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| Identifier |
000369301 |
| Title |
Μελέτη της επίδρασης της αστικοποίησης στις βιοκοινότητες των εδαφικών αραχνών (ARANEAE: GNAPHOSIDAE) στο νομό Ηρακλείου, Κρήτη |
| Alternative Title |
Effects of urbanization on ground spiders (ARANEAE: GNAPHOSIDAE) along an urban-rural gradient in Heraklion, Crete |
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Author
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Παναγιώτου, Ελένη
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Thesis advisor
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Μυλωνάς, Μωυσής
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| Abstract |
Global urbanization is a major force that causes alteration and loss of natural habitats. Urbanization creates habitats that exhibit considerably similar patterns throughout the world. Urban ecology is ecological research done in cities and towns. Urban ecosystems are strongly affected by humans and there is a continuum of decreasing human influence from city centers to wilderness. To study ecological changes along this continuum, researchers introduced the urban-rural gradient approach. The urban area (city center) refers to a densely populated, built-up, developed and often highly disturbed area that is surrounded by areas of decreasing development and habitation with moderate (suburban area) or light disturbance (rural area) level. The majority of the published papers studying the effects of urbanization on biodiversity investigated the ground beetles (Coleoptera: Carabidae). Studies analyzing other target invertebrates are limited. The aim of the study was to determine whether urbanization influences the biodiversity of ground spiders in the city of Heraklion in Crete. This study applies the urban-rural approach using the standardized methodology (pitfall trapping) as described by the Globenet project. Trapped spiders were collected monthly from November 2009 to the end of November 2010. The results supported the increasing disturbance hypothesis. Diversity, species richness and total spider abundance was lower in the urban areas, and higher in the rural areas. Our results supported the proposition that increased urbanization is associated with increased dominance. In the urban center a cosmopolitan and introduced species (Urozelotes rusticus) dominated. Furthermore the abundance of native species decreased from the rural area to the urban one, where cosmopolitan species gain dominance. Body size distributions of the urban sites appeared similar to the suburban and rural sites. Larger spiders dominated in the urban center as much as in suburban and rural areas. Thus the “Decreasing body size hypothesis” was not supported. This pattern was mainly caused by the dominance of the large species Urozelotes rusticus in the city.
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| Language |
Greek |
| Subject |
Abundance |
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Biodiversity |
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Disturbance |
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Species richness |
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Αραχνοπανίδα |
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Βιοποικιλότητα |
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Σωματικό μέγεθος |
| Issue date |
2011-11-18 |
| Collection
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School/Department--School of Sciences and Engineering--Department of Biology--Post-graduate theses
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Type of Work--Post-graduate theses
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| Views |
228 |
Μελέτη της επίδρασης της αστικοποίησης στις βιοκοινότητες των εδαφικών αραχνών (ARANEAE: GNAPHOSIDAE) στο νομό Ηρακλείου, Κρήτη
