Mineralization and Transfer Processes of <Superscript>14</Superscript>C-labeled Pesticides in Outdoor Lysimeters

A recently designed two-chamber-lysimeter-test-system allows the detailed investigation of degradation, transport and transfer processes of ¹⁴C-labeled substances in soil–plant–atmosphere-systems under outdoor conditions. With this test system it is feasible to distinguish between ¹⁴C-emissions from soil surfaces and ¹⁴C-emissions from plant surfaces in soil monoliths under real environmental conditions. Special soil humidity sensors allow the measurement of soil water content near to the soil surface, in 1 and 5 cm depth. The behavior of organic chemicals can be followed for a whole vegetation period and a mass balance for the applied chemical can be established. Some selected results of the herbicides isoproturon and glyphosate – using the two-chamber-lysimeter-test-system – are presented to demonstrate its applicability for the identification and quantification of the processes that govern pesticide behavior in soil–plant-systems. Mineralization of ¹⁴C-isoproturon was very different in four different soils; the mineralization capacity of the soils ranged from 2 to 60%. Leaching of isoproturon in general was very low, but depending on the soil type and environmental conditions isoproturon and its metabolites could be leached via preferential flow, especially shortly after application. For the herbicide ¹⁴C-glyphosate no accumulation of residues in the soil and no leaching of the residues to deeper soil layers could be observed after three applications. Glyphosate was rapidly degraded to AMPA in the soil. Glyphosate and AMPA were accumulated in soy bean nodules.     

Fractionation and ecotoxicological implication of potentially toxic metals in sediments of three urban rivers and the Lagos Lagoon,Nigeria, West Africa

The potential environmental impact of sediment-bound Cd, Cr, Cu, Pb and Zn in three trans-urban rivers in Lagos state and in the Lagos Lagoon was assessed by use of the modified Community Bureau of Reference (BCR) sequential extraction. The quality of the data was checked using BCR CRM 143R and BCR CRM 701. Good agreement was obtained between found and certified/indicative values. Of the rivers, the Odo-Iyaalaro, was generally the most contaminated and the Ibeshe the least. Higher concentrations of metals were generally found in the dry season compared to the wet season. Cadmium and Zn were released mostly in the acid exchangeable step of the sequential extraction, indicating that they have the greatest potential mobility and bioavailability of the analytes studied. Chromium and Cu were associated mainly with the reducible and oxidisable fractions, and Pb predominantly with the reducible and residual fractions. Sediments with the highest pseudototal analyte concentrations also released higher proportions of analytes earlier in the sequential extraction procedure. The study suggests that, during the dry season, potentially toxic metals (PTM) may accumulate in sediments in relatively labile forms that are released and can potentially be transported or bioaccumulate in the rainy season. Application of risk assessment codes and Hankanson potential risk indices indicated that Cd was the element of greatest concern in the Lagos Lagoon system. The study indicated that there is a need to strengthen environmental management and pollution control measures to reduce risk from PTM, but that even relatively simple strategies, such as seasonal restrictions on dredging and fishing, could be beneficial.     

Analysis of umbu (Spondias tuberosa Arruda (Anacardiaceae)) in different landscape management regimes

Plant domestication is an evolutionary process guided by human groups who modify the landscape for their needs. The objective of this study was to evaluate the phenotypic variations between populations of Spondias tuberosa Arruda (umbuzeiro) when subjected to different local landscape management strategies. The influence of the landscape management system on these populations was evaluated in five identified regional units (mountains, base of mountains, pastures, cultivated areas and home gardens). Ten individuals were randomly selected from each region and subjected to morphological and chemical fruit analysis. The diversity index, based on Simpson's index, was determined for the different populations. We then evaluated the morphological differences between the individual fruits from the distinct landscape areas. We observed no significant differences in morphological diversity between the areas studied. Our data suggest that the umbuzeiro specimens in this region may be in the process of incipient domestication.     

How Socio-Economic Conditions Influence Forest Policy Development in Central and South-East Europe

In this article, several findings on socio-economic conditions derived from national reports and a web-based questionnaire are discussed and related to the changing role of forestry and the future forest policy development. A number of Central and South-eastern European countries taking part in a SEE-ERA-NET project ReForMan project (www.reforman.de) participated in data acquisition: Austria, Bosnia and Herzegovina, Croatia, Germany, Serbia and Slovenia. The aim of the research was to illustrate the present structure of forestry sector, as well as investigate newly emerging topics in forestry of Central and South-eastern Europe. The results indicated certain patterns in attitudes and perceptions among stakeholders that can be related to socio-economic conditions defined for each country. Clear differences between member and non-member countries exist only in level of implementation of EU legislation. Results showed consensus on main threats to the forests among all countries, but also some country specifics in perceptions of factors influencing forestry, their importance and professional competencies. These results could be additionally explained by influence of historical conditions which shaped development of forest sector in SEE region especially in its organizational dimension as well as in perceived role of forestry expressed through recognition of main forest functions. The influence of European forest policy processes in the region is evident through adaptation of EU legislation and perceived implications of international processes on national levels. Based on this observation, two possible options for future development of the forestry sector can be foreseen: (i) focusing on the productive function of forests and fostering its' sustainable use; or (ii) putting an emphasis on environmental and social issues. In both cases supporting public participation in decision-making processes is recommendable. Another conclusion based on perceived medium to low professional competencies to cope with new topics, that there is lack of confidence and need for professional support in decisionmaking processes.     

Defining Chlorophyll-a Reference Conditions in European Lakes

The concept of “reference conditions” describes the benchmark against which current conditions are compared when assessing the status of water bodies. In this paper we focus on the establishment of reference conditions for European lakes according to a phytoplankton biomass indicator—the concentration of chlorophyll-a. A mostly spatial approach (selection of existing lakes with no or minor human impact) was used to set the reference conditions for chlorophyll-a values, supplemented by historical data, paleolimnological investigations and modelling. The work resulted in definition of reference conditions and the boundary between “high” and “good” status for 15 main lake types and five ecoregions of Europe: Alpine, Atlantic, Central/Baltic, Mediterranean, and Northern. Additionally, empirical models were developed for estimating site-specific reference chlorophyll-a concentrations from a set of potential predictor variables. The results were recently formulated into the EU legislation, marking the first attempt in international water policy to move from chemical quality standards to ecological quality targets.     

Heideggerian Environmental Virtue Ethics

Environmental ethics is apparently caught in a dilemma. We believe in human species partiality as a way of making sense of many of our practices. However as part of our commitment to impartialism in ethics, we arguably should extend the principle of impartiality to other species, in a version of biocentric egalitarianism of the kind advocated by Paul Taylor. According to this view, not only do all entities that possess a good have inherent worth, but they have equal inherent worth, and in particular no species is superior to any other. In this paper, I elaborate a Heideggerian environmental virtue ethics that slips between the horns of the dilemma. Central to this ethics is the relation of “dwelling” and the many virtues of dwelling, according to which the world is seen as “holy” in a variety of ways. This ethics is importantly local in respect of time and place, but also has universalistic aspects. To understand such an ethics, it is necessary to grasp Heidegger’s notion of truth as “aleithia” or opening, which enables us to escape the metaphysical dilemmas besetting ethics in the analytic tradition, including standard virtue ethics. Elaborating this notion occupies a large part of the paper.     

Identifying the antecedents of coping with an organizational acquisition: a structural assessment

This study used Lazarus and Folkman's ( 1984 ) cognitive–phenomenological model of coping and Lazarus's ( 1991 ) theory of emotions to develop and test a model of how individuals cope with an organizational acquisition. The model identifies the origins and process used to select both problem‐focused and emotion‐focused coping strategies. Covariance structure analysis of data from 172 individuals indicated that problem‐focused coping was directly influenced by primary appraisal and negative emotion, while only certain types of emotion‐focused coping were directly related to negative emotion. All coping strategies were impacted by social support. Furthermore, negative emotion was predicted by primary appraisal, which in turn was related to perceived control, coping efficacy, and environmental conditions. Recommendations for future research and applications are discussed. Copyright © 2000 John Wiley & Sons, Ltd.     

Communication with police supervisors and peers as a buffer of work‐related traumatic stress

Traumatic events are a particular type of stressor that may affect police officers engaged in front line duties. In this study, specific types of social support predicted to buffer the psychological and physical health effects of trauma are drawn from theory and empirical evidence in the area of post‐traumatic stress. Social support, measured as the content of communication, and the ease of talking about trauma was tested with 527 working police officers who responded to a questionnaire survey. Hierarchical regression analysis showed that the communication variables contributed to the variance in post‐traumatic stress disorder and physical symptoms with differential effects for different aspects of communication. Analysis of the effects of traumatic stress on symptoms for sub‐groups at different levels of communication showed that some types of communication, such as the ease of talking about trauma or positive communications about work, moderate the effects of stress for police officers, in that higher levels are associated with a weaker trauma–strain relationship. However, some types of communication buffered stress only at moderate levels and other types may not be protective. These results are discussed in terms of the types and sources of social support that are likely to buffer post‐traumatic stress at work. Copyright © 2000 John Wiley & Sons, Ltd.     

Eintragspfade von PCDD/PCDF-Belastungen über landwirtschaftliche Rohstoffe und Futtermittel in die menschliche Nahrungskette

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