay is widely considered "good" but more could
be "better". But at higher ratios, the SOC present tends to
be less well protected and is more susceptible to losses (re-
versal of SOC gains).
Despite the above, there are limitations regarding the
standards for monitoring, reporting and validating levels
of SOC; current knowledge remains limited regarding
SOC baselines and changes, the detection of vulnerable
hot spots for SOC losses and the situations that provide the
greatest opportunities for SOC gains under both climate
and land management changes. There is no agreement
in SOC monitoring schemes, and this may already lead
to carbon credits that are not at all comparable (Oldfield
et al., 2021). Ideally, to resolve these challenges, an assess-
ment of the mitigation potential of agricultural practices
at both local and national levels is required, using com-
mon protocols, coupled with the implementation of miti-
gation options in an emission trading/market mechanism.
Importantly, solutions are conditional on accurate and
quantifiable techniques. Indeed, a report by the FAO in-
troduced an international approach for measuring and
modelling SOC stocks from grasslands and rangelands—
placing emphasis on carbon sequestration gains/losses
within livestock supply chains (FAO, 2019). The report
outlined a wide range of conditions that need tobe ful-
filledin order to gain a thorough understanding of SOC
stocks and changes. For example, a soil sampling strat-
egy should encompass the following features: allow for
climate, soil type, hydrology, topography, land use, man-
agement and land- use history; minimum measurement
requirements, a sampling depth of at least 30cm; changes
in soil bulk density as SOC increases need to be accounted
for and all samples georeferenced. For repeated mea-
surements, sampling should typically occur at least 4 to
5years apart because soil carbon changes slowly in most
situations.
In summary, many of the practices are already known
but now need rapid implementation, which requires
change in the way agricultural soils are managed, and in
farm businesses. Research is needed in the area of soil in-
formation and assessment, to produce information upon
which management decisions can be made accessible and
affordable to farms. The priorities for implementation of
current knowledge and future innovations in agricultural
systems need to be based around sustainable soil manage-
ment principles (FAO, 2017) but also depend heavily on
parallel policy and socio- economic factors to support im-
plementation. In general, these now come under the wide
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MCGUIRE et al.
banner of ‘regenerative agriculture’, and the following ac-
tivities urgently need to be funded and promoted:
1. Protecting and increasing existing carbon stores in
permanent grasslands, moorlands, wetlands and
woodlands
2. Minimizing soil disturbance by avoiding mechanical
tillage through adoption of conservation tillage and no-
till systems. Enhancing and maintaining a protective
organic cover on the soil surface using cover crops and
crop residues.
3. Enhancing crop nutrition through balanced measures
that include crop rotations with N- fixing crops, judi-
cious use of organic and inorganic fertilisers, and tar-
geted amendments such as lime to address specific soil
chemical conditions such as high acidity, which limit
primary production in some regions.
These apply worldwide but will need urgent efforts to
attain because of the largely fractured nature of the farm-
ing industry, especially in developing counties with many
smallholder farmers. In the UK, this will be promoted
through new policies that include ‘payments for public
goods’ to farmers (UK Government, 2020).
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POTENTIAL CO- BENEFITS,
BARRIERS AND SOLUTIONS
Thus far, focushas been placedon the range of challenges
and the subsequent priorities the UK must tackle and im-
plement to maximise productivity and ecosystem delivery
through improved soil management by 2050. Yet, if this
is done successfully, the plethora of potential co- benefits
may be categorised into the three primary dimensions
of sustainability (Figure 1 for an illustration of benefits
from a soil management wide range of practices, whilst
Table 1 focusses on practices increasing SOC). Firstly, a
surplus of environmental and ecological benefits must be
acknowledged including reducing soil nutrient deficien-
cies, improved nutrient cycling (geological and biological
processes), erosion reduction, improvements in biodiver-
sity and species conservation. For example, looking specif-
ically at SOC, gains in microbial community structure and
increasing oxidation by methane- oxidising bacteria (Tveit
et al., 2019) are associated with building SOC. In addition,
there would also be improvements in water regulation,
minimization of pollutions and soil contamination, whilst
improving SOC concentrations reduces supplementary
inputs required to sustain/improve productivity, e.g. arti-
ficial/synthetic fertilisers.
Whilst flood mitigationwas identifiedas a major co-
benefit, in turn, this co- benefit would result in a longer
growing capacity for crops because of improved resilience
and, what is more, this could improve crop yield and ag-
ricultural productivity. Moreover, soils are a major source
of global food production; therefore, improving the health
of our soils, both physically and chemically will bolster
its productivity whilst resulting in enhanced ecosystem
services, healthier plants, healthier diets and, ultimately,
a healthier global population.
Furthermore, although ~21– 37% of total global GHG
emissions are attributable to the food system and 10– 14%
are attributable to agriculture (mean of 2007– 2016 pe-
riod) (Mbow et al., 2017), it should be recognised that a
major and urgently required co- benefit of improved soil
management is climate change mitigation— by lowering
global net GHG emissions through carbon sequestration
via increases in SOC— a process which can be accelerated
by livestock grazing through sustainable production sys-
tems (see Reeder & Schuman, 2002). For such systems, ex-
amples of sustainable practices would include the use of
N2- fixing legumes, growing multispecies swards and peat-
land restorations. These practices, as outlined in Table 1,
can improve crop yield, farm productivity and help satisfy
global food demands.
Especially among arable farms, the adverse impacts of
tillage on SOC stocks along with potential benefits of re-
duced intensity tillage practices are well documented (see
Schimel et al., 1985; Elliott, 1986 and DeLuca & Keeney,
1994; Sun et al., 2011 and Mehra et al., 2018).The benefits
of reduced tillage go beyond reducing SOC loss and restor-
ing stocks, and there are also financial gains of reduced
dependence on intensive labour and resource units (i.e.
machine usage), thereby improving key indicators of busi-
ness economic performance including labour productivity
and resource- use efficiency. At the centre of the financial
co- benefits of improved soil management, SOC stocks and
subsequent carbonsequestration potential are the posi-
tion of agriculture within an agricultural emission- trading
scheme. Such schemes would enable farmers to enter pri-
vate markets to improve business competitiveness using a
universal currency.
This currency would enable farmers to purchase and
sell carbon credits to offset net GHG emissions and/or im-
prove long- term business profitability, economic indepen-
dence and net income (see McHenry, 2009). Most notably,
aside from the benefits of a carbon market, improved soil
management through smart data- informed techniques
such as GPS soil sampling, precision nutrient applications
and low- emission slurry spreading techniques (see Amon
et al., 2006; Misselbrook et al., 2002; Webb et al., 2005 and
Webb et al., 2010) offers significant potential for improve-
ments in crop nutrition and yield, which in turn, will
offer significant improvements in gross profits per hectare
among both arable and livestock production systems.
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MCGUIRE et al.
Whilst the environmental and subsequent economic
benefits of improved UK soil management are clear, there
are also a number of fundamental and unique societal
benefits at the individual (including farm), local, national
and global levels. Probably, the most obvious benefit is the
improved capacities of UK soils to strengthen food secu-
rity through improvements in climate change resilience,
crop yield, animal health and welfare, product quality
and overall sustainability at regional, national and global
levels. Moreover, public health and nutritional benefits
may include dietary improvements, pest and disease con-
trol and the link between climate change mitigation and
the environmental and societal determinants of health–
including physical, social and mental health (Friel et al.,
2009). More locally, the immediate recipients’ benefits of
soil management improvements are the farmers them-
selves. Overlapping economic gains result in a wide range
of socio- economic benefits to farmers through improved
farm income, resulting in improved farm business invest-
ment, reduced health and safety risk, better animal and
FIGURE Potential Co- benefits of Improved Soil Management by 2050
Improv ed UK Soil
Management
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MCGUIRE et al.
crop performance, quality of life for farmers and overall
farm- family well- being.
It is clear that if government take effective action to
improve soil management, the co- benefits range greatly.
Nonetheless, it is noteworthy that they may be summarised
into six primary co- benefits: developing natural capital,
climate change mitigation, carbon trading, improvements
in crop yield, animal performance and human health
(nutrition) (Figure 1). Additionally, given the extent and
quality of science reinforcing the best practices to improve
soil health, the main barriers are centred on knowledge
exchange regarding agri- environmental techniques; the
translation of scientific outputs into practical on- farm
techniques and developing strategic and methodical plans
better inform farmers of measures to improve soil health
and reach NetZero. Importantly, this study finds that the
most important remedies to help overcome such chal-
lenges rely on soil monitoring, reporting and verification;
this includes high- quality data collection, investments in
innovation and the creation and development of data-
driven knowledge hubs (two- way) between farmers and
policy makers— with evidence- based scientific communi-
cation at the centre.
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CONCLUSION
Government must look beyond the immediate benefits of
satisfying global food demands,which focus less on en-
vironmental/ecological welfare and establish long- term
sustainable solutions that meet production urgencies with
zero environmental cost— or ideally facilitate environ-
mental/ecological restorations with economic and social
benefits. Importantly, although intensifying UK agricul-
tural practices poses many environmental threats, includ-
ing soil degradation, if practiced sustainably, there are
many potential benefits of approaches that positively im-
prove soil management and soil quality, such as ‘sustain-
able intensification’ or ‘regenerative agriculture’.
The principal outcome of the ‘Capturing the Potential
of Soil’ workshop has been the identification of such
practices, subsequent benefits and the main barriers pre-
venting the agri- food sector from implementing these
practices. This paper has demonstrated that whilst poten-
tial barriers are centred on knowledge exchange regard-
ing agri- environmental techniques, solutions are highly
dependent on soil MRV, high- quality data collection and
investments in innovation.
Specifically, at the farm level, these solutions include
soil management practices such as precision farming, dig-
ital innovation, reduced tillage, incorporate cover crops,
green manures and other sources of organic matter to
improve soil structure and levels of SOC, more N2- fixing
TABLE A profile of key soil management practices and the significance of their potential impact on indicators of environmental, economic and social sustainability
Soil management
practice
Environmental (climate) Economic Societal
Climate change
mitigation
Improved
crop yield
Better animal
performance Natural capital
Resource- use
efficiency Net income Public health
Global food
demands
1. MRV (measure, report
verification)
++ ++ ++ + ++ ++ + ++
2. Reduced tillage ++ + + + + + + +
3. N2- fixing legumes ++ + + + + ++ + +
4. Multispecies swards ++ ++ ++ ++ ++ ++ + +
5. Improved fertiliser
applications
+ ++ ++ + ++ + ++ ++
6. Peatland restoration ++ ~ ~ ++ + + + ~
7. Grazing land
management
+ ++ ++ + ++ ++ + +
8. Organic fertiliser
applications
++ ++ + + + + + ~
Note: ++, Significant improvement; +, Minor improvement; ~, Neutral.
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MCGUIRE et al.
legumes, multispecies swards, species conservation to
improve ecosystem performance and maximisation
(and measurement) of aboveground biomass. Moreover,
co- benefits were scattered across environmental, eco-
nomic,social and political issues and included six primary
co- benefits: developing natural capital, climate change
mitigation, carbon trading, improvements in crop yield,
animal performance and human health (nutrition).
It is noteworthy, the aforementioned soil manage-
ment practices are at the centre of current and emerg-
ing agri- environmental policies at both the national and
pan- European levels, for example, the European Green
Deal, Farm to Fork Strategy, Horizon Europe (2030), the
UK Agriculture Bill (2020) and the Environmental Land
Management Scheme. Statutory requirements of such
polices share one primary goal: targeting on- farm cli-
mate change mitigation and adaptation techniques and
the integration of increased agri- food production with
environmental remediation, animal welfare and public
well- being— one principle model of global health. More
specifically, given that agriculture is responsible for
~10% of UK and ~10– 12% of global GHG emissions, cli-
matechange is at the core of these targets. Yet, it is note-
worthy, that many, if not all, of the practices centred on
improved soil management (i.e. precision farming, etc.)
outlined in this paper are not only drivers of improved
productivity but are also examples of highly effective cli-
mate change mitigation strategies (Table 1).
Most importantly, the narrative of these practices and
subsequent benefits are subject to strategies of MRV, the
need to improve the evidence base of the potential of im-
proved soil management for ecosystem services and the
overall environmental, economic and social benefits—
linked through the SDGs. It is also important to reinforce
that improvements in soil management will not resolve
major environmental urgencies alone; they must work
in harmony with other mitigation techniques. Such tech-
niques must be integrated across the supply chain; yet, at
the farm level, these include energy efficiency, maximis-
ing aboveground biomass, investment in renewables, low-
emission nutrient applications and dietary shift among
ruminants to reduce methane emission and nitrogen
excretion.
Nonetheless, the current study finds that improved
soil management does offer a vital contribution to climate
change mitigation potential if combined with other stra-
tegic approaches to help achieve net zero. Examples of
such approaches may include the use of alternative feeds
(e.g. through gut microbial programming or dietary sup-
plements and home- grown feeds), smart technology and
precision livestock farming (e.g. animal genotyping and
phenotyping, land use and manure management), en-
hanced calculation methods (controlling for differences
in different GHGs) and improved education, knowledge
exchange and adoption of whole- farm sustainability met-
rics. Nonetheless, there is a need by industry to implement
the knowledge we have now, incentivised through appro-
priate policies, whilst science continues to increase our
understanding of land- use patterns and environmental
processes that contribute to changes in soil carbon to en-
sure that agriculture can play an important part in achiev-
ing climate change targets.
ACKNOWLEDGEMENTS
RMG is supported through the UK Research & Innovation
Biotechnology and Biological Sciences Research
Council. RMG is the UK lead representative of the Joint
Programming Initiative on Agriculture, Food Security and
Climate Change (FACCE JPI) on the Modelling European
Agriculture with Climate Change for Food Security:
Science-Policy Knowledge Forum (MACSUR SciPol).
ORCID
Ryan McGuire https://orcid.org/0000-0003-1602-3533
Pete Smith https://orcid.org/0000-0002-3784-1124
Steve P. McGrath https://orcid.org/0000-0003-0952-8947
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