May the Diversity of Epiphytic Lichens Be Used in Environmental Forensics?

Epiphytic (tree inhabiting) lichens, well-known biomonitors of atmospheric pollution, have a great potential for being used in environmental forensics. Monitoring changes in biodiversity is a useful method for evaluating the quality of an ecosystem. Lichen species occurring within an area show measurable responses to environmental changes, and lichen biodiversity counts can be taken as reliable estimates of environmental quality, with high values corresponding to unpolluted or low polluted conditions and low values to polluted ones. Lichen diversity studies may be very useful in the framework of environmental forensics, since they may highlight the biological effects of pollutants and constitute the base for epidemiological studies. It is thus of paramount importance that great care is taken in the interpretation of the results, especially in the context of a rapidly changing environment and facing global change scenarios. For this reason, it seems advisable to produce several zonal maps, each based on different species groups, and each interpreted in a different way. This exercise could also be a valid support in the framework of a sensitivity analysis, to support or reject the primary results. In addition, a clear and formal expression of the overall uncertainty of the outputs is absolutely necessary

Assessing Environmental Justice at the Urban Scale: The Contribution of Lichen Biomonitoring for Overcoming the Dichotomy between Proximity-Based and Distribution-Based Approaches

In this study, we tested the use of lichen biomonitoring techniques for the assessment of air quality disparities at the urban scale. We based our evaluation on the results of a previous lichen biomonitoring study carried out in Milan (Northern Italy), which estimates the contamination by potentially toxic elements (PTEs) and its distribution over the area, also providing an evaluation of the main emission sources. Therefore, we used the traditional methodologies for environmental justice assessment: the proximity-based and the distribution-based approaches. The workflow we propose is a data-driven selection of emission sources that contributes to overcoming the dichotomy between the two approaches and is now widely debated in the scientific community. A socio-economic deprivation index was elaborated for each census unit of Milan city and then related to the proximity of the emission sources previously selected. The results suggested that in the surrounding of industries and railways, the deprivation is higher, while the proximity of main roads is inhabited by wealthier populations. The distribution-based approach was run through a quantile regression analysis, and the outcome indicated that among the wealthier groups, an increase in contamination is followed by an increase in socio-economic deprivation, whilst among the deprived groups, people with greater economic opportunities tend, however, to live in worse air quality conditions due to the proximity of communication routes. This study poses the potential to review the classical methods of EJ assessment, providing a reliable workflow applicable in urban areas—the most vulnerable in terms of air quality disparities in the present and in the future

Lichen biomonitoring of trace elements in the Mt. Amiata geothermal area (central Italy)

The possible contribution of Al, Ba, Cd, Co, Cr, Cu, Fe, Mn, Mo, Pb, Sb, Sr, Ti, V and Zn from geothermal exploitation to the environmental contamination of Mt. Amiata was evaluated by assaying the epiphytic lichen Parmelia sulcata from two sampling areas: Piancastagnaio, where there are geothermal power plants, and a remote site distant from geothermal power plants. The results showed that the geothermal power plants at Piancastagnaio do not represent a macroscopic source of atmospheric contamination by most elements. On the other hand, there are indications that for Co, Mo and Sb emissions from the geothermal power plants are a source of air pollution

Suitability of XRF for Routine Analysis of Multi-Elemental Composition: A Multi-Standard Verification

This study investigated the suitability of X-ray fluorescence (XRF) analysis for routine multi-elemental composition analysis, checking its analytical capabilities by measuring a wide array of certified reference materials of soil and plant origin. A portable XRF analyzer was used to evaluate 32 soil and 12 plant standard materials, using both the Soil and Geochem mode, with sequential beams, allowing the detection of a wide range of elements. Recovery rates were calculated by comparing XRF measurements with certified values, and their correlations were verified through the Spearman coefficient. The results demonstrated the reliability of XRF measurements for soil samples, with a large number of elements showing a good or very good recovery and strong correlations with certified values. For plant samples, XRF largely overestimated the certified values, but the strong statistically significant correlations for almost all tested elements allowed us to correct this systematic bias, using the reported median value for dividing the value obtained via XRF. The Geochem mode emerged as more reliable for a larger number of elements. It was concluded that XRF may be a suitable alternative to ICP-MS in routine multi-elemental composition analysis

Influence of the Preservation Method on the Nutritional Profile of Elephant Garlic (Allium ampeloprasum L.) Grown in Valdichiana, a Traditional Cultivation Area of Tuscany, Italy

This study investigated the effect of two different methods, i.e. air-drying and freeze-drying, of preservation of elephant garlic (Allium ampeloprasum L.) cultivated in Valdichiana, a traditional cultivation area of Tuscany, Italy, on its nutritional characteristics (i.e. soluble proteins. polyphenols, flavonoids, free radical scavenging activity, starch, soluble sugars, allicin). The results showed that compared to the fresh product, the traditional method of air-drying causes significant reductions only in the total antioxidant power (-46%) and in the content of starch (-22%), while the modern method of freeze-drying negatively affects almost all the parameters investigated, overall by about 40%. The content of allicin is not changed by the preservation method. Although freeze-drying is considered one of the best methods for preserving plant-based food, attention should be paid to the effect of this process on the nutritional characteristics of the produc

Foliar Application of Wood Distillate Alleviates Ozone-Induced Damage in Lettuce (Lactuca sativa L.)

This study examined whether foliar applications of wood distillate (WD) have a protective effect on photosynthesis and the antioxidant power of lettuce when exposed to an ecologically relevant O3 concentration. Seedlings of lettuce (Lactuca sativa L.) were fumigated daily with 60 ppb of O3 for 30 days, five hours per day. Once per week, 50% of the fumigated plants were treated with foliar applications of 0.2% WD, while control plants were treated with water. The results clearly showed the ability of WD to protect lettuce plants from ozone-induced damage. Specifically, WD-treated plants exhibited lower damage to the photosynthetic machinery, assessed through a series of chlorophyll fluorescence parameters, a higher chlorophyll content, higher antioxidant power, as well as antioxidant molecules, i.e., caffeic acid and quercetin, and higher biomass. Counteracting the overproduction of ozone-generated reactive oxygen species (ROS) is speculated to be the main mechanism by which WD protects the plant from ozone-induced damage

Evaluating Seawater and Wood Distillate for Sustainable Hydroponic Cultivation: Implications for Crop Growth and Nutritional Quality

The adoption of innovative cultivation methods, such as hydroponics and aeroponics, is gaining attention due to the unprecedented demand for food that an increasing population is posing on agricultural systems, exacerbating the pressure on already limited arable land. Seeking sustainable and circular economy solutions is imperative, aiming to optimize water consumption and enhance crop yields and quality without resorting to synthetic chemical fertilizers. This study investigated the use of seawater at various concentrations as a base for nutrient solutions, with and without the addition of a natural biostimulant, wood distillate (WD). Four seawater (SW) concentrations (0, 3, 6, and 12%) and two wood distillate concentrations (0 and 0.2%) were applied to assess their impacts on lettuce growth. Findings reveal that seawater at low concentrations (< 6%) serves as an effective water-saving strategy, despite the reduction in the plant ascorbic acid contents. The addition of WD did not inflate growth; in fact, the results obtained are comparable to that of the controls for each concentration of seawater, except at the highest concentration (12% SW), resulting in reduced fresh leaf weights and root areas. Significantly, there was a notable increase in the ascorbic acid contents in all plants grown with WD. Moreover, the WD increased the leaf concentrations in Ca, Mg, P, and K, indicating the higher nutritional value of the crop. This research highlights the potential of combining seawater and WD for sustainable and efficient plant cultivation, suggesting new strategies for exploration across diverse plant species and hydroponic applications

Wood distillate (pyroligneous acid) boosts nutritional traits of potato tubers

Potato is the fourth most widely consumed staple food in the world. This study investigated the effectiveness of 0.2% wood distillate (WD), a biostimulant derived from the pyrolysis of waste plant biomass, in boosting the nutritional quality of potato tubers. The results showed that application of WD significantly increased the content of soluble sugars (sucrose +56.3%; glucose +44.9%; fructose +62.2%), starch (+35.1%) and total carbohydrates (+16.8%). Antioxidants (total antioxidant power, polyphenols, flavonoids) and most mineral elements (K, Mg, Ca, Na, Fe, Zn) were not affected. A lower content of Cu (−17.8%) and P (−24.5%) was found in WD-treated potato

Comparison of the Effect of Solid and Liquid Digestate on the Growth of Lettuce (Lactuca sativa L.) Plants

As a consequence of the Russian invasion of Ukraine, Europe is facing a shortage of chemical fertilizers for agriculture. Therefore, the use of byproducts of biomass anaerobic digestion, e.g., solid (SD) and liquid (LD) digestate, could be a key solution to cope with this problem. In this framework, the present study aimed to evaluate the effect of both SD and LD, derived from the same feedstock, on the biometric, physiological, and biochemical parameters of lettuce (Lactuca sativa L.) plants. Compared to the controls, the plants treated with 3% (w/w) SD showed a reduction in leaf fresh biomass, chlorophyll content, performance index, fractal dimension, and antiradical activity, while vitamin C increased by 18.8%. An opposite response was observed for the lettuce plants treated with 3% (v/w) LD, which showed an increase in all the above-mentioned parameters, except for vitamin C, which decreased by 39.8%. Interestingly, the content of malondialdehyde, which is correlated with cell membrane lipid peroxidation, increased in the SD-treated plants (+39.7%) and decreased (−42.1%) in the LD-treated plants. These results strongly support the use of LD in agriculture as a valuable product to improve the productivity and nutritional quality of crop plants

Učinci klime i poljoprivrede na vegetaciju epifitskih lišaja u Sredozemlju (Toskana, središnja Italija)

The epiphytic lichen vegetation on Quercus pubescens in Tuscany, central Italy, was investigated in agricultural and non- agricultural areas along an altitudinal transect characterized by different climatic conditions. The results show that lichen communities are influenced more by climate than agricultural practices, or at least that climatic parameters can mask any effects of agriculture. The presence and frequency of “nitrophytic” lichen species in agricultural sites was due to the xeric environment exacerbated by ploughing which raises much dust, rather than to nutrient enrichment of the habitat.Vegetacija epifitskih lišaja na hrastu meduncu (Quercuspubescens) istraživana je u poljoprivrednim i nepoljoprivrednim područjima Toskane (središnja Italija) pomoću visinskog transekta, duž kojega vladaju različite klimatske prilike. Rezultati pokazuju da klimatske prilike više utječu na zajednice lišaja nego poljoprivreda. Prisutnost i učestalost “nitrofitskih” vrsta lišaja u poljoprivrednim područjima više ovise o sušnoj okolini, nego o obogaćenju staništa hranjivim tvarima