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Automated, High-resolution Mobile Collection System for the Nitrogen Isotopic Analysis of NOx
Published on: December 20, 2016
Fertilizer nitrogen isotope signatures.
Alison S Bateman1, Simon D Kelly
1School of Environmental Sciences, University of East Anglia, Norwich NR4 7TJ, UK.
Isotopes in Environmental and Health Studies
|September 6, 2007
Summary
Nitrogen isotope analysis can distinguish organic from conventional crops. Organic fertilizers show significantly higher delta15N values than synthetic ones, enabling this differentiation.
Area of Science:
- Agricultural Science
- Environmental Science
- Analytical Chemistry
Background:
- Nitrogen isotope analysis is a promising tool for differentiating crop origins.
- A key factor is the distinct nitrogen isotope composition of fertilizers used in organic and conventional farming.
Purpose of the Study:
- To measure and compile nitrogen-15 (delta15N) values for synthetic and organic fertilizers.
- To assess the potential of nitrogen isotope analysis for distinguishing organically from conventionally grown crops.
Main Methods:
- New measurements of delta15N values for synthetic nitrogen fertilizers.
- Compilation of new and existing literature data on nitrogen isotope values.
- Analysis of delta15N values for fertilizers permitted in organic cultivation.
Main Results:
- Synthetic fertilizers have delta15N values close to 0‰ (mean 0.2‰, 98.5% < 4‰).
- Organic fertilizers exhibit a broader range with a higher mean delta15N value of 8.5‰ (0.6‰ to 36.7‰).
Conclusions:
- Distinct nitrogen isotope signatures of fertilizers support the potential for crop origin discrimination.
- Further research should consider other factors influencing crop delta15N values.
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