Data/hora: 10/06/2024 14:17:55

Provedor de dados: | 16
País: | Netherlands
Título: | Trends in dragonfly occurrence in Belgium (Odonata)
Autores: | Knijf, G. de; Anselin, A.; Goffart, P.
Data: | 2003
Ano: | 2003
Palavras-chave: | Odonata; Dragonflies; Belgium; Atlas; Hot spot; Abundance class shift; Habitat; 42.75.
Resumo: | Trends in dragonfly occurrence in Belgium (Odonata)   The group ‘Gomphus’ collected 65 000 records of 69 species of Odonata, more or less equally scattered over Belgium. The best-investigated areas are the northern part and some river valleys in the south. Most hot spots can be found in the northeastern part, with a maximum of 48 species for 25 km². Remarkable is the fact that 50% of the species occurs in less than 7% of the 5 km grid cells (UTM). We determined trends in occurrence by comparing three periods: before 1950, 1950-1989 and 1990-2000. Four species show a clear decline over the three periods, eight species give evidence of a historical decline but survive on a limited number of sites and eight species also display a historical decline but have been increasing during the last decade. Six species show a (very) clear increase over the three periods and two species display their increase only during the last ten years.
Tipo: | Article in monograph or in proceedings
Identificador: | http://www.repository.naturalis.nl/record/219852
Editor: | European Invertebrate Survey - the Netherlands
Formato: | application/pdf
Fonte: | (c) Naturalis