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Nitrogen Deposition Effects of Ammonia Ammonia Workshop
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tarix | 28.07.2018 | ölçüsü | 2,33 Mb. | | #59385 |
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Ammonia Workshop National Atmospheric Deposition Program October 22-24, 2003 Washington, DC USA
Contrasting NOx and NH3 Historical focus on NOx Growing focus on NH3 Similarities - Both have point and mobile sources
- Both, once emitted can be converted to any other N species
Both contribute to all the N-related impacts.
Reactive N vs Unreactive N2 Unreactive N is N2 (78% of earth’s atmosphere) Reactive N (Nr) includes all biologically, chemically and physically active N compounds in the atmosphere and biosphere of the Earth
Reactive N vs Unreactive N2 Unreactive N is N2 (78% of earth’s atmosphere) Reactive N (Nr) includes all biologically, chemically and physically active N compounds in the atmosphere and biosphere of the Earth N controls productivity of most natural ecosystems Nature converts N2 to Nr by biological nitrogen fixation (BNF). Humans convert N2 to Nr by fossil fuel combustion, the Haber Bosch process, and cultivation-induced BNF.
Reactive N vs Unreactive N2 Unreactive N is N2 (78% of earth’s atmosphere) Reactive N (Nr) includes all biologically, chemically and physically active N compounds in the atmosphere and biosphere of the Earth N controls productivity of most natural ecosystems Nature converts N2 to Nr by biological nitrogen fixation (BNF) Humans convert N2 to Nr by fossil fuel combustion, the Haber Bosch process, and cultivation-induced BNF. Primary Conclusions - Humans create more Nr than do natural terrestrial processes.
- Nr is accumulating in the environment.
- Nr accumulation contributes to most environment issues of the day.
- NHx and its conversion products are key components.
Objectives Contrasting NOx and NH3 Human Alteration of N Cycle - An agrarian to an industrializing world
The Consequences of Anthropogenic Nitrogen (including NH3). - Nitrogen is nutritious
- Nitrogen cascades
Challenges!
The History of Nitrogen --N becomes limiting?--
The History of Nitrogen --Nr Creation, Haber Bosch process--
The History of Nitrogen --Nr Creation: Fossil Fuel Combustion--
The History of Nitrogen --Nr Creation, People and Nature--
Nitrogen Drivers in 1860
Nitrogen Drivers in 1860 & 1995
Nitrogen Deposition Past and Present mg N/m2/yr
Nr and Agricultural Ecosystems Haber-Bosch has facilitated agricultural intensification 40% of world’s population is alive because of it An additional 3 billion people by 2050 will be sustained by it Most N that enters agroecosystems is released to the environment.
Nr and the Atmosphere NOx emissions contribute to OH, which defines the oxidizing capacity of the atmosphere NOx emissions are responsible for tens of thousands of excess-deaths per year in the United States O3 and N2O contribute to atmospheric warming N2O emissions contribute to stratospheric O3 depletion
Nr and Terrestrial Ecosystems N is the limiting nutrient in most temperate and polar ecosystems Nr deposition increases and then decreases forest and grassland productivity Nr additions probably decrease biodiversity across the entire range of deposition
Nr and Freshwater Ecosystems - Tens of thousands of lakes and streams
- Biodiversity losses
As reductions in SO2 emissions continue, Nr deposition becomes more important.
Nr and Coastal Ecosystems
Hog Production in USA (1 dot= 10,000 Hogs and Pigs)
Meat Consumption in North America (kg/capita/year)
Conclusions NH3 contributes to every N-related issue Nr and NHx are accumulating in environmental reservoirs The impacts of N accumulation are significant and inter-related NH3 emissions will increase with time There is need for an integrated approach to manage N!
Meat Consumption in North America (kg/capita/year)
Nr Creation Rates by Food and Energy Production in 2050
Nr Creation Rates 1995 (left) and 2050 (right) TgN/yr
Nr Creation Rates 1995 (left) and 2050 (right) TgN/yr
The Fate of Haber-Bosch Nitrogen
The Fate of Haber-Bosch Nitrogen
The Fate of Haber-Bosch Nitrogen
Nr Riverine Fluxes 1860 (left) and 1990 (right) TgN/yr
Nr Formation vs. Nr Conversion back to N2
Nr Formation vs. Nr Conversion back to N2
Nr Formation vs. Nr Conversion back to N2
International Nitrogen Initiative Formed in December 2002; SCOPE & IGBP sponsors Objective - optimize nitrogen’s beneficial role in sustainable food production and minimize nitrogen’s negative effects on human health and the environment resulting from food and energy production.
Preliminary assessment in December 2004.
The Components of INI
The Components of INI
Phase I: Assessment of Science and Identification of Problems
Phase I: Assessment of Science and Identification of Problems
Phase I: Assessment of Science and Identification of Problems
Phase I: Assessment of Science and Identification of Problems
Phase II: Development of Solutions Phase III: Implementation of Solutions
International Nitrogen Initiative Current Status - Formed in December 2002
- Sponsored by SCOPE and IGBP
- INI has a 15-person Scientific Advisory Committee
- members from Brazil, China, France, Netherlands, Japan, South Africa, Sweden, Thailand,Uganda, United Kingdom, United States
- First SAC meeting is hosted by Dutch Government
- May 12-14, 2003, The Hague
The Challenge to all Parties Maximize food and energy production while maintaining environmental and human health!
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