Global estimates of gaseous emissions of NH₃, NO and N₂O from agricultural land

INTERNATIONAL FERTILIZER INDUSTRY ASSOCIATION
Food and Agriculture Organization of the United Nations
Rome, 2001

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ISBN 92-5-104698-1

© FAO, 2001

Contents

Acknowledgements

Chapter 1. Introduction

Chapter 2. Regulating factors

Factors regulating nitrous oxide and nitric oxide emission

Controls of denitrification, nitrification and N oxide fluxes

N availability

Nitrification and denitrification rates

Soil moisture and temperature

Gas diffusion

Agricultural management factors

Fertilizer management

Soil and crop management

Factors regulating ammonia loss

Chapter 3. Measurement techniques

Chamber techniques

Micrometeorological techniques

Indirect open measurement technique

¹⁵N, n balance and n difference methods

Chapter 4. Measurements

Nitrous oxide, denitrification and nitric oxide measurements

Fertilizer induced emissions

Nitrous oxide

Analysis of regulating factors of nitrous oxide and nitric oxide emissions

Data handling

Data interpretation for nitrous oxide emissions

Data interpretation for nitric oxide emissions

Summary of ammonia volatilization measurements

Anhydrous ammonia

Ammonium bicarbonate

Ammonium nitrate

Ammonium sulphate

Calcium ammonium nitrate

Calcium nitrate

Diammonium phosphate

Monoammonium phosphate

Urea ammonium nitrate

Flooded systems

Ammonium bicarbonate

Ammonium sulphate

Summary of regulating factors of ammonia volatilization

Data handling

Data interpretation for ammonia volatilization

Chapter 5. Global estimates

Data on land use, fertilizer management and environment

Extrapolation for nitrous oxide and nitric oxide

Extrapolation for ammonia

Chapter 6. Conclusions

Nitrous oxide and nitric oxide emissions

Ammonia volatilization

Annex 2: Tables

TABLE 1.
Global sources of atmospheric NO_x, NH₃ and N₂O, 1990

TABLE 2.
Information collected for measurements

TABLE 3.
Measurement technique codes

TABLE 4.
Fertilizer induced N₂O emission, % calculated directly from the data set

TABLE 5.
Fertilizer induced NO emission (%) and the NO/N₂O ratio, calculated directly from the data set

TABLE 6.
Climate codes

TABLE 7.
Values of constants and factor classes in the models for N₂O and NO

TABLE 8.
NH₃ volatilization rates for various factors

TABLE 9.
Factor values in the linear regression model

TABLE 10.
N₂O and NO emission estimates from N fertilizer and animal manure application on crops, 1995

TABLE 11. N₂O and NO emission from N fertilizer and animal manure application on grasslands, 1995

TABLE 12.
Global N use and fertilizer induced N₂O and NO emission estimates by fertilizer type

TABLE 13.
NH₃ volatilization loss estimates from mineral N application on fertilized grasslands, upland crops and wetland rice by region, 1995

TABLE 14.
NH₃ volatilization loss estimates from animal manure application on intensively used grasslands, upland crops and wetland rice by region, 1995

TABLE 15.
NH₃ volatilization loss rates for mineral fertilizer category and for animal manure, 1995

TABLE 16.
N₂O emissions from the data set (kg N₂O-N/year/ha)

TABLE 17.
NO emissions from the data set (kg NO-N/year/ha)

LIST OF FIGURES

1. The nitrogen cycle

2. Fertilizer N application and nitrous oxide emission

3. Relation between fertilizer N application and nitric oxide emission