Corticosterone levels in relation to migratory readiness in red-eyed vireos (<Emphasis Type="Italic">Vireo olivaceus</Emphasis>)

We examined the relationship between plasma levels of corticosterone and the migratory activity and directional preference of red-eyed vireos during fall migration at the northern coast of the Gulf of Mexico. Corticosterone is thought to play a role in physiological and behavioural processes before, during, and after long-distance migratory flights. An increase in corticosterone at the onset of migratory flights can be expected in birds that are energetically prepared to migrate in a seasonally appropriate southerly direction. Red-eyed vireos ( Vireo olivaceus) were tested in orientation cages under clear twilight skies. Just prior to the orientation experiments, blood was sampled to assay baseline corticosterone levels. Average corticosterone level for all birds was 22.8 ng/ml. Red-eyed vireos with higher than average baseline levels of corticosterone were significantly more active in orientation cages compared to birds with lower levels of corticosterone. Moreover, birds with higher than average levels oriented in a southwesterly direction, which is consistent with a trans-Gulf flight, whereas individuals with levels below average showed a NNW mean direction. Although there was no significant difference in baseline levels of corticosterone between fat and lean birds, individual mass loss between capture and test was negatively correlated with corticosterone levels. Results from this study clearly demonstrate that corticosterone influences departure decisions and the choice of direction during migration.     

II. Aufbau fl?chenrepr?sentativer Probenahmen von Umweltproben zur Schadstoffanalytik am Beispiel der Regenwürmer in landwirtschaftlich genutzten R?umen

Ein sinnvoller Einsatz von Akkumulationsindikatoren erfordert zur Qualit?tssicherung neben den vorhandenen Laborstandards ein anspruchsvolles Probenahmeverfahren, um repr?sentative und reproduzierbate Aussagen über einen Untersuchungsraum treffen zu k?nnen. Am Beispiel der Regenwürmer wird exemplarisch ein Probenahmeverfahren für landwirtschaftliche R?ume entwickelt und vorgeführt. Erste Ergebnisse der in den Wurm- und Kotproben gemessenen polyzyklischen aromatischen Kohlenwasserstoffe, der chlorierten Kohlenwasserstoffe und der Elemente werden dargestellt. Die Schadstoffgehalte der vergleichbaren Wurmproben belegen, da? es die repr?sentative Probenahmestelle in einem Untersuchungsgebiet nicht gibt. Die Heterogenit?t des Untersuchungsraumes kann nur durch eine geschichtete Zufallsstichprobe mit einer ausreichenden Anzahl von Einzelproben erfa?t werden.     

Biocompatibility correlation of polymeric materials using human osteosarcoma cells

 Metal implants are the preferred materials to generate articular prostheses, plates, or bone pegs in orthopedic surgery. Although titanium and titanium alloys show a relatively good biocompatibility, clinical experience revealed that coating of the metallic implant surface may increase the biocompatibility. In a search for optimum bone implant surfaces, we determined polarity and contact angle parameters of a variety of polymers and substances and correlated the findings in a biocompatibility assay using an in vitro bone cell model. We report that an optimum adherence of SAOS-2 cells to such surfaces and a good vitality for polymers are characterized by water-based contact angles of 80° and 20° for advancing and receding probes, respectively. Received: 18 October 1999 / Accepted in revised form: 19 April 2000     

Trend der Schwermetall-Bioakkumulation 1990 bis 2005: Qualitätssicherung bei Probenahme, Analytik, geostatistischer Auswertung

Background, aim and scope Since 1990, the UN ECE Heavy Metals in Mosses Surveys provide data inventories of the atmospheric heavy metal bioaccumulation across national boundaries in Europe. The results prove how air pollution control in Germany and in all of Europe affected the bioaccumulation of metals in those ecosystems that are not directly influenced by nearby emission sources. This article focuses on the assessment of spatiotemporal patterns of the metal bioaccumulation in Germany since 1990. Furthermore, the spatial variance of the metal bioaccumulation is analysed with regard to sampling site-specific and regional land characteristics. Special focus hereby relies on the correlation of the metal concentration in mosses and in depositions. Hence, the moss surveys contribute to §?12 of the German Federal Nature Conservation Act as well as to the “Convention on Long-range Transboundary Air Pollution” (CLRTAP). Materials and methods The bioaccumulation of up to 40 trace elements in mosses was determined according to a European wide harmonised methodology. The according experimental protocol regulates the selection of sampling sites and moss species, the chemical analysis and quality control and the classification of the measured values for the mapping of spatial patterns. In Germany all sampling sites were described with regard to topographical and ecological criteria as well as other aspects seen as relevant in the mandatory guideline. Together with the measurements this metadata was combined with other information regarding emissions and land use in the surroundings of the sampling sites in the WebGIS MossMet. The spatial structure of the metal bioaccumulation was analysed and modeled by variogram analyses and then mapped by applying different kriging techniques. Furthermore, different multi-metal indices (MMI) were derived for both the sampling sites and raster maps with the help of percentile statistics: The MMI1990 aggregates the data for Cr, Cu, Fe, Ni, Pb, Ti, V and Zn determined in 1990. The MMI1995, MMI2000, MMI2005 furthermore include As, Cd, Hg and Sb for 1995, 2000 and 2005, respectively. Two other MMI allow for a time integrating view on the metal bioaccumulation in Germany: The MMI1990–2005 was calculated on behalf of all measured/geostatistically estimated data for Cr, Cu, Fe, Ni, Pb, Ti, V and Zn. Therefore the integrated assessment of the metal bioaccumulation in Germany from 1990 to 2005 is possible. The MMI1995–2005 furthermore includes the element-specific data of As, Cd, Hg and Sb therefore integrating 12 elements over the last three surveys. The statistical association of the metal bioaccumulation, site-specific characteristics as well as information on land use and emissions was analysed by bivariate correlation analysis and multivariate decision tree models (Classification and Regression Trees – CART, Chisquare Automatic Interaction Detection – CHAID). Results The results of the quality-controlled chemical analyses show a significant decrease of the metal bioaccumulation in Germany from 1990 to 2000. From 2000 to 2005 a further decrease can be stated for Hg, Pb and Ti. However, a significant increase for Cd, Cr, Cu, Sb and Zn can be observed. This especially holds true for Cr (+ 160?%) that almost reaches as high concentrations in mosses as in 1990. In 2005, the metal loads in mosses, except for Cr, show spatial distributions similar to those in 1990, 1995 and 2000. Hot spots are mostly found in the urbanised and industrially influenced Ruhr Area, the densely populated Rhine–Main region and in the industrially influenced regions of former East Germany (e.?g. Halle–Leipzig region). The spatial variance of the metal bioaccumulation can mainly be explained by site-specific (moss species, canopy drip effects) and site-surrounding (land use, depositions, emissions) characteristics. Discussion High Cr loads in mosses were also registered in other European countries like in Switzerland. Further investigation is therefore necessary to investigate whether this is due to different emission conditions or biogenic effects (e.?g. as a result of increasing nitrogen depositions). Compared to other environmental monitoring and modelling programmes the moss surveys registered increasing concentrations of toxic metal elements between 1990 and 2005. Contrary to deposition measurements that exhibit a higher temporal resolution the moss surveys provide measurement data on a wide range of elements. Some of these elements are important with regard to human-toxicological aspects (e.?g. Hg, Sb, As, Al, V). The standardised biomonitoring of atmospheric pollution by mosses is an important link between the technical acquisition of depositions and the accumulation in biological material. To claim that the element concentrations in mosses and in the deposition should correlate to a high degree is not appropriate since both approaches are physically related but are not identical. The degree of correlation thereby depends on the boundary conditions of the physical processes, like regional and site-specific meteorological conditions within the accumulation period, the vertical and horizontal vegetation structure or land use conditions. Conclusions The moss surveys contribute to the heavy metal and multi-component model of CLRTAP because they prove on different spatial scales how air pollution control influences the accumulation of emitted substances in environmental subjects of protection like vegetation. If environmental monitoring is seen as a continuous task and the applied methodology works well as an early warning system then environmental policy is enabled to act in preventative sense and to pursue unexpected developments. No other environmental monitoring programme provides such a wide range of ecotoxically relevant elements measured as spatially dense as the case for the moss surveys. The spatial distribution of environmental information is an essential criterion for their usability in terms of political measures for the federal states and the federation. Recommendations and perspectives The Heavy Metals in Mosses Surveys are a positive example for environmental monitoring activities reaching across three spatial and administrative levels: regional (e.?g. federal state or natural landscape), nationwide (e.?g. Germany) and continental (e.?g. Europe). In Germany the harmonised and quality-controlled moss data are made available via an internet-based webGIS portal. Therefore the moss data may easily be accessed for environmental monitoring purposes and the control of environmental political actions. Hence, the monitoring of Heavy Metals by Mosses Surveys is an important task among the European environmental observations, which should be continued in future for scientific and political reasons in its current extent.     

Klimawandel und zukünftig mögliche temperaturgesteuerte Malariatransmission in Deutschland

Background, aim and scope On behalf of the Centre of Excellence for Climate Effects and Adaption (KomPass) of the German Federal Environment Agency (UBA) an Expert Information System on Climate Change and Adaption (FISKA) was developed. FISKA shall provide the governmental institutions with basic information and models on climate change impacts for the development and accomplishment of adaption strategies. In this paper the impact model on potential temperature-dependent malaria transmissions is presented. It shows how, together with the REMO and WettReg climate models implemented in FISKA, areas at risk of malaria can be identified. Materials and methods FISKA was developed as an open and modular expert information system and allows the exchange of data and information with other institutions. Climate change impacts are implemented as calculation engines. The system allows for implementing additional data and impact models to improve existing impact models. For the calculation of the temperature-dependent potential secondary malaria infections the basic reproduction rate was used and the according algorithms were implemented in two calculation engines. One engine allows the calculation of the secondary infections and the other allows the calculation of the seasonal transmission gates. Measured air temperatures for the period 1961–2007 were provided by the German Meteorological Service (DWD), data on future air temperatures were extracted from the climate models REMO and WettReg for the climate reference periods 1991–2020, 2021–2050, and 2051–2080. The respective secondary infections and the resulting seasonal transmission gates for each period were regionalised on the basis of an ecological land classification to analyse significant ecoregional differences. Results Comparing the climate reference period 1961–1990 and the following period 1991–2007, the proportion of Germany featuring a potential seasonal malaria transmission gate of one or rather two months has been reduced in favour of a three months transmission gate. Accordingly, in the period 1991–2007 malaria transmissions during three months are possible on 70?% of the German territory instead of 26?% in 1961–1990. The percentage of a four months transmission gate has increased from 0.02?% to 0.76?%, and even a five months transmission is possible on 0.15?% of Germany. For future periods the number of potential secondary infections increases and further extensions of the seasonal transmission gates were revealed. In case of REMO A1B in 2051–2080, almost whole Germany features thermal conditions allowing malaria transmissions during four or rather five months. Discussion Rising air temperatures lead to changes in the spatial structure of the ecological elementary factor temperature, which can, under otherwise identical conditions, facilitate the reproduction of pathogens (here Plasmodium vivax) and vectors (here Anopheles atroparvus) as well as the spread of diseases. The basic reproduction rate serves the calculation of secondary malaria infections, which are the infections of host by a vector under the assumption that every member of the host population is susceptible for the pathogen. Improved thermal conditions alone do not necessarily imply the development of a malaria epidemic. Other factors like population density or medical care and the presence of vector habitats are of major importance, however, not considered by the calculation engines. The example of malaria is intended to be a model for a range of temperature-dependent vector-borne diseases. Conclusions The impact model on temperature-dependent malaria infections shows exemplarily the information content and functionality of FISKA. Data and functionality of FISKA serve as an expert information system for the detection of risks due to climate change. The results can be published as interactive maps via the FISKA internet interface. From a technical point of view, every impact model based on a calculation engine can be implemented and published via the web interface, provided that the impact models and the resulting risk maps rely on scientific reliable assumptions and are documented comprehensively. Recommendations and perspectives An improvement of FISKA considering the European scale is technically possible. It would require the development of GIS- and model applications on the basis of Europe-wide basic and specific data. For small-scale model runs a dynamic modelling of the water balance including soil hydrology as well as consideration of microclimate effects are required.     

Spatial variability of nitrous oxide and methane emissions from an MBT landfill in operation: Strong N2O hotspots at the working face

Mechanical biological treatment (MBT) is an effective technique, which removes organic carbon from municipal solid waste (MSW) prior to deposition. Thereby, methane (CH₄) production in the landfill is strongly mitigated. However, direct measurements of greenhouse gas emissions from full-scale MBT landfills have not been conducted so far. Thus, CH₄ and nitrous oxide (N₂O) emissions from a German MBT landfill in operation as well as their concentrations in the landfill gas (LFG) were measured. High N₂O emissions of 20–200 g CO₂ eq. m^?2 h^?1 magnitude (up to 428 mg N m^?2 h^?1) were observed within 20 m of the working face. CH₄ emissions were highest at the landfill zone located at a distance of 30–40 m from the working face, where they reached about 10 g CO₂ eq. m^?2 h^?1. The MBT material in this area has been deposited several weeks earlier. Maximum LFG concentration for N₂O was 24.000 ppmv in material below the emission hotspot. At a depth of 50 cm from the landfill surface a strong negative correlation between N₂O and CH₄ concentrations was observed. From this and from the distribution pattern of extractable ammonium, nitrite, and nitrate it has been concluded that strong N₂O production is associated with nitrification activity and the occurrence of nitrite and nitrate, which is initiated by oxygen input during waste deposition. Therefore, CH₄ mitigation measures, which often employ aeration, could result in a net increase of GHG emissions due to increased N₂O emissions, especially at MBT landfills.     

Atmosphärische Deposition und Anreicherung von Schwermetallen und Stickstoff in Natura-2000-Gebieten Deutschlands

Purpose Under the Convention on Long-range Transboundary Air Pollution mosses are used to map the bioaccumulation of heavy metals and nitrogen throughout Europe. To this end, since 1990 mosses were sampled and analyzed chemically every five years. The goal of this article is to apply the moss survey data for assessing the bioaccumulation of Cd, Pb and N in German Natura 2000 Sites of Community Importance (SCI). Methods The temporal trends of the heavy metal bioaccumulation within SCIs were analyzed using a multi metal index (MMI) calculated by means of geostatistics and percentile statistics. For nitrogen, only monitoring values for 2005 were available for the assessment. The geostatistically estimated values of the metal and nitrogen concentrations in mosses were transformed to estimated deposition values by use of regression analyses. Subsequently, the results were integrated into the assessment of the German SCIs. Results Highest metal loads within SCIs were detected in 1990, followed by a continuous decrease to 2000 and a significant increase until 2005. Regarding N, a median of 1.5?% nitrogen in the dry mass was calculated. The deposition values calculated from the moss estimates resulted in median values of 0.33?g/ha/a for Cd, 8.2?g/ha/a for Pb and 16.7?kg/ha/a for nitrogen. Conclusions The Moss-Monitoring is the only environmental monitoring programme which enables statistically sound estimations of the exposure of SCI to environmental contaminants in terms of heavy metal and nitrogen deposition and bioaccumulation.