Martin-Luther-Universität Halle-Wittenberg: Elektronische Zeitschriften
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Indian Diamond Dealers in Antwerp: Patterns, Determinants, and Regional Implications of Economically Determined Transmigration
No full textThe paper aims at linking the concepts of transnational communities and regional clusters. Using the example of the Antwerp diamond district, it will be shown that its recent structural change can mainly be attributed to the influx of a transnational community, namely Jaina families from Western India. Based on the analysis of guided interviews, immigration files and secondary data, the migration patterns will be considered as an outcome of both economic growth in the transmigrants’ home region and the social structure of the community itself. Furthermore, it will be shown that the Indians contributed to closures of incumbent firms, a modification of local specialization patterns as well as to changes of the local institutional framework in the destination area
Zur Biologie und gegenwärtigen Verbreitung von Gibbium psylloides (Czempinski) (Coleoptera: Ptinidae) in der DDR
Get PDFZur Beeinflussung einiger Moosgesellschaften durch Luftverunreinigung: 26. Beitrag zur Moosvegetation Thüringens
Get PDFVeränderung der Nährstoffverhältnisse von Böden in einem Immissionsgebiet und Auswirkungen auf die Pflanze mittels eines Feldversuches
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Preliminary key to the nymphs of the families and subfamilies of the German Auchenorrhyncha fauna: (Hemiptera, Fulgoromorpha et Cicadomorpha)
Get PDFA preliminary key for identification of the nymphs of German Auchenorrhyncha to the level of family and subfamily is presented. It covers 7 families and, within Delphacidae, 4 subfamilies and within Cicadellidae, 13 subfamilies. Each group is represented by at least one species. Altogether 49 species are illustrated, with 60 additional figures of diagnostic characters.A preliminary key for identification of the nymphs of German Auchenorrhyncha to the level of family and subfamily is presented. It covers 7 families and, within Delphacidae, 4 subfamilies and within Cicadellidae, 13 subfamilies. Each group is represented by at least one species. Altogether 49 species are illustrated, with 60 additional figures of diagnostic characters
Zur Fauna der Zikaden, Blattflöhe und deren Parasitoide der Alp Flix (Graubünden, Schweiz): (Hemiptera: Auchenorrhyncha und Psylloidea; Diptera: Pipunculidae, Strepsiptera: Elenchidae)
Get PDFDuring the 13th Central European Auchenorrhnycha meeting in the Swiss Alps (Alp Flix, Grisons) in August 2006 a total of 75 Auchenorrhyncha species, 29 species of Psylloidea, 2 Pipunculidae (Diptera) species and 1 species of Strepsiptera have been collected. Together with two excursions in 2002 and 2006 a total of 86 Auchenorrhyncha species are reported from the area of Alp Flix. The four auchenorrhynchous species Kelisia sima Ribaut, Muellerianella extrusa (Scott), Aphrodes diminuta Ribaut and Zygina rubrovittata (Lethierry) are recorded here for the first time for Switzerland. One species, viz. Sonronius dahlbomi (Zetterstedt) was rediscovered after a period of more than 100 years. On exkursions in 1978, 2000, 2001, 2002 and 2003 additional psyllids were collected giving a total of 47 species recorded for Alp Flix.During the 13th Central European Auchenorrhnycha meeting in the Swiss Alps (Alp Flix, Grisons) in August 2006 a total of 75 Auchenorrhyncha species, 29 species of Psylloidea, 2 Pipunculidae (Diptera) species and 1 species of Strepsiptera have been collected. Together with two excursions in 2002 and 2006 a total of 86 Auchenorrhyncha species are reported from the area of Alp Flix. The four auchenorrhynchous species Kelisia sima Ribaut, Muellerianella extrusa (Scott), Aphrodes diminuta Ribaut and Zygina rubrovittata (Lethierry) are recorded here for the first time for Switzerland. One species, viz. Sonronius dahlbomi (Zetterstedt) was rediscovered after a period of more than 100 years. On exkursions in 1978, 2000, 2001, 2002 and 2003 additional psyllids were collected giving a total of 47 species recorded for Alp Flix
Asianidia Zachvatkin (Hemiptera, Cicadellidae) associated with the laurisilva forest of Madeira island: species phenology and hostplant preferences
Get PDFIm Rahmen einer Untersuchung zur Zikadenfauna von Lorbeerwäldern auf Madeira wurden fünf Arten der Gattung Asianidia Zachvatkin nachgewiesen: A. albula, A. decolor, A. insulana, A. chrysanthemi und A. melliferae. In Summe wurden 513 Individuen gesammelt. Die Häufigste Art war Asianidia decolor (47%), gefolgt von A. albula (36%) und A. insulana (16%). A. chrysanthemi und A. melliferae wurden nur in geringer Zahl gefangen. Die Hauptaktivität der Arten ist im Frühjahr und Sommer, A. albula und A. decolor zeigten ein weiteres Abundanzmaximum im November. Asianidia chrysanthemi und A. melliferae sind monophag, die anderen drei Arten oligo- bis polyphag. Im Rahmen dieser Studie konnten neue Nährpflanzenassoziationen zwischen Asianidia-Arten und Pflanzenarten der Lorbeerwälder Madeiras gefunden werden. Die Nährpflanzenspektren der nahe verwandten Arten A. albula und A. decolor zeigten große Ähnlichkeiten, während die systematisch weiter entferne Art A. insulana andere Nährpflanzen nützt. Möglicherweise spielte die unterschiedliche Nahrungspräferenz eine entscheidende Rolle inArtbildungsprozesen der Gattung Asianidia auf Madeira.Five Asianidia Zachvatkin species (Hemiptera, Cicadellidae) - A. albula, A. decolor, A. insulana, A. chrysanthemi and A. melliferae - were found in a survey of the leafhoppers associated with a patch of the laurel forest in Madeira island. A total of 513 specimens were collected as a result of a twoyear study. Asianidia decolor was the most abundant species (47%), followed by A. albula (36%) and A. insulana (16%). A. chrysanthemi and A. melliferae were scarcely found. These leafhoppers proved to be active mostly during spring and summer, but A. albula and A. decolor also showed a peak of abundance during November. The Asianidia species showed considerable variation in host-plant preferences, being some of them monophagous (A. chrysanthemi and A. melliferae), while others are oligophagous or even have a wide range of hostplants (A. albula, A. decolor and A. insulana). During this study new associations were found between these leafhoppers and plants of the Madeiran laurisilva. The host-plant spectra of the closely related Asianidia albula and A. decolor showed considerable overlap. On the contrary, A. insulana, a species of a different lineage, had different host-plants. It is possible that differences in the preference for host-plants might have played a key role in the diversification of Asianidia in the Madeiran laurisilva