Predicting Inter‐Taxa Differences in Plant Uptake of Cesium‐134/137

Abstract

For (134/137)Cs, and many other soil contaminants, research into transfer to plants has focused on particular crops and phytoremediation candidates, producing uptake data for a small proportion of all plant taxa. Despite the significance of differences in uptake between plant taxa, the capacity of soil-to-plant transfer models to predict them is currently confined to those taxa for which data exist, there being no method to predict uptake by other taxa. We used residual maximum likelihood (REML) analysis on data from experiments (including 89 plant taxa from China plus 32 phytoremediation candidates) together with data from the literature, to construct a database of relative (134/137)Cs concentrations in 273 plant taxa. The REML (134/137)Cs concentrations in plants are not normally distributed but significantly clustered. Analysis of variance (ANOVA), coded with a recent ordinal phylogeny for flowering plants, showed that plant taxa do not behave independently for (134/137)Cs concentration because 42 and 15% of inter-taxa differences are associated with phylogeny above the species and ordinal level, respectively. In general, Eudicots, and especially the Caryophyllales, Asterales, and Brassicales, have high (134/137)Cs concentrations, while the Fabales and Magnoliids, in particular Poales, have low (134/137)Cs concentrations. Plants of the stress-tolerant ruderal (S-R) growth strategy sensu Grime have, in general, high concentrations of Cs, while those of the competitive (C) and generalist (C-S-R) strategies have low concentrations, although these effects are less pronounced than those of phylogeny. Plant phylogeny and growth strategy might thus be used to predict a significant portion of inter-taxa differences in plant uptake of (134/137)Cs.

Inter-taxa differences in root uptake of 103/106Ru by plants

“…Relative mean concentrations for these higher taxa do not necessarily ensure that all species within them have low or high values but rather there are significant tendencies to low or high values. In comparison to other studies of ion concentrations in plants down to the Ordinal level, the phylogenetic signal for Ru of 39% is greater than that for P (6.8%) and N (3.3%) (Broadley et al, 2004), Cs (15%) (Willey et al, 2005), Pb (20%), Cr (23%), Cu (24%), and Cd (27%) (Broadley et al, 2001), and Na (23%) (Broadley et al, 2004), but less than that for Zn (44%), Ni (46%) (Broadley et al, 2001), K (49%) (Broadley et al, 2004) and Ca (63%) (Broadley et al, 2003).…”

“…Soltis et al, 1999). Treating relative elemental concentration as a phenotype and mapping it to the flowering plant phylogeny have revealed significant phylogenetic effects on the relative concentration in plants of 137 Cs (Broadley et al, 1999;Willey et al, 2005), Cu, Zn, Ni, Cd and Pb, (Broadley et al, 2001), Ca (Broadley et al, 2003) and Mg, K, N, and P (Broadley et al, 2004). These studies reveal that, with the exception of N and P, at least some of the inter-species differences in relative concentration can be ascribed to taxonomic levels higher than the species.…”

A phylogenetic effect on strontium concentrations in angiosperms

“…In comparison to other studies of ion concentrations in plants down to the ordinal level, the phylogenetic effect for Sr of 14.5% is greater than that for P (6.8%) and N (3.3%) , similar to that for Cs (15%) (Willey et al, 2005) approaching that for Pb (20%), Cr (23%), Cu (24%), Cd (27%) (Broadley et al, 2001) and Na (23%) , but significantly less than that for Zn (44%), Ni (46%) (Broadley et al, 2001), Ca (63%) and K (49%) . For Sr there are significant differences in mean relative concentration between non-Eudicots and Eudicots (Figs.…”

“…Not only have phylogenetic effects been described in plant phenotypes such as photosynthetic pathway (Ehleringer and Monson, 1993), carnivory (Albert et al, 1992), N-fixing symbioses (Doyle, 1998), mycorrhizal symbioses (Fitter and Moyerson, 1996) and ecological traits (Ackerley, 1999), but also in the uptake of 134/137 Cs Willey et al, 2005), heavy metals (Broadley et al, 2001), Al (Jansen et al, 2002), Ca and a range of nutrients . It has been noted that phylogenies might be useful to estimating radionuclide transfer to plants (Beresford et al, 2004;Willey et al, 2005). Sr concentrations in different plant species are an inter-species comparison yet to be analysed phylogenetically.…”

Effect of waste mica on transfer factors of134Cs to spinach and lettuce

“…Clay minerals, micas and zeolites have been observed to reduce the phytoavailability of radiocesium to crops (Paasikallio, 1999) and the effectiveness of such amendments varies significantly depending on plant species and soil parameters (Frissel et al, 2002;Sachdev et al, 2006;Willey et al, 2005;Broadley and Willey, 1997).…”