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Cost of nitrogen use in the US Jana Compton, US EPA ORD NHEERL WED Corvallis Oregon

Dan Sobota, Oregon Dept. of Environmental QualityMichelle McCrackin, Stockholm University

Shweta Singh, University of TorontoEPA’s Sustainable & Healthy Communities Research Program

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Compton et al. 2011 Ecology Letters

Nitrogen (N) inputs to US increased 5-fold since 1900

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Where are the largest human inputs?

Sobota et al. 2013, FIEE

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Dominant Human N Source

Sobota et al., 2013, Frontiers in Ecology and the Environment

8-digit USGS Hydrologic Unit Codes

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What happens to the N inputs?

External63%

Houlton et al. 2012, Biogeochemistry

Multiple costs of reactive N

Modified from Galloway et al. (2003) and Compton et al. (2011)

Air

Land

Water

Consumption

Agriculture

Energy

Ozoneeffects

Groundwatereffects

ParticulateMatter effects

Stratosphericeffects

N2OAir

Surface watereffects

Oceaneffects

NH3

Soil

PlantAgroecosystemeffects

Soil

Crop Animal

Forests &Grasslands

effects

Coastaleffects

NHxNOyNOx

Greenhouseeffects

N2O

NHxNOy

N2O(aquatic)

Land

Water

Brazosports

NO3-

HealthyLakes.org

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Our approach

• Trace N fate through the cascade– Source: Fossil fuel combustion,

agriculture, sewage– Impacts: human health/social,

ecosystems, agriculture, climate• Combine N flux data with

compiled data on N costs• $/kg N (Compton et al. 2011; Birch et al.

2011; van Grinsven et al. 2013)

NASA

www.ovivowater.com

Drinking water contamination

Health effects of smog

Damages from eutrophication

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Costs of nitrogen pollution

Human respiratory health

Freshwater eutrophication

Damage to seagrass and fisheries

Low and high values are associated with the EU N Assessment (Van Grinsven et al. 2013 ES&T).

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Damages from source

Source/SectorDamage cost (billion USD)

Agriculture $157.1 Fossil fuel $50.2 Sewage $2.3

Total damages from NRange

$209.6 $81-441

kg N ha-1 yr-1

0 - 1

1 - 3

3 - 5

5 - 10

10 - 3

0

30 - 5

0

50 - 9

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Anthropogenic N leakage to the environment, circa 2000

Sobota et al., in review

0 500 1,000 km

~1800 km2 watershed units(8 digit Hydrologic Unit Codes)

N

Freshwater damage costs, circa 2000

0 500 1,000 km

~1800 km2 watershed units(8 digit Hydrologic Unit Codes)

$ ha-1 yr-1

2 - 10

10 - 5

0

50 - 1

00

100 -

500

500 -

1000

1000

- 195

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Sobota et al., 2015

N

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Other damage estimates

• Cost of N impacts in the EU27, 2008 – $97-625 billion USD (Van Grinsven et al. 2013)

• Gross annual damages from NOx and NH3, 2002 – $16 billion USD (Muller and Mendelsohn 2007)

• Increased mortality associated with NH3-derived PM2.5 from food export, 2006– $36 billion USD (Paulot & Jacob 2013 ES&T)

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Summary

• Human activities have increased N fixation by 5-fold. 65% goes to agriculture.

• 71% of N leaked ends up in water resources.

• Nitrogen damage costs are substantial.

• Better quantify costs, particularly for Harmful Algal Blooms and drinking water.

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For more information Jana Compton compton.jana@epa.gov

Also see: EPA SAB Integrated nitrogen committee report 2011EU Nitrogen Assessment 2011International Nitrogen Initiative website