1 research outputs found
Understanding variation in salamander ionomes: A nutrient balance approach
Ecological stoichiometry uses information on a few key biological elements (C, N, and P) to
explain complex ecological patterns. Although factors driving variation in these elements are
well-established, expanding stoichiometric principles to explore dynamics of the many other
essential elements comprising biological tissues (i.e., the ionome) is needed to determine their
metabolic relationships and better understand biological control of elemental flows through
ecosystems.
2. In this paper, we report observations of ionomic variation in two species of salamander
(Ambystoma opacum and A. talpoideum) across ontogenic stages using specimens from
biological collections of two wetlands sampled over a 30-year period. This unique data set
allowed us to explore the extent of ionomic variation between species, among ontogenic stages,
between sites, and through time.
3. We found species- and to a lesser extent site-specific differences in C, N, and P along with 13
other elements forming salamander ionomes but saw no evidence of temporal changes.
Salamander ionomic composition was most strongly related to ontogeny with relatively higher
concentrations of many elements in adult males (i.e., Ca, P, S, Mg, Zn, and Cu) compared to
metamorphic juveniles, which had greater amounts of C, Fe, and Mn.
4. In addition to patterns of individual elements, covariance among elements was used to
construct multi-elemental nutrient balances, which revealed differences in salamander elemental
composition between species and sites and changes in elemental proportions across ontogenic
development. These multi-elemental balances distinguished among species-site-ontogenic stage
groups better than using only C, N, and P.
5. Overall, this study highlights the responsiveness of consumer ionomes to life-history and
environmental variation while reflecting underlying relationships among elements tied to
biological function. As such, ionomic studies can provide important insights into factors shaping
consumer elemental composition and for predicting how these changes might affect higher-order
ecological processes