Biogeochemical and photobiological responses of subarctic lakes to UV radiation.

Solar ultraviolet radiation (UV) induces photodegradation of optically and functionally important organic compounds in lakes and may negatively impact aquatic biota. We disentangled UV impacts on dissolved organic matter (DOM) transformation, and algal and zoobenthic micro-organisms in two shallow subarctic lakes in NW Finnish Lapland; in a high-UV + low-DOM (tundra, Iso-Jehkas) and a low-UV + high-DOM (mountain birch woodland, Mukkavaara) system. In addition to site and seasonal comparisons, in situ experiments with three treatments (DARK, photosynthetically active radiation [PAR], UV + PAR) were set up floating on the lakes for four weeks during midsummer.

Effects of climate and land-use changes on fish catches across lakes at a global scale.

Globally, our knowledge on lake fisheries is still limited despite their importance to food security and livelihoods. Here we show that fish catches can respond either positively or negatively to climate and land-use changes, by analyzing time-series data (1970-2014) for 31 lakes across five continents. We find that effects of a climate or land-use driver (e.

Alpine headwaters emerging from glaciers and rock glaciers host different bacterial communities: Ecological implications for the future.

Mountain glacier shrinkage represents a major effect of the current global warming and 80-100% of the Alpine glaciers are predicted to vanish within the next few decades. As the thawing rate of mountain permafrost ice is much lower than for glacier ice, a shift from glacial to periglacial dynamics is predicted for Alpine landscapes during the 21st century. Despite the growing literature on the impacts of deglaciation on Alpine hydrology and ecosystems, chemical and biological features of waters emerging from Alpine rock glaciers (i.

Isotopic biomonitoring of N pollution in rivers embedded in complex human landscapes.

The dynamic and hierarchical structure of rivers, together with disruption of the natural river continuum by human activities, makes it difficult to identify and locate sources of nutrient pollution affecting receiving waters and observe its dispersion, thus impairing monitoring efforts. The identification of reliable indicators of anthropogenic nitrogen inputs in catchments is therefore key to achieving effective management of polluted rivers. We tested the capacity of N isotopic signatures (δN) of epilithon and snails to provide useful indications of organic and inorganic anthropogenic N inputs in three Mediterranean rivers differing in terms of surrounding land use and physicochemical conditions.

Decadal trends in water chemistry of Alpine lakes in calcareous catchments driven by climate change.

High mountain lakes are considered sensitive indicators of the effects of natural and anthropogenic drivers, including atmospheric deposition and climate change. In this study, we assess long-term trends in the chemistry of a group of high altitude lakes in the Western Alps, Italy, lying in bedrock with a relevant presence of basic, soluble rocks. An in-depth investigation was performed on two key-sites (Lakes Boden Inferiore and Superiore) for which continuous chemical data are available for a period of 30 years.

First Isolation of Pseudogymnoascus destructans, the Fungal Causative Agent of White-Nose Disease, in Bats from Italy.

White-nose disease, caused by the dermatophyte Pseudogymnoascus destructans, is a devastating pathology that has caused a massive decline in the US bat populations. In Europe, this fungus and the related infection in bats have been recorded in several countries and for many bat species, although no mass mortality has been detected. This study reports for the first time the presence of P.

Plastic sources: A survey across scientific and grey literature for their inventory and relative contribution to microplastics pollution in natural environments, with an emphasis on surface water.

Plastic debris are at present recognized as an emerging potential threat for natural environments, wildlife and humans. In the past years an increasing attention has been addressed to investigate the presence and concentration of plastic debris in the ecosystems, including surface waters. Scientific literature extensively describes the ingestion by aquatic fauna, the transfer into food webs and the potential action as a vector for toxic compounds or alien microorganisms.

Widespread diminishing anthropogenic effects on calcium in freshwaters.

Calcium (Ca) is an essential element for almost all living organisms. Here, we examined global variation and controls of freshwater Ca concentrations, using 440 599 water samples from 43 184 inland water sites in 57 countries. We found that the global median Ca concentration was 4.

Comparison between kinetics of autochthonous marine bacteria in activated sludge and granular sludge systems at different salinity and SRTs.

Biological nutrient removal performances and kinetics of autochthonous marine biomass in forms of activated sludge and aerobic granular sludge were investigated under different salinity and sludge retention time (SRT). Both the biomasses, cultivated from a fish-canning wastewater, were subjected to stepwise increases in salinity (+2 gNaCl L), from 30 gNaCl L up to 50 gNaCl L with the aim to evaluate the maximum potential in withstanding salinity by the autochthonous marine biomass. Microbial marine species belonging to the genus of Cryomorphaceae and of Rhodobacteraceae were found dominant in both the systems at the maximum salinity tested (50 gNaCl L).

Microbiome profiling in extremely acidic soils affected by hydrothermal fluids: the case of the Solfatara Crater (Campi Flegrei, southern Italy).

An integrated geochemical and microbiological investigation of soils from the Solfatara Crater (Campi Flegrei, southern Italy) demonstrated that interstitial soil gases dominated by CO2 and other typical hydrothermal gaseous species (e.g. H2S, CH4, ethane, benzene, alkenes and S-bearing organic compounds) influenced the composition of microbial communities.

Urbanization and climate change impacts on surface water quality: Enhancing the resilience by reducing impervious surfaces.

Climate change and urbanization are key factors affecting the future of water quality in urbanized catchments. The work reported in this paper is an evaluation of the combined and relative impact of climate change and urbanization on the water quality of receiving water bodies in the context of a highly urbanized watershed served by a combined sewer system (CSS) in northern Italy. The impact is determined by an integrated modelling study involving two years of field campaigns.

The biogeochemical vertical structure renders a meromictic volcanic lake a trap for geogenic CO2 (Lake Averno, Italy).

Volcanic lakes are characterized by physicochemical favorable conditions for the development of reservoirs of C-bearing greenhouse gases that can be dispersed to air during occasional rollover events. By combining a microbiological and geochemical approach, we showed that the chemistry of the CO2- and CH4-rich gas reservoir hosted within the meromictic Lake Averno (Campi Flegrei, southern Italy) are related to the microbial niche differentiation along the vertical water column. The simultaneous occurrence of diverse functional groups of microbes operating under different conditions suggests that these habitats harbor complex microbial consortia that impact on the production and consumption of greenhouse gases.

Pore-scale simulations of concentration tails in heterogeneous porous media.

The retention of contaminants in the finest and less-conductive regions of natural aquifer is known to strongly affect the decontamination of polluted aquifers. In fact, contaminant transfer from low to high mobility regions at the back end of a contaminant plume (i.e.

Potential toxicity of environmentally relevant perfluorooctane sulfonate (PFOS) concentrations to yellow-legged gull Larus michahellis embryos.

Perfluooctane sulfonate (PFOS) is considered an emerging pollutant because of its wide distribution in both aquatic and terrestrial ecosystems, as well as its potential toxicity to living organisms. Although PFOS environmental levels and the adverse effects on classical model organisms in toxicological studies are well known, including developmental alterations and alteration of oxidative status, its toxicity to free-living species has been seldom investigated. The aim of this study was to assess the potential toxicity of environmental levels of PFOS to yellow-legged gull (Larus michahellis) embryos under field experimental conditions.

Hygienization performances of innovative sludge treatment solutions to assure safe land spreading.

The present research aims at the evaluation of the hygienization performances of innovative sludge treatment processes applied for the separated treatment of secondary sludge. Namely, two digestion pretreatments (sonication and thermal hydrolysis) and two sequential biological processes (mesophilic/thermophilic and anaerobic/aerobic digestion) were compared to the mesophilic (MAD) and thermophilic anaerobic digestion (TAD). Microbial indicators (Escherichia coli, somatic coliphages and Clostridium perfringens spores) and pathogens (Salmonella and enteroviruses), which show different resistances to treatment processes, were monitored in untreated and treated sludge.

Occurrence and sources of perfluoroalkyl acids in Italian river basins.

This paper presents a survey on the occurrence and sources of 11 perfluoroalkyl acids (PFAA) in the main river basins in Italy, covering about 40% of the Italian surface area and 45% of the Italian population. Total concentrations of PFAA ranged from View Article and Find Full Text PDF

Surrogate measures for providing high frequency estimates of total phosphorus concentrations in urban watersheds.

Until robust in situ sensors for total phosphorus (TP) are developed, continuous water quality measurements have the potential to be used as surrogates for generating high frequency estimates. Their use has widespread implications for water quality monitoring programmes considering that TP, in particular, is generally recognised as the limiting factor in the process of eutrophication. Surrogate measures for TP concentration, such as turbidity, have proved useful within natural and agricultural contexts, but their predictive capability for urban watersheds is considered more difficult, due to the different sources of TP, though a strict relationship with turbidity/suspended matter has been clearly described even for these environments.

Total phosphorus reference condition for subalpine lakes: a comparison among traditional methods and a new process-based watershed approach.

Different methods for estimating the total phosphorus (TP) reference conditions of lakes have rarely been compared. This work tests the uncertainty and accuracy of the most frequently used approaches (Morpho-edaphic index -MEI-, export coefficient, diatoms and pigment-inferred TP models) for 35 subalpine lakes. Furthermore, we propose a new process-based watershed approach that was tested on a subalpine environment and consists of combining a space for time substitution with a space for space substitution.

Sources and fate of perfluorinated compounds in the aqueous environment and in drinking water of a highly urbanized and industrialized area in Italy.

Perfluorinated substances are listed among emerging contaminants because they are globally distributed, environmentally persistent, bioaccumulative and potentially harmful. In a three-year monitoring campaign (2010-2013) we investigated the occurrence, sources and fate of nine perfluoroalkylcarboxylic acids and three perfluoroalkylsulfonic acids, in the most industrialized region of Italy. Composite samples were collected in influents and effluents of wastewater treatment plants (WWTPs), in the main rivers flowing through the basin, and in raw groundwater and finished drinking water.

Rheological measurements on different types of sewage sludge for pumping design.

Sewage sludge pumping could represent an optimal solution to assure adequate treatment of sludge in centralized plants, with a consequent reduction of the environmental impact of sludge disposal (volume, odour, putrescence), because small wastewater treatment plants usually do not provide an adequate treatment due to high costs. An accurate knowledge of rheological parameters is required to compute head loss for pipeline design, but only few data are available. In order to circumvent the problem of the scarcity of sludge rheological data, we have performed tests on different types of sludge, with solids concentration and temperature in the typical range of a conventional wastewater treatment plant.

Bacterial communities associated with benthic organic matter in headwater stream microhabitats.

Bacterial communities associated with a variety of benthic detritus types were studied in three streams in the context of the chemical characteristics of the sediment material and the stream water. A cell purification assay was developed for a quantitative microscopic evaluation of bacterial community structure in detritus samples by fluorescence in situ hybridization (FISH). The efficiency of FISH with fluorescently monolabelled probes was compared with FISH with signal amplification by catalysed reporter deposition (CARD-FISH).