Impact of a flood disaster on sediment toxicity in a major river system--the Elbe flood 2002 as a case study

The ecotoxicological implications of a flooding disaster were investigated with the exceptional Elbe flood in August 2002 as an example. Sediment samples were taken shortly after the flood at 37 sites. For toxicity assessment the midge Chironomus riparius (Insecta) and the mudsnail Potamopyrgus antipodarum (Gastropoda) were exposed to the sediment samples for 28 days. For a subset of 19 sampling sites, the contamination level and the biological response of both species were also recorded before the flood in 2000. The direct comparison of biological responses at identical sites revealed significant differences for samples taken before and immediately after the flood. After flood sediments of the river Elbe caused both higher emergence rates in the midge and higher numbers of embryos in the mudsnail. Contrary to expectations the toxicity of the sediments decreased after the flood, probably because of a dilution of toxic substances along the river Elbe and a reduction in bioavailability of pollutants as a result of increasing TOC values after the flood.     

Body condition and the grouping behavior of brood-caring female common eiders (<Emphasis Type="Italic">Somateria mollissima</Emphasis>)

Both theoretical and empirical work has shown that group size increases with increasing ecological constraints on solitary breeding. Ecological constraints refer to extrinsic factors such as availability of breeding sites, food or mates. Common eider (Somateria mollissima) females pool their broods and share brood-rearing duties, or rear broods alone. Females are often in poor condition at hatching, as incubation is accomplished without feeding, and variation in body condition is largely environmentally induced and thus unpredictable. We found that the intensity of and duration of parental care that females provide is positively correlated with their body condition at hatching. This suggests that body condition is an ecological constraint on successful solitary breeding. We further observed that group productivity in common eider broods is a decelerating function of the number of tending females. As predicted, females in poorer condition (i.e., facing stronger ecological constraints) were found in larger groups. This result is straightforward if solitary tenders can enter any group at no cost. However, if entry is group-controlled, stable groups of non-relatives are predicted not to occur when per capita reproduction declines with group size. The N-person staying incentive model permits groups to form under these conditions, because reproduction is unevenly divided between dominants and subordinates in the group. We discuss the plausibility of these alternative models of group size for understanding the grouping behavior of brood-caring female common eiders.Communicated by M. Webster     

Modellierung von Stoffausbreitungen

Die Modellierung des Ausbreitungsverhaltens von Stoffen unterschiedlicher Eigenschaften in der Umwelt stellt eine Herausforderung dar, da die zugrundeliegenden physikalischen Transport-, chemischen Reaktions- und biologischen An- oder Abreicherungsprozesse zeitlich variabel in r?umlich heterogen strukturierten Umweltsystemen wirken. Durch geschickt gew?hlte Vereinfachungen, Abgrenzungen und Mittelungen sind bemerkenswerte Erfolge bis hin zur bedingt-prognostischen Simulation ausgew?hlter Stoffe und Stoffgruppen erzielt worden. Forschungsbedarf besteht vor allem in der Modellierung der kleinr?umigen, medienübergreifenden Ausbreitung von Stoffen in komplexen ?kosystemaren Zusammenh?ngen, einschlie?lich der Austausch- und Transfervorg?nge und der chemisch-biologischen Transformationen. Bericht vom 32. Tutzing-Symposium der DECHEMA e.V., 7. bis 10. M?rz 1994     

Recent European initiatives in marine protection policy: towards lasting protection for Europe's seas?

The seas and oceans are increasingly a focus of policy interest in Europe. This is mirrored in wide-ranging activities to manage and protect the marine environment, which raises the question of whether such activities go towards developing sustainable management of the seas. Sustainable management calls for an integrated and cross-sectoral approach in order to protect highly valuable marine biodiversity from sea- and land-based activities of all kinds. While some recent developments are fairly promising, there are still no moves on the policy agenda towards uniting all relevant European policy sectors – and particularly the Common Agricultural Policy and the Common Fisheries Policy – under the shared objective of sustainable management and protection of the marine environment and its resources.     

The contribution from shipping emissions to air quality and acid deposition in Europe

A global three-dimensional Lagrangian chemistry-transport model STOCHEM is used to describe the European regional acid deposition and ozone air quality impacts along the Atlantic Ocean seaboard of Europe, from the SO2, NOx, VOCs and CO emissions from international shipping under conditions appropriate to the year 2000. Model-derived total sulfur deposition from international shipping reaches over 200 mg S m(-2) yr(-1) over the southwestern approaches to the British Isles and Brittany. The contribution from international shipping to surface ozone concentrations during the summertime, peaks at about 6 ppb over Ireland, Brittany and Portugal. Shipping emissions act as an external influence on acid deposition and ozone air quality within Europe and may require control actions in the future if strict deposition and air quality targets are to be met.     

Effects of three biochars on copper immobilization and soil microbial communities in a metal-contaminated soil using a metallophyte and two agricultural plants

Environmental Geochemistry and Health - Biochar (BC) is a porous, carbonaceous material produced by slow pyrolysis of biomass under oxygen-limited conditions. BC production has been attracting...     

Land cover composition determinants in the Uckermark (NE Germany) over a 220-year period

There is broad consensus that land use/cover has changed in central Europe over millennia. However, few studies have addressed the roles of the anthropogenic (socio-economic) and natural (biophysical) factors driving these changes over shorter periods (e.g., 100 years). In this study, we analyse the determinants of land cover composition at three discrete time periods (c. 1780, 1890, and 2000). We hypothesise that different anthropogenic and natural factors are the determinants of the main land cover types (arable fields, grasslands, and forests) and that the effects of natural and anthropogenic factors on the main land cover types differ among landscapes with highly dynamic and more stable forest-open land distributions. The study was carried out in the Uckermark region located in northeastern Germany. We compiled data on natural and anthropogenic factors (e.g. forest cover and number of inhabitants) of 65 municipalities in four landscape sections of equal size (10 × 10 km). Landscape sections were selected to reflect different dynamics (high/low) in conversion from forest to arable fields or grasslands and vice versa from 1780 to 2000. Averaged linear mixed-effect models explained between 7.5 and 81.2 % of the variance. The unique effect of anthropogenic factors varied from 2.1 to 18.7 % and that of natural factors varied from 0.2 to 43.4 %. In four of six models that included both types of factors, the natural factors were more influential than the anthropogenic factors. Except in three cases, anthropogenic and natural factors showed opposite effects on land cover types in more dynamic and more stable windows. Though the Uckermark region has been influenced by human activity for thousands of years, natural factors were a major determinant of land cover composition during all time periods, whereas anthropogenic factors became more important only during the latest time period under investigation.     

Decadal variability of floods in the northern foreland of the Tatra Mountains

Floods in the northern foreland of the Tatra Mountains considerably contribute to the total flood damage in Poland. Therefore, the question whether the magnitude and frequency of floods have changed in this region is of high interest. This study aims at investigating the inter-decadal variability of magnitude, frequency and seasonality of floods since the mid-twentieth century, to better understand regional changes. The analysis was accomplished in a multi-temporal approach whereby trends are fitted to every possible combination of start and end years in a record. Detected trends were explained by estimating correlations between the investigated flood parameters and different large-scale climate indices for the northern hemisphere, and by trends found in intense precipitation indices, number of days with snow cover, cyclonic circulation types, temperature and moisture conditions. Catchment and channel changes that occurred in the region over the past decades were also considered. Results show that rivers in the area exhibit considerable inter-decadal variability of flows. The magnitude and direction of short-term trends are heavily influenced by this inter-decadal variability; however, certain patterns are apparent. More extreme, although perhaps less frequent floods are now likely to occur, with a shift in the seasonality, decreasing flood magnitudes in winter and increasing during autumn and spring. The identification of the factors contributing to the occurrence of flood events and their potential changes is valuable to enhance the flood management in the region and to improve the resilience of the population in this mountainous area.     

Dioxin- and POP-contaminated sites—contemporary and future relevance and challenges

BACKGROUND, AIM AND SCOPE: Once they have been generated, polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) and other persistent organic pollutants (POPs) can persist in soils and sediments and in waste repositories for periods extending from decades to centuries. In 1994, the US EPA concluded that contaminated sites and other reservoirs are likely to become the major source of contemporary pollution problems with these substances. With this in mind, this article is the first in a new series in ESPR under the title 'Case Studies on Dioxin and POP Contaminated Sites--Contemporary and Future Relevance and Challenges', which will address this important issue. The series will document various experiences from sites contaminated with PCDD/F and other POPs. This article provides an overview of the content of the articles comprising the series. In addition, it provides a review of the subject in its own right and identifies the key issues arising from dioxin/POP-contaminated sites. Additionally, it highlights the important conclusions that can be drawn from these examples. The key aim of this article and of the series as a whole is to provide a comprehensive overview of the types of PCDD/F contaminated sites that exist as a result of historical activities. It details the various processes whereby these sites became contaminated and attempts to evaluate their contemporary relevance as sources of PCDD/Fs and other POPs. It also details the various strategies used to assess these historical legacies of contamination and the concepts developed, or which are under development, to effect their remediation. MAIN FEATURES: Special sessions on 'Contaminated sites--Cases, remediation, risk and policy' were held at the DIOXIN conferences in 2006 and 2007, and this theme will be continued at DIOXIN 2008 to be held in Birmingham. Selected cases from the approximately 70 contributions made to these sessions, together with some additional invited case studies are outlined together with the key issues they raise. By evaluating these cases and adding details of experiences published in the current literature, an overview will be given of the different features and challenges of dioxin and POP-contaminated sites. RESULTS: This article provides a systematic categorisation of types of PCDD/F and POP-contaminated sites. These are categorised according to the chemical or manufacturing process, which generated the PCDD/Fs or POPs and also includes the use and disposal aspects of the product life cycle in question. The highest historical PCDD/F and dioxin-like polychlorinated biphenyl (PCB) contamination burdens have arisen as a result of the production of chlorine and of chlorinated organic chemicals. In particular, the production of chlorinated pesticides, PCBs and the related contaminated waste streams are identified being responsible for historical releases of toxic equivalents (TEQs) at a scale of many tonnes. Along with such releases, major PCDD/F contaminated sites have been created through the application or improper disposal of contaminated pesticides, PCBs and other organochlorine chemicals, as well through the recycling of wastes and their attempted destruction. In some extreme examples, PCDD/F contaminated sites have also resulted from thermal processes such as waste incinerators, secondary metal industries or from the recycling or deposition of specific waste (e.g. electronic waste or car shredder wastes), which often contain chlorinated or brominated organic chemicals. The examples of PCDD/F and dioxin-like PCB contamination of fish in European rivers or the impact of contaminated sites upon fishing grounds and upon other food resources demonstrate the relevance of these historical problems to current and future human generations. Many of the recent food contamination problems that have emerged in Europe and elsewhere demonstrate how PCDD/F and dioxin like PCBs from historical sources can directly contaminate human and animal feedstuffs and indeed highlight their considerable contemporary relevance in this respect. Accordingly, some key experiences and lessons learnt regarding the production, use, disposal and remediation of POPs from the contaminated sites are summarised. DISCUSSION: An important criterion for evaluating the significance and risks of PCDD/Fs and other POPs at contaminated sites is their present or future potential for mobility. This, in turn, determines to a large degree their propensity for off-site transport and environmental accessibility. The detailed evaluation of contaminated site cases reveals different site-specific factors, which influence the varied pathways through which poor water-soluble POPs can be mobilised. Co-contaminants with greater water solubility are also typically present at such sites. Hence, pumping of groundwater (pump and treat) is often required in addition to attempting to physically secure a site. At an increasing number of contaminated sites, securing measures are failing after relatively short time spans compared to the time horizon, which applies to persistent organic pollutant contamination. Due to the immense costs and challenges associated with remediation of contaminated sites 'monitored natural attenuation' is increasingly gaining purchase as a conceptual remediation approach. However, these concepts may well prove limited in their practical application to contaminated sites containing persistent organic pollutants and other key pollutants like heavy metals. CONCLUSIONS: It is inevitable, therefore, that dioxin/POP-contaminated sites will remain of contemporary and future relevance. They will continue to represent an environmental issue for future generations to address. The securing and/or remediation of dioxin/POP-contaminated sites is very costly, generally in the order of tens or hundreds of millions of dollars. Secured landfills and secured production sites need to be considered as constructions not made for 'eternity' but built for a finite time scale. Accordingly, they will need to be controlled, supervised and potentially repaired/renewed. Furthermore, the leachates and groundwater impacted by these sites will require ongoing monitoring and potential further remediation. These activities result in high maintenance costs, which are accrued for decades or centuries and should, therefore, be compared to the fully sustainable option of complete remediation. The contaminated site case studies highlight that, while extensive policies and established funds for remediation exist in most of the industrialised western countries, even these relatively well-regulated and wealthy countries face significant challenges in the implementation of a remediation strategy. This highlights the fact that ultimately only the prevention of contaminated sites represents a sustainable solution for the future and that the Polluter Pays Principle needs to be applied in a comprehensive way to current problems and those which may emerge in the future. RECOMMENDATIONS AND PERSPECTIVES: With the continuing shift of industrial activities in developing and transition economies, which often have poor regulation (and weak self-regulation of industries), additional global challenges regarding POPs and other contaminated sites may be expected. In this respect, a comprehensive application of the "polluter pays principle" in these countries will also be a key to facilitate the clean-up of contaminated areas and the prevention of future contaminated sites. The threats and challenges of contaminated sites and the high costs of securing/remediating the problems highlight the need for a comprehensive approach based upon integrated pollution prevention and control. If applied to all polluting (and potentially polluting) industrial sectors around the globe, such an approach will prove to be both the cheapest and most sustainable way to underpin the development of industries in developing and transition economies.