Regenerative agriculture – the soil is the base

Abstract

Regenerative agriculture (RA) is proposed as a solution towards sustainable food systems. A variety of actors perceive RA differently, and a clear scientific definition is lacking. We reviewed 28 studies to find convergence and divergence between objectives and activities that define RA. Our results show convergence related to objectives that enhance the environment and stress the importance of socio-economic dimensions that contribute to food security. The objectives of RA in relation to socio-economic dimensions, however, are general and lack a framework for implementation. From our analysis, we propose a provisional definition of RA as an approach to farming that uses soil conservation as the entry point to regenerate and contribute to multiple ecosystem services.

Full text

Global Food Security 26 (2020) 100404
Available online 6 August 2020
2211-9124/© 2020 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).
Regenerative agriculture – the soil is the base
L. Schreefel
a
,
b
,
c
,
*
, R.P.O. Schulte
b
, I.J.M. de Boer
c
, A. Pas Schrijver
b
, H.H.E. van Zanten
c
a
TiFN, P.O. Box 557, 6700, AN, Wageningen, the Netherlands
b
Farming Systems Ecology Group, Wageningen University & Research, P.O. Box 430, 6700, AK, Wageningen, the Netherlands
c
Animal Production Systems Group, Wageningen University & Research, P.O. Box 338, 6700, AH, Wageningen, the Netherlands
ARTICLE INFO
Keywords:
Regenerative agriculture
Circular agriculture
Organic agriculture
Soil health
Literature review
Cultural domain analysis
ABSTRACT
Regenerative agriculture (RA) is proposed as a solution towards sustainable food systems. A variety of actors
perceive RA differently, and a clear scientic denition is lacking. We reviewed 28 studies to nd convergence
and divergence between objectives and activities that dene RA. Our results show convergence related to ob-
jectives that enhance the environment and stress the importance of socio-economic dimensions that contribute to
food security. The objectives of RA in relation to socio-economic dimensions, however, are general and lack a
framework for implementation. From our analysis, we propose a provisional denition of RA as an approach to
farming that uses soil conservation as the entry point to regenerate and contribute to multiple ecosystem services.
1. Introduction
The global food system currently releases about 25% of annual
anthropogenic greenhouse gas (GHG) emissions, causes about one-third
of terrestrial acidication and is responsible for the majority of global
eutrophication of surface waters (Poore and Nemecek, 2018). If our food
system continues with current practices, using synthetic pesticides,
articial fertilizers, fossil fuels and producing food waste, the carrying
capacity of the planet is likely to be surpassed (Campbell et al., 2017).
Therefore, the key challenge for humanity is to produce enough safe and
nutritious food for a growing and wealthier population within the car-
rying capacity of the planet (Willett et al., 2019). The importance of
producing food within the carrying capacity of the planet is also
increasingly acknowledged in policies - for example, the EU Circular
Economy Action Plan (European Commission, 2015), the Paris Climate
Agreement (United Nations, 2015) and the Common Agricultural Policy
(European Commission, 2019a).
This challenge has led to new narratives for sustainable agriculture.
Some of these narratives are production-oriented and nd their solutions
in approaches such as sustainable intensication, which explores
increased production yields to reduce the environmental impact (Cole
and McCoskey, 2013; Garnett et al., 2013). Another narrative argues
that the production-oriented approach is not sufcient to deal with the
key challenge for humanity and that consumption patterns should be
adjusted for the global food system to function within the boundaries of
our planet (Garnett et al., 2013; Stehfest et al., 2009; The Eat-Lancet
Commission, 2019; Tilman and Clark, 2014). Building on both the
production and consumption-oriented approaches for example Van
Zanten et al. (2018) argues that production and consumption-oriented
approaches are needed together and should be in balance with their
ecological environment. Their narrative takes a food systems perspec-
tive and aims at safeguarding natural resources by closing of nutrients
and carbon cycles in the food system as far as possible, also referred to as
a circular food system (de Boer and van Ittersum, 2018).
Farming approaches within these narratives often share similar de-
sires to reach an objective, such as achieve global food security, reduced
use of external inputs and reduced environmental damage. Some of
these farming approaches have denitions that are comprehensively
described in the scientic literature and regulated, for example, organic
agriculture (European Commission, 2019b; IFOAM - Organics Interna-
tional, 2019), climate-smart agriculture (FAO, 2018) and sustainable
intensication (FAO, 2013), while others remain yet as theoretical and
mainly scientic concepts such as circular agriculture. An approach that
recently gained attention in the literature as a solution for a sustainable
food system is regenerative agriculture (RA) (LaCanne and Lundgren,
2018; Shelef et al., 2017). Currently, RA does not have a comprehen-
sively described scientic denition (Elevitch et al., 2018).
In absence of such a scientic denition, a variety of researchers may
foster diverging perceptions of RA. For example, Malik and Verma
(2014) describe RA as dynamically advanced modied technique
involving the use of organic farming methods, while Elevitch et al.
(2018) describe RA as a farming approach that has the capacity for
* Corresponding author.
E-mail address: loekie.schreefel@wur.nl (L. Schreefel).
Contents lists available at ScienceDirect
Global Food Security
journal homepage: www.elsevier.com/locate/gfs
https://doi.org/10.1016/j.gfs.2020.100404
Received 19 March 2020; Received in revised form 17 June 2020; Accepted 29 June 2020

Global Food Security 26 (2020) 100404
2
self-renewal and resiliency, contributes to soil health, increases water
percolation and retention, enhances and conserves biodiversity, and
sequesters carbon. Therefore, in this review, we assess the background
and core themes of RA by examining the convergence and divergence
between denitions in peer-reviewed articles. An assessment of the
background and core themes of RA allows the establishment of an
evidence-based provisional denition. Such a denition forms a basis for
further discussion not only within science but also among a large group
of actors (e.g. governmental agencies, sector organisations, industries
and farmers). This large group of actors may foster different denitions
dependent on their particular interests. A provisional denition is,
therefore, essential to establish a common denition in which more
views are included and indicators that enables actors to assess their
performance towards a sustainable food system. Indicators, for example,
enables governments and industries to monitor their performance to-
wards the Sustainable Development Goals (SDG’s), it enables policy-
makers to create supporting policies for actors in the eld, it enables
researchers to have a scientic basis to accumulate knowledge and it
enables farmers to assess which activities to adjust. To illustrate the
convergence between sustainable farming approaches we relate RA to
organic agriculture as an example of a regulated farming approach and
circular agriculture which remains yet a theoretical concept.
2. Materials and methods
We systematically studied peer-reviewed articles to nd denitions
of RA using the methodological framework PRISMA-P (Preferred
Reporting Items for Systematic Reviews) (Shamseer et al., 2015). A
checklist of the suggested items reported in PRISMA-P is given in sup-
plementary materials A and a detailed overview of the review and
analytical process is presented in supplementary materials B. Five
journal databases (Scopus, Web of Science, Agricola, CAB Abstracts and
Medline) were searched for denitions of RA in December 2019. Key-
words used to create a search string to nd articles that include a de-
nition for RA build upon the words ‘regenerative’ and ‘farming’ (see
supplementary materials B10). For ‘farming’ different synonyms were
used, including agriculture, agronomy and food system. Search terms
such as ‘agronomy’ and ‘food system’ were included to capture deni-
tions for RA embedded in the transition towards a regenerative food
system.
The database search yielded 279 articles mentioning ‘regenerative’
and ‘farming’ (see Fig. 1). These 279 articles were screened on their
abstract and titles and narrowed down to 43 articles. The eligibility
criteria to narrow down articles based on their titles and abstracts were
to exclude: duplicates, unavailable articles within the selected data-
bases, articles which were not peer-reviewed and articles unrelated to
agriculture. After excluding fteen articles which did not contain a
denition of RA, 28 articles (Supplementary materials C) remained for
further synthesis. Reference checking using the snowballing technique
(Jalali and Wohlin, 2012) did not yield more articles. No articles were
excluded based on the year of publication. The PRISMA workow in the
supplementary materials D provides a more extensive overview of the
methodical process of inclusion and exclusion of articles.
We analysed the background (e.g. actor and scale to which the
denition applies) and different denitions of RA in the reviewed arti-
cles using a cultural domain analysis and inductive coding. A cultural
domain analysis (Borgatti, 1994) and inductive coding (Thomas, 2006)
are both synthesis methods to cluster segments of text, based on their
coherence. Following these methods, the denitions were split-up into
text segments called issues (e.g. improve soil carbon, minimize tillage).
These issues were categorised into objectives (e.g. improve soil carbon,
interspecies equity) and activities (e.g. minimize tillage, use natural pest
control). In this review, objectives capture the desire of researchers to
achieve a certain goal, whereas activities capture operationalizations,
for example, suggested farm practices. If these objectives or activities
were mentioned at least ve times in the literature, then we grouped
them into themes (e.g. improve soil physical quality, improve human
health). The criterion to have at least ve convergent objectives or ac-
tivities to form a theme was based on a sensitivity analysis (see sup-
plementary materials B15c, in which different numbers (3 till 7) of
convergent issues were assessed on their inclusiveness of specic
themes. The allocation process of issues was done by all co-authors
independently to reduce interpretation bias, and any disagreement on
the allocation of issues was solved by discussion. Supplementary mate-
rials E shows the allocation framework used. All the different themes
together form the core of RA. The following four aspects were analysed
to determine the themes of RA: i) the number of articles referring to the
themes, ii) the number of converging and diverging interpretations of
nomenclature within themes, iii) the classications of themes among
objectives or activities and iv) the relation of themes with the three
dimensions of sustainability, i.e. people, planet and prot (Elkington,
1997). Converging themes indicate that authors of different articles
Fig. 1. Illustration of the research methodology to analyse existing denitions of regenerative agriculture, in which ‘n’ represents the number of search records.
L. Schreefel et al.

Global Food Security 26 (2020) 100404
3
present similar objectives within their denitions. Diverging themes
present contradictions or issues which are unclear. The triple bottom
line approach (people, planet and prot) was used to categorize themes
among social (e.g. maintain cultural diversity), environmental (e.g.
improve soil structure) and economic (e.g. create long-term economic
sustainability) aspects (Elkington, 1997; Slingerland et al., 2003).
Furthermore, we analysed whether denitions were based on the ob-
jectives of researchers or farmers and to which scale (farm, regional or
systems-level) they relate. Fig. 1 illustrates the steps required to analyse
the existing denitions of RA.
3. Results and analysis
3.1. The core themes of regenerative agriculture
In the 28 peer-reviewed articles we found that denitions addressed
different issues (e.g. soil health, climate change) and scales (e.g. farm,
food systems-level), resulting in different levels of implementation. Our
review yielded 214 objectives and 77 activities. The assessment of the
convergence among objectives and activities, which was based on the
underlying issues, resulted in thirteen themes for objectives and seven
themes for activities (Fig. 2).
These twenty themes referred mostly to the environmental dimen-
sion of sustainability (seventeen out of nineteen). Environmental issues
were addressed from farm to food systems-levels (Fig. 2). Of these, all
activities and four objectives specically focussed on soil issues: enhance
and improve soil health, improve soil carbon, improve soil physical quality
and improve (soil) biodiversity. The multiple aggregation levels and
quantity of articles referring to environmental issues indicated that RA
focusses specically on environmental issues, and in particular soil
issues.
We will rst discuss the environmental themes that show most
convergence among denitions (see section 3.2), followed by themes
with divergence (see section 3.3). The specic issues among the themes
can be found in supplementary materials E.
3.2. Themes in RA showing convergence
All reviewed articles related RA with the environment (planet) and
mainly with improving environmental issues, which is referred to as
regenerate the system, reduce environmental externalities and improve the
ecosystem. Convergent objectives were mentioned regarding reducing
environmental externalities e.g. ‘reduce environmental damage’ (Tea-
gue, 2018, P.1520) and ‘reduce environmental pollution’ (Rhodes,
2012, P.345). Similarly, there was convergence about the improvement
of the ecosystem. A healthy agroecosystem was referred to as a resilient
ecosystem that enables the provision of ecosystems services, such as
provisioning, regulating, habitat and supporting services (e.g. Gosnell
et al., 2019; Rhodes, 2017; Teague, 2017). These three environmental
themes were further articulated by four themes that refer to the
improvement of the food system: enhance and improve soil health (n =
15), optimize resource management (n =13), alleviate climate change (n =
8) and improve water quality and availability (n =5).
The theme enhance and improve soil health received most attention;
seventeen of 28 articles explicitly mentioned improving soil quality in a
variety of synonymous objectives, such as ‘improve soil quality’ (Mahtab
and Karim, 1992, P.54), ‘contribute to soil fertility’ (Elevitch et al.,
2018, P.2), ‘enhance soil health’ (Sherwood and Uphoff, 2000, P.86) and
‘improve their soils’ (White and Andrew, 2019, P.2). A synthesis of the
issues among the objective to improve soil quality is that a healthy soil is
the basis for RA and therefore degraded agricultural soils should be
restored to healthy soils. This is expressed by, for example, Rhodes
(2012, P.380) who mentioned that RA ‘regenerates the soil’ and by Diop
(1999, P.296) who mentioned that RA ‘gives the soil as a resource the
rst priority’.
Thirteen out of 28 studies mentioned objectives to optimize resource
Fig. 2. The core themes of regenerative agriculture, in which ‘the number between brackets’ represents the number of search records.
L. Schreefel et al.

Global Food Security 26 (2020) 100404
4
management. Reviewed articles highlight objectives towards recusing
waste and optimal nutrient availability. They indicated RA as a system
which has the objective to regenerate resources in an integrated manner
for sustained soil fertility and desired crop and animal productivity.
They mentioned, for example, issues as ‘minimize waste’ (Teague, 2015,
P.5), ‘synergisms in different combinations and methods of manage-
ment’ (Teague and Barnes, 2017, P.80), ‘regeneration of natural re-
sources’ (Teague, 2015, P.5), ‘improve nutrient retention and
availability’ (Diop, 1999, P.295) and ‘encompass solid-waste manage-
ment’ (Mahtab and Karim, 1992, P.54).
Themes alleviate climate change and improve water quality and avail-
ability received less attention compared to other themes with objectives.
Moreover, eight of 28 articles have the objective to alleviate climate
change. Studies mentioned for example to ‘reduce GHG emissions’
(Teague, 2018, P.1520), ‘invert carbon emissions of our current agri-
culture’ (Elevitch et al., 2018, P.2) and ‘mitigate climate change’
(Rhodes, 2012, P.434). Similarly, ve of the 28 studies mentioned issues
supporting the theme of improve water quality and availability. For
example, to ‘improve water quality’ (Elevitch et al., 2018, P.4), ‘achieve
clean and safe water runoff’ (Elevitch et al., 2018, P.2), ‘reduce water
shortages’ (Rhodes, 2012, P.380) and ‘protect freshwater supply’
(Rhodes, 2017, P.95). Other studies did not mention such objectives
about the alleviation of climate change or the improvement of water
quality and availability.
The objectives enhance and improve soil health that received most
attention were further articulated by more specic objectives which
include improve (soil) biodiversity (n =17), improvement of soil carbon (n
=13) and soil physical quality (n =11). An objective frequently
mentioned (13 out of 28) is to improve (soil) biodiversity for improved soil
functioning, which relates to above and below ground biodiversity. The
issues among this theme showed convergence, although different issues
are mentioned in the reviewed articles: the improvement of soil biodi-
versity by ‘promoting soil biology’ (LaCanne and Lundgren, 2018, P.7)
or more general statements such as ‘increase the biodiversity’ (de Haas
et al., 2019, P.548). Although biodiversity is clearly an important theme,
it remains unspecied what is meant with the improvement of biodi-
versity (below or above-ground biodiversity, to which scale does it
relate). Most studies expect or assume, however, that RA will improve
biodiversity, which in general is seen as a precondition for a sustainable
food system.
Another objective which shows convergence and is frequently
mentioned (13 out of 28) is to improve soil carbon, articulated in the
reviewed article as for example ‘build soil organic matter’ (e.g. Diop,
1999, P.290; Rhodes, 2017, P.100), and ‘increasing carbon sequestra-
tion’ (e.g. Elevitch et al., 2018, P.2; Provenza et al., 2019, P.3; Sambell
et al., 2019, P.3). The improvement of soil carbon is considered a
cross-cutting issue across the three spheres of soil science (soil chemis-
try, soil physics and soil biology) since it affects all three aspects (Ontl,
2018). Improving soil carbon levels affects, for example, soil structure
and porosity; water inltration rate and moisture holding capacity of
soils; biodiversity and activity of soil organisms; and plant nutrient
availability (Bot and Benites, 2005).
The last objective related to enhance and improve soil health is to
improve soil physical quality. Similarly, to the previous theme, eleven of
28 articles mentioned improving soil physical characteristics and
reducing threats to soil quality. Examples of improvements in soil
physical characteristics include ‘improvement of water inltration’
(Teague, 2017, P.348), ‘improvement of water holding capacity’ (Diop,
1999, P.290) and ‘improvement of soil aeration’ (Teague, 2018,
P.1528). Mitigation of soil threats included ‘minimizing erosion’
(Francis et al., 1986, P.70), ‘improving soil structure’ (Rhodes, 2017,
P.123) and ‘reducing soil degradation’ (Rhodes, 2012, P.345).
An underlying theme of optimize resource management is to improve
nutrient cycling. Twelve out of 28 articles mentioned convergent issues
regarding nutrient cycling and these articles share the ambition to work
towards closed nutrient loops. Examples are ‘improve nutrient cycling’
(Teague and Barnes, 2017, P.1527), ‘tendencies towards closed nutrient
loops’ (Mitchell et al., 2019, P.7) and ‘more on-farm recycling’ (Teague,
2015, P.5).
In addition to objectives, most of the reviewed articles (20 of 28) also
mentioned activities to dene RA (Fig. 2). Activities showing conver-
gence in the literature are for example minimizing external inputs (e.g.
Lockeretz, 1988; Rhodes, 2017), minimizing tillage (e.g. Francis et al.,
1986; LaCanne and Lundgren, 2018), using mixed farming (Diop, 1999;
LaCanne and Lundgren, 2018), improving crop rotations (e.g. Francis
et al., 1986; Rhodes, 2012), and using manure and compost (Diop, 1999;
Rhodes, 2017). These activities direct towards a food system that builds
on its ecological cycles and as a co-benet reduces environmental ex-
ternalities. The suggested activities promote the integration of
crop-livestock operations (e.g. Dahlberg, 1994; Diop, 1999), in which
animals are primarily valued for their capabilities to build soil, besides
their role in producing food and bre (Teague et al., 2016). Livestock
breeds are, therefore, chosen for their compatibility with their local
environment (Gosnell et al., 2019; Steenwerth et al., 2014). The sug-
gested activities also shift from single to multi-cropping systems (e.g.
Francis et al., 1986), in which the use of perennials is favoured over
annuals (e.g. Elevitch et al., 2018; LaCanne and Lundgren, 2018),
because perennials have more extensive and deeper root systems and
don’t leave elds fallow in between growing seasons. Therefore, pe-
rennials are more resilient to weather extremes (LaCanne and Lundgren,
2018), reduce soil erosion (Pimentel et al., 1997), reduce nutrient runoff
(Teague, 2018), improve water conservation (Glover et al., 2010) and
carbon sequestration (Elevitch et al., 2018). Relying on ecological cycles
also resulted in a preference for animal manures over articial fertilizers
(e.g. Pearson, 2007), and for the use of natural pest control over syn-
thetic pesticides (e.g. Rhodes, 2017). Minimizing tillage is a specic crop
management technique valued to reduce soil disturbance, due to the
absence of heavy tillage machinery, allowing earthworms to aerate the
soil and increase nutrient distribution (Shah et al., 2017). Activities
among the theme ‘other soil conservation practices’ did not necessarily
represent divergence, however they presented various activities that
were not clustered as a separate theme, such as the use of windbreaks
(Diop, 1999), silvopasture (Elevitch et al., 2018), and managed grazing
(Provenza et al., 2019). These activities are in line with the objectives of
RA, without being clustered into separate themes.
3.3. Themes in RA showing divergence
Although the reviewed articles may show convergence upon most of
the themes, we can discern three themes showing a degree of diver-
gence: regenerate the system, improve human health and improve economic
prosperity. These themes show divergence because they embrace a sum
of issues which do not meet the requirement of at least ve convergent
issues to form a separate theme.
One of the key objectives of RA is that it is part of a regenerative
system. A large number of articles (15 out of 28) referred to environ-
mental objectives regarding the theme regenerate the system. A total of
fourteen environmental objectives showed that RA is aimed towards
productive agriculture that focusses on the health of nature through the
regeneration of the resources the system requires (e.g. energy, water,
nutrients and carbon). The objectives within this theme remain rather
vague because the reviewed articles did not dene what is meant by
objectives such as RA: should be able to ‘restore earth’ (Shelef et al.,
2017, P.2), ‘regenerates the natural system’ (Dahlberg, 1994, P.173) and
creates a ‘long-term rehabilitative strategy’ (Diop, 1999, P.296). Such
objectives may require a more elaborate description of, for example, the
capture of socio-economic aspects and how such objectives can be
implemented.
The theme improve human health relates to the objectives to provide
goods and services for human health to ensure global food security
through RA. The quantity of studies (13 out of 28) mentioning social
issues is large, however, no themes could be formed with lower levels of
L. Schreefel et al.

Global Food Security 26 (2020) 100404
5
aggregation due to a lack of studies mentioning convergent issues. This
theme, therefore, showed high variability between issues. A total
number of 27 issues was related to this theme and based on the issues we
can express that RA aims for sustainable food production which should
be in balance with both environmental and social issues. The reviewed
articles highlight the quality of human life emphasizing the need to
invest in ‘regenerating the social system’ (Dahlberg, 1994, P.173),
‘restoring human health’ (Shelef et al., 2017, P.2), ‘interspecies equity’
(Dahlberg, 1994, P.173), ‘social justice’ (Dahlberg, 1994, P.173),
‘regenerating farm families’ (Dahlberg, 1991, P.2), ‘supporting local
populations’ (Teague, 2017, P.348), ‘sustainable food supply’ (Francis
et al., 1986, P.68) and ‘reducing food shortages’ (Rhodes, 2012, P.345).
Other issues mentioned were tting social costs (Dahlberg, 1994, P.174),
‘improvements in animal welfare’ (Colleya et al., 2019, P.3), ‘cultural
re-appreciation’ (van den Berg et al., 2018, P.314) and ‘social diversity,
with a variety of knowledge and diverse economies’ (Zazo-Moratalla
et al., 2019, P.16). This theme presents different issues in which we can
discriminate human health and wellbeing issues relating to different
scales (e.g. farm families, local populations). For example, some articles
mentioned human health issues (e.g. physical conditions) and other
human wellbeing issues (e.g. happiness of the farmer). An issue which is
recognized by only one author is that RA values spirituality in their
holistic approach of farming (Dahlberg, 1994).
The theme of improve economic prosperity refers to the economic
sustainability of farmers: twelve out of 28 studies mentioned a total
number of fteen issues regarding economic prosperity. Issues among
this theme showed some divergence but lacked operationalisation.
Studies presenting economic issues mentioned that regenerative agri-
culture creates e.g. ‘long-term economic sustainability’ (Teague and
Barnes, 2017, P.83), ‘improves crop yields’ (Rhodes, 2017, P.80), ‘im-
proves soil productivity’ (Francis et al., 1986, P.68) and ‘political--
economic repositioning’ (van den Berg et al., 2018, P.315). Although
these issues present various diverging objectives, they all reect that
regenerative economics work towards a sustained farm income
providing goods and services that contribute to human well-being and
global food security. From the objectives within this theme, it remains
unclear what activities are involved to reach for example long-term
economic sustainability.
4. General discussion
This study is the rst to systematically review the background and
core themes of RA based on peer-reviewed articles. Analysis of the 28
included articles showed that there is currently no uniform scientic
denition. Instead, multiple combinations and variations of objectives
and activities together dene RA. The convergence within these de-
nitions resulted in the core themes of RA. These core themes are
compatible with the ecosystem services described by TEEB (2010).
Themes such as enhance and improve soil health, optimize resource man-
agement, alleviate climate change and water quality and availability are
contributing to multiple provisioning and regulating ecosystem services.
These provisioning and regulating ecosystem services described by TEEB
(2010) contribute to food security and relate to the core themes of RA by
for example regulating climate, soil erosion and water purication to
provide i.e. food, feed and fuel. Themes such as improve soil physical
quality and improve nutrient cycling are aspects that come back as sup-
porting ecosystem services. The socio-economic dimension we found in
RA, improve human health and improve economic prosperity relates,
furthermore, to some components of cultural ecosystems services. From
our review we, therefore, propose a provisional denition in which RA is
dened as: an approach to farming that uses soil conservation as the entry
point to regenerate and contribute to multiple provisioning, regulating
ecosystem and supporting ecosystem services, with the objective that this will
enhance not only the environmental, but also the social and economic di-
mensions of sustainable food production. We acknowledge that RA is a
rapidly evolving farming approach in which more views and studies
could allow further renement of the proposed denition. Although for
example, Diop (1999) and LaCanne and Lundgren (2018) based their
study on farmers perception in relation to RA, we used peer-reviewed
articles including opinion, review and research articles mainly
focusing on environmental aspects of RA. These peer-reviewed articles
articulated insights of natural scientists rather than other actors such as
farmers and policy makers.
Related to this description, we will further discuss 1) the core themes
of RA, 2) the relation of RA with circular and organic agriculture to show
their convergence and 3) the next step in fostering the transition towards
RA.
i) The core themes of RA
In this study we reviewed 28 peer-reviewed articles which enabled us
to describe themes that together characterize RA. These peer-reviewed
articles mentioned in general convergent objectives related to environ-
mental themes such as resource management, water quality and avail-
ability, alleviate climate change, with a strong focus on improving soil
quality (Fig. 2). This shows that the soil is the base of RA and that RA
strongly focusses on the environmental dimension of sustainability.
Although socio-economic objectives are mentioned in reviewed articles,
the issues raised did not result in underlying themes (issues needed to be
mentioned ve times to become a theme).
The themes are, however, sensitive to the amount of convergent is-
sues appropriate to form a theme. From the sensitivity analysis, we
learnt that, had we chosen three convergent issues to form a theme, then
cultural diversity would have been underlying to the theme improve
human health. In addition, eight other themes could then have been
formed as well, which include minimize waste underlying to optimize
resource management; minimize erosion, improve water holding capacity and
improve water inltration underlying to improve soil physical quality;
intercropping, the use of windbreaks, forest farming, riparian buffers, silvo-
pasture and managed grazing in addition to minimize fertilizer and pesticide
use among activities.
ii) The relation of RA with circular and organic agriculture
In order to illustrate the convergence between sustainable farming
approaches, we relate the themes of RA to circular agriculture (CA)
which remains yet a theoretical concept and organic agriculture (OA) as
an example of a regulated farming approach.
CA originates from a much broader concept than RA, the circular
economy (CE) using the 4R-framework (reuse, repair, refurbish and
recycle) as a base-line (Fan et al., 2020; Jurgilevich et al., 2016). CA uses
the themes of industrial ecology as it promotes the circular utilization of
agricultural resources and waste products (Fan et al., 2020; Kusano
et al., 2019; Zhu et al., 2019). The entry point in CA is, therefore, to keep
ows of mass and energy of products at their highest utility through a
positive developing cycle (Blau et al., 2018; Van Zanten et al., 2018). RA
has a different entry point namely healthy soils and environmental is-
sues which should be in balance with social values (e.g. Diop, 1999).
While, RA and CA may have different entry points in their approaches,
both rely strongly on the environmental dimension of sustainability,
since they share similar objectives regarding e.g. reducing environ-
mental externalities and optimizing resource management. Neverthe-
less, RA also shows to relate to a social dimension. By contrast, it is
unclear to which extent CA also relates to this social dimension, since the
current reviewed articles about CA did not mentioned social issues
within their denitions. The different entry points of RA and CA may
lead to a different focus in their farming approach, in which CA focuses
on topics such as avoidance of waste and the reuse of resources.
Recently, this 4R framework from CE is translated to themes related to
circularity in agricultural production – referred to as circular food sys-
tems (de Boer and van Ittersum, 2018; Van Zanten et al., 2019). The
themes of circular food systems go beyond agriculture production and
L. Schreefel et al.

Global Food Security 26 (2020) 100404
6
also take into account consumption, therefore circular food systems
work on a larger scale compared to RA and also includes issues such as
reuse of by-products and feed-food competition (Van Zanten et al.,
2019).
OA is an example of a farming approach that has a comprehensively
described scientic denition and is regulated by different authorities
worldwide, e.g. European Commission (2019) and USDA (2019). The
timeline of organic agriculture is described by Arbenz et al. (2016) in
which OA started very similar to RA, with a pioneering phase (known as
Organic 1.0). In this pioneering phase objectives where used to dene
OA as a farming approach that contribute to sustainable global food
security while respecting all dimensions of sustainability. RA, as shown
in this paper, is currently in this pioneering phase and the regenerative
themes dened in this paper are to varying extents convergent with
aspects mentioned in OA as IFOAM – Organics International (2019)
focuses on the health of soils, ecosystems, people and their management
which relies on ecological processes (e.g. nutrient cycling, biodiversity).
The objectives in the pioneering phase, evolved into Organic 2.0 in
which OA was regulated by certication of standards (Arbenz et al.,
2016). These standards presented as a set of technical checklists (e.g.
USDA, 2019), described mostly what ‘not to do’, for example, ‘Do not
use synthetic pesticides’. Synthetic pesticides are replaced by ‘natural
inputs’ such as organic pesticides (zinc and copper oxide) which, how-
ever, still have a damaging effect on the environment (e.g. loss of
biodiversity) (Kuehne et al., 2017). These standards, therefore, often fail
to entirely capture the aspects that are at the core of the organic phi-
losophy (Arbenz et al., 2016) and it may be that some organic farmers
are ‘locked’ into organic regulations to guarantee the delivery of prod-
ucts that conform to organic standards. The Organic 3.0 strategy rec-
ognizes this and aims to change this by becoming less prescriptive and
more descriptive, working towards the replacement of the list of ‘do’s
and don’ts’, with a mode of outcome-based regulations which should
continuously be adaptable to local contexts (Arbenz et al., 2016). This
requires a systemic shift towards an integrative farming approach like
RA (LaCanne and Lundgren, 2018). Such an integrative farming
approach does not focus on individual (pre-decided) sustainable activ-
ities, but on improving ecological and social processes and observable
outcomes which enable a larger solution space for implementing sus-
tainable activities. Some authors, therefore, mention that regenerative
activities are organic, however, other reviewed articles showed that not
all organic activities are regenerative (e.g. Pearson, 2007; Rhodes, 2017)
for example the use of organic pesticides and raw minerals. Not all ob-
jectives of OA however are centre-stage in RA, with one difference being
the objective to promote animal welfare (European Commission,
2019b). Improvement of animal welfare is mentioned in one
peer-reviewed article dening RA, although certication frameworks for
RA such as Regenerative Organic Certication do put animal welfare
centre-stage. As RA is currently in the pioneering phase, there is merit in
building on the learnings from the evaluation of OA through the last
hundred years, to avoid and leapfrog similar pitfalls that may arise.
iii) The next step in fostering the transition towards RA
This review showed the core themes of RA from the many denitions
that are presented in peer-reviewed articles. These core themes of RA,
enable to dene indicators to allow actors to regulate and control their
activities to foster the transition towards RA. The reviewed articles do
show indicators on some specic practices of RA, for example, Elevitch
et al. (2018) provide regenerative agroforestry standards. They present a
measure which should increase biodiversity throughout the life of the
agroforest: at least eight plant families, genera, species, and/or varieties
of woody perennials per 100 m
2
. It is, however, unclear if this measure
refers to each category (e.g. families, genera, species) individually or
whether it refers to the sum of the individual categories. Furthermore,
the applicability of these standards to other farming practices is limited.
Based on the current reviewed articles we were therefore unable to
identify specic indicators which allow for a generic assessment of RA.
Other research, however, shows a wide range of indicators are already
available for sustainability assessments (De Olde et al., 2016) which can
be related to each of the themes underpinning RA. Having derived a
clear provisional denition, our next step is to link these indicators to
the themes of RA described in this paper, in order to facilitate a
comprehensive assessment of RA and potentially rene the denition.
5. Conclusion
This review has systematically assessed denitions of RA in 28 peer-
reviewed articles. Our analysis has shown that such denitions are based
on several combinations and variations of recurring objectives and ac-
tivities from scientists. The convergence within these denitions
allowed us to formulate core themes of RA. Our ndings show that RA
focuses strongly on the environmental dimension of sustainability,
which includes themes such as enhance and improve soil health, optimize
resource management, alleviate climate change, improve nutrient cycling and
water quality and availability, articulated by both objectives (e.g. improve
soil quality) and activities (e.g. use perennials). These themes enhance
food security by contributing to provisioning (e.g. food, feed and bre),
regulating (e.g. climate regulation, soil erosion and water purication)
and supporting (e.g. nutrient cycling and soil formation) ecosystem
services. We also found a socio-economic dimension in RA, improve
human health and improve economic prosperity, which relate to aspects of
cultural ecosystem services. This socio-economic dimension, however,
relies currently on divergent objectives and lacks a framework for-
implementation. Therefore, we propose a provisional denition which
denes RA as an approach to farming that uses soil conservation as the
entry point to regenerate and contribute to multiple provisioning,
regulating and supporting services, with the objective that this will
enhance not only the environmental, but also the social and economic
dimensions of sustainable food production. To foster the transition to-
wards RA, this review contributes to establishing a uniform denition;
subsequently, indicators and benchmarks should be created to assess
RA.
Declaration of competing interest
The authors declare that they have no known competing nancial
interests or personal relationships that could have appeared to inuence
the work reported in this paper.
Acknowledgements
The work presented in this paper is part of TiFN’s Regenerative
Farming project, a public - private partnership on precompetitive
research in food and nutrition. The authors have declared that no
competing interests exist in the writing of this publication. Funding for
this research was obtained from FrieslandCampina, Cosun, BO Akker-
bouw, TKI Agri & Food and TiFN.
Appendix A. Supplementary data
Supplementary data to this article can be found online at https://doi.
org/10.1016/j.gfs.2020.100404.
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