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Soil Fertility and Biodiversity in Organic Farming Science

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An understanding of agroecosystems is key to determining effective farming systems. Here we report results from a 21-year study of agronomic and ecological performance of biodynamic, bioorganic, and conventional farming systems in Central Europe. We found crop yields to be 20% lower in the organic systems, although input of fertilizer and energy was reduced by 34 to 53% and pesticide input by 97%. Enhanced soil fertility and higher biodiversity found in organic plots may render these systems less dependent on external inputs.
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DOI: 10.1126/science.1071148
, 1694 (2002); 296Science
et al.Paul Maeder,
Soil Fertility and Biodiversity in Organic Farming
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already weakened by overfishing (18). Possi-
ble mechanisms by which such changes may
be manifest are reviewed by Sundby (19).
Because changes in community structure re-
flect the adjustment of pelagic ecosystems to
modifications in water masses, currents, and/
or atmospheric forcing, it is clearly important
to continue to monitor plankton associations,
which provide us with a valuable means of
checking the well-being of marine ecosys-
tems in the North Atlantic Ocean and possi-
bly in other oceanic regions.
References and Notes
1. D. Roemmich, J. McGowan, Science 267, 1324 (1995).
2. S. Levitus et al., Science 292, 267 (2001).
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Ecol. Prog. Ser., in press.
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(1994).
8. Supporting material is available on Science Online.
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Ecol. Prog. Ser. 204, 299 (2000).
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Ser. 219, 189 (2001).
11. C. Parmesan et al., Nature 399, 579 (1999).
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14. J. W. Hurrell, H. Van Loon, Clim. Change 36, 301
(1997).
15. R. R. Dickson, W. R. Turrell, in The Ocean Life of
Atlantic Salmon. Environmental and Biological Factors
Influencing Survival, D. Mills, Ed. (Fishing News Books,
Bodmin, UK, 2000), pp. 92–115.
16. J. C. Quero, M. H. Du Buit, J. J. Vayne, Oceanol. Acta
21, 345 (1998).
17. P. C. Reid, N. P. Holliday, T. J. Smyth, Mar. Ecol. Prog.
Ser. 215, 283 (2001).
18. C. M. O’Brien, C. J. Fox, B. Planque, J. Casey, Nature
404, 142 (2000).
19. S. Sundby, Sarsia 85, 277 (2000).
20. B. J. Pyper, R. M. Peterman, Can. J. Fish. Aquat. Sci.
55, 2127 (1998).
21. We are grateful to the staff of the Sir Alister Hardy
Foundation for Ocean Science and the shipping compa-
nies, captains, and crew whose sustained support has
allowed the long-term maintenance of the Continuous
Plankton Recorder (CPR) data set. The main support for
this work was from the United Kingdom, the Nether-
lands, the Atlantic Salmon Trust, the French PNEC Art 4
Programme, and the EU MAST-III programme. Consor-
tium support for the CPR survey is provided by agencies
from the following countries: Canada, the Faeroes,
France, Iceland, the Intergovernmental Oceanographic
Commission, Ireland, the Netherlands, Portugal, the
United Kingdom, and the United States.
Supporting Online Material
www.sciencemag.org/cgi/content/full/296/5573/1692/
DC1
Materials and Methods
Figs. S1 to S4
References
27 February 2002; accepted 25 April 2002
Soil Fertility and Biodiversity in
Organic Farming
Paul Ma¨der,
1
* Andreas Fliebach,
1
David Dubois,
2
Lucie Gunst,
2
Padruot Fried,
2
Urs Niggli
1
An understanding of agroecosystems is key to determining effective farming
systems. Here we report results from a 21-year study of agronomic and eco-
logical performance of biodynamic, bioorganic, and conventional farming sys-
tems in Central Europe. We found crop yields to be 20% lower in the organic
systems, although input of fertilizer and energy was reduced by 34 to 53% and
pesticide input by 97%. Enhanced soil fertility and higher biodiversity found in
organic plots may render these systems less dependent on external inputs.
Intensive agriculture has increased crop
yields but also posed severe environmental
problems (1). Sustainable agriculture would
ideally produce good crop yields with mini-
mal impact on ecological factors such as soil
fertility (2, 3). A fertile soil provides essential
nutrients for crop plant growth, supports a
diverse and active biotic community, exhibits
a typical soil structure, and allows for an
undisturbed decomposition.
Organic farming systems are one alterna-
tive to conventional agriculture. In some Eu-
ropean countries up to 8% of the agricultural
area is managed organically according to Eu-
ropean Union Regulation (EEC) No. 2092/91
(4). But how sustainable is this production
method really? The limited number of long-
term trials show some benefits for the envi-
ronment (5, 6 ). Here, we present results from
1
Research Institute of Organic Agriculture, Acker-
strasse, CH-5070 Frick, Switzerland.
2
Swiss Federal
Research Station for Agroecology and Agriculture,
Reckenholzstrasse 191, CH-8046 Zu¨rich, Switzerland.
*To whom correspondence should be addressed. E-
mail: paul.maeder@fibl.ch
Fig. 2. Principal component analysis of long-
term changes in SST in the North Atlantic
Ocean. (A) First eigenvector and principal com-
ponent (PC) (in black). Long-term changes in
NHT anomalies (in red) and the Pearson corre-
lation coefficient between the first PC and NHT
anomalies are indicated. (B) Second eigenvec-
tor and PC (in black). The long-term changes in
the winter NAO (in red) and the Pearson cor-
relation coefficient between the second PC and
the NAO index are indicated. The signal dis-
played by the first PC is highly correlated pos-
itively with NHT anomalies [Pearson correla-
tion coefficient (r
P
) 0.67, P 0.001]. In the
Subarctic Gyre, the values of the second PC
decreased until about 1993 and then increased.
The long-term change in the second PC is high-
ly correlated negatively with the NAO index
(r
p
0.63, P 0.001). Probability was cor-
rected to account for temporal autocorrelation
with the method recommended by Pyper et al.
(20).
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the 21-year “DOK” system comparison trial
(bio-Dynamic, bio-Organic, and “Konventio-
nell”), which is based on a ley rotation. The
field experiment was set up in 1978 on a loess
soil at Therwil, Switzerland [(7) and support-
ing online material). Two organic farming
systems (biodynamic, BIODYN; bioorganic,
BIOORG) and two conventional systems (us-
ing mineral fertilizer plus farmyard manure:
CONFYM; using mineral fertilizer exclusive-
ly: CONMIN) are emulated in a replicated
field plot experiment (table S1 and fig. S1).
Both conventional systems were modified to
integrated farming in 1985. Crop rotation,
varieties, and tillage were identical in all
systems (table S2).
We found nutrient input (N, P, K) in the
organic systems to be 34 to 51% lower than
in the conventional systems, whereas mean
crop yield was only 20% lower over a period
of 21 years (Fig. 1, Table 1), indicating an
efficient production. In the organic systems,
the energy to produce a crop dry matter unit
was 20 to 56% lower than in conventional
and correspondingly 36 to 53% lower per unit
of land area (tables S4 and S5).
Potato yields in the organic systems were
58 to 66% of those in the conventional plots
(Fig. 1), mainly due to low potassium supply
and the incidence of Phytophtora infestans.
Winter wheat yields in the third crop rotation
period reached an average of 4.1 metric tons
per hectare in the organic systems. This cor-
responds to 90% of the grain harvest of the
conventional systems, which is similar to
yields of conventional farms in the region (8).
Differences in grass-clover yields were small.
Cereal crop yields under organic manage-
ment in Europe typically are 60 to 70% of
those under conventional management,
whereas grassland yields are in the range of
70 to 100%. Profits of organic farms in Eu-
rope are similar to those of comparable con-
ventional farms (9). Appropriate plant breed-
ing may further improve cereal yields in or-
ganic farming. There were minor differences
between the farming systems in food quality
(10).
The maintenance of soil fertility is im-
portant for sustainable land use. In our
experimental plots, organically managed
soils exhibit greater biological activity than
the conventionally managed soils. In con-
trast, soil chemical and physical parameters
show fewer differences (Fig. 2).
Soil aggregate stability as assessed by the
percolation method (11) and the wet sieving
method (12) was 10 to 60% higher in the
organic plots than in the conventional plots
(Fig. 2A). These differences reflect the situ-
ation as observed in the field (Fig. 3, A and
B), where organic plots had a greater soil
stability. We found a positive correlation be-
tween aggregate stability and microbial bio-
mass (r 0.68, P 0.05), and between
aggregate stability and earthworm biomass
(r 0.45, P 0.05).
Soil pH was slightly higher in the organic
systems (Fig. 2B). Soluble fractions of phos-
phorus and potassium were lower in the or-
ganic soils than in the conventional soils,
whereas calcium and magnesium were high-
er. However, the flux of phosphorus between
the matrix and the soil solution was highest in
the BIODYN system (13). Soil microorgan-
isms govern the numerous nutrient cycling
reactions in soils. Soil microbial biomass in-
creased in the order CONMIN CON-
FYM BIOORG BIODYN (Fig. 2C). In
soils of the organic systems, dehydrogenase,
protease, and phosphatase activities were
higher than in the conventional systems, in-
dicating a higher overall microbial activity
and a higher capacity to cleave protein and
organic phosphorus (12). Phosphorus flux
through the microbial biomass was faster in
organic soils, and more phosphorus was
bound in the microbial biomass (14, 15).
Evidently, nutrients in the organic systems
are less dissolved in the soil solution, and
microbial transformation processes may
contribute to the plants’ phosphorus supply.
Fig. 1. Yield of winter wheat,
potatoes, and grass-clover in the
farming systems of the DOK tri-
al. Values are means of six years
for winter wheat and grass-clo-
ver and three years for potatoes
per crop rotation period. Bars
represent least significant differ-
ences (P 0.05).
Table 1. Input of nutrients, pesticides, and fossil energy to the DOK trial systems.
Nutrient input is the average of 1978–1998 for BIODYN, BIOORG, and CONFYM
and 1985–1998 for CONMIN. Soluble nitrogen is the sum of NH
4
-N and NO
3
-N.
The input of active ingredients of pesticides was calculated for 1985–1991.
Energy for production of machinery and infrastructure, in fuel, and for the
production of mineral fertilizer and pesticides has been calculated for 1985–1991.
Farming
system
Total nitrogen
(kgNha
1
year
1
)
Soluble nitrogen
(kgNha
1
year
1
)
Phosphorus
(kgPha
1
year
1
)
Potassium
(kgKha
1
year
1
)
Pesticides (kg active
ingredients ha
1
year
1
)
Energy
(GJ ha
1
year
1
)
BIODYN 99 34 24 158 0 12.8
BIOORG 93 31 28 131 0.21 13.3
CONFYM 149 96 43 268 6 20.9
CONMIN 125 125 42 253 6 24.1
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Mycorrhizae as members of the soil com-
munity ameliorate plant mineral nutrition and
contribute to soil aggregate formation (16 ).
Root length colonized by mycorrhizae in or-
ganic farming systems was 40% higher than
in conventional systems (7) (Fig. 2C).
Biomass and abundance of earthworms
were higher by a factor of 1.3 to 3.2 in the
organic plots as compared with conventional
(17) (Fig. 2D). We also investigated epigaeic
arthropods that live above ground, because
they are important predators and considered
sensitive indicators of soil fertility. Average
activity density of carabids, staphylinids, and
spiders in the organic plots was almost twice
that of the conventional plots (18) (Fig. 2D).
Healthy ecosystems are characterized by
high species diversity. The DOK trial shows
that organic farming allows the development of
a relatively diverse weed flora. Nine to 11 weed
species were found in organically managed
wheat plots and one species in conventional
plots. Between 28 and 34 carabid species were
found in the BIODYN system, 26 to 29 species
in the BIOORG system, and 22 to 26 species in
the CONFYM system (18). Some specialized
and endangered species were present only in
the two organic systems. Apart from the pres-
ence and diversity of weeds, direct effects of
pesticides and the density of the wheat crop
stand are most likely influencing arthropod ac-
tivity and diversity.
One of the particularly remarkable find-
ings, presented in Fig. 4, was a strong and
significant increase in microbial diversity
(BIOLOG Inc., Hayward, CA) in the order
CONMIN, CONFYM BIOORG BIO-
DYN, and an associated decrease in the met-
abolic quotient (qCO
2
)(19). According to
Odum’s theory on the strategy of ecosystem
development, the ratio of total respiration to
total biomass decreases during succession in
an ecosystem (20). This quotient has been
adapted to soil organisms (21), where CO
2
evolution is a biological process mainly gov-
erned by microorganisms. The lower qCO
2
in
the organic systems, especially in the BIO-
DYN system, indicates that these communi-
ties are able to use organic substances more
for growth than for maintenance.
Under controlled conditions, the diverse
microbial community of the BIODYN soil
decomposed more
14
C-labeled plant material
than the ones of the conventional soils (22).
In the field, light fraction particulate organic
matter, indicating undecomposed plant mate-
rial, decayed more completely in organic sys-
tems (23). Hence, microbial communities
Fig. 2. Physical, chemical, and biological soil
properties in soils of the DOK farming systems.
Analyses were done within the plough horizon
(0 to 20 cm) except for soil fauna. Results are
presented relative to CONFYM ( 100%) in
four radial graphs. Absolute values for 100% are
as follows. (A) Percolation stability, 43.3 ml
min
1
; aggregate stability, 55% stable aggre-
gates 250 m; bulk density, 1.23 g cm
3
.(B)
pH(H
2
O), 6.0; organic carbon, 15.8 g C
org
kg
1
;
phosphorus, 21.4 mg P kg
1
; potassium, 97.5
mgKkg
1
; calcium, 1.7 g Ca kg
1
; magnesium,
125 mg Mg kg
1
.(C) Microbial biomass, 285 mg
C
mic
kg
1
; dehydrogenase activity, 133 mg TPF
kg
1
h
1
; protease activity, 238 mg tyrosine
kg
1
h
1
; alkaline phosphatase, 33 mg phenol
kg
1
h
1
; saccharase, 526 mg reduced sugar
kg
1
h
1
; mycorrhiza, 13.4% root length colo-
nized by mycorrhizal fungi. (D) Earthworm bio-
mass, 183 g m
2
; earthworm abundance, 247
individuals m
2
; carabids, 55 individuals;
staphylinids, 23 individuals; spiders, 33 individ-
uals. Arthropods have not been determined in
the CONMIN system because of the field trial
design. Significant effects were found for all
parameters except for bulk density, C
org
, and
potassium (analysis of variance; P 0.05). For
methods, see table S3.
Fig. 3. Biodynamic (A) and conventional (B) soil surface in winter wheat plots. Earthworm casts and
weed seedlings are more frequent in the biodynamic plot. Disaggregation of soil particles in the
conventional plots leads to a smoother soil surface. Wheat row distance is 0.167 m. Source: T.
Alfo¨ldi, Research Institute of Organic Agriculture [Forschungsinstitut fu¨r biologischen Landbau
(FiBL)].
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with an increased diversity in organic soils
transform carbon from organic debris into
biomass at lower energy costs, building up a
higher microbial biomass. Accordingly, the
functional role of diverse plant communities
in soil nitrate utilization has been quoted
(24), as well as the significance of mycorrhi-
zal diversity for phosphorus uptake and plant
productivity (25). The consistent results of
these two studies (24, 25) and our own within
the soil-plant system support the hypothesis
that a more diverse community is more effi-
cient in resource utilization. The improve-
ment of biological activity and biodiversity
below and above ground in initial stages of
food webs in the DOK trial is likely to pro-
vide a positive contribution toward the devel-
opment of higher food web levels including
birds and larger animals.
The organic systems show efficient re-
source utilization and enhanced floral and
faunal diversity, features typical of mature
systems. There is a significant correlation
(r 0.52, P 0.05) between above-ground
(unit energy per unit crop yield) and below-
ground (CO
2
evolution per unit soil microbial
biomass) system efficiency in the DOK trial.
We conclude that organically manured, le-
gume-based crop rotations utilizing organic
fertilizers from the farm itself are a realistic
alternative to conventional farming systems.
References and Notes
1. D. Pimentel et al., Science 267, 1117 (1995).
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(1999).
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396, 262 (1998).
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Hinman, Nature 410, 926 (2001).
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Niggli, Biol. Fertil. Soils 31, 150 (2000).
8. P. Simon, Landwirtschaftliches Zentrum Ebenrain,
CH-4450 Sissach/BL, personal communication.
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Organic Farms in Europe (University of Hohenheim,
Hago Druck & Medien, Karlsbad-Ittersbach, Germany,
2000), vol. 5.
10. T. Alfo¨ldi et al., unpublished observations.
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Ecosys. Environ. 69, 253 (1998).
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demic Press, London, ed. 2, 1997).
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18. L. Pfiffner, U. Niggli, Biol. Agric. Hortic. 12, 353
(1996).
19. A. Fliebach, P. Ma¨der, in Microbial Communities—
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26. We sincerely thank all co-workers in the DOK trial,
especially W. Stauffer and R. Frei and the farmer
groups. We also thank T. Boller and A. Wiemken and
two unknown referees for their helpful comments.
This work was supported by the Swiss Federal
Office for Agriculture and the Swiss National Sci-
ence Foundation.
Supporting Online Material
www.sciencemag.org/cgi/content/full/296/5573/1694/
DC1
Materials and Methods
Fig. S1
Tables S1 to S5
21 February 2002; accepted 26 April 2002
Control of Stomatal
Distribution on the Arabidopsis
Leaf Surface
Jeanette A. Nadeau and Fred D. Sack*
Stomata regulate gas exchange and are distributed across the leaf epidermis
with characteristic spacing. Arabidopsis stomata are produced by asymmetric
cell divisions. Mutations in the gene TOO MANY MOUTHS (TMM) disrupt
patterning by randomizing the plane of formative asymmetric divisions and by
permitting ectopic divisions. TMM encodes a leucine-rich repeat–containing
receptor-like protein expressed in proliferative postprotodermal cells. TMM
appears to function in a position-dependent signaling pathway that controls the
plane of patterning divisions as well as the balance between stem cell renewal
and differentiation in stomatal and epidermal development.
Stomata allow gas exchange and thus are key
to the survival of land plants, yet the genes
controlling stomatal development are poorly
understood (1, 2). Both the number and dis-
tribution of stomata are regulated during leaf
development. Stomata are formed after a se-
ries of asymmetric divisions of transiently
self-renewing precursors termed meriste-
moids [fig. S1 (3)]. Stomata are continually
produced during the mosaic development of
the leaf, and many form by division of cells
next to preexisting stomata (Fig. 1A). Correct
spacing results when the plane of formative
asymmetric divisions is oriented so that the
new precursor, the satellite meristemoid, does
not contact the preexisting stoma or precursor
(1, 4 ). Intercellular signaling provides spatial
cues that regulate division orientation and
may also block asymmetric division in cells
adjacent to two stomata or precursors (4 ).
The recessive too many mouths (tmm) muta-
tion randomizes the plane of asymmetric di-
vision in cells next to a single stoma or
precursor and permits asymmetric divisions
in cells next to two stomata or precursors,
thus producing clusters of stomata (Fig. 1, A
and C). Also, tmm meristemoids divide fewer
times before assuming the determinate guard
mother cell fate. These phenotypes suggest
that TMM is required for cells to respond
appropriately to their position during stoma-
tal development and that TMM participates in
intercellular signaling.
With the use of positional cloning (3),
TMM was found to encode a leucine-rich
repeat (LRR)–containing receptor-like pro-
tein of 496 amino acids with a molecular
weight of 54 kD (Fig. 2A). The predicted
protein product contains 10 uninterrupted
plant-type LRRs (5) and a putative COOH-
terminal transmembrane domain. TMM en-
Department of Plant Biology, Ohio State University,
1735 Neil Avenue, Columbus, OH 43210, USA.
*To whom correspondence should be addressed. E-
mail: sack.1@osu.edu
Fig. 4. Soil microbial functional diversity
(Shannon index H’) and metabolic quotient
(qCO
2
soil basal respiration/soil microbial
biomass) correlate inversely. A higher diversity
in the organic plots is related to a lower qCO
2
,
indicating greater energy efficiency of the more
diverse microbial community. The Shannon in-
dex is significantly different between both con-
ventional systems (CONFYM, CONMIN) and
the BIODYN system, the qCO
2
, between
CONMIN and BIODYN (P 0.05).
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... By avoiding synthetic inputs in form of fertilizers and pesticides, organic cropping systems produce lower yields compared to conventional systems 29,30 . Yet, organic systems show beneficial environmental effects on soil fertility and soil organic matter [31][32][33] , profitability, nutritional value, biodiversity and water quality 34 . In line with that, a recent study showed enhanced multifunctionality and provision of regulating ecosystem services in organic systems and conservation tillage, based on a short-term field experiment 35 . ...
... The present study provides a quantitative base for the long-term effect of organic and conventional cropping systems on critical ecosystem services by synthesizing more than four decades of research in the world's oldest cropping system comparison trial -the DOK experiment 31 . This experiment compares two organic (bio-dynamic: BIODYN; bio-organic: BIOORG) with two conventional cropping systems (one with farmyard manure and mineral fertilizers: CONFYM, also called as integrated system; one with mineral fertilizers alone: CONMIN) since 1978 (Table 1, Fig S1). ...
... The main challenge for organic cropping systems are lower yields due to reduced nutrient and pesticide inputs 30 . The mean yield reduction between organic (BIODYN and BIOORG) and conventional (CONFYM and CONMIN) systems after CRP3 was 20% 31 . Yet, in this study the yield reduction declined to 15% after the inclusion of maize and soya from CRP 4 onwards (Fig. 4, Fig. S5-9). ...
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Agriculture provides food to a still growing population but is a major driver of the acceleration of global nutrient flows, climate change, and biodiversity loss. Policies such as the European Farm2Fork strategy aim to mitigate the environmental impact of land-use by fostering organic farming. To assess long-term environmental impact of organic food production we synthesized more than four decades of research on agronomic and environmental performance of the oldest system comparison experiment on organic and conventional cropping systems (DOK experiment). Two organic systems (bioorganic and biodynamic) are compared with two conventional (manure-based integrated and mineral-based) systems all with the same arable crop rotation including grass-clover, and manure from livestock integrated in all except the mineral-based system. Organic systems used 92% less pesticides and 76% less mineral nitrogen than conventional systems. Nitrogen use efficiency, that also considers biological nitrogen fixation, was above 85% for all systems. Organic fertilization with farmyard manure maintained or increased soil carbon and nitrogen stocks in the long term, especially in the biodynamic system with manure compost. Conventional mineral-based cropping reduced soil organic carbon and nitrogen stocks. Higher soil organic carbon stocks in organic cropping did not translate to increased N2O emissions, which were the main driver for 56% lower soil-based, area-scaled climate impact compared to the integrated conventional system with manure. Organic cropping systems, especially compost-based biodynamic, showed enhanced soil health, richness of micro- and macrofauna and weed species. Highest yields were achieved in integrated conventional system, with highest total nitrogen inputs and enhanced soil health compared to pure mineral fertilization. Yet, these benefits come at the cost of lower nitrogen use efficiency and higher N2O emissions. Despite a rigorous reduction of inputs yields of the organic systems achieved 85% of the conventional systems. We demonstrate at field level that organic cropping systems with reduced external nutrient inputs have less climate impact and a larger in-situ biodiversity, while providing a fertile ground for the future development of sustainable agricultural production systems.
... The growth in scientific coverage of the organic sector was inevitably accompanied by a widening of the array of subjects addressed by researchers, who opened several fronts in organic research. In this respect, some examples include analyses of environmental and ecological aspects of organic agriculture [5,6], studies on alternative farming practices in organic farms [7,8], comparisons of organic and conventional productivity [9][10][11][12], and investigations into the nutritional and quality aspects of organic food [13,14]. ...
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The world organic sector has evolved in a rapid way over the last few decades, driven by consumer interest, producer and retailer strategies, as well as by the evolving normative context. This growth has stimulated an increase in academic research, particularly in socio-economic research. The present work aims to understand the evolution of organic socio-economic research in terms of the research themes covered within this field, their relative importance, and how this importance has changed over time. The implementation of a structural topic model on scientific abstracts from the last 20 years allowed us to identify three broad areas of interest for organic socio-economic researchers: consumers, production, and society. The relevance of these strands varies in different areas of the world, mostly aligning with the prominent aspects of local organic sectors. This signals a good integration of organic socio-economic research within local contexts, with the possible development of place-based skills to be exploited within the global debate on organic agriculture. Overall, a reasonably strong imbalance emerges, with consumer-focused studies being more prominent than production-focused ones, especially those investigating producers’ economic results. The latter seems to call for renewed attention on and analysis of the organic sector, assisted by robust evidence on both ends of the organic supply chain.
... According to Mäder et al. (2002), their use may accelerate the breakdown of organic matter and perhaps lessen aggregate stability. Therefore, keeping soil quality is an essential requirement for sustainable agriculture (Asghar et al., 2022).The search for higher yields, lower production costs, and increased sustainability in agriculture implies optimizing crop nutritional management (Conceicao et al., 2022). ...
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... Practices and key experiences for ecological redesign and modernized crop protection and production can be drawn from farming practices that employ restricted or actively minimized pesticide use, such as organic and agroecological farming (Mäder et al. 2002;Wezel et al. 2014;van Bruggen et al. 2016). These practices are increasingly evidenced and implemented widely enough to inspire innovation and create a testing ground for adoption. ...
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... In 1978 the DOK Trial was launched (acronym for Biodynamic (D), Organic (O), conventional or Konventionell (K) in German language), a long-term research project which is still in place today, comparing the results of conventional, organic and biodynamic agriculture. The results of the DOK Trial in the 1980s brought a first academic scientific recognition for BF and provided reassurance to farmers of its value (Mäder et al. 2002). In 1997, Demeter International was created with the aim of federating the national associations, and common international specifications and certification were formalized. ...
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In the context of the agroecological transition, the ability of alternative ways of farming to develop themselves in the long run without being co-opted by mainstream input intensive agriculture is essential. Biodynamic farming (BF), which began a century ago in 1924, was one of the first alternatives to modern agriculture, associated with specific agricultural practices, worldview and human-nature relationships. Over the last 100 years, BF has developed worldwide in a context of growing industrialization, without becoming industrialized itself, and it is still considered today as a radically alternative way of farming. To better understand the resistance of BF, this paper provides an overview of its history, with particular emphasis on its complex relationships with the broader organic agriculture (OA) movement. Three overlapping historical stages are distinguished: (1) Agronomic consolidation stage: from Rudolf Steiner’s agricultural courses to the first “Agricultural Experimental Circle”, the creation of the Demeter label and the emergence of OA (first half of 20th century); (2) Institutionalization stage; Initially, BF was coevolving closely with the growing OA movement, but then the differentiation between both progressively increased. Meanwhile the first collaborations with academic research institutes were initiated; (3) Expansion stage: With growing commercialization opportunities for biodynamic products, the 21st century corresponds to a stage of economic development for BF and a new wave of geographic expansion in every continent. In the final section of the paper, the implications for sustainability transformations are discussed. Particularly, it is argued that the ability of BF to combine strategies of agronomic consolidation, institutionalization and expansion over time could be the key to its resilience. The complementarities between BF and other alternative ways of farming might play an important role in future evolutions.
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Sustainable agriculture development through organic farming not only provides food requirements for the current creation in an environmentally friendly way manner also however provides food for prospective generations and controls our surroundings. Mainly, quality food is provided by organic farming without negative effects on the condition and effectiveness of the soil side by side with the environment. Organic farming also helps to produce a larger quantity of food for a huge amount of the Indian population. In current agriculture huge number of pesticides, fertilizers and synthetic compounds are used, which causes adverse impacts on soil health, water hazards, toxic residues increasing in the animal feed industry and the food chain in this manner increasing healthcare issues. The objective of the review paper is to identify synthetic fertilizers and pesticides that can be replaced with natural alternatives as well as to examine how organic farming might promote sustainability in agriculture.
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The effects of conventional and biological farming systems on soil P dynamics were studied by measuring some microbiological parameters after 13 years of different cropping systems. The treatments included control, biodynamic, bio-organic, and conventional plots and a mineral fertilizer treatment. The farming systems differed mainly in the form and quantity of nutrients applied and in the plant protection strategies. The results of a sequential fractionation procedure showed that irrespective of the form of P applied, neither 0.5 M NaHCO inf3 sup- nor 0.1 M NaOH-extractable organic P, but only the inorganic fractions, were affected. The residual organic P, not extracted by NaHCO3 or NaOH was increased in the biodynamic and bio-organic plots. The soil microbial biomass (ATP content) and the activity of acid phosphatase were also higher in both biologically managed systems. These results were attributed to the higher quantity of organic C and organic P applied in these systems, but also to the absence of or severe reduction in chemical plant protection. The relationship between acid soil phosphatase and residual organic P was interpreted as an indication that this fraction might be involved in short-term transformations. The measurement of the intensity, quantity, and capacity factors of available soil P using the 32P isotopic exchange kinetic method showed that P could not be the factor limiting crop yield in the biological farming systems. The kinetic parameters describing the ability of P ions to leave the soil solid phase, deduced from isotopic exchange, were significantly higher for the biodynamic treatment than for all other treatments. This result, showing a modification of chemical bonds between P ions and the soil matrix, was explained by the higher Ca and organic matter contents in this system.