Chapter 8 Problems
1. True or False: At the present time, lasers can measure isotope compositions of
trace gases such as CO2 and so can provide an isotope scanner for some types of
field ecology.
2. True or False: Currently most stable isotope measurements are made with mass
spectrometers because these machines are 10-100x more accurate and precise than
laser-based systems.
3. True or False: Most mass spectrometer systems require little sample preparation
and can vaporize samples and measure isotopes of all the HCNOS elements in a
sample within a two-minute scan.
4. True or False: Stable isotopes can be used in multivariate analyses of niche space.
5. True or False: In the case of mangrove biology described in section 8.2, stable
isotopes were the best markers for separating different species.
6. True or False: The causes of isotope variation in plants are extremely well-known,
so that once you have measured isotope data for plants, it is very easy to infer
their in situ physiology and sources of nutrients.
7. True or False: Stable isotope values often reflect a combination of source and
processing (fractionation) information, and it takes some thought, skill and often
experimentation to understand whether source or fractionation information
dominates the measured isotope values.
8. True or False: Imagination is all it takes to be successful in science, or at least
successful in stable isotope ecology.