Soil Arsenic toxicity impact in the growth and C-assimilation of Eucalyptus nitens

Abstract

Abstract The selection of suitable plant species that can live in contaminated and abandoned mining areas is a goal environmental managers and policy makers. In this framework, the use of a fast-growing forestry species such as Eucalyptus nitens in the recovery of As from artificial contaminated soils was studied during a long-term experiment. Roots can accumulate levels ranging between 69.8 and 133 µg g− 1 for plants treated with 100 As and 200 As, respectively, while leaves between 9.48 µg g− 1 (200 As) and 15.9 µg g− 1 (100 As) without apparent morphological damage and toxicity symptoms. The performance of the photosynthetic apparatus showed a gradual impact in some gas exchange parameters such as net photosynthetic rate (Pn), stomatal conductance to H2O (gs) and the transpiration rate (E), particularly with the use of the highest As concentration (200 As), but without significant impacting the PSII performance. The effects of As on the uptake and translocation of Ca, Fe, K and Zn revealed two major interferences. The first one related with Zn where a moderate antagonism was detected, and the second one related with Fe, where a particular enrichment in E. nitens leaves was noted in both As treatments. Thus, it seems to exist a synergistic action with impact in the levels of the photosynthetic pigments in As treated plant leaves, compared with control plants. In face of the acquired data, E. nitens must be considered as an alternative when phytoremediation processes are put in practice in our country.