"The ecological cost of doing agricultural business: Tradeoffs in the Amazon between agricultural production and ecosystem functioning" Presented at the University of Minnesota, 2 Oct 2013, as a pre-thesis public seminar and as a portion of my preliminary oral PhD exam.

1. The cost of doing business
ecological
agricultural
>
>
Christine S. O’Connell
Pre-Thesis Seminar
2 October 2013

2. Amazon rundown:
Background
Key questions

3. The Amazon is an
Enormous gear 1

4. Amazonia’s biomass stores
100 billion tonnes of carbon
Saatchi et al. (2007)

5. of precipitation in
Amazonia is returned to
the atmosphere by plants.
60%
Brienen et al. (2012)

6. This plant evapotranspiration balances
excess solar energy
West et al. (2011)

7. West et al. (2011)
High
net
energy
Most of it lost via plantspumping water, notthrough surface heating

8. Whirlwind on deforested land,
Mato Grosso, BRA

9. Human use is rapid
and changing 2

10. of the Amazon is
deforested
17%
Nepstad et al. (1999)

11. …much of that for agricultural
export commodities
DeFries et al. (2013), MacDonald et al. in prep

12. Brazilian
soybean
yields rose
by 50% from
1990 to 2008
Ray et al. (2013)

13. And head of cattle in
the Brazilian Amazon
rose by 100%
Instituto Brasileiro de Geografia e Estatística (2008)

14. There is no one
Amazon ecology 3

15. Let’s take a quick tour of the Amazon…
- Total biomass
~= 130 MgC/ha
- NPP disputed,
possibly ~= 7
MgC/ha/yr
- Tree diversity as
Fisher’s α ~= 60
- Total biomass
~= 175 MgC/ha
- NPP ~= 10
MgC/ha/yr
- Tree diversity as
Fisher’s α ~= 200
Saatchi et al. (2011), Aragao et al. (2009), Del
Grosso et al. (2008), Ter Steege et al. (2003)
NPP = net primary productivity;
LULCC = land-use/land-cover change

16. Let’s take a quick tour of the Amazon…
- Total biomass
~= 130 MgC/ha
- NPP disputed,
possibly ~= 7
MgC/ha/yr
- Tree diversity as
Fisher’s α ~= 60
- Total biomass
~= 175 MgC/ha
- NPP ~= 10
MgC/ha/yr
- Tree diversity as
Fisher’s α ~= 200
Monfreda et al. (2008), Aragao et al. (2009), Del
Grosso et al. (2008), Ter Steege et al. (2003)
- Total biomass
~= 175 MgC/ha
- NPP ~= 10
MgC/ha/yr
- Tree diversity as
Fisher’s α ~= 200
- Low amounts of
LULCC
- Total biomass
~= 130 MgC/ha
- NPP disputed,
possibly ~= 7
MgC/ha/yr
- Tree diversity as
Fisher’s α ~= 60
- High amounts of
LULCC
NPP = net primary productivity;
LULCC = land-use/land-cover change

17. Amazon rundown:
Background
Key questions

18. The
Big Gap

19. How will Amazonia’s role in the earth
system be affected by human use?
And What are the Tradeoffs?

20. Tradeoffs, here, compare the ecological losses to
the agricultural gains from LULCC

21. Tradeoffs, here, compare the ecological losses to
the agricultural gains from LULCC
A similar
calculation yields:
3/125
= 24*10-3 Mg soy
gained/Mg C lost/
ha (30% more ag
per unit C lost)
Modeled ag gains
Soybean fields yield
3.1 Mg/ha
Modeled C losses
Forest à ag
transition loses 170
MgC/ha
Ex. Ag/C Tradeoff
3.1/170
= 18*10-3 Mg soy
gained/Mg C lost/ha
Monfreda et al. (2008), O’Connell et al. in prep

22. Q What are the tradeoffs to
extensified
(expanding) agriculture?

23. Q
FIRST:
How do different
ecological tradeoffs vary
across space?

24. We combined data from remote
sensing, model output, and
geostatistical datasets to assess
spatial tradeoff variation
• Changes in carbon (C) stocks
• Energy balance regulation
• Habitat quality
• Agricultural productivity

25. O’Connell et al. in prep
C stock reductions relate to precip and flooding

26. Local drying post-LULCC is greater in the seasonal E
O’Connell et al. in prep

27. O’Connell et al. in prep
…and local warming is higher in the same area

28. All 3 taxa sets have highest diversity in the Andes
O’Connell et al. in prep

29. O’Connell et al. in prep
Tradeoffs consider both gains and losses
Calories gained / change
in ecosystem property

30. Climate Reg; Habitat; C Stock
O’Connell et al. in prep

31. The tradeoffs of agricultural extensification
depend on which environmental variable
is being prioritized and the biophysical
regional context.

32. Q
SECOND:
How do future LULC
scenarios compare to an
Amazonia managed for
tradeoff efficiency?

33. Estimate calories
produced in
2050 from a
projected LULC
arrangement
Step 1
Step 2
Solve for LULC in
Amazonia that
produces the same
number of calories at
least cost to
ecological functioning
Soares-Filho et al. (2006)

34. Expected Results
Business-As-Usual
Optimized
MeanReductioninBiomass
CarbonStocks/ha
Effects on C stocks to produce
XX agricultural output
Same agricultural
output with a lower
ecological impact
when managing fortradeoffs

35. Amazon rundown:
Background
Key questions

36. Q What are the tradeoffs to
intensified
(industrial) agriculture?

37. Q
FIRST:
How is intensified
agriculture changing
nitrous oxide (N2O)
emissions?

38. N2O,
nitrous oxide, is a
greenhouse gas with
300 times the warming
potential of CO2.
• Emitted by multiple distributed
microbial processes
• Regulated by temp, pH, H2O, and
availability of oxygen, organic carbon,
labile nitrogen
• Intensified agricultural management
alters N availability – now in Amazonia

39. • Baseline forest
Extractable N pools: ~4-5
mg N/kg dry soil
• Soybean cropland
N inputs: N-fixing crop
(~170 kg N/ha), lower C
and H2O
• Soy/maize double
cropping
N inputs: N fertilizer
addition (~60 kg N/ha),
lower C and H2O
Treatments vary by
LULC

40. Field measurement of N pools and fluxes
designed to quantify spatial and temporal variation

41. J
F
M
A
M
J
J
A
S
O
N
D
(--------2014--------)
(--------------2013--------------)
Forest (control) Highest
Soy/Maize Middle
Soy Lowest
J
F
M
A
M
J
J
A
S
O
N
D
(--------2014--------)
(--------------2013--------------)
Annual N2O
Emissions
Forest (control) Middle
Soy/Maize Highest
Soy Lowest
Annual N2O
Emissions
Expected Results
N2Ofluxes
(μgNm−2hr−1)
N2Ofluxes
(μgNm−2hr−1)

42. Intensifying Amazonian croplands via double
cropping with N fertilizer is a novel land use with
poorly understood N2O emissions
consequences.

43. Q
SECOND:
How are N2O emissions
from intensification
affecting the regional
GHG budget?

44. From Galford et al. (2010)
Work with
collaborators to
quantify LULC trend
Step 1
Use field results with
a process-based
model to correct for
abiotic factors
Step 2
Step 3
Scale across region

45. Intensification in eastern Amazonia yields double
the agricultural production.
But perhaps at an ecological cost of rising
greenhouse gas emissions
…a tradeoff specific to intensified agriculture.

46. Q
What do the ecological
tradeoffs of agriculture
imply for governance and
policy?

47. Thanks very much
Photo credits
Flickr CC Users
CIFOR
Billtacular
Jacsonquerubin
flinner!
Carine06
LeoFFreitas
terrydu
ggallice
Icelight
MODIS images via NASA
Obrigada to
The Foley, Polasky, Powers and
Hobbie lab groups
BCE: Aaron, Charlotte, Jane,
Kristen, Tricia
Supporting agencies, institutions
and collaborators below,
especially the IPAM field team
Friends and family
Christine S. O’Connell, coconn@umn.edu, UMN EEB/IonE

49. Backup slides

50. Intensified agricultural management is
changing N availability via fertilizer use
…increasingly now in the Amazon

51. • Baseline forest
Extractable N pools:
~4-5 mg N/kg dry soil
Organic C: rel. high
Soil moisture: rel. high
N inputs: N-fixing tree
species
• Soybean cropland
• Soy/maize double
cropping
Treatments vary by
LULC

52. • Baseline forest
• Soybean cropland
Extractable N pools: rel.
lower?
Organic C: rel. lower
Soil moisture: rel. lower
N inputs: N-fixing crop
(~170 kg N/ha)
• Soy/maize double
cropping
Treatments vary by
LULC

53. • Baseline forest
• Soybean cropland
• Soy/maize double
cropping
Extractable N pools: rel.
lower?
Organic C: rel. lower
Soil moisture: re. lower
N inputs: N fertilizer
addition (~60 kg N/ha)
Treatments vary by
LULC

54. West et al. (2011)
High
net
energy
Most of it lost via plantspumping water, notthrough surface heating

55. Deforestation has become uncoupled from commodity
production in some portions of the Brazilian Amazon
Macedo et al. (2012)

56. Supplemental
Table
2:
Current
harvested
area
and
quan6ty
produced
for
key
crops
in
Brazil
and
the
Brazilian
Legal
Amazon
(data:
IGBE).
Key
crops
here
are
Brazil’s
top
ten
crops
by
harvested
area
(2009-­‐11
average)
and
banana
and
tomato,
which
are
in
Brazil’s
top
ten
crops
by
produc6on
(2009-­‐2011
average).
O’Connell et al. in prep

57. Macedo et al. (2012), INPE
Annual deforestation, Brazilian AmazonAreadeforested(km2)
Peaked in
the
mid-2000s

58. 0
50000
100000
150000
200000
250000
Amazon
Next Six Largest Rivers
AverageDischarge(m3/s)
Amazon
Ganges
Congo
Orinoco
Yangtze
Parana
Yenisei
209,000 m3/s
The water flow out of the Amazon
River is greater than the world’s next
six largest rivers combined
191,000 m3/s
(total)

59. Agricultural yield, main text

60. Biodiv taxa maps, supplemental fig

61. Climate reg, supplemental fig
Net
Radia)on
Latent
Heat
Flux
Sensible
Heat
Flux
Natural
Vegeta)on
Soybean
Grass
0 20 40 60 80 100 120 140
W·m-2
0 20 40 60 80 100 120 140
W·m-2
Degrees Celsius
0
1.3
2.7
4.0
5.3
6.7
8.0
9.3
0 20 40 60 80 100 120 140
W·m-2
mm H2O
0
0.8
1.5
2.3
3.1
3.8
4.6
5.4

62. Climate reg, supplemental fig
-30 -20 -10 0 10 20 30
W·m-2
mm H2O
-1.1 -0.8 -0.4 0 0.4 0.8 1.1
-30 -20 -10 0 10 20 30
W·m-2
Degrees Celsius
-2.0 -1.3 -0.7 0 0.7 1.3 2.0
-35 -30 -25 -20 -15 -10 -5 0
W·m-2
mm H2O
-1.3 -1.1 -1.0 -0.8 -0.6 -0.4 -0.2 0
-35 -30 -25 -20 -15 -10 -5 0
W·m-2
Degrees Celsius
-2.3 -2.0 -1.7 -1.3 -1.0 -0.7 -0.3 0

63. We combined data from remote
sensing, model output, and
geostatistical datasets to assess
tradeoff variation across space
Carbon stock
Combined satellite data and land-use
information
Regional
climate
Process-based model runs
Habitat quality
Statistical species range models
Agricultural
production
Regression models using public
agricultural data

64. Chapin, Matson, Vitousek (2011)

65. Venterea et al. (2012)

66. Venterea et al. (2012)

68. We are limited by
ideas, not by tools
- Peter Groffman