Effects of ocean acidification, temperature and nutrient regimes on the appendicularian Oikopleura dioica: a mesocosm study

Increasing pCO₂ is hypothesized to induce shifts in plankton communities toward smaller cells, reduced carbon export rates and increased roles of gelatinous zooplankton. Appendicularians, among the most numerous pan-global “gelatinous” zooplankton, continuously produce filter-feeding houses, shortcutting marine food webs by ingesting submicron particles, and their discarded houses contribute significantly to carbon fluxes. We present a first mesocosm-scale study on the effects of temperature, pCO₂ and bloom structures on the appendicularian, Oikopleura dioica. There were effects of temperature and nutrients on phytoplankton communities. No shifts in functional phytoplankton groups, nor changes in particle sizes/morphotypes, known to impact appendicularian feeding, were observed under manipulated pCO₂ conditions. However, appendicularian abundance was positively correlated with increased pCO₂, temperature and nutrient levels, consistent with hypotheses concerning gelatinous zooplankton in future oceans. This suggests appendicularians will play more important roles in marine pelagic communities and vertical carbon transport under projected ocean acidification and elevated temperature scenarios.     

Monitoring of ambient BTX at Monterotondo (Rome) and indoor-outdoor evaluation in school and domestic sites

Results from a five month monitoring campaign of BTX (benzene, toluene and the sum of ethyl benzene, o-xylene, m-xylene and p-xylene), performed at Monterotondo, a little town 23 km NE of Rome, and correlation of the measured concentrations with meteorological and natural radioactivity data are presented and discussed. This campaign allowed us to extrapolate a pattern of the annual distribution of benzene in the town. A map, showing the average distribution of pollutants, is presented, as a useful tool to manage an appropriate policy of air pollution. A contemporary indoor-outdoor investigation has been performed at five homes and two classrooms of Monterotondo and at thirteen homes and thirteen classrooms in the outskirts of Rome. Non-smoking people and low polluted sites were chosen for this campaign, in order to highlight if commonly used domestic materials could act as internal sources. Data, obtained by employing long-term diffusive samplers, are compared with a parallel experiment showing the day-night indoor-outdoor trend. The obtained results, confirmed through statistical analysis of data, let us conclude that there is evidence of internal sources at homes whilst, in the schools, depletion phenomena prevail, probably due to the walls adsorption.     

Offsetting impacts of development on biodiversity and ecosystem services

Ambio - Offsetting—trading losses in one place for commensurate gains in another—is a tool used to mitigate environmental impacts of development. Biodiversity and carbon are the most...     

Evaluation of the effectiveness of red mud-supported catalysts in combination with ozone and TiO<Subscript>2</Subscript> in the treatment of solution containing benzene,toluene, and xylene

Ozone and a Fe²⁺/TiO₂-based catalyst were examined in the degradation of a synthetic solution of benzene toluene and xylene (BTX) in an advanced oxidation process (AOP). The catalyst beads were made from the slurry waste of aluminum production process, by inserting the TiO₂ content and subsequent calcination. The reduction of the BTX concentration load was monitored by the reduction of chemical oxygen demand (COD) and BTX concentration. Different levels were used on factors: pH, time of treatment, initial concentration of BTX, and percentage of TiO₂. The process was conducted in a bubble column reactor with the insertion of catalyst beads. A response surface methodology technique (CCD) was used to build a model based on COD reduction results. The model was optimized using the normal-boundary intersection (NBI) algorithm to maximize COD reduction and minimize the variance attributed to the process. Optimization led to COD reductions of 80% in 2 h of experiment. Correlation analysis of coefficient models from experimental data R²_adj was 0.9966, showing a good fit of model data. In the optimized conditions, the possible increase of the biodegradability ratio of the BTX solution, through the biochemical oxygen demand (BOD) and COD, was also analyzed. Under pre-treatment conditions, the BOD/COD ratio was 0.13. After the treatment, it increased to 0.56.

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Tributyltin chloride disrupts aortic vascular reactivity and increases reactive oxygen species production in female rats

Environmental Science and Pollution Research - Organotin compounds, such as tributyltin (TBT), are environment contaminants that induce bioaccumulation and have potential toxic effects on marine...     

Evaluation of modeling as a tool to determine the potential impacts related to drilling wastes in the Brazilian offshore

Numerical models that predict the fate of drilling discharges at sea constitute a valuable tool for both the oil industry and regulatory agencies. In order to provide reliable estimates, models must be validated through the comparison of predictions with field or laboratory observations. In this paper, we used the Offshore Operators Committee Model to simulate the discharges from two wells drilled at Campos Basin, offshore SE Brazil, and compared the results with field observations obtained 3 months after drilling. The comparison showed that the model provided reasonable predictions, considering that data about currents were reconstructed and theoretical data were used to characterize the classes of solids. The model proved to be a valuable tool to determine the degree of potential impact associated to drilling activities. However, since the accuracy of the model is directly dependent on the quality of input data, different possible scenarios should be considered when used for forecast modeling.     

Vulnerability of community businesses to environmental disasters

Business plays important roles in community functioning. ² However, disaster research has been disproportionately focused on units of analysis such as families, households and government agencies. This paper synthesises the major findings within the business development research field and the disaster research field. It constructs a framework for evaluating business vulnerability to natural disasters. Our theoretical integration of the research conducted to date addresses five major issues. First, it defines the ways in which businesses are subject to the impacts of natural disasters. Second, it identifies the factors that determine the magnitude of business impacts after a disaster. Third, it identifies how and when businesses return to their pre-disaster level in the disaster stricken community. Fourth, it describes measures that can be taken by individual firms and community planners to reduce the impacts of environmental disasters. Fifth, it identifies needs for public policy and future research to reduce business vulnerability to environmental disasters.     

Photolysis of flumequine: identification of the major phototransformation products and toxicity measures

Direct photolysis of flumequine (FLU, 20 mg L⁻¹) in different types of water (demineralised water (DW) and synthetic seawater (SW)), was conducted in a Suntest CPS + solar simulator to evaluate its persistence and toxicity, and to identify the major phototransformation products (PTPs) generated during photolysis in DW. It was observed that FLU is susceptible to transformation when subjected to direct solar radiation. The composition of the water affects the FLU degradation kinetics, which is slower in SW. Photolytic transformation products generated during direct photolysis were identified by liquid chromatography-time of flight-mass spectrometry (LC-TOF-MS). Fourteen PTPs generated in DW were identified. The transformation of FLU begins with the opening of the heterocyclic ring by oxidation of the double bond. Loss of the fluorine atom and the hydroxylation of the aromatic ring also appear as the majority, especially in the early stages. Comparative acute toxicity evaluation by Vibrio fischeri and Daphnia magna bioassays was performed for the first and last irradiated solutions in both matrices studied. These bioassays demonstrated that in the SW matrix, the most persistent PTPs are highly toxic to D. magna but less so to V. fischeri.