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Sustainable Agriculture: A Case Study of a Small Lopez Island Farm

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Sustainable Agriculture: A Case Study of a Small Lopez Island Farm

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Overreliance on fossil fuel based inputs, and transport of inputs and products is seen by many as a threat to long-term agricultural and food system sustainability. Many organic, biodynamic, and low-input farmers limit off-farm inputs, attempting instead to farm within the carrying capacity of their land or local environment. These farmers often accept lower farm productivity because they see reduced reliance on non-renewable inputs as more sustainable. Documentation of low-input agricultural systems through both replicated research trials and case studies is needed in order to better understand perceived and real advantages and tradeoffs. The goal of our study was twofold: (1) to compare liming and biodynamic (BD) preparations in improving pasture on a moderately acidic pasture soil through stimulation of soil microbial activity; (2) to place these findings within the context of a whole farm analysis of economic, plant, and animal health. Treatments included lime, the Pfeiffer Field Spray plus BD compost preparations, and untreated controls. Soil pH, total C and N, microbial activity, forage biomass, and forage quality were evaluated over two growing seasons. Both lime and the Pfeiffer Field Spray and BD preparations were only moderately effective in raising soil pH, with no effect on soil microbial activity or forage yield. Lime significantly reduced forage crude protein but the practical implications of this are questionable given the overall low quality of the forage. While the farm is profitable and economically stable and the animals healthy, the need for future targeted nutrient inputs cannot be ruled out for sustainable long-term production.
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Sustainable agriculture: A case study of a small Lopez Island farm
J.R. Reeve
a,
, L. Carpenter-Boggs
b
, H. Sehmsdorf
c
a
Dept. Plants, Soils, and Climate, Utah State University, Logan, UT 83422-4820, USA
b
Dept. Crop & Soil Sciences, Washington State University, Pullman, WA 99164-6420, USA
c
S&S Center for Sustainable Agriculture and Homestead Farm, Lopez Island, WA 98261, USA
article info
Article history:
Received 29 June 2010
Received in revised form 20 April 2011
Accepted 22 April 2011
Available online 12 June 2011
Keywords:
Soil pH
Forage quality
Biodynamic preparations
Sustainable pasture management
abstract
Overreliance on fossil fuel based inputs, and transport of inputs and products is seen by many as a threat
to long-term agricultural and food system sustainability. Many organic, biodynamic, and low-input farm-
ers limit off-farm inputs, attempting instead to farm within the carrying capacity of their land or local
environment. These farmers often accept lower farm productivity because they see reduced reliance
on non-renewable inputs as more sustainable. Documentation of low-input agricultural systems through
both replicated research trials and case studies is needed in order to better understand perceived and real
advantages and tradeoffs. The goal of our study was twofold: (1) to compare liming and biodynamic (BD)
preparations in improving pasture on a moderately acidic pasture soil through stimulation of soil micro-
bial activity; (2) to place these findings within the context of a whole farm analysis of economic, plant,
and animal health. Treatments included lime, the Pfeiffer Field Spray plus BD compost preparations,
and untreated controls. Soil pH, total C and N, microbial activity, forage biomass, and forage quality were
evaluated over two growing seasons. Both lime and the Pfeiffer Field Spray and BD preparations were
only moderately effective in raising soil pH, with no effect on soil microbial activity or forage yield. Lime
significantly reduced forage crude protein but the practical implications of this are questionable given the
overall low quality of the forage. While the farm is profitable and economically stable and the animals
healthy, the need for future targeted nutrient inputs cannot be ruled out for sustainable long-term
production.
Ó2011 Elsevier Ltd. All rights reserved.
1. Introduction
Many organic, biodynamic, low-input, and geographically iso-
lated farmers limit or entirely eliminate purchase of off-farm in-
puts, attempting instead to farm within the carrying capacity of
their land or local environment. Wastes are recycled, transporta-
tion costs to and from the farm, external inputs, and reliance on
fossil fuels are all reduced. Animals and plants are managed to
be more adapted to their local environment through cross breeding
and open pollination. Food is sold to the local community and fer-
tility is sourced within that same local community. Rotational
grazing of animals and diverse crop rotations keep nutrients cy-
cling on-farm and increase nutrient use efficiencies so that exter-
nal inputs can be reduced to a bare minimum or eliminated
altogether. Fertility, it is postulated, then becomes an emergent
property of the way the farming system is designed and operated.
This approach has been described by Edens and Haynes (1982)
among others as closed system agriculture.
These farmers often accept lower farm productivity in exchange
for what is seen as improved sustainability and reduced reliance on
expensive and ultimately non-renewable inputs. The potential
danger in such an approach is that internally generated fertility
is not sufficient to adequately offset the export of nutrients
through off farm sales. However, learning to optimize a locally
based system may be the better choice when faced with the alter-
native of expensive and non-renewable inputs.
The call to reduce reliance on non-renewable and increasingly
expensive agricultural inputs has been voiced by many over the
past decades (Edens and Haynes, 1982; Hahlbrock, 2009). With ris-
ing world populations, this presents a dilemma: how can we pro-
duce sufficient food to feed this rapidly growing population
while at the same time conserving biodiversity and developing
food production systems that are less heavily reliant on resources
that will ultimately be depleted. One approach is to increase the
efficiency with which land and resources are utilized. On the other
hand, there is growing evidence that increased agricultural effi-
ciencies, while increasing yield per unit land, do not necessarily
lead to greater resource conservation. In fact, increased efficiency
can stimulate ever greater resource use as prices of inputs drop.
In developing countries land fragmentation and deforestation
actually increase as rural populations displaced by agricultural
0308-521X/$ - see front matter Ó2011 Elsevier Ltd. All rights reserved.
doi:10.1016/j.agsy.2011.04.006
Corresponding author. Address: Department of Plants Soils and Climate, 4820
Old Main Hill AGS 332, Logan, UT 84342-4820, USA. Tel.: +1 435 797 3192; fax: +1
435 797 3376.
E-mail address: jennifer.reeve@usu.edu (J.R. Reeve).
Agricultural Systems 104 (2011) 572–579
Contents lists available at ScienceDirect
Agricultural Systems
journal homepage: www.elsevier.com/locate/agsy
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intensification move to more marginal lands (Perfecto et al., 2009).
This fact is often missed in traditional assessments of agricultural
productivity due to the failure to adequately address social, eco-
nomic, and political realities. Clearly, a thorough assessment of
the whole system, or life-cycle analysis (Heller and Keoleian,
2000), is needed when addressing these questions.
Lopez Island, WA is a small island community of 3000 people, in
the Puget Sound, a 50-min ferry ride from the mainland United
States. Until recently, the majority of the food and fiber consumed
on the island was imported at high cost, via the Washington State
ferry service. In recent years, the number of small farms has risen
significantly, and many of these farms raise grass-fed livestock,
fruit and vegetables for local consumption. Although not all are
certified as such, many of these farms are organic or biodynamic,
in that synthetic inputs are restricted and the majority of fertilizers
and animal feeds are produced on the farm.
The soils on Lopez Island tend to be shallow and low in pH due
to evergreen forest native vegetation and poor drainage. These less
than ideal soil conditions can make adequate forage production
difficult without relying on significant external inputs. Typically
farmers apply lime to ameliorate soil pH. However, the cost of lime
is high on Lopez Island due to shipping charges from the mainland,
so many farms do not apply any lime at all. In addition to standard
organic practices, BD farmers make use of specially fermented
plant and animal-based products that are applied as field sprays
and compost starters (Table 1). These preparations are used in very
small quantities which has made them a controversial aspect of the
BD approach (Carpenter-Boggs et al., 2000a; Reeve et al., 2005).
The claim is not that they act as nutrient sources, but as microbial
stimulants which in turn lead to greater available plant nutrients,
thereby helping to offset the need for external inputs. Newer for-
mulations of the BD preparations such as the Pfeiffer Field Spray
(PFS) also include the specific addition of microorganisms known
for their plant growth promoting properties (Hugh Courtney, Jose-
phine Porter Institute for applied Biodynamics personal communi-
cation). The activity of soil organisms is an integral component of
soil formation processes, including the chemical weathering of
parent material and nutrient cycling (Brady and Weil, 2002a).
The potential of microbial stimulants to raise soil pH as a cost-
effective substitute for lime therefor warrants investigation.
Peer reviewed evaluations of the efficacy of the BD preparations
are few, however, particularly in forage systems. Colmenares and
Miguel (1999) found that the preparations, sprayed on permanent
grassland over 3.5 years, increased dry matter content in the ab-
sence of any fertilization. Some evidence suggests the BD prepara-
tions influence soil microbial processes and carbon and nitrogen
dynamics (Abele, 1987; Raupp, 2001; Mäder et al., 2002; Reeve
et al., 2005) and root growth (Goldstein, 1986; Goldstein and Koe-
pf, 1992). On the other hand, other studies have proved inconclu-
sive (Pettersson et al., 1992; Penfold et al., 1995; Carpenter-
Boggs et al., 2000a, 2000b). There is no published research on
PFS, or comparison of BD preparations to lime treatment. More-
over, many researchers have expressed concern that BD and other
low-input organic and conventional systems may not be ade-
quately replacing nutrients lost through export of agricultural
goods (Penfold et al., 1995; Burkitt et al., 2007a).
The goal of the study was to first evaluate the effects of BD prep-
arations and lime on forage yield and quality. Secondly, S&S Home-
stead Farm soil nutrients, animal health, and economic stability
were surveyed in order to place our findings within the context
of whole farm health, environmental, economic, and social
sustainability.
2. Materials and methods
2.1. Site history and plot layout
The trial was located on S&S Homestead Farm on Lopez Island
WA, a 20 ha diversified smallholding raising animals, vegetables
and forages for on-farm use and local markets (www.sshome-
stead.org). While not certified, the farm has been managed organ-
ically for over 38 years. The climate on the island is temperate
maritime with average highs of 21 °C and lows of 1 °C with a mean
annual precipitation of 741 mm, the majority of which falls be-
tween November and February. No additional irrigation is supplied
to the pasture. Experimental plots 3.7 m by 61 m were laid out in a
permanent pasture in the fall of 2003 and baseline soil samples ta-
ken. Pasture species composition was approximately 35% legumes,
55% grasses and 10% broadleaf forbs (Table 2). The soil type is a
Bow Gravelly Silt Loam, 0–3% slopes, which had received no inputs
Table 1
The main ingredients and recommended (unit) amounts of the biodynamic prepa-
rations used per 0.4 ha of land or in 14 t compost.
Preparation Main Ingredient Use Unit
volume
(cm
3
)
Unit
mass
(g)
500 Cow (Bos taurus) manure Field
spray
35 38
501 Finely ground quartz silica Field
spray
2 1.8
502 Yarrow blossoms (Achilliea
millefoilium L.)
Compost 15 1.1
503 Chamomile blossoms
(Matricaria recutita L.)
Compost 15 3.0
504 Stinging nettle shoots
(Urtica dioica L.)
Compost 15 4.4
505 Oak bark (Quercus robur L.) Compost 15 3.9
506 Dandelion flowers
(Taraxacum officinale L.)
Compost 15 4.7
507 Valerian flower extract
(Valeriana officinalis L.)
Compost 2 1.2
Pfeiffer
Field
Spray
Preparations 500–507 plus
cultured bacteria
Field
spray
78 57
Table 2
Forage composition of the study site.
Legumes 35% of total
Red clover Trifolium pretense L.
White clover Trifolium repens L.
Common vetch Vicia sativa L.
Subterranean clover Trifolium subterraneum L.
Birdsfoot trefoil Lotus corniculatus L.
Grasses 55% of total
Tall fescue Schedonorus phoenix (Scop.) Holub
Meadow foxtail Alopecurus pratensis L.
Orchard grass Dactylis glomerata L.
Quackgrass Elymus repens (L.) Gould
Reed canary grass Phalaris arundinacea L.
Smooth brome Bromus inermis Leyss.
Annual ryegrass Lolium perenne L. ssp. multiflorum (Lam.) Husnot
Perennial ryegrass Lolium perenne L.
Bent grass Agrostis, sp.L.
Sedge Carex sp. L.
Rush Juncus sp.L.
Forbes 10%
Dandelion Taraxacum officinale F.H. Wigg.
Coltsfoot Tussilago farfara L.
English daisy Bellis perennis L.
Oxeye daisy Leucanthemum vulgare Lam.
Comfrey Symphytum sp. L.
Dock/sorrel Rumex sp. L.
Plantain Plantago major L.
Mustard Brassica sp. L.
Yarrow Achillea millefolium L.
J.R. Reeve et al. / Agricultural Systems 104 (2011) 572–579 573
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other than pastured animal urine and manure in over 38 years. The
site was subject to seasonal poor drainage due to the presence of a
heavy clay layer 20–30 cm below the soil surface. Treatments of
lime, BD preparations, and an untreated control were applied in
a completely randomized design with four replicates. Lime, com-
posed of 97% CaCO
3
, 10 mesh; 38.8% Ca, 20 mesh; and 2% MgCO
3
,
10 mesh (Imperial brand, J.A. Jack & Sons. Inc., Seattle WA) was ap-
plied in a single application in the fall of 2004 at a rate of
2.24 Mg ha
1
. Liming rate was calculated based on initial soil pH
of 5.5. Biodynamic treatment consisted of 1 unit of PFS together
with 1 unit of BD 502–507 applied in the fall of 2003 and 2004,
and 1 unit of 501 and Equisetum avensis applied in the spring of
2004 and 2005 (see Table 1 for unit ha
1
application rates). Pfeifer
Field Spray and BD preparations were purchased from and applied
according to directions supplied by the Josephine Porter Institute
for Applied Biodynamics (Woolwine, VA). During the field study
period 2003–2006, annual temperature was 1.0, 1.4, 1.1, and
0.8 °C warmer and precipitation was 48 mm less, 144 mm more,
46 mm more, and 61 mm more than average at the National Oce-
anic and Atmospheric Administration (NOAA) Anacortes station
12 linear miles from the farm.
2.2. Soil sampling and analysis
Soils were sampled from each plot at 0–10 cm and 10–20 cm at
the start of the trial and in May 2005 and June 2006. All samples
were a composite of 10 subsamples taken from the plot area a min-
imum 1 m from the boundary of each plot to avoid edge effects.
Samples were transported on ice to Washington State University
(WSU), Pullman, WA, passed through a 2 mm sieve, and stored at
4°C until analysis. Soil pH was measured in a 1:1 w:v deionized
water after 1 h. Soil was finely ground and total C and N measured
by combustion on a Leco CNS 2000. Readily mineralizable carbon
(Cmin), basal microbial respiration rate, and active microbial bio-
mass carbon (Cmic) by substrate-induced respiration (SIR) were
measured according to Anderson and Domsch (1978): Ten grams
soil was brought to 26% moisture content and incubated at 24 °C
for 10 days. Total CO
2
released during the 10 days was considered
Cmin. Vials were uncapped, evacuated with a stream of air passed
through water and covered with parafilm
Ò
for 22 h (to allow soil
CO
2
to equilibrate with the atmosphere without loss of soil mois-
ture), recapped for 2 h and CO
2
measured again for the basal respi-
ration rate. Samples were again uncapped, evacuated, and covered
with parafilm
Ò
for 22 h, then 0.5 mL of a 30 g L
1
aqueous solution
of glucose was added to the same soil samples, rested for 1 h before
being recapped for 2 h to measure SIR. Carbon dioxide was mea-
sured in the headspace using a Shimadzu GC model GC 17A, with
a thermal conductivity detector and a 168 mm HaySep 100/120
column. Dehydrogenase enzyme activity was measured using
2.5 g dry weight soil and acid and alkaline phosphatase enzyme
activity using 1 g dry weight soil as described by Tabatabai
(1994). Both enzyme reactions were measured using a Bio-Tek
microplate reader model EL311s.
2.3. Forage sampling and analysis
Forage herbage biomass was clipped close to the ground from 2
random 2 m
2
samples from each plot in May and August of 2005
and 2006, dried and weighed. Forage height was measured using
a rising plate meter. Each year after forage samples were taken
the plots were mowed for hay and then rotationally grazed with
sheep at an approximate stocking density of 4500 kg ha
1
. Stock-
ing duration varied from 2 to 7 days depending on available forage.
A subsample of forage biomass was analyzed for crude protein,
acid detergent fiber (ADF), neutral detergent fiber (NDF), total
digestible nutrients (TDN), relative feed value (RFV), Ca, P, K, Mg,
and Ash according to National Forage Testing Association methods
(Undersander et al., 1993).
2.4. Whole farm survey and animal health assessment
In the summer of 2009 a whole farm survey was conducted to
determine overall soil fertility and health. Composite soil samples
were taken from four fields on the farm, including the vegetable
garden and the former experimental site. Ten to twenty samples
were taken per field at a depth of 0–15 and 15–30 cm, thoroughly
homogenized and shipped to Soiltest Farm Consultants Inc. (Moses
Lake, WA) for analysis. Soil samples were passed through a 2 mm
sieve, stored at 4 °C until analyses, and then analyzed for the fol-
lowing properties according to recommended soil-testing methods
by Gavlak et al. (2003): Nitrate-nitrogen (N) was measured with
the chromotropic acid method; ammonium-N was measured with
the salicylate method; Olsen phosphorus and potassium were
measured; DTPA–Sorpitol extractable sulfur, boron, zinc, manga-
nese, copper and iron were measured; Soil pH and electrical con-
ductivity were measured in a 1:1 w/v water saturated paste;
calcium, magnesium and sodium were measured in a NH
4
OAc ex-
tract; cation exchange capacity was measured using the NH
4
replacement method; SMP soil buffer was measured and total
bases calculated by summation of extractable bases.
The health and productivity status of the farms sheep flock were
assessed by body condition scoring and reproductive success in
June and September of 2009. Farm economic viability was assessed
using farm records of purchases and sales.
2.5. Statistical analysis
Data were analyzed as a completely randomized design (CRD)
with treatment as whole plot and year (2005 and 2006) as subplot.
Soil properties were analyzed separately by depth. For forage anal-
ysis, data from the May and August sampling dates within year
were pooled to obtain average forage quality per year. Baseline
data were analyzed separately as a CRD. All statistics were ana-
lyzed using the SAS system for Windows version 9.1 ANOVA and
LSmeans (SAS Institute, Cary, NC). Data were checked for model
assumptions and transformed as necessary. When data were trans-
formed, LSmeans reported are in original units. Differences were
considered significant at p< 0.05 unless otherwise stated.
3. Results and discussion
Baseline data revealed no significant differences among plots at
the start of the experiment, with an initial soil pH of 6.0 at 0–10 cm
and 6.1 at 10–20 cm (data not shown). This soil pH is marginally
acidic; however, previous spot testing conducted by the farmer
showed soil pH of 5.5 in some areas.
After treatment, a few differences were seen within the 0–
10 cm depth (Table 3), but there were no differences among treat-
ments in any of the measured parameters at the 10–20 cm depth
(Table 4). Soil pH rose significantly after treatment from the base-
line pH of 6.0 in both limed and BD plots relative to the control in
the top 10 cm (Table 3). There was no significant treatment year
interaction indicating the treatment response was similar in both
years following treatment application. Soil pH in the limed treat-
ment was greatest at pH 6.6, with only a slight change in the un-
treated control at pH 6.2 and an intermediate change in the BD
treatment of pH 6.4. These differences are small and observed in
the top 10 cm of the soil only; nevertheless, the rise in pH in both
lime and BD spray treatments in the surface soil would be suffi-
cient to improve the availability of several essential nutrients
574 J.R. Reeve et al. / Agricultural Systems 104 (2011) 572–579
Author's personal copy
including nitrogen, phosphorus, calcium, magnesium and molyb-
denum (Brady and Weil, 2002b).
Readily mineralized carbon (Cmin) was greater and the
Cmic Cmin
1
ratio was lower in the limed treatments (Table 3).
This was due to a greater CO
2
release in the initial 10 days of soil
incubation and a lesser relative stimulation of CO
2
release after
the addition of soluble glucose to the limed soil. We saw no differ-
ences in microbial activity as measured by dehydrogenase and
phosphatase enzyme activities. Increased microbial activity,
microbial biomass, and soil respiration in response to liming have
been reported in lab experiments (Condron et al., 1993), forest sys-
tems (Marschner and Wilczynski, 1991; Andersson et al., 1994),
annual tillage systems (Haynes and Naidu, 1998), no-till systems
(Ekenler and Tabatabai, 2003; Fuentes et al., 2006), and grassland
systems (Rangel-Castro et al., 2004). Some studies indicate long-
term use of lime to have negative impacts on organic matter levels
in soils through increased microbial activity and C turnover (Kreut-
zer, 1995; Rangel-Castro et al., 2004). Others suggest soil C levels
can remain stable in limed soils if the increased C turnover is re-
placed through increased plant biomass production as a result of
improved nutrient availability (Kemmitt et al., 2006). Observations
of greater Cmin respiration, Cmic biomass (by SIR) and any CO
2
-
based measures of soil after liming treatment must be considered
with some reservation, however, as the inorganic carbonates of the
lime itself can contribute to increased CO
2
flux. Bertrand et al.
(2007) used labeled tracers to show increased CO
2
production from
limed soils originated from mineral sources not organic matter,
and cautions that increased soil respiration alone cannot be used
as evidence for projected organic matter loss. Thus the increased
Cmin measured from limed soils in this study was likely due to
continued lime decomposition, not an increased labile organic C
pool, as there was no corresponding increase in microbial enzy-
matic activity, biomass, or reduction in total soil C by treatment.
Further long-term monitoring of C dynamics in limed study sites
is needed to resolve this debate.
Neither liming nor BD treatment significantly changed forage
yield or height over the two years of this study (Table 5). Average
forage yields were 1170 kg ha
1
, which are somewhat low but
could be expected as the site could be considered unimproved
grassland; it had not been reseeded or received any external fertil-
ity inputs in at least 38 years. Bulk forage quality was relatively
low also, as characterized by a high ADF content (40.6–41.9%),
low crude protein (7.4–7.9%) and TDN (54.8–56.2%). While these
ranges are adequate for non-lactating sheep, lactating sheep as
were grazed in this study typically require forage crude protein
levels of at 9.5% and TDN around 70% (CAN, 1985). Forage P levels
for lactating sheep should be at least 0.18% which is higher than
the 0.15% measured in this study. Most measures of forage quality
were similar among the treatments; however, forage biomass from
limed plots had significantly (6% less) reduced crude protein as
compared to BD (p< 0.01) and (4% less) control (p< 0.05), (Table
5). These statistically significant differences are unlikely to be bio-
logically significant; however, as the crude protein was approxi-
mately 17–22% below that typically required for lactating sheep.
The relative feed value (RVF) which describes overall forage quality
was only 77–81 when good forage typically has an RVF of over 100.
Lack of yield response to lime in pastures in the absence or with
only minimal fertilizer inputs is not unprecedented (Malhi et al.,
1998; Malhi et al., 2002). This suggests that in low fertility pas-
tures, lime without additional fertilizers may not always increase
plant productivity. Low nutrient content may continue to override
pH improvements or beneficial chemical effects may be accompa-
nied by negative biological effects such as changes in mycorrhizal
associations (Wallander et al., 1997; Hart and Trevors, 2005). Soil
fertility measurements indicate this pasture was low in nitrogen,
potassium, phosphorus and sulfur (Tables 8 and 9).
To our knowledge this is the first study to show a soil pH effect
with use of the PFS and BD preparations. Unlike Colmenares and
Miguel (1999), however, we found no increase in forage dry matter
content in response to BD treatment. There is considerable vari-
ability reported in the literature on BD preparations which could
represent differences in quality of preparations, differences in site
response, as well as the possibility of statistical anomalies. While
our results will need to be confirmed our data suggest BD treat-
ment may have the potential to ameliorate soil pH. Moreover BD
treatment does not involve the mining and transportation of lim-
ited resources and BD field sprays can potentially be produced on
farm. From the perspective of the farmer, these findings indicate
Table 3
Means (n= 24) for soil analyses (depth 0–10 cm) conducted in years 2005 and 2006.
Parameter Lime Biodynamic Control
Total carbon% 5.04a 5.28a 6.03a
Total nitrogen% 0.488a 0.511a 0.575a
C:N ratio 10.3a 10.4a 10.5a
pH 6.6a 6.4b 6.2c
pH change from baseline 0.5a 0.3a 0.1a
Dehydrogenase (
l
TPF g
1
soil) 11.1a 11.2a 11.4a
Phosphatase (
l
p-nitrophenol g
1
soil) 518a 517a 494a
Readily mineralizable carbon or Cmin
(
l
gCg
1
soil)
118b 102a 98a
Basal microbial respiration (
l
gCg
1
soil) 5.5a 7.3a 5.0a
Microbial biomass carbon or Cmic
(
l
gCg
1
soil)
771a 926a 836a
Cmic/Cmin 7.3b 9.5a 10.2a
QCO
2
1000 7.5a 6.7a 6.7a
Means with different letters in each row are significant at P< 0.05.
Table 4
Means (n= 24) for soil analyses (depth 10–20 cm) conducted in years 2005 and 2006.
Parameter Lime Biodynamic Control
Total carbon (%) 4.48a 4.23a 4.55a
Total nitrogen (%) 0.439a 0.420a 0.451a
C:N ratio 10.2a 10.1a 10.1a
pH 6.5a 6.4a 6.3a
Dehydrogenase (
l
TPF g
1
soil) 9.3a 9.0a 8.9a
Phosphatase (
l
p-nitrophenol g
1
soil) 298a 287a 386a
Readily mineralizable carbon or Cmin
(
l
gCg
1
soil)
54a 48a 52a
Basal microbial respiration (
l
gCg
1
soil) 4.4a 3.6a 3.9a
Microbial biomass carbon or Cmic
(
l
gCg
1
soil)
562a 505a 568a
Cmic/Cmin 11.9a 11.2a 11.7a
QCO
2
1000 7.0a 7.0a 7.0a
Means with different letters in each row are significant at P< 0.05.
Table 5
Means (n= 24) for forage analyses conducted in years 2005 and 2006.
Parameter Lime Biodynamic Control
Plant biomass (dry kg ha
1
) 1190a 1220a 1090a
Plant height (mm) 678a 711a 681a
Crude protein (%) 7.4b 7.9a 7.6a
Acid digestible fiber (%) 41.9a 41.6a 40.6a
Neutral digestible fiber (%) 67.6a 67.8a 66.3a
Total digestible nutrients (%) 54.8a 55.0a 56.2a
Relative feed value 77.9a 77.8a 81.1a
Ca (%) 0.45a 0.44a 0.44a
P (%) 0.15a 0.15a 0.15a
K (%) 2.0a 2.1a 2.1a
Mg (%) 0.19a 0.18a 0.19a
Ash (%) 8.3a 8.7a 7.9a
Means with different letters in each row are significant at P< 0.05.
J.R. Reeve et al. / Agricultural Systems 104 (2011) 572–579 575
Author's personal copy
that lime is not a beneficial input to this field at this time. Using BD
preparations to moderate pH or using no treatment saves the ex-
pense of liming and maintains low non-renewable resource use
while producing similar or better forage quality than liming.
3.1. Sustainability of S&S Homestead Farm
As described above, S&S Homestead Farm has been operating
organically for over 30 years and represents an example of a farm
operated on the principles of a closed system Edens and Haynes
(1982). The boundaries of the system do not represent the actual
farm boundaries but include the local community, in this case Lo-
pez Island. In order to assess the overall sustainability of the farm,
an informal life cycle analysis was conducted (Heller and Keoleian,
2000)(Table 6). The 20 ha farm is mostly in pasture and produces
beef, pork, lamb, a wide selection of vegetables and fruit for sale
and home consumption, and a CSA operated on 1.1 ha of the farm.
With the exception of the CSA, the farm also grows the majority of
its own fertility and animal feed. Compost is made from spoiled
straw and hay, manure from two dairy cows, and slaughter by-
products, effectively recycling on farm wastes. This compost is
used exclusively in the vegetable and fruit growing operations.
Pastures receive no inputs other than urine and manure deposited
by grazing animals. The farm also has an extensive gravity fed rain-
water collection system that stores water in underground tanks
and a holding pond. Water is pumped from the pond using a solar
powered pump and used for irrigating the vegetable gardens. Pas-
tures are not irrigated and rely solely on rainfall for moisture.
The farm is economically stable. As an example, in 2007 gross
returns for S&S Homestead Farm were $42,666, 42% from animal
products, 25% from fruits and vegetables, 19% from hay and grain,
and 10% in services provided to the CSA (Table 7). Only 27%
($11,707) of the gross farm revenue came from the off-farm sale
of meat and vegetables. The remainder represents services ren-
dered to the CSA and dollars saved through on farm consumption
of meat, eggs and dairy products, fruits, vegetables and animal
feed. Additional gross returns of $10,541 were earned by S&S Cen-
ter for Sustainable Agriculture which hosts on-farm workshops and
training days as well as interfacing with a local school in a food to
farm program. Finally, gross returns of $20,146 were generated by
Lopez Community Farm CSA, which is run as a subsidiary enter-
prise by management trainees for their own profit. The gross re-
turns for all three farm enterprises for 2007 totaled $73,263.
Direct production costs for S&S Homestead Farm and S&S Cen-
ter for Sustainable Agriculture (including on-farm consumption of
products) totaled $53,850 and indirect costs (amortization)
$10,268. Total expenditures were $64,118 and the total farm profit
was $9145 of which $8282 was paid to the CSA farm operators as
compensation.
The farm exports nutrients through off farm sale of animal and
vegetable products. The farm sold 6941 kg of meat products which
represented 59% of the total generated in 2007. One hundred and
Table 6
Life Cycle Sustainability Indicators for S&S Homestead Farm.
Life Cycle Stage Indicators
Economic Social Environmental
Farm production – Economically stable with marginal
return on investment
– Farmers nearing retirement age – Forage based system. Potential for soil loss
very low
– Farm income sufficient to capitalize
operating and infrastructure costs
– Limit on number of dwellings allowed on property
makes handover to next generation challenging
– Some net loss of nutrients likely from
export, leaching and denitrification
– Farm start up from farmer savings, self
capitalizing since 1994
– Two full time farmers plus summer interns – No synthetic inputs
– No debt – No farm wages for owners, CSA profits returned to
managers
– Air pollutants low
– Spouse works off farm – Farmers, CSA managers and interns consume farm
produced food
– Species diversity high
– CSA manager works part time at school
implementing farm-to-school program
– Actively involved in intern training, farm to school
program, and other community educational programs
– Rain based irrigation
– No government subsidies – Energy partly provided by solar system.
Current fossil fuel use less than 378 L per
annum
– Very low harvest loss to pests and
diseases
– Animals are healthy and live year-round
on pasture with shelter
Origin of genetic
resources
– Some seed saved on farm, most is
purchased
– Most seed purchased from small organic producers – All seeds naturally pollinated
– Animal breeding for desired
characteristics conducted on farm
– Some livestock, seeds and seedlings sold as local
breeding stock, forming a network of genetic resources
– Hybrid seed avoided
– Breeding stock obtained locally when
appropriate breeds available
– Natural reproduction of animals
– Disease resistant seed varieties and
animals selected
– Shipping of seeds and stock is minimized
Food processing
and
distribution
– Farm products minimally processed and
produced on farm
– High quality meat and vegetables produced – Mobile slaughter unit visits farm on site
– Interns participate in food processing – CSA members collect weekly shares at farm – Local consumers collect meat and
vegetables from farm in personal vehicles
– Products marketed locally or consumed
on farm
– No data on product safety –presumed safe
– Intern satisfaction not evaluated
Consumption
and waste
– Farm family and interns spend little on
outside foodstuffs
– Interns share meals of farm-produced foods – All farm/food waste composted on farm
– No money spent on food disposal – Some farm products consumed at local schools
– Excess donated to local food bank
576 J.R. Reeve et al. / Agricultural Systems 104 (2011) 572–579
Author's personal copy
eighty-one kilograms of vegetables were sold off farm from the
vegetable garden and a larger though unrecorded amount from
the CSA. Few inputs are purchased. Some seed is saved but the
majority is purchased from a local company that tests all varieties
for local adaption. Open pollinated varieties are purchased when-
ever available with the exception of sweet corn. Replacement ani-
mals (three pigs) are purchased yearly and some supplemental
grain is also purchased in years suffering poor grain yield. In addi-
tion to using compost generated on farm, the CSA purchased
81 kg ha
1
each of blood meal, greensand, rock phosphate, and
lime, 61 kg ha
1
gypsum, and 1.4 kg ha
1
zinc and boron and 27
metric tons of woodchip mulch in 2007.
All farm operations are conducted by the farmer and his wife
and two to five seasonal interns. Interns receive lodging and food
and a modest stipend. The CSA is managed by a separate couple
who are paid exclusively through revenue generated by the CSA.
The farm also operates a successful farm to school program. High
school students come to the farm twice per week for about an hour
to engage in various farm activities such as bucking hay, planting
row crops, and weeding. Students learn about the particular activ-
ity in the context of the whole farm system and the larger ecolog-
ical setting. Students also learn how to bake bread, make
sauerkraut, cheese, and sausage, and learn about nutrition and
health. The farm also runs workshops and conferences though
the S&S Center for Sustainable Agriculture. The farm balances its
cash flows each year and receives no government subsidies. The
farm has no equipment overhead or farm loans. It must be empha-
sized that it is not the ultimate goal of the farm to make as much
profit as possible, but rather to maintain economic sustainability
within the carrying capacity of the land.
Soil tests taken from three pastures and one of the vegetable
gardens show that with the exception of the vegetable garden,
the majority of the farm is low in nitrogen, potassium, phosphorus
and sulfur (Tables 8 and 9). The vegetable garden is actually high in
nutrients suggesting that nutrients are returned to this area in dis-
proportionate quantities. While no records of soil fertility prior to
organic conversion is available, the low levels of P, K and S in the
pastures are a concern as this indicates the possibility that nutri-
ents removed through the sale of meat are not being sufficiently
replaced. Based on the volume of sales relative to purchases (see
above) this seems likely.
Despite the concern over adequate replacement of nutrients
from pastures sold off farm, it is important to note that soil fertility
and forage quality measured against conventional farming stan-
dards is problematic for the assessment of organic farming. Firstly,
soil tests that measure labile soil nutrients extracted in solution
may not adequately reflect available nutrients in organic systems.
For example, organic and inorganic P mineralization is increased
under low levels of soluble P (Smeck, 1985; Trolove et al., 1996;
Oehl et al., 2004). Secondly, conventional nutrient recommenda-
tions on soil tests are linked to maximum yield targets. This is be-
cause in conventional systems, the low cost of fertilizer has meant
that inputs needed for maximum economic return have closely
matched fertility targets for maximum yield, despite the law of
diminishing returns operating at high input rates (Tisdale et al.,
Table 8
Soil nutrient profiles from three pastures and one vegetable garden at 0–15 cm S&S
Homestead Farm. Pasture 1 represents the study area for the lime response trial.
Soil property Garden 0–
15 cm
Pasture 1
0–15 cm
Pasture 2
0–15 cm
Pasture 3
0–15 cm
Nitrate-N (mg kg
1
) 48.9 2.5 1.5 2.0
Ammonium-
N (mg kg
1
)
14.4 5.4 4.0 4.9
Organic matter
gkg
1
)
12 9.8 6.4 5.8
Olsen phosphorus
(mg kg
1
)
132 9.0 19 11
Potassium (mg kg
1
) 1638 151 100 194
Sulfate-S (mg kg
1
)39 13 10 10
Boron (mg kg
1
) 0.80 0.83 0.43 0.70
Zinc (mg kg
1
) 12.5 2.6 1.2 1.4
Manganese
(mg kg
1
)
18.2 28.5 14.9 29.6
Copper (mg kg
1
) 2.5 4.5 2.2 2.3
Iron (mg kg
1
) 166 237 155 196
pH 6.6 6.1 6.1 6.2
EC saturated past
(mmhos cm
1
)
2.44 0.49 0.34 0.26
Calcium (meq
100 g
1
)
10.6 13.6 5.8 5.3
Magnesium (mq
100 g
1
)
4.9 6.5 2.5 2.3
Sodium (meq
100 g
1
)
0.59 0.54 0.30 0.21
CEC (meq 100 g
1
) 25.9 34.8 14.6 14.6
Buffer capacity (pH) 6.9 6.3 6.6 6.7
Total bases (meq
100 g
1
)
20.3 21.1 8.8 8.3
Table 7
Farm enterprise budget for 2007.
Farm income
S&S Homestead Farm $42,666
S&S Center for Sustainable Agriculture $10,451
Lopez Community Farm CSA $20,146
Total returns $73,263
Farm expenses
Direct costs $53,850
Indirect costs $10,268
Total expenses $64,118
Profit $9145
Table 9
Soil nutrient profiles from three pastures and one vegetable garden at 15–30 cm S&S
Homestead Farm. Pasture 1 represents the study area for the lime response trial.
Soil property Garden
15–30 cm
Pasture 1
15–30 cm
Pasture 2
15–30 cm
Pasture 3
15–30 cm
Nitrate-N (mg kg
1
) 53.7 0.8 1.6 3.4
Ammonium-N (mg
kg
1
)
4.3 3.8 3.3 3.0
Organic matter
(g kg
1
)
8.4 5.6 3.9 3.7
Olsen phosphorus
(mg kg
1
)
93 6.0 23 10
Potassium
(mg kg
1
)
736 84 64 143
Sulfate-S (mg kg
1
)25 9 6 7
Boron (mg kg
1
) 0.70 0.72 0.24 0.20
Zinc (mg kg
1
) 9.8 1.5 0.6 0.5
Manganese
(mg kg
1
)
8.7 8.5 8.0 7.4
Copper (mg kg
1
) 2.7 4.6 1.5 1.4
Iron (mg kg
1
) 190 216 116 87
pH 5.9 6.2 6.1 6.3
EC saturated past
(mmhos cm
1
)
1.87 0.23 0.23 0.26
Calcium (meq
100 g
1
)
10.3 11.3 4.4 5.4
Magnesium (meq
100 g
1
)
4.5 5.6 1.8 2.2
Sodium (meq
100 g
1
)
0.35 0.45 0.24 0.21
CEC (meq 100 g
1
) 22.2 24.5 10.8 11.5
Buffer capacity
(pH)
6.6 6.5 6.7 6.8
Total bases (meq
100 g
1
)
17.0 17.5 6.6 8.1
J.R. Reeve et al. / Agricultural Systems 104 (2011) 572–579 577
Author's personal copy
1993). This may not be the case for many organic systems, (and
increasingly for conventional systems) particularly when inputs
are expensive or not readily available. Regular soil testing should
be an integral part of organic farm nutrient management plans
as a tool for assessing long-term trends in soil fertility, but inter-
pretations of standard fertilizer recommendations should take
these additional factors into account.
Sheep health was assessed as an example of the diverse live-
stock on S&S Homestead Farm. The flock was established in 1994
and consists of eight breeding ewes and one ram. The initial flock
consisted of purebred Suffolks but due to initial health problems
the flock was crossbred over the years with a series of different
rams in order to increase genetic diversity. The initial ram was a
purebred Romney followed after several seasons by a Polypay
ram. The sheep flock became stronger, more self-sufficient, and
durable. The Polypay was replaced with a Churro ram but this re-
sulted in lambs that were flighty, rough fleeced and not of desir-
able finish and frame. The Churro was replaced with a Romney/
Cheviot ram, which has sired the flock for the past two years.
In order to assess the weight gain of the lambs and health of the
ewes, the flock was evaluated for general health, growth rate, and
frame condition (BANRELS, 2008) in the summer of 2009. Unlike
conventional sheep farming systems the lambs are not weaned
but remain with their dams until they are almost ready for slaugh-
ter. Lambing is typically 140% which is similar to that of conven-
tional flocks. Lambs grew at 0.7–1.1 kg per day. This is an
acceptable rate of growth for conventional sheep enterprises, given
that these lambs are not of large frame size. Moreover, the cus-
tomer or organic base requests, and is satisfied with, the size of
these market lambs, which average from 39 to 45 kg at slaughter.
Singles are slaughtered in the fall of the year they were born, and
twins are slaughtered as yearlings the following spring. The cus-
tomer base continues to be willing to pay a premium for these
lambs due in their words, to consistent superior taste and tender-
ness. Another product that comes from this flock is tanned hides.
The quality of the hides was observed to be superior regarding in-
tact hides (no holes, tears, scarring).
The sheep have year round access to pasture consisting of a con-
siderable number of paddocks, through which they are rotated on a
daily or weekly basis depending on season, weather and pasture
growth. In addition to year round access to forage and trace miner-
als, ewes are given 500 g of barley per day during early lactation.
Four to six week lambs may be given molasses during unusually
cold or wet spring seasons. None of the sheep are vaccinated or
treated with any form of anthelmintics. Since the genetic diversity
of the flock was increased there have not been any illnesses. De-
spite the low quality of the forage by conventional standards, the
stocking density together with supplemental grain appears to be
sufficient to provide adequate nutrition to the sheep. Both ewes
and lambs were observed to be in top condition based on body
scoring through palpation and other measurements.
Regarding the forage quality, it is important to note that, unlike
a typical conventional pasture, this pasture contains significant
percentages of different legumes and forbes (Table 2). Bulk forage
analyses may underestimate the forage quality as taken in by
sheep since foraging behavior allows them to select the more pal-
atable and more nutritious plants. Burkitt et al. (2007b) showed
that while milk yields were lower, parasite loads of biodynamic
and conventional dairy herds were similar despite the biodynamic
animals receiving no anthelmintics. Diverse plant mixtures, some
high in plant secondary compounds, may allow animals to self
medicate through foraging behavior (Provenza et al., 2003). Eating
plants that contain tannins for example, reduces the load of inter-
nal parasites (Min and Hart, 2003) alleviates bloat (Waghorn,
1990) enhances protein uptake (Barry et al., 2001) and improves
immune response (Niezen et al., 2002). The access to diverse forage
may explain their excellent weight gain and health assessment de-
spite the low forage quality when compared to conventional
standards.
4. Conclusions
So is S&S Homestead Farm achieving its goals of economic, envi-
ronmental and social sustainability? As described above, the farm
while not highly profitable is certainly economically stable, with
a balanced cash flow. In terms of a whole farm system or life cycle
analysis S&S Homestead Farm meets the criteria for economic,
environmental and social sustainability. Nevertheless there are
concerns the farm may not adequately balance soil nutrient bud-
gets, in particular nutrient returns to pastures from the off farm
sale of meat products. This is a concern that applies to many biody-
namic and closed systems organic farms and could be addressed
through increasing off-farm purchases of targeted nutrients when
needed. Relying on inputs such as lime and rock phosphate that
have been mined and transported long distances cannot ultimately
be thought of as a sustainable long-term solution however. An-
other approach would be to try to increase mineral weathering
of nutrients through stimulating soil microbial populations.
We tested this hypothesis by evaluating the effects of liming
and BD preparations on soil pH, microbial activity, and forage yield
and quality in a mixed pasture on S&S Homestead Farm. While
lime was most effective at raising soil pH, BD preparations were
intermediate in effectiveness when compared to untreated con-
trols. No increase in microbial biomass or activity was observed
as a result of any of the treatments. A slight negative impact on for-
age crude protein due to lime treatment was observed, although
the magnitude of this effect is unlikely to be biologically significant
due to the overall low forage quality. Lime increased the measured
Cmin and reduced Cmic Cmin
1
in the top 10 cm of the soil. No dif-
ferences were observed in soil C or microbial activity and so we
suggest that the greater CO
2
release was due to continued dissolu-
tion of the lime.
As environmental, economic, and energy pressures increase the
urgency of improving long-term agricultural sustainability, the use
of local and on-farm resources to generate intrinsic fertility within
their farm system and limit external inputs becomes more impor-
tant. This study found potential to use biodynamic preparations,
which can be produced on-farm, to treat moderate soil acidity.
Our whole farm survey also highlights the conflicts that can occur
between achieving long-term environmental and social sustain-
ability under often harsh economic realities.
Acknowledgements
This research was supported by Western SARE through a farmer
rancher grant, the Crops and Soils Department at Washington State
University and the Utah Agricultural Experiment Station and ap-
proved as journal paper number 8222. Thanks in particular to Dr.
Steve Fransen for assistance with proposal development and forage
data collection and to Dr. Mike Hackett for conducting the sheep
health assessment. Many thanks to Dr. Marc Evans for statistical
consulting, to Dr. Stuart Higgins for statistical assistance, and to
Margaret Davies for much needed assistance in the laboratory.
An additional thanks to Ron Bolton for assistance with numerous
computer related problems and questions.
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... This is in line with Reeve et al. (2010), who report no differences in terms of pH, mineral elements, C/N ratio, NO 3 -N, and NH 4 + -N between a BD compost and an untreated compost. However, in a later study, Reeve et al. (2011) stated that, under changing circumstances, both the Pfeiffer field spray and other BD preparations were found to be moderately effective in raising soil pH. ...
... In terms of microbial activity, conflicting results are reported by Reeve et al. (2010) and Reeve et al. (2011). In the first study, they reported the occasional superiority of BD compost to untreated compost, but in the latter, no effect of BD compost was found. ...
... In the first study, they reported the occasional superiority of BD compost to untreated compost, but in the latter, no effect of BD compost was found. In addition, Reeve et al. (2011) found no effect on forage yield between fields treated with BD compost and with untreated compost but reported the occasional superiority of the impact of BD compost on wheat seedling height; results showed that a 1% extract of BD compost grew 7% taller wheat seedlings than a 1% extract of untreated compost did (Reeve et al. 2010). ...
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Biodynamic agriculture (BD agriculture) was presented as an alternative form of agriculture by the philosopher Rudolf Steiner and is nowadays considered one of the forms of organic agriculture. The objective of the present manuscript is to critically review international scientific literature on biodynamic agriculture as published in highly ranked journals and to assess its performance. This review was based on a structured literature survey of peer-reviewed journals indexed on the Web of Science™ (WoS) Core Collection database carried out from 1985 until 2018. We found 147 publications of studies in journals with an impact factor. Of these, 93 focused on biodynamic agricultural practices, 26 on the sustainability of the biodynamic method, and 28 on the food quality of biodynamic products. The results of the literature review showed that the BD method enhances soil quality and biodiversity. Instead, further efforts are needed to implement knowledge on the socio-economic sustainability and food quality aspects of BD products. One particularly promising topic of research consists in the assessment of microbial activity and the potential that microbiomes have in BD farms to enhance soil fertility and human health following the One Health approach. Moreover, it is critical that such subjects be investigated using a systemic approach. We conclude that BD agriculture could provide benefits for the environment and that further efforts should be made with research and innovation activities to provide additional information to farmers, policy makers, and stakeholders regarding this type of organic agriculture.
... De maneira geral, interpretando os conceitos, todos expressam o quanto é necessário o estabelecimento de um novo modelo produtivo, que de forma racional utilize os recursos naturais e consiga manter-se em longo prazo. Assim, quando se fala de agricultura sustentável, refere-se a estilos de agriculturas fundamentadas na ecologia, que cumpram todas as características de solidariedade entre as gerações (Caporal & Costabeber, 2005;Reeve et al., 2011). ...
... As vertentes que deram o pontapé inicial para a agricultura sustentável têm bases agroecológicas (Darolt, 2007). Inicialmente, a agroecologia defendia a diversificação de culturas, o uso racional de recursos naturais, a otimização dos recursos locais, ou seja, uma produção saudável que respeitasse o meio ambiente, e aos poucos, foi integrando outras questões, como movimentos e organizações sociais (Reeve et al., 2011;Barboza et al., 2012). ...
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The objective of this review was to compare two models of sustainable agriculture, demonstrating their advantages and disadvantages and correlating them with each other. The diverse contemporary agricultural practices comprise from alternative models of agriculture, such as permaculture, organic farming, organic, biodynamic, that are considered sustainable, and intensive production models, that present several negative points, contrasting with alternative models. The search for a less aggressive agriculture to the environment, what stay productive in the long run, it has been a constant concern of researchers and producers. Agricultural models are similar to each other, what differs are some practices that do not are allowed in all, and its foundation bases. In this review, two models were more approached in a simplified way, to the perception of their concepts and fundamental bases, showing what differentiates them, and that still leads to the same goal, creating an ecosystem independent of external resources.
... The preparation 500 is commonly distributed on the soil at a rate of 100 g/ha in Autumn and in Spring, while 501 is spread over the canopy using 3-5 g/ha one or more times during the plant vegetative growth, depending on the seasonal climatic trend. The distribution of the preparations in the vineyards was found to enhance the vegetative-reproductive balance of grape plants [6]. Positive effects on the application of preparations on the soil microbiology and fertility [7,8], and on the plant resistance to biotic and abiotic stresses, were also evidenced in different grape varieties [9,10]. ...
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Background There is a need for new approaches in agriculture to improve safety of final products as well as to increase environmental acceptability. In this paper, the biodynamic preparation 501 (horn silica) was sprayed on Vitis vinifera (L.) cv Garganega plants in two vineyards located in Veneto region, North-East Italy. Leaf samples were collected on the day of 501-treatment and 11 days later, and berries were sampled at harvest time. Leaves and berries samples were analysed combining targeted and untargeted measurements related to primary metabolism (pigment, element and amino acid contents) and to secondary metabolism. Chlorophyll content in leaves, and amino acid and element (C, N, S) analysis in berries were combined with untargeted UPLC-QTOF metabolomics. Results The discriminant compounds related to the 501-treatment were annotated on the basis of accurate MS and fragmentation and were identified as secondary metabolites, namely phenolic constituents belonging to the shikimate pathway. The level of most of the identified compounds increased in plants treated with 501 preparation. Conclusions Results highlight the prominent value of the metabolomic approach to elucidate the role of the 501 applications on grapevine secondary metabolism. Graphical Abstract
... Biodynamic preparations are claimed to vitalize the soil, enrich it with macro and micronutrients, enhance seed germination, root formation, improve photosynthesis activity, strengthened plant immune system and better quality of fruits and seeds (Reeve et al., 2011). Yet the principal behind their bioenhancing power has still not been much worked out. ...
Article
Aim: Biodynamic farming system involves use of 8 different biodynamic preparations (BD 500-BD 507). Multi functionality of any ecosystem is due to its microbial diversity and community composition of microbes. So the present study was aimed to determine the total fungal population viz. unculturable ones, metagenomic analysis was done. Methodology: In the present study, 18S rDNA sequencing of V3-V4 amplicon regions was performed to identify and characterize fungal diversity, which existed in these preparations. Results: Alpha diversity was found to be maximum in BD506 with 868 OTU (operational taxanomic units) and minimum in BD507 with 254 OTU. At phylum level, the most abundant phylum was Ascomycota as recorded in 7 BD preparations with exception in the BD 500 (Unassigned). At genus level highest percentage of OTU abundance was observed for unassigned genus in all BD preparations, except Mortierella in BD 500 and BD 502; Microascus in BD 501 and BD504; Gymnoascus in BD503, Scedosporium in BD 505, Mucor in BD 506 and Hyphopichia in BD 507. On the basis of species diversity, BD502, 503 and 506 showed high percentage of OTU abundance for Mucor racemosus, while Mortierella oligospora was abundant in BD500, Dipodascus geotrichum in BD 501, Kernia pachypleura in BD504, Petriella setifera in BD505 and Hyphopichia burtonii in BD 507. Interpretation: This indicated a unqiue class of fungus predominating each type of BD preparation. Furthermore, a large proportion of unassigned fungi at phylum and genus level were detected in metagenome analysis which might have specific roles in contributing for their overall effectiveness of each kind of BD preparations.
... ,Mäder et al. (2002),Reeve et al. (2005),Cookson et al. (2006),Hartmann et al. (2006),Widmer et al. (2006),Burkitt et al. (2007),Esperschutz et al. (2007),Fliessbach et al. (2007),Probst et al. (2007),Birkhofer et al. (2008),Reeve et al. (2011), Jaffuel et al. (2016, Meissner et al. (2019) Bacteria Cookson et al. (2006), Widmer et al. (2006), Esperschutz et al. (2007), Birkhofer et al. (2008), Heger et al. (2012), Hartmann et al. (2015), Burns et al. (2016), Hendgen et al. (2018) Fungi Carpenter-Boggs et al. (2000a), Mäder et al. (2002), Oehl et al. (2004), Esperschutz et al. (2007), Birkhofer et al. (2008), Hartmann et al. (2015), Morrison-Whittle et al. (2017), Hendgen et al. (2018) Nematodes Birkhofer et al. (2008), Jaffuel et al. (2016) Micro-arthropodes Burkitt et al. (2007), Birkhofer et al. (2008) Micro-arthropodes Mäder et al. (2002), Birkhofer et al. (2008) Earthworms Carpenter-Boggs et al. (2000a), Mäder et al. (2002), Reeve et al. (2005), Birkhofer et al. (2008), Meissner et al. (2019) Soil conservation farming Total microorganisms Henneron et al. (2015) Bacteria Henneron et al. (2015) Fungi Henneron et al. (2015) Nematodes Djigal et al. (2012), Henneron et al. (2015) Micro-arthropodes Djigal et al. (2012), Henneron et al. (2015), Hernández et al. (2017) Earthworms Henneron et al. (2015), Hernández et al. (2017) Cumulative number of publications over the 2000-2020 in which farming systems are compared among all the publications of the collection (several pairs were compared in some publications). The number of publications about the impact of the farming system on the soil ecological quality has been increasing since 2000. ...
Article
The productivist model implemented after the second world war has succeeded in improving production to meet growing demands for food, but it has also deeply affected soil physicochemical properties, as well as of aboveground and belowground biodiversity. Alternative farming systems such as organic farming, biodynamic farming and soil conservation farming are actually developing to enhance the sustainability of farming systems. Although the impact of agricultural practices on soil ecological quality is well known, there is little knowledge on the impact of the different farming systems as a whole. Here, we analysed the impact of the main farming systems on soil biodiversity and functioning, reported in about 100 scientific publications. We found that conventional, organic, and biodynamic systems are the most widely studied, whereas soil conservation farming is poorly documented. Soil biological indicators are improved by ca. 70% in organic farming and biodynamic farming relative to conventional farming. 43% of soil bioindicators are improved in biodynamic farming relatively to organic farming. Soil conservation farming scores better than conventional farming for 57% of the indicators. Therefore, biodynamic farming displays the highest soil ecological quality, followed by organic farming, soil conservation farming and, last, conventional farming. Organic fertilisation and longer crop rotations are the most favourable practices, whereas pesticides and soil tillage are the most deleterious ones. The review also evidences a lack of studies on soil conservation farming and on bioindicators of the soil fauna.
... Some articles have addressed environmentally friendly agricultural systems such as organic farming [190][191][192][193][194] and agro-ecology [190,195,196], biodynamic agriculture [197,198], and conservation agriculture [199]. Migliorini and Wezel [190] suggested that "Both agroecology and organic agriculture offer promising contributions for the future development of sustainable agricultural production and food systems, especially if their principles and practices converge to a transformative approach and that impedes the conventionalisation of agrofood systems". ...
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Agri-food systems (AFS) have been central in the debate on sustainable development. Despite this growing interest in AFS, comprehensive analyses of the scholarly literature are hard to find. Therefore, the present systematic review delineated the contours of this growing research strand and analyzed how it relates to sustainability. A search performed on the Web of Science in January 2020 yielded 1389 documents, and 1289 were selected and underwent bibliometric and topical analyses. The topical analysis was informed by the SAFA (Sustainability Assessment of Food and Agriculture systems) approach of FAO and structured along four dimensions viz. environment, economy, society and culture, and policy and governance. The review shows an increasing interest in AFS with an exponential increase in publications number. However, the study field is north-biased and dominated by researchers and organizations from developed countries. Moreover, the analysis suggests that while environmental aspects are sufficiently addressed, social, economic, and political ones are generally overlooked. The paper ends by providing directions for future research and listing some topics to be integrated into a comprehensive, multidisciplinary agenda addressing the multifaceted (un)sustainability of AFS. It makes the case for adopting a holistic, 4-P (planet, people, profit, policy) approach in agri-food system studies.
... Higher dehydrogenase activity in BD treated compost and soil receiving organic and biodynamic preparations has been reported by Carpenter -Boggs et al. (2000b) and Rana et al. (2015), respectively. Wheat seedlings receiving 1% BD-treated compost extract have been reported to have higher root and shoot biomass (Reeve et al., 2011). Similarly, Valdez and Fernandez (2008) reported higher root length and biomass in rice varieties under biodynamic production system control or pesticide treatment. ...
Article
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Aim: To study the role of microorganisms behind their bioenhancing, biocontrol properties, their enzymatic potential, and characterization of high performing microbial isolates on molecular basis. Methodology: Dominant culturable microbes including bacteria and fungi were isolated from biodynamic preparations and screened on the basis of plant-growth promoting (PGP) activities viz., ammonia production, phosphate solubilization, siderophore production, hydrogen cyanide production, seed germination efficacy and biocontrol properties. The dominant and effective microorganisms were screened for enzymes activities viz., pectinase, cellulase and amylase. The selected bacterial and fungal isolates, exhibiting higher enzyme activities, were subjected to molecular characterization. Results: Out of 68 bacterial and 25 fungal isolates from 8 biodynamic preparations (BD 500 - BD 507), 15 bacterial isolates exhibited high plant growth promoting activities while 10 bacterial isolates exhibited biocontrol activity against pathogens. Bacillus licheniformis isolated from BD 504, expressed high pectinase (2.595 U ml-1 min-1), cellulase (0.308 U ml-1 min-1) and amylase (0.418 U ml-1 min-1) activities. Fungal isolates with high enzymatic activities, were isolated from BD 500, 503 and 506, respectively. Interpretation: Microorganism isolates from biodynamic preparations possessed strong plant growth promoting, biocontrol and enzymatic properties, which might be responsible for the efficacy of organic preparations under field conditions.
... It causes leaf discolouration, stunted growth, reduced tillar numbers and sterile or partly filled grains) present in the rice crops and the recovery of crop vitality. Reeve et al. (2011) reported that wheat seedlings receiving 1% BD-treated compost extract had similar root and shoot biomass as the fertilized seedlings and found to be significantly higher than the untreated compost. Sharma et al. (2012) reported that the application of BD 500 and BD 501 in combination with farmyard manure gave significantly higher yield and harvest index in cumin in comparison to other treatments and control. ...
Article
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Organic agriculture systems aim primarily at use of naturally occurring ecological processes rather than external inputs, to manage crops and livestock. These farming systems emphasize on ecofriendly methods of insect, pest and weed control. Biodiversity is the key component of organic agrisystems responsible for its efficacy. According to IFOAM (International Federation of Organic Agriculture Movements) organic production methods are those where at least 95% of the ingredients used for agriculture purposes are organic in nature. Latter content less than 70% may not refer to organic production methods. Organic farming systems work on nature's principles; improve agro ecosystem health including soil biological activity and product quality. The most followed organic farming systems are Permaculture, Panchagavya farming, Rishi Krishi, Natueco farming, Zero budget natural farming, Biodynamic farming etc. Enormous literature and supportive materials are available to justify the use of these farming systems to combat soil pollution created by use of various chemicals. However, when it comes to scientific explanation, the work is scattered. A common person may develop the assumption that these systems might possess some supernatural or magical curing ability. However, these preparations work on scientific principles mostly powered by microbes and their metabolic products. In the present review, research on various organic preparations, with special reference to their microbial properties, has been compiled and analysed. The review will be of immense benefit to students, researchers and strategy planners working in the field of organic farming.
Article
The integration of carrying capacity and sustainable development (sustainability) has prevailed since the end of the 20th century, but the connotation evolution and practice of carrying capacity for the United Nations Sustainable Development Goals (SDGs) have not been fully reviewed. Scientific measurement analysis and visualization are helpful to reflect the global picture of the connotation evolution and the practice in the field of carrying capacity for SDGs. This work retrieved the literature in the core collection database of Web of Science with topic words “carrying capacity and sustainable development” or “carrying capacity and sustainability” from 1985 to 2020. A set of 897 records were obtained as the data source. First, the evolution trend and mutation point detection, the theme mining and clustering, the citation chronology chart were visualized using the bibliometric analysis. Then, the focus of carrying capacity for SDGs and the main way to improve were summarized from the economic, environmental and social dimensions by researchers' intervention. This work examined the connotation and practice of carrying capacity for SDGs as thoroughly as possible, we attempted to supplement more meaning understanding, nuances, and critical thinking, and the current challenges and future prospects were summarized. It is expected that it will inspire new opportunities for academic research and practical applications, as well as enable policy managers to pay full attention to the potentially important value of carrying capacity in promoting the realization of SDGs.
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Mor humus samples from separate plots in a field-liming experiment in southern Sweden were incubated in a leaching experiment. Lime applications of 0.16, 0.35, and 0.88 kg/m2 dolomite lime were made 7 y before sampling. The leachates from the two highest lime applications had a pH of 7.0 and 5.3, respectively. The control and the lowest lime application had a pH of 3.9. Humus material receiving the largest lime application also showed the highest level of dissolved organic carbon (DOC) leaching (180 mg DOC/L) during the first 100 d of the experiment, probably owing to the increased negative charge caused by the high pH, which increased the solubility. The DOC concentration decreased in all treatments towards the end of the experiment owing to an increase in protonation caused by nitrate formation (nitrification). The C/S ratio in the organic matter of the leachates from the limed humus was lower than that in the control leachates. A positive correlation between DOC leaching and biological activity, measured as soil respiration, was found in humus material that had received the two highest lime applications.
Chapter
On the basis of a field experiment in Norway spruce with acid irrigation and compensatory liming of the soil surface (Höglwald, S-Bavaria), liming effects are described as lime dissolution rate, transformation of carbonate buffer to exchange buffer, time required for deacidification of soil and drainage water, mobilization of Cu and Pb, changes in soil organisms, humus decomposition, and nitrogen turnover. It was shown that lime dissolution followed an exponentially decreasing curve. 4 t ha-1 dolomitic lime were dissolved within 6 years. Additional acid irrigation of 4 kmol H+ ha-1 yr-1 as sulphuric acid speeded up the lime dissolution to about 4 years. After dissolution of lime about 70% of Ca and about 30% of Mg, both originating from lime dissolution, are retained in the surface humus layer, loading the exchange buffer capacity there. Liming acted as a protection against acid irrigation but the extension of soil deacidification downwards proceeded slowly due to the high base neutralizing capacity of protonated functional groups of the organic matter. The main depth effect is caused by Mg translocation. A significant increase of organic Cu complexes occurred due to mobilization of water soluble humus decomposition products. The effect of liming on litter decomposing organisms is demonstrated with microorganisms, collembolae and earthworms regarding the abundance and the structure of dominance. It was shown that liming may induce unusually large changes in biocenoses of forest soils. The decay of surface humus accounted for 7.2 t ha-1 or 23% of the store within 7 years. Within the same time span, liming caused a loss of about 170 kg N ha-1 or 14% of the store of the surface humus layer. The nitrate concentration in the drainage water thus increased by about 50 to 60 mg NO3 - L-1. Site-specific conditions are discussed, which produce such negative liming effects as increased nitrate concentration of seepage, humus decay and heavy metal mobilization. Redistribution of tree roots, induction of boron deficiency and root rot are also considered. It is indicated that liming may aggravate the increasing problem of nitrate contamination of forest ground water resources which is associated with deposition of atmogenous nitrogen compounds. Some recommendations are given regarding forest practice.
Article
Landscapes are frequently seen as fragments of natural habitat surrounded by a 'sea' of agriculture. But recent ecological theory shows that the nature of these fragments is not nearly as important for conservation as is the nature of the matrix of agriculture that surrounds them. Local extinctions from conservation fragments are inevitable and must be balanced by migrations if massive extinction is to be avoided. High migration rates only occur in what the authors refer to as 'high quality' matrices, which are created by alternative agroecological techniques, as opposed to the industrial monocultural model of agriculture. The authors argue that the only way to promote such high quality matrices is to work with rural social movements. Their ideas are at odds with the major trends of some of the large conservation organizations that emphasize targeted land purchases of protected areas. They argue that recent advances in ecological research make such a general approach anachronistic and call, rather, for solidarity with the small farmers around the world who are currently struggling to attain food sovereignty. Nature's Matrix proposes a radically new approach to the conservation of biodiversity based on recent advances in the science of ecology plus political realities, particularly in the world's tropical regions. © Dr Ivette Perfecto, Dr John Vandermeer and Dr Angus Wright, 2009. All rights reserved.
Article
The uptake of 15N-labelled alanine, ammonium and nitrate was studied in ectomycorrhizal morphotypes of intact Pinus sylvestris seedlings. PCR-RFLP analysis of the ITS-region of fungal rDNA was used to identify the morphotypes. Seedlings were grown in forest soil collected at an experimental site in southern Sweden. The treatments compared were a control, N fertilisation (600 kg N ha-1 as urea), sulfur application (1200 kg S ha-1) and lime application (6000 kg CaCO3 ha-1). The forest, which had been dominated by Picea abies, was clear-cut two years before the forest soil was sampled. Soil was also collected from an adjacent standing forest. The aim of the present study was to detect changes in the ectomycorrhizal communities in forest soils and relate these changes to the functional parameter of uptake of nitrogen from organic (alanine and protein) and inorganic (ammonium and nitrate) sources. Liming resulted in the detection of a morphotype not found in other samples, and one morphotype was only found in samples from the standing forest (the fungi in these two morphotypes could not be identified). All mycorrhizal root tips showed a higher 15N concentration after exposure to different nitrogen forms than non-mycorrhizal long roots. Uptake of15 N from a labelled solution of alanine or ammonium was higher (about tenfold) than uptake from a 15N-labelled solution of nitrate. Uptake of ammonium and alanine varied between 0.2 and 0.5 mg N g-1 h-1 and between 0.1 and 0.33 mg N g-1 h-1, respectively, among the different morphotypes. In seedlings grown in the control soil and in soil from standing forest, alanine and ammonium were taken up to a similar degree from a supply solution by all morphotypes, whereas ammonium uptake was higher than alanine uptake in seedlings grown in lime-treated soil (about twofold) and, to a lesser extent, in the nitrogen- and sulfur-treated soils. The higher ammonium uptake by morphotypes from the limed soil was confirmed in pure culture studies. In cases where ammonium was used as the N source, an isolate of the S. variegatus morphotype collected in the limed soil produced more biomass compared with isolates of S. variegatus collected in nitrogen- or sulphur-treated soil. One isolate of a silvery white morphotype produced about equal amounts of biomass on alanine and ammonium, whereas all S. variegatus isolated performed better with ammonium as their N source. Based on the results it is hypothesised that liming can induce a shift in the ectomycorrhizal community, favouring individuals that mainly utilise inorganic nitrogen over those that primarily utilise organic nitrogen.