Secondary salinisation of rivers and streams is a global and growing threat that might be amplified by climate change. It can have many different causes, like irrigation, mining activity or the use of salts as de-icing agents for roads. Freshwater organisms only tolerate certain ranges of water salinity. Therefore secondary salinisation has an impact at the individual, population, community and ecosystem levels, which ultimately leads to a reduction in aquatic biodiversity and compromises the goods and services that rivers and streams provide. Management of secondary salinization should be directed towards integrated catchment strategies (e.g. benefiting from the dilution capacity of the rivers) and identifying threshold salt concentrations to preserve the ecosystem integrity. Future research on the interaction of salinity with other stressors and the impact of salinization on trophic interactions and ecosystem properties is needed and the implications of this issue for human society need to be seriously considered.

Despite considerable progress in ecotoxicology, it has become clear that this discipline cannot answer its central questions, such as, “What are the effects of toxicants on biodiversity?” and “How the ecosystem functions and services are affected by the toxicants?”. We argue that if such questions are to be answered, a paradigm shift is needed. The current bottom-up approach of ecotoxicology that implies the use of small-scale experiments to predict effects on the entire ecosystems and landscapes should be merged with a top-down macroecological approach that is directly focused on ecological effects at large spatial scales and consider ecological systems as integral entities. Analysis of the existing methods in ecotoxicology, ecology, and environmental chemistry shows that such integration is currently possible. Therefore, we conclude that to tackle the current pressing challenges, ecotoxicology has to progress using both the bottom-up and top-down approaches, similar to digging a tunnel from both ends at once.

The pot-culture experiment and field studies were conducted to screen out and identify cadmium (Cd) excluders from 40 Chinese cabbage genotypes for food safety. The results of the pot-culture experiment indicated that the shoot Cd concentrations under three treatments (1.0, 2.5 and 5.0 mg Cd kg⁻¹ Soil) varied significantly (p < 0.05), with average values of 0.70, 3.07 and 5.83 mg kg⁻¹, respectively. The Cd concentrations in 12 cabbage genotypes were lower than 0.50 mg kg⁻¹. The enrichment factors (EFs) and translocation factors (TFs) in 8 cabbage genotypes were lower than 1.0. The field studies further identified Lvxing 70 as a Cd-excluder genotype (CEG), which is suitable to be planted in low Cd-contaminated soils (Cd concentration should be lower than 1.25 mg kg⁻¹) for food safety. Lvxing 70 was identified as a Cd-excluder genotype (CEG) and suitable to be cultivated in low Cd-contaminated soils for food safety.

The Mediterranean environment, and most of the Italian peninsula, presents some peculiarities in terms of crop response to O3 since most physiological mechanisms activated upon O3 exposure, such as stomatal closure, often overlap and interact with those that underlie plant adaptation to drought and hyperosmotic stress, which are typical of these environments. OTC and EDU experiments have demonstrated that O3 causes strong yield losses when crops are grown without water limitations. However, exposure to water or saline stress significantly reduced O3 effects on crop yield. In this review, we present the methodological approaches that have been used to study plant-ozone interactions in Italy as well as biochemical, physiological and agronomic responses for representative cropping systems of the Mediterranean climate. Is the 22% yield loss due to ambient ozone in non-limiting water conditions a realistic estimate for moderately stressed crops, typical of most Mediterranean regions?

Although post-combustion emissions from power plants are a major source of air pollution, they contain excess CO₂ that could be used to fertilize commercial greenhouses and stimulate plant growth. We addressed the combined effects of ultrahigh [CO₂] and acidic pollutants in flue gas on the growth of Alternanthera philoxeroides. When acidic pollutants were excluded, the biomass yield of A. philoxeroides saturated near 2000 μmol mol⁻¹ [CO₂] with doubled biomass accumulation relative to the ambient control. The growth enhancement was maintained at 5000 μmol mol⁻¹ [CO₂], but declined when [CO₂ rose above 1%, in association with a strong photosynthetic inhibition. Although acidic components (SO₂ and NO₂) significantly offset the CO2 enhancement, the aboveground yield increased considerably when the concentration of pollutants was moderate (200 times dilution). Our results indicate that using excess CO₂ from the power plant emissions to optimize growth in commercial green house could be viable. Diluted post-combustion emission gas from fossil fuel fired power plants stimulate the growth of C₃ plant.

Particles of spent antifouling paint collected from a marine boatyard were ground and subsequently administered to the filter-feeding bivalve, Mytilus edulis, maintained in static aquaria. Concentrations of Cu and Zn were measured in seawater throughout a 16 h feeding phase and a 24 h depuration phase, in rejected and egested particles collected during the respective phases, and in the organisms themselves at the end of the experiments. Concentrations and distributions of Cu and Zn in processed particles indicated that M. edulis was able to ingest paint particles, regardless of whether nutritionally viable silt was present, and no mechanism of particle discrimination was evident. Enrichment of Cu and Zn in the visceral mass of individuals and in the aqueous phase during depuration supported these assertions, although elevated concentrations in other compartments of the organism (e.g. shell, gill) suggested that biotic and abiotic uptake of aqueous metal was also important. Particles of antifouling paint enriched in Cu and Zn are ingested and digested by the marine bivalve M. edulis.

This paper summarises some of the main results of a two-year experiment carried out in an Open-Top Chambers facility in Northern Italy. Seedlings of Populus nigra, Fagus sylvatica, Quercus robur and Fraxinus excelsior have been subjected to different ozone treatments (charcoal-filtered and non-filtered air) and soil moisture regimes (irrigated and non-irrigated plots). Stomatal conductance models were applied and parameterised under South Alpine environmental conditions and stomatal ozone fluxes have been calculated. The flux-based approach provided a better performance than AOT40 in predicting the onset of foliar visible injuries. Critical flux levels, related to visible leaf injury, are proposed for P. nigra and F. sylvatica (ranging between 30 and 33 mmol O3 m-²). Soil water stress delayed visible injury appearance and development by limiting ozone uptake. Data from charcoal-filtered treatments suggest the existence of an hourly flux threshold, below which may occur a complete ozone detoxification. The stomatal uptake of ozone is an important factor to evaluate visible injury appearance and evolution in plants.

Both eutrophication and SO₄ pollution can lead to higher availability of nutrients and potentially toxic compounds in wetlands. To unravel the interaction between the level of eutrophication and toxicity at species and community level, effects of SO₄ were tested in nutrient-poor and nutrient-rich fen mesocosms. Biomass production of aquatic and semi-aquatic macrophytes and colonization of the water layer increased after fertilization, leading to dominance of highly competitive species. SO₄ addition increased alkalinity and sulphide concentrations, leading to decomposition and additional eutrophication. SO₄ pollution and concomitant sulphide production considerably reduced biomass production and colonization, but macrophytes were less vulnerable in fertilized conditions. The experiment shows that competition between species, vegetation succession and terrestrialization are not only influenced by nutrient availability, but also by toxicity, which strongly interacts with the level of eutrophication. This implies that previously neutralized toxicity effects in eutrophied fens may appear after nutrient reduction measures have been taken. Interspecific competition, vegetation succession and terrestrialization in fens depend on the interacting effects of SO₄ pollution, sulphide toxicity and nutrient availability.

Volatile Organic Compounds (VOCs) emitted from vegetation (particularly isoprenoids) represent an important source of atmospheric hydrocarbons almost double the anthropogenic source. When biogenic VOC mix with NOx in the presence of UV radiation, ozone (O3) is formed. In Italy, optimal conditions for O3 formation in terms of VOC/NOx ratios and abundance of UV radiation occur for long periods of the year. Moreover, Italian vegetation includes several species that are strong and evergreen isoprenoid emitters, and high temperatures for part of the year further stimulate these temperature-dependent emissions. We review emission of isoprenoids from Italian vegetation, current knowledge on the impact of rising O3 levels on isoprenoid emission, and evidence showing that isoprenoids can increase both the O3 flux to the plant and protection against oxidative stress because of their antioxidant functions. This trait not only influences plant tolerance to O3 but also may substantially alter the flux of O3 between atmosphere and biosphere. The capacity to emit isoprenoids confers to plants tolerance to O3 and alters the flux of O3 between atmosphere and biosphere.

Macrocapsules, composed of a pH-sensitive polymer and phosphate buffer, offer a novel remediation alternative for acidic ground waters. To test their potential effectiveness, laboratory experiments were carried out followed by a field trial within a coal pile runoff (CPR) acidic contaminant plume. Results of traditional limestone and macrocapsule treatments were compared in both laboratory and field experiments. Macrocapsules were more effective than limestone as a passive treatment for raising pH in well water from 2.5 to 6 in both laboratory and field experiments. The limestone treatments had limited impact on pH, only increasing pH as high as 3.3, and armoring by iron was evident in the field trial. Aluminum, iron and sulfate concentrations remained relatively constant throughout the experiments, but phosphate increased (0.15-32 mg/L), indicating macrocapsule release. This research confirmed that macrocapsules may be an effective alternative to limestone to treat highly acidic ground water. Encapsulated phosphate buffer macrocapsules were more effective than limestone for passive treatment of acidic coal pile runoff (CPR) contaminated ground water, increasing pH from 2.5 to 6 in laboratory and field experiments.