02947nas a2200337   4500008004100000020001400041245012800055210006900183260000900252300001200261490000700273520183800280653006802118653002502186653002502211653005402236653001202290653001202302653001102314653003102325653004002356653001202396653001502408653002302423653002402446653004602470653002402516100001602540700001202556856004102568       1987                        eng d  a0036-757500aThe foliage-dwelling spider community of an abandoned grassland ecosystem in eastern Switzerland assessed by sweep sampling0 afoliagedwelling spider community of an abandoned grassland ecosy  c1987  a383-3890 v603 aThe foliage-dwelling spiders of an abandoned grassland ecosystem (Valeriano-Filipenduletum, Carex acutiformis Ehrh. type) in eastern Switzerland were studied from June to September by sweeping technique. A total of 632 adult specimens representing 22 identified species has been collected by sweeping (based on totally ca. 2000 single sweeps). More than two thirds of the sampled adult spiders were females. At all times, more immature than adult spiders were captured (overall, 83% immatures). Among the 3756 collected spiders (immatures plus adults), the six families Agelenidae, Araneidae, Micryphantidae, Pisauridae, Salticidae, and Tetragnathidae prevailed in the sweep net samples (combined ca. 90% of all spiders). The five speices Eyarcha arcuata (Clerck), Hylyphantes nigritus (Simon), Neottiura bimaculata (L.) Pisaura mirabilis (Clerck), and Tetragnatha extensa (L.)constituted combined > 80% of all adult spiders sampled by sweeping. The web-building spiders T. extensa and H. nigritus were the two species most frequently captured. Adults of large orbweaving spiders (Argiope bruennichi [Scopoli], Araneus quadratus Clerck, and Araneus diadematuss Clerck)were abundant in the investigated grassland habitat (assessed by web counts), but obviously underproportionately represented in the sweep net samples. Considering the total number of spiders (imatures plus adults) per 100 single sweeps, a strong increase from spring to late summer was noticed which is considered to be primarily due to egg-laying of them most dominant species in spring followed by hatching of the spiderlings in the course of the summer. Since spiders are abundant predators in this grassland ecosystem (ca. 0.1 m2 web area/m2 ground area, alone due to orb-weavers in August/Sept.), they may be important mortality agents of grassland arthropods.10a[Seasonal abundance / / Foliage dwelling community of abandoned10aabandoned grassland]10aAraneae (Arachnida).10aAraneae [Community structure / / Foliage dwelling10aEcology10aEurasia10aEurope10afoliage dwelling community10agrassland] [Grassland / / Abandoned10aHabitat10aLand zones10aPalaearctic region10aPopulation dynamics10astructure] [Switzerland / / Glatt River].10aTerrestrial habitat1 aNyffeler, M1 aBenz, G  u<Go to ISI>://ZOOREC:ZOOR12400068312