Tools for Analysis
Stable isotopes are a powerful tool in environmental research. However, isotopic patterns are caused by contributions from many potential pathways of addition and loss. Accordingly, making predictions of isotopic patterns based on analytical or quantitative models of isotope fluxes is increasingly important to improving our ability to understand the natural world from isotopic patterns. Here, we provide links to papers or other websites that use isotopic models to interpret isotopic patterns. Links included below address partitioning dietary components from multiple isotopic data, calculating water flux patterns in vegetation, and interpreting nitrogen isotope patterns in plants from information on symbiotic fungi and inorganic nitrogen availability, as well as links to a generic isotopic model easily adaptable to existing ecosystem models.
Relevant Links and Resources:
- http://www.eeb.cornell.edu/isogeochem/
A general clearinghouse for isotope geochemistry information, and home page of the ISOGEOCHEM list server.
- http://www.waterisotopes.org/
Information, data, and resources for scientific applications involving spatial variation in the isotopes of hydrogen and oxygen.
- http://ecophys.biology.utah.edu/Research/Isoscapes/models.html
Modeling leaf water hydrogen and oxygen isotopes in arcGIS.
- http://www.epa.gov/wed/pages/models/stableIsotopes/isotopes.htm
- http://www.epa.gov/wed/pages/models/stableIsotopes/isosource/isosource.htm
IsoError: Confidence interval calculation for source partitioning using stable isotopes
IsoConc: Concentration-dependent stable isotope mixing model
IsoSource: stable isotope mixing model for partitioning an excess number of sources - http://ecosystems.mbl.edu/Research/Models/nesis/welcome.html
NESIS (non-equilibrium stable isotope simulator) takes output from ecosystem models and after addition of appropriate fractionation factors for fluxes will predict isotopic signatures for ecosystem pools.
- Roden & Ehleringer (2000). Hydrogen and oxygen isotope ratios of tree ring cellulose for field-grown riparian trees. Oecologia 123: 481-489.
A model for estimating oxygen and hydrogen water fluxes to plant cellulose from isotopic measurements.
- More working hypotheses from the Hobbie Laboratory.