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An attempt to link phytomanagement, art and social involvement is presented. The "Remediation" Project started up from the search of sustainable solutions for the management of a riparian area in the city of Rome. With the participation of citizens, researchers carried out a preliminary survey on the presence of metals within the target ecosystem and a demonstrative experiment on phytoremediation. Several social and cultural events have been organized in connection with the scientific part of the project: a public debate, an art exposition, a performance and two workshops at the experimental field. The Project demonstrated that through art it is possible to raise curiosity on scientific issues; the participated survey on metal pollution highlighted the strict interconnection among environmental matrices (soil/water/bioma) and thus the risk of contamination transfer; the demonstrative experiment, even if very basic in order to be easily approached by citizens, showed the great potential of Nature Based Solutions. [ABSTRACT FROM AUTHOR]

There is growing interest in developing environment-friendly farming practices that can limit the impact of drought stress in agriculture. The main objective of this study was to investigate the combined effects of biochar and arbuscular mycorrhizal fungi (AMF) on the agronomic responses of sunflower. Field experiments were conducted in the 2018 and 2019 growing seasons in semi-arid environments of Iran. The following treatments were adopted: i) three levels of biochar [0, 2.5 and 5 t ha–1 of biochar called Bl, Bm and Bh, respectively]; and ii) three irrigation levels (50, 30 and 10% of the maximum available water (MAW) called 50MAW, 30MAW and 10MAW, respectively)]; iii) two levels of AMF inoculation (with and without the addition of AMF called +AMF and –AMF, respectively). The experimental design was a randomized complete block design. At flowering, the leaf area index (LAI) was generally higher in the plants subjected to Bh-+AMF (on average 4.95), even if the LAI values changed according to biochar application (Bh > Bm > Bl) and the level of irrigation (50MAW > 30MAW > 10MAW). At harvesting, sunflower seed yield was highest in +AMF and in Bh (on average 53.9 and 51.2 g plants–1, respectively). Sunflower plants subjected to Bh-+AMF showed the highest seed yield under all irrigation levels (79.4, 57.1 and 32.3 g plant–1 in 50MAW, 30MAW and 10MAW, respectively). The application of biochar combined with AMF resulted in an increase in agronomic responses compared to untreated plants (Bl- –AMF) such as root biomass (+15%), stem diameter (+12%), plant height (+5%) and head diameter (+15%). Seed protein was higher in +AMF than –AMF (on average 20.7 vs 17.2 g m–2, respectively) and in Bh and Bm compared with Bl (on average 19.4 vs 18.2 g m–2, respectively). The oil content of seeds was affected by biochar application and AMF inoculation, especially under 50MAW and 30MAW irrigation levels; conversely, no differences were observed under the 10MAW irrigation level. Sunflower yield characteristics were positively correlated to the net photosynthesis rate and negatively affected by hydrogen peroxide and malondialdehyde content. The results showed that the adoption of biochar and AMF may represent as a successful strategy to balance crop productivity in a semi-arid environment. Although further research is required for a better understanding of the irrigation and fertilization schedule, these preliminary results could be extended to other crops which have similar requirements to sunflower. [ABSTRACT FROM AUTHOR]

Pleurotus ostreatus dual biofilms with bacteria are known to be involved in rock phosphate solubilization, endophytic colonization, and even in nitrogen fixation. Despite these relevant implications, no information is currently available on the architecture of P. ostreatus -based dual biofilms. In addition to this, there is a limited amount of information regarding the estimation of the temporal changes in the relative abundances of the partners in such binary systems. To address these issues, a dual biofilm model system with this fungus was prepared by using Pseudomonas alcaliphila 34 as the bacterial partner due to its very fast biofilm-forming ability. The application of the bacterial inoculum to already settled fungal biofilm on a polystyrene surface coated with hydroxyapatite was the most efficient approach to the production of the mixed system the ultrastructure of which was investigated by a multi-microscopy approach. Transmission electron microscopy analysis showed that the adhesion of bacterial cells onto the mycelial cell wall appeared to be mediated by the presence of an abundant layer of extracellular matrix (ECM). Scanning electron microscopy analysis showed that ECM filaments of bacterial origin formed initially a reticular structure that assumed a tabular semblance after 72 h, thus overshadowing the underlying mycelial network. Across the thickness of the mixed biofilms, the presence of an extensive network of channels with large aggregates of viable bacteria located on the edges of their lumina was found by confocal laser scanning microscopy; on the outermost biofilm layer, a significant fraction of dead bacterial cells was evident. Albeit with tangible differences, similar results regarding the estimation of the temporal shifts in the relative abundances of the two partners were obtained by two independent methods, the former relying on qPCR targeting of 16S and 18S rRNA genes and the latter on ester-linked fatty acid methyl esters analysis. [ABSTRACT FROM AUTHOR]

According to EU Strategy for the Baltic Sea Region, Lithuania obligates to ensure sustainable growth, gain and maintain good condition of marine environment until 2020. In accordance with the sustainability approach, every potential cost and energy cutting as well as social sustainability measure for wastewater treatment should be explored. Nonetheless, Lithuania wastewater treatment plants (WWTP) in the sustainability context have never been evaluated before. A comprehensive set of 30 sustainable development indicators (SDI) (9 functional, 11 environmental, 5 economical and 6 socio-cultural) in connection with functional unit were applied to medium-sized Jurbarkas WWTP (with a capacity of 2,540 m³/d). Sustainability evaluation involved life cycle of WWTP maintenance phase as well as water inlet, outlet and manufacturing. Results revealed that in the general context of sustainability the stability of plant varied greatly. Nine SDI haven't reached the sustainability approach. Graphically systemized results in the four sustainability categories have shown that relatively highest environmental impact regarding the maximum covered plot is caused due to an economical unsustainability. Operational and maintenance costs per volume of wastewater treated were approximately 2.23 higher than the cost to consumers per one cubic meter of wastewater treated, therefore depreciation, repairs, material costs and wastewater treatment costs accounted to 87%. Methodology by using SDI for estimating sustainability of WWTP is adaptable to different capacity or technology of WWTP, comparable, simple to develop and improve. [ABSTRACT FROM AUTHOR]

Water availability, together with temperature, represents the most limiting abiotic factor regulating soil CO2 efflux (SR). Besides the direct effect of water limitation, drought also influences plant activity, determining changes in the quality and quantity of root exudates, thus indirectly affecting soil microbial activity. To determine how the seasonal changes of plant activity and soil microbial metabolism and structure affect SR response to drought, we investigated the correlation between leaf gas exchange, soil carbon pools and soil respiration sources and the role of soil carbon pools on microbial populations and soil respiration, in a summer deciduous Mediterranean (SDS) and a winter deciduous temperate (WDS) shrublands, experiencing a dry summer period. In both sites, drought reduced photosynthesis, but affected SR differently: in SDS, SR decreased, although microbial heterotrophic respiration (SRh) remained unchanged; in WDS, SR did not vary but SRh was reduced. While in SDS the microbial community was able to respire more complex substrates, in WDS it was strongly dependent on easily decomposable molecules, thus on plant activity. Therefore, the response of soil CO2 efflux to water limitation is not exclusively influenced by climate as it is modulated by the degree of adaptation of the microbial community to drought. [ABSTRACT FROM AUTHOR]

In this work, three different arsenic-rich well waters from the territory of Viterbo (Italy) were processed via electrodialysis (ED) to remove arsenic. These waters having different chemico-physical parameters (i.e. pH, electric conductivity, main anion and cation, as well as arsenic, concentrations) were preliminarily submitted to limiting current tests to determine the electric current to be applied in constant-current batch desalination trials by using a laboratory-scale electrodialyzer. Arsenic removal was non-selective, its percentage removal (ρAs) being about 71% of the desalination degree (DD) achieved (i.e. 80–85%) at the end of any batch desalination. The specific energy consumption (w) was found to be linearly related to DD in the range of 71–75 W h m−3. Thus, contrary to generally accepted belief, arsenic removal by ED resulted to be by far less energy intensive than reverse osmosis, its specific energy consumption being almost of the same order of magnitude as that associated with the ED removal of nitrates from drinking water. Two empirical relationships (ρAs and w against DD) were developed to assess firstly the DD associated with prefixed arsenic removal and then to estimate the corresponding specific electric energy consumption. [ABSTRACT FROM AUTHOR]

Different fractions of Ni, Zn, Cu and Pb were determined in metal-spiked forest soils derived from four parent materials using three extractants (H2O, CaCl2 and diethylenetriaminepentaacetic acid (DTPA)). It is important to determine how parent materials and soil properties affect the retention of these metals in order to predict their behavior and act accordingly in the event of accidental spillage, for example. The extraction of fractions was not sequential (before carrying out the extractions, the soil samples were divided into three parts), so the CaCl2 fraction also included the H2O one, and the DTPA fraction contained the other two. With the results, we developed models to predict the extraction of each fraction employing the physicochemical characteristics of the soil (e.g., pH, organic matter content and texture values) and the amount of metal added. The objective of this work was to determine how the properties of the soil would influence the fractioning of the metals considered, and through these characteristics create models to predict the behavior of each metal fraction. We found correlations between the different fractions of Ni and Zn, suggesting that there are soil properties that condition the retention of both metals. Pb and Cu showed different behavior than Zn or Ni, since the proportions extracted by H2O and CaCl2 were much lower. Regarding the DTPA fraction, unlike the case of Ni or Zn, the extraction of Cu and Pb was more homogeneous; they did not show great variation in different soils, even when considering the results of extraction in limestone soils. This may be due to the fact that the soil properties do not exert an important effect on their availability, or these two metals are considerably sensitive to the effect of pH, and no differences were observed because the extraction of the DTPA fraction was conducted with a buffered solution. For each fraction of metal used, we obtained a model with R2 always greater than 0.65. Considering these results, we can conclude that it is possible to predict Zn, Ni, Cu and Pb availability in soils developed on different parent materials. This can be achieved by identifying some basic soil characteristics and applying the developed equations. [ABSTRACT FROM AUTHOR]