The present study had the aim to evaluate the mining plant activities impact on forest ecosystems taking a common sense view of determination, at foliar level, of photosynthetic pigments content, of catalase’s and peroxydase’s activity - as enzymes involved in the defense against the reactive species of oxygen, the Krebs cycle dehydrogenases’ activity - as a main metabolic path generative of energy, but also of the microbial dehydrogenases’ activity from soil as a ecologic biomarker with key role in maintaining the soil’s quality. In parallel with the mentioned biochemical indicators were performed a series of histo-anatomic investigations. Were taken in study samples from the foliar tissue from two angiosperms species (Populus tremula L. and Salix caprea L.) from areas of Suceava’s County namely Rădăuţi (the reference area) and Crucea-Botuşana (area of uranium mining), but also samples of soil derived from different profiles of deepness (0-15 cm and 15-30 cm). The toxicity impact resulted as a consequence of anthropic activity of uranium holding in the Crucea area it is translated through an inferior content of a and b chlorophyll, the photosynthesis process being largely inhibited, in contrast with the superior net catalase’s, peroxidase’s, but also of foliar dehydrogenases’ activity, these enzymes laying out values even four times higher comparatively with the reference lot. The structural differences evidenced especially at the foliar limb level of the two species could be due to the anthropic pollution resulted as a consequence of the mining activity.