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Liebe Leserin, lieber Leser, bereits fünf Jahre ist es her, dass wir uns in Vögel in Deutschland ... more Liebe Leserin, lieber Leser, bereits fünf Jahre ist es her, dass wir uns in Vögel in Deutschland mit der Vogelschutzrichtlinie der Europäischen Union, damals aus Anlass ihres 30-jährigen Bestehens, näher befassten. Schon seinerzeit war klar, dass dem formalen Schritt der -nach Einstellung des Vertragsverletzungsverfahrens 2001/5117 -ebenfalls 2009 abgeschlossenen Ausweisung von Europäischen Vogelschutzgebieten in Deutschland Taten folgen müssen. Höchste Priorität war und ist dabei der Umsetzung konkreter Naturschutzmaßnahmen in den Schutzgebieten beizumessen. Aber auch die Erhaltung der Vogelbestände außerhalb der gemeldeten Gebiete durch Artenhilfsprogramme und integrierte Schutzinstrumente, wie sie beispielsweise in der Gemeinsamen Agrarpolitik der EU vorgesehen sind, ist zwingend erforderlich.

Wahl, J., J. Blew, S. Garthe, K. Günther, J. Mooij & C. Sudfeldt (2003): Waterbirds wintering in ... more Wahl, J., J. Blew, S. Garthe, K. Günther, J. Mooij & C. Sudfeldt (2003): Waterbirds wintering in Germany – trends and population estimates for 1990-2000. Ber. Vogel-schutz 40: 91-103. In 1994 BirdLife International published " Birds in Europe – their conservation status " (TUCKER & HEATH 1994). This comprehensive overview on trends and numbers of bird populations in Europe is currently under revision and will be published in 2004. This time also trends and estimates (as minimum-maximum range) for wintering populations on a national level will be included, which are presented here for 70 species wintering in Germany (incl. the Exclusive Economic Zone). 16 species declined between 1990 and 2000, 4 were regarded as stable, 16 as fluctuating (> 20% interannual fluctuation) and 5 showed an increase in population size. For 28 species no information on trends is available. Trends and numbers in some species were heavily influenced by the two consecutive cold winters 1995/1996 ...

European journal of biochemistry / FEBS, Jan 13, 1990

The coordination sphere of the two metal-binding sites/subunit of the homotetrameric D-xylose iso... more The coordination sphere of the two metal-binding sites/subunit of the homotetrameric D-xylose isomerase from Streptomyces rubiginosus has been probed by the investigation of the Co2(+)-substituted enzyme using electronic absorption, CD and magnetic circular dichroic spectroscopies in the visible region. The spectrum of the high-affinity site (B site) has an absorption coefficient, epsilon 545, of 18 M-1 cm-1, indicating a distorted octahedral complex geometry. The spectrum of the low-affinity site (A site) shows two absorption maxima at 505 nm and 586 nm with epsilon values of 170 M-1 cm-1 and 240 M-1 cm-1, respectively, which indicates a distorted tetrahedral or pentacoordinated complex structure as also observed for the enzyme from Streptomyces violaceoruber [Callens et al. (1988) Biochem. J. 250, 285-290] having the same feature but lower epsilon values. The first 4 mol Co2+ added/mol apoenzyme occupy both sites nearly equally. Subsequently the Co2+ located in the A site slowly m...

European Journal of Biochemistry, 1991

The two metal-binding sites of the D-XylOSe isomerase from Streptomyces rubiginosus were studied ... more The two metal-binding sites of the D-XylOSe isomerase from Streptomyces rubiginosus were studied using VOz + as a sensor for the ligand environment. Titration of the tetrameric enzyme with VOZf, followed by EPR spectroscopy and inhibition studies, show that the first four V 0 2 + equivalents occupy, in analogy to Co2+, Cd2+ and PbZ+, the binding site B. The visible absorption data and the EPR parameters indicate that a nitrogen ligand is involved in the ligand sphere of the high-affinity B site. The low-affinity A site could be studied selectively by blocking the B site with visible and EPR-silent Cd2 ' . The visible data and EPR parameters for this site are

European Journal of Biochemistry, 1993

The two metal-binding sites (A and B)/subunit of the homotetrameric D-xylose isomerase (Xyl isome... more The two metal-binding sites (A and B)/subunit of the homotetrameric D-xylose isomerase (Xyl isomerase) from Streptomyces rubiginosus have been studied with MnZ+-EPR spectroscopy at Xband and Q-band frequencies and with electronic spectroscopy. Displacement studies in the visible absorbance range showed that Mn2+ have a higher affinity for the B site. With the low-affinity A site unoccupied, the coordination sphere of MnZ+ in the B site is quite distorted giving rise to a highly anisotropic X-band EPR spectrum. Simulation of the Q-band spectrum reveals a zero field splitting (zfs) D of about 45-48 mT and a rhombicity parameter EID between 0.2 and 0.3. Occupation of both binding sites with Mn2+ induces a significant shift towards a higher symmetry in the coordination sphere of the B site resulting in similar zfs parameters for both binding sites. The change in A-site environment caused by B-site occupation was analysed in mixed Xyl isomerase derivatives, in which the B site is loaded with Co2+, Cd2+ or Pb2+ and the A site with Mn2+. In the Co2+/Mn2+ Xyl isomerase the Mn2+ has a relatively symmetric ligand environment with small zfs parameters ( D = 12 mT, EID < 0.15). Substituting Co2+ with Cd2+ or Pb2+ in the B site leads to a drastic increase in the zfs parameters of Mn2+ in the A site. The distortions are directly linked to the ionic radii of the ions bound to the B site and may be mediated by the carboxylate group of Glu216 that bridges the metal-binding sites. The EPR spectra also reflect the catalytic activity of the mixed metal samples. With the larger Cd2+ or Pb2+ in the B site, which are strongly influencing the stereochemistry of the A site, the catalytic activity is lost, whereas Co2+ and Mn2+ render the enzyme in an active state, so that the mutual influence on catalysis depends on the complex geometry of both metal-binding sites. D-Xylose isomerase (Xyl isomerase) from Streptomyces rubiginosus catalyses in vivo the reversible isomerisation of D-xylose to D-xylulose. It also converts D-glucose to D-fructose, a reaction widely used in industrial processes [l, 21. The reactive anomers of the substrates of Xyl isomerase are the a-D-pyranose forms of D-xylose and D-glucose [3-51 and the a-D-furanose forms of D-fructose . The enzyme exists as a tetramer of identical subunits. The activity of Xyl isomerase is generally dependent on the presence of bivalent cations. The enzymes of Streptomyces species are best activated by Mg". Partial activity is reached after addition of Co2+, Mn" or Fe2+ [7-111. Addition of Zn2+, Cd", or Pb" to the metal-free apoenzyme does not restore activity. However, their addition in the presence of saturating Mg2+ concentrations inhibits the enzyme almost completely .

As part of the fi rst pan-European Cormorant midwinter census Great Cormorants were counted at th... more As part of the fi rst pan-European Cormorant midwinter census Great Cormorants were counted at their night roosts in Germany in mid-January 2003. A total of 500 roosts were controlled (including 158 unoccupied roosts/waterbodies). In neighbouring countries close to the German border another 18 roosts were checked (two of which did not hold birds). Within Germany 33,568 Cormorants were recorded. Accounting for about 10% of the individuals being missed during the census, the total German midwinter population was estimated at c. 38,000 birds in January 2003. Compared to counts in the western federal states in the mid 1990s, numbers increased only slightly. However, the number of roosts rose by at least 25% in this region. Due to the low temperatures in the fi rst half of January 2003, most water bodies in northern and eastern Germany were covered with ice. In these regions large roosts formed on the coast. Almost half (47%) of the night roosts held up to 50 birds, and only about 13% mo...

Journal of Ornithology, 1982

Die Brutbiologie des Wiesenpiepers war bereits Gegenstand mehrerer Untersuchungen (z. B. CoutsoN ... more Die Brutbiologie des Wiesenpiepers war bereits Gegenstand mehrerer Untersuchungen (z. B. CoutsoN 1956, DAVIES 1958, PULLiAINEN 1977. Hier soll nun der Versuch gemacht werden, Daten zur Länge der Brutsaison, Anzahl der Bruten, Gelegegröße und zum Bruterfolg einer zum Teil individuell markierten Population in Nordwestdeutschland mit den Literaturangaben zu vergleichen.

Journal of Ornithology, 1979