Combined sclerochronologic and oxygen isotope analysis of gastropod shells (Gibbula cineraria, North Sea): life-history traits and utility as a high-resolution environmental archive for kelp forests

The grey top-shell, Gibbula cineraria is a common member of temperate to cold water kelp forest communities, but its longevity and the age structure of its populations remains unresolved. Combined measurements of shell growth rates (sclerochronology) and oxygen isotope composition allow analysis of rate and timing of shell growth. Eight specimens were analyzed from the southern North Sea (near Helgoland, German Bight). Three age groups were identified but external measurements (width, height, ornamentation patterns and number of whorls) and shell weight are not adequate for ontogenetic age discrimination. Stable oxygen isotope data is consistent with shell growth during the interval from April to December in isotopic equilibrium with seawater, and growth increments exhibit strong tidal controls with fortnightly bundles well preserved. Reliable environmental proxy data (water temperature) can be extracted from the shell aragonite using conventional stable oxygen isotope analyses, with a temporal resolution of days attainable during intervals of maximum growth, but annual extremes are not always recorded in the shell. While demonstrating the utility of G. cineraria as a environmental and potential paleoenvironmental proxy for kelp forest habitats, its longevity has been significantly overestimated.     

Nutrient transfer by runoff from sewage sludge amended soil under simulated rainfall

Wastewater sludges are used in agriculture as soil amendment and fertilizer, with regard to their organic matter and nutrient content. However, availability of nitrogen and phosphorus from sludge-amended soils and their transfer in runoff may lead to eutrophication of downstream surface water. The aim of this study is to establish and compare the effect of two different sludges on these transfers: an anaerobically digested and thermically stabilised sludge (Seine-Aval treatment plant, sludge no. 1), and a limed sludge (Saint-Quentin treatment plant, sludge no. 2). Experiments were performed on 12 sloping micro-plots (1 m × 1 m) submitted to sludge spreading and controlled rainfall simulation. Runoff water was sampled and analysed for concentrations in nitrogen species and phosphorus. Results show that spreading of sludge no. 1 increased both ammonium nitrogen (mean of 1.1 mg L^–1 N-NH₄ vs. 0.2 mg L^–1 N-NH₄ for control micro-plots) and particulate phosphorus concentrations (mean of 2 mg L^–1 P vs. 1.1 mg L^–1 P for control micro-plots) in runoff water. On the other hand, sludge no. 2 did not induce any significant effect on nutrient concentrations in runoff. These results are related to chemical composition and physical treatment of sludges. This study underlines the existence of a short-term risk of nutrient mobilisation by runoff after sludge spreading on soil, and the need to check precisely the impact of this practice on water quality.     

Effect of Potassium Dichromate and Fenitrothion on Hemoglobins of Chironomus Riparius Mg. (Diptera, Chironomidae) Larvae: Potential Biomarker of Environmental Monitoring

In an attempt to identify Chironomus hemoglobins as biomarkers for environmental monitoring, alterations in the hemoglobins in Chironomus riparius Mg. (Diptera: Chironomidae) larvae, exposed to potassium dichromate and fenitrothion, were investigated under laboratory conditions. The hemoglobins were evaluated in terms of their total contents by a cyanomethemoglobin procedure, individual components by electrophoresis of isoelectric focusing, and their oxidation by multi wavelength rapid-scanning spectrophotometry. The total hemoglobin contents increased at the high level of fenitrothion exposure. No variations in the individual hemoglobin component levels were found, by exposure to either fenitrothion or potassium dichromate. Whereas, the absorption spectra of the hemoglobins showed decreases in the peaks corresponding to the oxyhemoglobins by exposure to both compounds, but more sensitively by the chromium, which probably reflects the increase of the autoxidation of the oxyhemoglobins to methemoglobins by these compounds. These results suggest that autoxidation of the hemoglobins in Chironomus riparius seems to be a sensitive parameter in response to redox-active chemical exposure, and this biochemical parameter could be developed as a biomarker in environmental monitoring.     

Different motivations for knowledge sharing and hiding: The role of motivating work design

Little research to date has focused on understanding employee motivation to share and hide knowledge. Using self‐determination theory, we tested the premise that knowledge sharing and hiding might be differentially motivated and that work design characteristics might influence the motivation to share knowledge with colleagues. In a panel survey of Australian knowledge workers and in a Chinese knowledge‐intensive organization, we asked knowledge workers, using time‐lagged designs, about perceptions of work design, motivation to share knowledge, and self‐reported knowledge sharing and hiding behaviors. Results, largely replicated across both samples, indicated that cognitive job demands and job autonomy were positively related to future reports of knowledge‐sharing frequency and usefulness via autonomous motivation to share knowledge. Unexpectedly, task interdependence was positively related to the three forms of knowledge hiding (evasive and rationalized hiding, and playing dumb) via external regulation to share knowledge. Implications for the design of jobs that motivate knowledge sharing and demotivate knowledge hiding are discussed.     

Application of high silica zeolite ZSM-5 in a hybrid treatment process based on sequential adsorption and ozonation for VOCs elimination

In this study, a hydrophobic synthetic zeolite, namely ZSM-5 is chosen as an adsorbent/catalyst for toluene removal. Experimental results showed that toluene adsorption onto ZSM-5 was favourable, following a Langmuir adsorption isotherm model. ZSM-5 zeolite was regenerated using gaseous ozone at low temperature. Adsorbed toluene was oxidised, releasing mainly CO₂ and H₂O. Traces of oxidation by-products such as acetic acid and acetaldehyde were formed and remained adsorbed after the oxidativate regeneration with ozone. After four successive cycles of adsorption/ozonation, the adsorption efficiency was not affected (92%–99%). These results showed that volatile organic compound (VOC) removal by adsorption onto ZSM-5 zeolite followed by ozone regeneration could be used as a promising hybrid process for the control of VOC emissions in terms of efficiency.     

An integrated environmental approach to investigate biomarker fluctuations in the blue mussel Mytilus edulis L. in the Vilaine estuary, France

Estuarine areas represent complex and highly changing environments at the interface between freshwater and marine aquatic ecosystems. Therefore, the aquatic organisms living in estuaries have to face highly variable environmental conditions. The aim of this work was to study the influence of environmental changes from either natural or anthropogenic origins on the physiological responses of Mytilus edulis. Mussels were collected in the Vilaine estuary during early summer because this season represents a critical period of active reproduction in mussels and of increased anthropogenic inputs from agricultural and boating activities into the estuary. The physiological status of the mussel M. edulis was evaluated through measurements of a suite of biomarkers related to: oxidative stress (catalase, malondialdehyde), detoxication (benzopyrene hydroxylase, carboxylesterase), neurotoxicity (acetylcholinesterase), reproductive cycle (vitelline, condition index, maturation stages), immunotoxicity (hemocyte concentration, granulocyte percentage, phagocytosis, reactive oxygen species production, oxidative burst), and general physiological stress (lysosomal stability). A selection of relevant organic contaminant (pesticides, (polycyclic aromatic hydrocarbons, polychlorobiphenyls) was measured as well as environmental parameters (water temperature, salinity, total suspended solids, turbidity, chlorophyll a, pheopigments) and mussel phycotoxin contamination. Two locations differently exposed to the plume of the Vilaine River were compared. Both temporal and inter-site variations of these biomarkers were studied. Our results show that reproduction cycle and environmental parameters such as temperature, organic ontaminants, and algal blooms could strongly influence the biomarker responses. These observations highlight the necessity to conduct integrated environmental approaches in order to better understand the causes of biomarker variations.     

Umweltvertr?glichkeitsprüfung (UVP) für Pl?ne und Programme

Zusammenfassung  Der Beitrag besch?ftigt sich mit der bald notwendigen Einführung einer Umweltvertr?glichkeitsprüfung für Pl?ne und Programme in das deutsche Umwelt-und Planungsrecht. Zun?chst werden Ziel und Zweck sowie europ?ischer Hintergrund dieses Umweltinstruments erl?utert. Sodann geht es um das Recht der Bauleitplanung. Es werden überlegungen angestellt, wie man den europ?ischen Anforderungen in diesem Bereich gerecht werden k?nnte. Siehe UWSF12 (6) 350 (2000) Schlagw?rter: deutsches Umwelt- und Planungsrecht; Pl?ne; Plan-UVP-Richtlinie; Programme; SEIA; Strategic Environmental Assessment (SEIA); Umweltvertraglichkeitsprüfung (UVP); UVP     

Environmental non-governmental organizations: key players in development in a changing climate��a case study of Mali

Developing countries are often most impacted by climate change. While the work of international environmental organizations has received considerable public and academic attention, local environmental non-governmental organizations (ENGOs) also play a key role in assisting local populations adapt to the changing environment and develop in a sustainable manner. Drawing on data from semi-structured interviews with rural Malians, and using a local ENGO [the Mali-Folkecenter Nyetaa (MFC)] as a case study, this paper begins by describing how rural Malians perceive climate change is impacting their lives, and how the MFC attempts to address these impacts with their programs in the communities. The paper then illustrates the unique advantages of local ENGOs, both in their holistic approach and their integration in the communities, to working with the local population, relative to the approach taken by larger NGOs in this field. It concludes by proposing that a key new avenue for the international community to meet its developmental and environmental goals could be to support the work of local ENGOs through, for example, existing carbon markets.