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Forests in the Balance: Forests as Providers of Ecosystem Services vs. Emissions from

Deforestation and Forest Degradation

Daniel NepstadChief Program Officer, Environmental Conservation Program

June 18, 2009

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4Forests inhale and exhale on an annual cycle

5Forest carbon stocks leaking into the atmosphere: deforestation

Houghton et al. 2007;

Page et al. 2003;

Alencar et al. 2006

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~half of Amazon forests depend upon deep root systems (>8 m) to remain physiologically active during seasonal drought, supplying

the atmosphere with water vaporNepstad et al. 1994 Nature

8A drought threshold experiment: 2000-2005

Nepstad, et al. 2007 Ecology

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The drought threshold:

• Large canopy trees are most vulnerable to drought

• Lianas and trees more vulnerable than palms

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Nepstad et al. 2007

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Value of forests to nearby coffee farms

Coffee near forest (within 1 km):

• 2x more bee visits

• 5x more bee species

• 20% higher yields

Lowerbound value of forest:

• $60,000/year (7% of farm revenue)

• Equivalent to competing land uses

$

$

Ricketts et al. 2004. PNAS 

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Forest dieback has begun

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18Amazon 2030: 55% cleared or degraded; 15-25 B tons C emitted

Nepstad et al. 2008 Phil Trans Roy Soc

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Nepstad et al. 2006 Cons Biol

20REDD alone is not enough. The world needs more food

Area of Cattle & Sugar Cane, Brazil

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Cattle Pasture 2006 Sugar Cane 2006 Sugar Cane 2020

Mill

ions

of H

ecta

res

21A 20-year land agenda

Could we reduce carbon emissions from land by 3 B tons per year in two decades?

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DeforestationNew ForestsSoil CarbonNet Flux

2010 2020 2030 2040 2050Carb

on e

mis

sions

from

the land

(Bill

ions

of

Tons

per

Year)

Year

3 B ton reduction by 2020