Dissolved phosphorus transport from soil to surface water in catchments with different land use

Diffuse phosphorus (P) export from agricultural land to surface waters is a significant environmental problem. It is critical to determine the natural background P losses from diffuse sources, but their identification and quantification is difficult. In this study, three headwater catchments with differing land use (arable, pasture and forest) were monitored for 3 years to quantify exports of dissolved (<0.45 µm) reactive P and total dissolved P. Mean total P exports from the arable catchment ranged between 0.08 and 0.28 kg ha^?1 year^?1. Compared with the reference condition (forest), arable land and pasture exported up to 11-fold more dissolved P. The contribution of dissolved (<0.45 µm) unreactive P was low to negligible in every catchment. Agricultural practices can exert large pressures on surface waters that are controlled by hydrological factors. Adapting policy to cope with these factors is needed for lowering these pressures in the future.     

The structure of the fire fighting foam surfactant Forafac®1157 and its biological and photolytic transformation products

For several decades, perfluorooctane sulfonate (PFOS) has widely been used as a fluorinated surfactant in aqueous film forming foams used as hydrocarbon fuel fire extinguishers. Due to concerns regarding its environmental persistence and toxicological effects, PFOS has recently been replaced by novel fluorinated surfactants such as Forafac®1157, developed by the DuPont company. The major component of Forafac®1157 is a 6:2 fluorotelomer sulfonamide alkylbetaine (6:2 FTAB), and a link between the trade name and the exact chemical structure is presented here to the scientific community for the first time. In the present work, the structure of the 6:2 FTAB was elucidated by ¹H, ¹³C and ¹⁹F nuclear magnetic resonance spectroscopy and high-resolution mass spectrometry. Moreover, its major metabolites from blue mussel (Mytilus edulis) and turbot (Scophthalmus maximus) and its photolytic transformation products were identified. Contrary to what has earlier been observed for PFOS, the 6:2 FTAB was extensively metabolized by blue mussel and turbot exposed to Forafac®1157. The major metabolite was a deacetylated betaine species, from which mono- and di-demethylated metabolites also were formed. Another abundant metabolite was the 6:2 fluorotelomer sulfonamide. In another experiment, Forafac®1157 was subjected to UV-light induced photolysis. The experimental conditions aimed to simulate Arctic conditions and the deacetylated species was again the primary transformation product of 6:2 FTAB. A 6:2 fluorotelomer sulfonamide was also formed along with a non-identified transformation product. The environmental presence of most of the metabolites and transformation products was qualitatively demonstrated by analysis of soil samples taken in close proximity to an airport fire training facility.     

Ecology, management and monitoring of grey dunes in Flanders

Grey dunes are a priority habitat type of the European Union Habitats Directive and demand special attention for conservation and management. Knowledge of the ecology of coastal grey dunes can contribute to this policy. Dune grassland succession is initiated by fixation and driven by the complex of soil formation (humus accumulation) and vegetation development. Leaching and mobilization of CaCO₃. which are important in nutrient dynamics, complicate the picture. At present, grass- and scrub encroachment greatly overrules these fine scaled soil processes and causes substantial loss of regional biodiversity. Belgium has an international responsibility in grey dune conservation because of the limited range of its characteristic vegetation, flora and fauna. As biomass removal seems essential in grassland preservation, grazing is an important management tool. Evaluation of management measures focuses on biodiversity measurements on the levels of landscape, community and species.     

Lessons from Białowieża Forest on the history of protection and the world's first reintroduction of a large carnivore

Understanding how the relationships between large carnivores and humans have evolved and have been managed through centuries can provide relevant insights for wildlife conservation. The management history of many large carnivores has followed a similar pattern, from game reserved for nobility, to persecuted pests, to conservation targets. We reconstructed the history of brown bear (Ursus arctos) management in Bia?owie?a Forest (Poland and Belarus) based on a detailed survey of historical literature and Russian archives. From the end of the Middle Ages to the end of 18th century, the brown bear was considered “animalia superiora” (i.e., game exclusively reserved for nobility and protected by law). Bears, also a source of public entertainment, were not regarded as a threat. Effective measures to prevent damages to traditional forest beekeeping were already in practice. In the beginning of 19th century, new game‐management approaches allowed most forest officials to hunt bears, which became the primary target of hunters due to their valuable pelt. This, together with an effective anticarnivore policy enhanced by bounties, led to bear extirpation in 1879. Different approaches to scientific game management appeared (planned extermination of predators and hunting levels that would maintain stable populations), as did the first initiatives to protect bears from cruel treatment in captivity. Bear reintroduction in Bia?owie?a Forest began in 1937 and represented the world's first reintroduction of a large carnivore motivated by conservation goals. The outbreak of World War II spoiled what might have been a successful project; reproduction in the wild was documented for 8 years and bear presence for 13. Soft release of cubs born in captivity inside the forest but freely roaming with minimal human contact proved successful. Release of captive human‐habituated bears, feeding of these bears, and a lack of involvement of local communities were weaknesses of the project. Large carnivores are key components of ecosystem‐function restoration, and site‐specific histories provide important lessons in how to preserve them for the future.     

Assessment of aquatic experimental versus predicted and extrapolated chronic toxicity data of four structural analogues

The present study was developed to assess the chronic toxicity predictions and extrapolations for a set of chlorinated anilines (aniline (AN), 4-chloroaniline (CA), 3,5-dichloroaniline (DCA) and 2,3,4-trichloroaniline (TCA)). Daphnia magna 21 d chronic experimental data was compared to the chronic toxicity predictions made by the US EPA ECOSAR QSAR tools and to acute-to-chronic extrapolations. Additionally, Species Sensitivity Distributions (SSDs) were constructed to assess the chronic toxicity variability among different species and to investigate the acute versus chronic toxicity in a multi-species context.Since chlorinated anilines are structural analogues with a designated polar narcotic mode of action, similar toxicity responses were assumed. However, rather large interchemical and interspecies differences in toxicity were observed. Compared to the other three test compounds, TCA exposure had a significantly larger impact on growth and reproduction of D. magna. Furthermore, this study illustrated that QSARs or a fixed ACR are not able to account for these interchemical and interspecies differences. Consequently, ECOSAR was found to be inadequate to predict the chronic toxicity of the anilines and the use of a fixed ACR (of 10) led to under of certain species. The experimental ACRs determined in D. magna were substantially different among the four aromatic amines (ACR of 32 for AN, 16.9 for CA, 5.7 for DCA and 60.8 for TCA). Furthermore, the SSDs illustrated that Danio rerio was rather insensitive to AN in comparison to another fish species, Phimphales promelas. It was therefore suggested that available toxicity data should be used in an integrative multi-species way, rather than using individual-based toxicity extrapolations. In this way, a relevant overview of the differences in species sensitivity is given, which in turn can serve as the basis for acute to chronic extrapolations.     

Catalytic destruction of PCDD/F in a fabric filter: experience at a municipal waste incinerator in Belgium

In order to comply with dioxin and furan (PCDD/F) emission regulations in Belgium, the IVRO municipal waste incinerator adopted catalytic filters for use in the plant's two existing fabric filters. This system replaced the injection of powdered activated carbon (PAC) because of concerns that PAC, used at temperatures above 200 degrees C, would ignite and lead to fires and plant down-time. The performance of the catalytic filter system, since its installation in 1997, is described. PCDD/F emissions are controlled to well below the regulatory limit of 0.1 ng I-TEQ/Nm3. The amount of PCDD/F entering and exiting the fabric filter is quantified. The resulting mass balance shows that greater than 99.5% of the gaseous PCDD/F entering the fabric filter is destroyed by the catalyst within the filter media.     

Toward design principles for joint knowledge production projects: lessons from the deepest polder of The Netherlands

In various countries, actors try to reconcile climate science and policy through joint knowledge production (JNP). While many conceptual analyses of JNP exist, empirical studies that actually try to assess JNP processes are rare. This paper aims to fill this gap through an empirical analysis of the ‘Hotspot Zuidplaspolder’ project in which scientists, policymakers and other actors collaboratively looked for ways to ‘climate proof’ existing plans for urban development in one of the deepest polders of the Netherlands. The analysis is done by identifying and explaining the credibility and salience of the knowledge produced as well as the perceived legitimacy of the JNP process. Seven success factors derived from existing literature were used in the analysis. Stakeholders appeared to evaluate this project as positive, but the analysis shows that criteria and thresholds regarding success differ between the actors involved. We found three underlying design principles that should be followed to enhance the success of future JNP projects. First, it is necessary to organize several instances for reflection on the project processes. Second, new reward structures are needed to stimulate actors to take new initiatives and come up with creative ideas. Third, projects and programs should provide room to make mistakes and learn from them. This first set of empirical design principles for JNP is useful but should be further refined and nuanced in order to better deal with the social complexity of climate change and other wicked problems.     

Salinity effects on the coexistence of cryptic species: a case study on marine nematodes

The coexistence of four cryptic species of Rhabditis (Pellioditis) marina (Nematoda: Rhabditidae) at small geographical scale challenges ecological competition theory and was therefore studied in the laboratory at two different salinities, where their performance in combined cultures was compared with that in monospecies cultures. We found that three of the four cryptic species were able to coexist, but that interspecific interactions (competition and facilitation) were common. Salinity had an effect on these interactions, with a shift from contest to scramble competition. This shift may result from an increased population development of two of the four species at the lower salinity in the monospecific cultures. This experiment demonstrates that abiotic conditions may play an important role in achieving coexistence between cryptic species and can alter the interspecific interactions between them.