Lucio Lucadamo

Environmental analysis of a regulated Mediterranean stream based on epilithic diatom communities – the Crati River case (southern Italy)

A regulated Mediterranean watercourse, the Crati River (Calabria, southern Italy) was studied during two different seasons. Benthic diatom samples were collected from eight stations. The environmental analysis of the Crati River was carried out using two diatom indices, one designed for the evaluation of water quality (EPI-D: Eutrophication Pollution Index – Diatom based), the other aimed at assessing physical disturbance on the basis of the proportion of motile species in the community, the Quantitative Navicula Nitzschia Surirella (QNNS) index. Within this group of algae the ratio between abundances of heterotrophs and autotrophs (NH:NA(NNS)) was also calculated as an estimate of water column turbidity. The biological quality of the river was assessed by comparing the EPI-D results with those of an assessment method based on macroinvertebrates (EBI: Extended Biotic Index). Chemical monitoring was adopted to evaluate both environmental quality and the sinking effect due to the Tarsia reservoir. The results suggest that both diatom and macro-invertebrate indices show a progressive increase of environmental impairment along the river, but EPI-D detects the strongest alterations, presumably due to an appreciable enrichment in nutrient concentrations and a moderate increase in organic load. The abatement of suspended solids and nutrient concentrations downstream from the Tarsia reservoir in July and their successive increase in November, when the barrage is opened, was registered mainly by variations of the QNNS and EPI-D and, secondarily, by a change in the NH:NA(NNS) ratio.

Evaluation of glyphosate drift and anthropogenic atmospheric trace elements contamination by means of lichen transplants in a southern Italian agricultural district

Ecophysiological biomarkers and atmospheric contamination due to glyphosate and trace elements were monitored in a southern Italian agricultural district by means of transplanted thalli of the lichen Pseudevernia furfuracea. Glyphosate exhibited a significant geographical pattern (east side > west side) and a drift source area equal to 32% of the monitoring sites. Moreover, based on the surface area of the study area and a wind quantitative relationship (WQR) with glyphosate thalli concentrations, our data support the idea that pesticide drift extends over an area of several square kilometers. Of the eight elements preliminarily classified as enriched, four were considered prevalently of geogenic origin (Al, Ti, Ni, Co) and four of anthropogenic origin (Cu, Mn, Sn, Sb), although only Sb and Cu passed rigorous statistical testing supporting a real difference from pre-exposure levels. The contribution of local sources was evaluated based on the relative increase of Cu, Mn, Sb, and Sn versus Ti. Cu and Mn were associated mainly with a biomass power plant (BPP), with Cu showing extremely high levels of contamination involving 20% of the monitoring sites. Sb and Sn were associated with spatial variation of the traffic rate. The mycobiont and photobiont showed an evident zonation of the levels of their physiological parameters, with oxidative stress being significantly associated with both the biomass power plant and Cu/Ti. Our results suggest that croplands are potentially exposed to various hazards: over-exposure to pesticides due to drift processes, diffuse low traffic levels promoting Sb enrichment, and acute Cu pollution affected by BPP emissions.