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91.
Zusammenfassung Eier von Sperbern aus Brandenburg und aus Nordhrein-Westfalen wurden auf ihren Gehalt an PCB, DDT, HCH, HCB und die Schwermetalle Blei und Cadmium untersucht. Bei den PCB und beim DDT und seinen Abbauprodukten traten signifikante Unterschiede in der Belastung der beiden Populationen auf, während die anderen untersuchten Stoffe in den Eiern beider Untersuchungsgebiete nur in geringen Mengen nachzuweisen waren. Dabei waren in den Proben aus der ehemaligen DDR die DDT-Konzentrationen deutlich höher als in den Eiern aus dem westfälischen Münsterland. Bei den PCB-Konzentrationen ergab sich ein genau umgekehrtes Ergebnis, im Münsterland waren diese erheblich höher. Die Ergebnisse stehen im klaren Zusammenhang mit der unterschiedlichen Anwendung und dem zeitlich unterschiedlich erfolgtem Verbot der untersuchten Schadstoffe in den beiden ehemaligen deutschen Staaten. Trotz der Belastungsunterschiede bezüglich der PCB ist das PCB-Muster in den Eiern aus den Untersuchungsgebieten aufgrund des artspezifischen Metabolismus nahezu identisch.
Comparison between the burden of xenobiotics in eggs of the Sparrowhawk (Accipiter nisus) from Brandenburg and North-Rhine-Westphalia, Germany
Summary Eggs from Sparrowhawks from Brandenburg (former GDR) and North-Rhine-Westphalia (former FRG) were examined for their burden of PCB, DDT, HCH, HCB and the heavy metals lead and cadmium. Significant differences emerged in the cases of PCB and DDT and its metabolites between the populations of the two regions. The other examined xenobiotics were detectable only in low concentrations. The DDT concentrations were distinctly higher in the samples from the former GDR, while PCB concentrations were higher in the eggs from North-Rhine-Westphalia. The results reflect clearly the different use and prohibition of the examined xenobiotics in the two former german states. In spite of the differences in the PCB burden, the PCB pattern in the eggs of the different regions is nearly identical. Eggshell indices correlate negatively with DDT burden in both sample areas.
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92.
德国人文聚落区生态单元制图国家项目   总被引:5,自引:0,他引:5  
联邦德国自然保护法、德国各州自然保护法要求在自然景观区和人文聚落区保护、管理和发展自然。实现这一法律要求 ,必须以现实的、全面的、高质量的、与自然保护原则相匹配的数据为基础。实践证明 ,城乡生态单元制图是获取和解释这些数据不可或缺的手段。德国人文聚落区生态单元制图始于 1 978年 ,同年组建成立了德国联邦与各州自然保护部门参加并联合协调的“人文聚落区生态单元制图工作组”。 1 986年工作组提出了德国人文聚落区生态单元制图基本方案 ,1 993年完成基本方案修订版。基本方案的目标是在全国范围建立标准制图方法 ,使获取的科学数据可以相互比较。至 2 0 0 0年 ,德国在人文聚落区生态单元制图项目上的投资约合 2亿马克 ;至 2 0 0 1年 3月 ,德国有 2 2 3个大中城市已经完成或正在实施生态单元制图 ,人文聚落区生态单元制图已经成为德国各级政府生态规划的基本工作内容。  相似文献   
93.
Summary

Titers of juvenile hormone III and methyl farnesoate, its unepoxidized precursor, were measured throughout embryonic development using a gas-chromatographic method and it was revealed that both substances are undetectable before dorsal closure. Thereafter they both reach similarly high concentrations (800 ng/g) until a few days before hatching, when their titers begin to decrease. Application of the precocene analogue, 7-ethoxy-6-methoxy-2,2-dimethyl-chromene, to egg-cases at dorsal closure results in very low or undetectable titers of juvenile hormone III, depending on the dose applied, whereas methyl farnesoate is seen to reach high levels similar to those seen in the controls. The severe developmental disturbances observed suggest that juvenile hormone III is very important for normal development and formation of the 1st instar larva.  相似文献   
94.
ABSTRACT The knockdown and lethal efficacies of five aerosol formulations including Combat Speed® (AIs: 0.1 % imiprothrin and 0.3% cyphenothrin), Raid Power® (AIs: 1.0% pyrethrin and 0.2% permethrin), Home Keeper®, (AIs: 0.2% tetramethrin and 0.3% permethrin), Super Killer® (AIs: 0.32% tetramethrin and 0.08% bioresmethrin), and Perma Kill‐K® (AIs: 0.3% dichlorvos and 0.1% tetramethrin) against five strains of the German cockroach, Blattella germanica (L.) were assessed. The results show that the mean value of KT50 (5.4 sec.) of Combat Speed® was 4.5 and 3.1‐folds lower than those of Perma Kill‐K® and Home Keeper®, respectively. The mean value of KT90 (9.0 sec; slope = 10.02) of Combat Speed® was 3.8 to 5.8‐folds lower than Perma Kill‐K®, Supper Killer® and Home Keeper®. As lethal effects, the mean value of LT50 (17.3 sec.) of Combat Speed® was over 26 folds lower than Supper Killer® and Perma Kill‐K®. The mean value of LT90 (32.9 sec.) of Combat Speed® was 37.4 and 15.1‐folds lower than those of Supper Killer® and Perma Kill‐K®, respectively. In general, Combat Speed® and Raid Power® were considered the insecticide aerosols with faster knockdown and higher lethal effects than Supper Killer®, Perma Kill‐K®, and Home Keeper® against five strains of German cockroaches in Korea. Also, the knockdown and lethal effects of Supper Killer®, Perma Kill‐K®, and Home Keeper® were highly variable depends on the strains.  相似文献   
95.
Insecticide resistant and susceptible field-collected strains of the German cockroach were surveyed for the occurrence of chromosome polymorphisms. Analyses were on meiotic cells of males that hatched from oothecae with unusual numbers (>5) of incompletely developed eggs (aberrant oothecae). Three males were reciprocal translocation heterozygotes. A spontaneous translocation was noted in one cell of a fourth male. The males were from insecticide resistant strains. Partially developed eggs in oothecae from outcrosses of two of the translocation herozygotes ceased development in early stages and were characterized by gross morphologic abnormalities. Chromosome abnormalities other than translocations occurred in a low percentage of males from aberrant oothecae in both resistant and susceptible strains. The only general differences between susceptible and resistant strains were that, in pooled data, the frequencies of unhatched oothecae and of aberrant oothecae were higher in the resistant than susceptible strains.  相似文献   
96.
Glucose aversion(Glu) is a naturally occurring behavioral mutant of the German cockroach,Blattella germanica. Earlier work suggested thatGlu is a semidominant autosomal trait. Further study was undertaken to place the mutant gene in the linkage map of the species and expand the information on its genetic basis. Linkage was investigated in test crosses with morphologic markers for 7 of the 11 autosomal linkage groups. Assays for amounts of glucose ingested per individual confirmed the expected low consumption ofGlu heterozygotes(Glu/+) and that continuous selection pressure on the parental strain had resulted in near- and probably complete homozygosity forGlu. Glu genotypes were identified by means of a discriminating ingestion that separated heterozygotes from wild type(Glu+). Variations in expression indicate that genetic factors influence food consumption inB. germanica. Positive results were obtained in linkage tests ofGlu with ruby eye(ru), indicating that theGlu locus lies in linkage group VIII (chromosome 9), a group notable for mutants that apparently result in the expression of latent, highly primitive development pathways.  相似文献   
97.
Allatostatins are a family of neuropeptides first isolated from the cockroach, Diploptera punctata, that inhibit juvenile hormone production in that species (but do not do so in earwigs), and inhibit hindgut muscle contractions in some insects, including the earwig, Euborellia annulipes. We examined whether material from earwig brains is similar to cockroach allatostatins biochemically, immunologically and physiologically. Brain extracts from adult female earwigs were separated by high performance liquid chromatography (HPLC), followed by radioimmunoassay using antibodies to cockroach allatostatin (Dip-AST). Fractions that co-eluted with cockroach allatostatins were immunoreactive, and at least two peaks of immunoreactivity were detected. Material from each peak at 10 nM Dip-AST equivalents inhibited juvenile hormone biosynthesis in vitro by corpora allata of 2-day virgin D. punctata cockroaches; 1 nM was less effective, and non-immunoreactive fractions failed to inhibit juvenile hormone biosynthesis. Both crude and Sep-Pak (Waters) purified extracts of brains of earwigs containing 1 nM Dip-AST equivalents failed to suppress hindgut contractions in vitro of 2-day earwigs and of brooding female earwigs. In contrast, 1 nM cockroach allostatin 1 (Dip-AST 7) reversibly inhibited hindgut contractions in vitro. These results suggested the presence of another brain factor, such as proctolin, that counteracts the inhibitory effects of Dip-AST. In support of this hypothesis, proctolin stimulated hindgut contractions in vitro at 1 nM; the effects of equal concentrations of allatostatin and proctolin varied with the stage of the female. Furthermore, HPLC-separated fractions that co-eluted with cockroach allatostatin and were immunoreactive with antibodies to Dip-AST suppressed hindgut contractions in vitro of 2-day female earwigs. Finally, crude brain extracts of earwigs suppressed earwig juvenile hormone biosynthesis in vitro in glands of low, but not in glands of high, activity. Thus, earwig brain extract after HPLC separation has Dip-AST-like material that inhibits cockroach corpora allata and suppresses earwig hindgut contractions. Sep-Pak-extracted earwig brain material, however, does not inhibit earwig gut contraction. Although synthetic Dip-AST 7 does not inhibit juvenile hormone synthesis by earwig corpora allata, there is heat-stable material in earwig brain extract that does have this action.  相似文献   
98.
Six charophyte, 13 mollusc, four ostracod and nine fish otolith taxa are taxonomically described, and one fruit, one seed and two foraminiferal taxa are briefly noted from the Lower Cyrena Beds and the Lower Coloured Molasse of the Sindelsdorf section near Penzberg (approximately 50 km south of Munich). Our palaeoecological and lithological data from the Lower Cyrena Beds suggest a delta plain with lagoons, estuaries, slowly flowing rivers, lakes and swamps. Faunal and floral elements of the Lower Coloured Molasse indicate lacustrine environments. The gastropod Tympanotonos and the tropical to subtropical fish fauna (Eleotridae, Ambassidae and Cyprinodontidae) suggest a warm, at least subtropical climate. Furthermore, Tympanotonos suggests comparisons with Recent molluscan faunas of the mangrove swamps of the West African coast, and thus hints at mangrove vegetation bordering the coasts of the Upper Bavarian Molasse Sea. A biostratigraphical classification for the Oligocene Molasse deposits of the Penzberg Syncline is established for the first time based on otoliths and charophytes. The Lower Cyrena Beds are attributed to the newly defined otolith zone OT-O1/2 and probably correspond to the oldest part of the Chara microcera Zone. The lowermost part of the Lower Coloured Molasse can be correlated both with otolith zone OT-O2 and the Chara microcera Zone. The Sindelsdorf section lies within the Rupelian–Chattian transition zone and thus the chronostratigraphic age is approximately 29–28 Ma.  相似文献   
99.
Zusammenfassung Zwischen 1825 und 1828 versuchte Christian Ludwig Brehm (1787–1864) eine Vollständige Naturgeschichte der europäischen Vögel, illustriert von seinem Freund Friedrich Wilhelm Justus Baedeker (1786–1865), herauszubringen. Brehms Bemühungen um eine Förderung des Tafelwerk-Projektes durch den preußischen König Friedrich Wilhelm III scheiterten an einem Gutachten Hinrich Lichtensteins. Ein bislang unbekannter Brief von Brehm mit einem Originalaquarell Baedekers ergänzt und erweitert unser Wissen um dieses erfolglose Buchvorhaben.
A complete natural history of the European birds by Christian Ludwig Brehm and Friedrich Wilhelm Justus Baedeker
Summary Between 1825 and 1828, Christian Ludwig Brehm tried to publish a Complete natural history of the European birds illustrated with plates by his friend Friedrich Wilhelm Justus Baedeker (1786–1865). Brehm's efforts to get this project supported by the Prussian king Friedrich Wilhelm III. failed as a result of an expertise by Hinrich Lichtenstein. A so far unknown letter written by Brehm with an enclosed original water-colour painting by Baedeker completes and enlarges our information on this unsuccessful book project.
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100.
A population of Blattella germanica L. (Dictyoptera) cockroaches was studied in a swimming-bath. Trapped adults were marked and released in their capture area.The overall recapture rate was 15%, but it varied according to the capture area. This rate was higher in the toilets than around the pool borders. Distances between capture and recapture points also varied. Recaptures were more frequent in the capture area than in other areas; only 15% of the animals left their initial area. Movements occurred mainly between neighbouring areas. Recaptures in the capture area were lower around the large pool than around the shallow pool and in the toilets.In conclusion, there were three types of areas which were differently occupied. This could be explained by variations of resources like shelter and food. The complexity of the environmental structure favoured development of cockroach populations although they were able to modify their behavior in relation to the environmental features.
Résumé Une population de Blattes (Blattella germanica) a été étudiée dans l'enceinte d'une piscine par des piégeages hebdomadaires. Les animaux adultes sont marqués et relachés dans leur zone de capture initiale.Le taux de recapture total est de 15%; mais on observe des differences en fonction de la zone de capture. Le taux de recapture est plus élevé dans les toilettes qu'en bordure des bassins. Par contre les distances entre capture et recapture y sont plus faibles.D'autre part, le taux de recapture est plus élevé dans la zone de capture initiale: seulement 15% des animaux changent de zone. Les déplacements ont lieu principalement entre deux zones voisines. Les recaptures dans la zone d'origine sont meilleures autour du petit bassin et dans les toilettes qu'autour du grand bassin.D'après ces résultats, il est possible de distinguer trois types de zone qui présentent un taux d'occupation plus ou moins élevé. Le taux d'occupation dans ces trois zones pourrait être lié à l'abondance des ressources telles que la nourriture et les abris. L'augmentation de la complexité de la structure du milieu qui augmente le nombre d'abris potentiels semble favoriser le développement des populations de Blattes. Celles-ci sont cependant capables d'adapter leur comportement avec les caractéristiques du milieu et de l'exploiter au mieux.
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