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.     

Conservation practitioners’ understanding of how to manage evolutionary processes

Both academics and practitioners consider a lack of knowledge about evolutionary theory to be a general barrier to effectively managing genetic diversity. However, it is challenging to judge practitioners’ level of understanding and how this influences their management decisions. Knowledge built through experience may be difficult for practitioners to articulate, but could nonetheless result in appropriate management strategies. To date, researchers have assessed only the explicit (formal) knowledge practitioners have of evolutionary concepts. To explore practitioners’ understanding of evolutionary concepts, it is necessary to consider how they might apply explicit and implicit knowledge to their management decisions. Using an online survey, we asked Australian practitioners to respond to 2 common management scenarios in which there is strong evidence that managing genetic diversity can improve outcomes: managing small, isolated populations and sourcing seeds for restoration projects. In describing their approach to these scenarios, practitioners demonstrated a stronger understanding of the effective management of genetic diversity than the definitions of the relevant concepts. However, their management of genetic diversity within small populations was closer to best practice than for restoration projects. Moreover, the risks practitioners described in implementing best practice management were more likely to affect their approach to restoration than translocation projects. These findings provide evidence that strategies to build the capacity of practitioners to manage genetic diversity should focus on realistic management scenarios. Given that practitioners recognize the importance of adapting their practices and the strong evidence for the benefits of actively managing genetic diversity, there is hope that better engagement by evolutionary biologists with practitioners could facilitate significant shifts toward evolutionarily enlightened management.     

Aptamers are an innovative and promising tool for phytoplankton taxonomy and biodiversity research

Nucleic acid aptamers are small-size ligands that selectively bind to molecular segments even when they protrude from cell surfaces. Due to their high specificity, aptamers are widely used in biomedical research and as probes for different applications. Here, we tested whether aptamers can also discriminate among phytoplankton cells. As a proof of concept we focused on the widespread centric diatom Leptocylindrus danicus and generated two aptamers that selectively bind to its cell surface. The aptamers did not bind to other diatoms tested, which included both pennate (Pseudo-nitzschia multistriata) and centric (Skeletonema marinoi, Chaetoceros socialis) species. They also showed negative binding to closely related species (Tenuicylindrus belgicus, Leptocylindrus aporus, Leptocylindrus convexus), which are hardly recognizable with microscopy techniques. In addition, aptamers discriminated also among cells of the same clone, suggesting a potential use of aptamers as clone-specific/stage-specific probes to track phytoplankton life stages in their natural environment. While the method still needs to be tested with natural algal samples, it can complement in a unique way the existing approaches to discriminate among species and possibly life stages of marine phytoplankton. The method can find useful application in taxonomic and ecological studies as well as in environmental monitoring including early warning strategies.     

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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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.     

Allocation of River Flows for Restoration of Floodplain Forest Ecosystems: A Review of Approaches and Their Applicability in Europe

Floodplain forests are flood-dependent ecosystems. They rely on well-timed, periodic floods for the provision of regeneration sites and on tapered flood recession curves for the successful establishment of seedlings. These overbank flood events are described as regeneration flows. Once floodplain forest trees are established, in order to grow they also require adequate, although variable, river stage levels or maintenance flows throughout the year. Regeneration flows are often synonymous with flood flows and only occur periodically. There is a disparity between this need for varied interannual flows over the decadal time frame and the usual annual cycle of flow management currently used by most river management agencies. Maintenance flows are often closer to established minimum flows and much easier to provide by current operational practices.A number of environmental flow methodologies, developed in North America, Australia, and South Africa are described in this review. They include the needs of the floodplain environment in the management and allocation of river flows. In North America, these methodologies have been put into practice in a number of river basins specifically to restore floodplain forest ecosystems. In Australia and South Africa, a series of related holistic approaches have been developed that include the needs of floodplain ecosystems as well as in-channel ecosystems. In most European countries, restoration of floodplain forests takes place at a few localized restoration sites, more often as part of a flood-defense scheme and usually not coordinated with flow allocation decisions throughout the river basin. The potential to apply existing environmental flow methodologies to the management of European floodplain forests is discussed.     

Fostering coastal resilience to climate change vulnerability in Bangladesh,Brazil, Cameroon and Uruguay: a cross-country comparison

This paper describes a comparative study of four different cases on vulnerability, hazards and adaptive capacity to climate threats in coastal areas and communities in four developing countries: Bangladesh, Brazil, Cameroon and Uruguay. Coastal areas are vulnerable to sea-level rise (SLR), storm surges and flooding due to their (i) exposure, (ii) concentration of settlements, many of which occupied by less advantaged groups and (iii) the concentration of assets and services seen in these areas. The objective of the paper is twofold: (i) to evaluate current evidence of coastal vulnerability and adaptive capacity and (ii) to compare adaptation strategies being implemented in a sample of developing countries, focusing on successful ones. The followed approach for the case evaluation is based on (i) documenting observed threats and damages, (ii) using indicators of physical and socioeconomic vulnerability and adaptive capacity status and (iii) selecting examples of successful responses. Major conclusions based on cross-case comparison are (a) the studied countries show different vulnerability, adaptive capacity and implementation of responses, (b) innovative community-based (CBA) and ecosystem-based adaptation (EbA) and (c) early warning systems are key approaches and tools to foster climate resilience. A recommendation to foster the resilience of coastal communities and services is that efforts in innovative adaptation strategies to sea-level rise should be intensified and integrated with climate risk management within the national adaption plans (NAPAs) in order to reduce the impacts of hazards.     

Determinants of social dominance and inheritance of agonistic behavior in an island population of silvereyes,Zosterops lateralis

Summary We examined components of agonistic behavior and dominance in parents and offspring of silvereyes on Heron Island, Great Barrier Reef, to discover their determinants. The data were collected over four years on 1,235 juveniles and their parents. Of four behavioral characters used to compare juveniles and their parents, bill clattering was seen significantly more among young from female parents that exhibited bill clattering. The total absence of submissive behavior and the total absence of aggressive behavior were shown more often than not by young from dominant male parents and subordinate female parents, respectively. Young fledging early in the breeding season tended to be more dominant than those fledging late in the season. The number of brood-mates or the local nest density did not affect the dominance of young. Dominance status appears to be little affected by the performance of parents.