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Making soil biodiversity work for ecosystem goods and services
Lijbert Brussaard, Dept. of Soil QualityWageningen University, The Netherlands
Making soil biodiversity work for ecosystem
goods and services……..
…..is a challenge to
� scientists
� politicians
� practitioners
� Research and implementation programs rarely consider � Multiple scales� Tradeoffswhereas:
� Biodiversity-based management� Occurs at many scales� Produces outcomes at many
scales
Scale matters Globe
� Introduction� Soil biodiversity and the
greenhouse gas balance� Soil biodiversity for adaptive
agriculture under environmental change
� A landscape perspective on soils, climate change and biodiversity
� A learning network on “functional agrobiodiversity”
� Conclusions
OutlineGlobe
September 2008 issue (40 million readers)
Tim Kasten: “Get our messages right, speak with the same voice (IPCC), take that message to others, using communication experts”
Courtesy of Alfred Hartemink
Gabriele Broll: “Science communication is an academic discipline”
The soil provides key ecosystem goods and services
(Haygarth & Ritz, 2009, Land Use Pol 26S: S87)
Controlpests
Build soil structure
Remove pesticides and nutrients in buffer strips
Support plants viamutualism
Control and cycle plant nutrients
The soil biota contribute to ecosystem services in agricultural landscapes
Source/sink of GHG
Degrade pesticides in field
Break down wastes, make compost
Fix nitrogen
Build soil organic matter
Sequestercarbon
(http://images.google.com/imgres?imgurl=http://www.sare.org/publications/explore/images/scenewide2.jpg)
Courtesy of Kate Scow
Making soil biodiversity work for ecosystem
goods and services……..
…...is also a challenge to keeping:
� credibility in science� legitimacy with politicians and the public at large� salience with practitioners
Gabriele Broll: “Is high biodiversity best?”
(cf. Climategate – no Soilgate , please)
� Introduction� Soil biodiversity and the
greenhouse gas balance� Soil biodiversity for adaptive
agriculture under environmental change
� A landscape perspective on soils, climate change and biodiversity
� A learning network on “functional agrobiodiversity”
� Conclusions
OutlineGlobe
360
340
320
300
280
260
1000 20001200 1400 1600 1800
Year
CO
2 , ppm
CO2
270
310
250
290
N2O
, ppb
N2O
750
1000
1250
1500
1750
CH
4 , ppb
CH4
Greenhouse gas evolution over time
Afforestation and Reforestation
Conservation agriculture
Grassland restoration
Mitigating climate change using soilsMitigating climate change using soils
Biota560 Pg C
Soil OrganicMatter
1500 Pg C
Atmosphere750 Pg C
Ocean~38.000 Pg C
Extractablefossil fuels4000 Pg C
Potential CSequestration
50 Pg C
Sedimentaryrocks
~80.000.000 Pg C
Carbon pools: a global perspective
1 Pg = 1·1015 g
Philippe Ciais: “It is easier to keep the marbles in the jar than to tip them out and try to pick them up again” (quote from W.H. Schlesinger)
� 620,000 - 4,320,000 worms / hectare� Change soil structure and chemistry� Considered very beneficial to soil fertility
Soil biodiversity and the GHG balance:earthworms
Bulk soil
Earthwormburrows
Compacteddrilosphere soil
mineral particles
fresh litter
earthworm labile C inmacro aggregates
+
+
+ +
+
Earthworms enhance C storage
stable C inmicroaggregates
mineral particles
N2O N2O
++
but also N2O emissions
0
2
4
6
8
10
12
14
Soils Oceans Cattle (Fertilizer)industry
Atmosphere Biomassburning
N2O
flux
, Tg
N y
r-1Global sources of N2O emission
1 Tg = 1·1012 g
Tim Kasten: “Agriculture accounts for 30% of global GHG emissions”
Global warming potential
1 g N2O... equals 12 g CH4... equals 296 g CO2...
≈ ≈
Conclusions from research so far:
� Earthworms increase N2O emissions in any studied system
� The earthworm8induced N2O effect and observed interactions reflect the feeding ecologies of different species (earthworm diversity matters!)
� The tradeoff between elevated N2O emission and carbon sequestration remains to be determined
(Rizhiya et al., 2007, Soil Biol Biochem 39: 2058
Bertora et al., 2007, Soil Biol Biochem 40: 1999
Giannopoulos et al., 2010, Soil Biol Biochem 42: 618
Lubbers et al., 2010, Eur J Soil Sci (in press))
Earthworms have effect on:
� Soil structure� Soil organic matter dynamics
� Aggregation and porosity and N2O emissions
CO2 – carbon sequestration
� Water infiltration
biophysical process
earthworm activity
(After Le Bayon & Binet, 2001, Pedobiologia 45: 430)
Earthworm diversity matters
Epigeic Anecic Endogeic
50 cm
Soil management effects
N2O N2O
→ Less C storage→ Less N2O emissions?
→ Slow water infiltration
Conventional tillage
No-tillage
→ More C storage→ More N2O emissions?
→ Rapid water infiltration
Tim Kasten: “Reducing ecosystem degradation requires a lesson in economics: trade-offs and priorities to be made”
Matthias Drösler: “Global warming potential has to be calculated, not just carbon balance”
� Introduction� Soil biodiversity and the
greenhouse gas balance� Soil biodiversity for adaptive
agriculture under environmental change
� A landscape perspective on soils, climate change and biodiversity
� A learning network on “functional agrobiodiversity”
� Conclusions
OutlineGlobe
Environmental filters (biotic and abiotic)
Biodiversity
Trait diversity
(Modified after Lemanceau, Int Soc Microb Ecol J, submitted; courtesy of P Lemanceau)
Examples of traits � Plants
� Growth form
� Leaf/ root morphology
� Specific leaf area
� Root length density
� Canopy/ root system size and architecture
� Leaf/ root chemistry
� C concentration
� Nutrient concentration
� Root turnover
� (Soil) animals� Mouthparts morphology
� Feeding habit
� Mobility
� (Soil) microbes� Ecophysiology
(De Bello et al., 2010, Biodiv Cons 19: 2773)
(Ecosystem functions)
From understanding trait-based community assemblage in natural systems →
human-induced assemblageof trait-based communities in agriculture
Vandana Shiva: Forgotten foods
� Introduction� Soil biodiversity and the
greenhouse gas balance� Soil biodiversity for adaptive
agriculture under environmental change
� A landscape perspective on soils, environmental change and biodiversity
� A learning network on “functional agrobiodiversity”
� Conclusions
OutlineGlobe
Ecosystem services at the landscape level:
We need a landscape view to design ecology-based solutions, combining biodiversity with other renewable resources for adaptation to local ecosystem complexity and social frameworks under climate change
� Considers biodiversity –ecological functions in mosaics of crop production areas and natural habitats
� Sets sustainable management of biodiversity in a social-ecological framework
� Builds upon local experiences and participatory experimentation with diversified production systems
DIVERSITAS agroBIODIVERSITY network
8 research sites representing landscapes positioned along a biodiversity-productivity gradient
and a wide range of socio-economic conditionswww.agrobiodiversity-diversitas.org/
(Jackson et al., 2010, Curr Opinion Env Sci 2: 80)
Planning for ecology-based transformation in the face of (climate) change
Smaller scales:Enabling technologies usingknowledge embedded within the
systemsExamples:� mineral fertilizer, new varieties� models that optimize N
applications� irrigation systems� farm machinery
Larger scales:Transformational technologies for
knowledge-intensive systems
Examples:� conservation agriculture� models that improve breeding
programs� aerobic rice systems� precision farming
Enabling and transformational technologies
(After Keating et al., 2010, Crop Sci, 50: 109)
C sequestration management requires transitional technology
� Introduction� Soil biodiversity and the
greenhouse gas balance� Soil biodiversity for adaptive
agriculture under environmental change
� A landscape perspective on soils, climate change and biodiversity
� A learning network on “functional agrobiodiversity”
� Conclusions
OutlineGlobe
The ELNThe ELN--FAB conceptFAB concept
European Learning Network on Functional AgroBiodiversity
http://www.eln-fab.eu/
Problem definition
� Small scale, fragmented application of “functional”biodiversity (pollination, biocontrol, …)
� Perceived important contribution to sustainable agriculture
� Need for upscalingexperiences and practice
Mission of ELN-FAB
� Platform and facility for exchange of knowledge and practical experiences within EU member states, between farmers, policy makers, scientists, businesses and NGOs, in order to� enable fast and effective
implementation of best practices;� optimize agrobiodiversity benefits� promote sustainable agriculture
Tim Kasten: “Get our messages right, speak with the same voice (IPCC), take that message to others, using communication experts”
Not the whole story…
Vision of ELN-FAB
By 2030 the use of agrobiodiversity to
enhance ecosystem services is fully
integrated into European agricultural policies and practicesin a way that promotes sustainable agricultural
production
� Introduction� Soil biodiversity and the
greenhouse gas balance� Soil biodiversity for adaptive
agriculture under environmental change
� A landscape perspective on soils, climate change and biodiversity
� A learning network on “functional agrobiodiversity”
� Conclusions
OutlineGlobe
Concluding remarks
� There are tradeoffs and synergies between biodiversity-based ecosystem services (example: GHG balance) ―scientists have to inform politicians and practitioners, so they can make well-founded decisions
� Ecology increasingly provides the tools for biodiversity-based production of agricultural goods and ecosystem services
� A landscape perspective on soils, (climate) change and biodiversity, including stakeholder interactions, is necessary (and possible)
� Co-learning of scientists with practitioners is needed in applying “functional” (agro)biodiversity at the landscape scale
Gabriele Broll: “Soil is simple and decomposition is easy to understand!”
Acknowledgements:Ingrid Lubbers, Wageningen, NLJan-Willem van Groenigen, Wageningen, NLMembers of DIVERSITAS’ agroBIODIVERSITY networkMembers of the European Learning Network on Functional
AgroBiodiversity
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