This paper investigates the impact of a 100-year flood in May 1999 on community composition and large woody debris standing stock in an alpine floodplain (Isar, Germany). Detailed pre-flood data sampled from 1993 to 1998 are compared with the situation directly after the flood. In those parts of the Isar floodplain mainly covered with pioneer vegetation prior to flooding, the coverage of unvegetated gravel bars increased by 22% following the flood. However, the flood did not remove larger amounts of older successional vegetation stages (willow thickets, floodplain forest). No significant changes in the benthic invertebrate fauna were recorded. The lowest densities of riparian ground beetles (Carabidae) within the study were recorded one month after the flood. Two months later, the ground beetle densities increased to the highest values ever recorded, indicating the ground beetle's high potential for recolonization. These results highlight the degree of resilience of both the aquatic and the riparian invertebrate fauna. The flood also caused a significant increase in large woody debris standing stock; in one section the number of logs increased tenfold and the volume increased by a factor of 20, leading to the assumption that most woody debris in alluvial flood-plains is provided by catastrophic events.

Riparian sand and gravel banks are inhabited by a fauna that is well adapted to varying river water levels and frequent inundation of the banks. Arthropods found in these habitats were studied from November 1998 to January 1999 in the upper and lower floodplains of the main rivers and tributaries in ten major catchments in the Victorian Alps. Wolf spiders (Lycosidae, 68%) and ground beetles (Carabidae, 7.8%) were the most abundant arthropods, with densities averaging 14.6 ± 1.8 (s.e.) and 2.3 ± 0.4 individuals m–2 respectively. Species composition and wolf spider densities changed substantially between upland and lowland rivers. These differences correspond with changes in altitude, shading, and gravel and gravel bank size. Comparison of our results with similar studies conducted in temperate Northern Hemisphere floodplains showed significant differences. Carabidae, not Lycosidae, are the dominant arthropod group in Northern Hemisphere floodplains. Wolf spider densities are higher in upper than lower reaches of rivers in the Victorian Alps, but do not change along rivers in the Northern Hemisphere. In contrast, carabid beetles showed similar densities between upland and lowland floodplains in Victoria, but increase in density along rivers in the Northern Hemisphere. A second, monthly sampling program on gravel banks along the Avon River (Gippsland) over a one-year period in 1996 and 1997 provided information on the life histories of eight common gravel-bank arthropods: Venatrix lapidosa, V. arenaris, two undescribed Artoria species (‘A’, ‘B’) (Lycosidae), Eudalia macleayi, Elaphropus ovensensis, Perileptus constricticeps and an unidentified Loxandrus species (‘B’) (Carabidae). Artoria sp. A and sp. B are diplochronous. Despite its smaller size, Artoria sp. B matured one month after Artoria sp. A. Lower temperatures at upland streams and rivers, the typical habitat for Artoria sp. B, may delay its development in comparison with Artoria sp. A, which is generally found further downstream. The life histories of both lycosid spiders and carabid beetles, characterised by prolonged reproductive period and short larval development, appear to have some adaptive value in regard to the disturbance-prone environment.

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The role of the life cycle for the survival of the riparian wolf spiders Pardosa wagleri (HAHN, 1822) and Pirata knorri (SCOPOLI, 1763). Quantitative, time-limited samplings in monthly intervals from June 1995 to August 1996, in combination with the measurement of carapace width of juvenile and adult spiders has revealed the life cycle patterns of the riparian wolf spiders Pardosa wagleri and Pirata knorri and showed the effect of floods on their abundance at the Isar River (Germany, Bavaria). Adults and juvenile spiders are heavily affected by floods but the populations of both species are able to recover quickly. The life cycles of both species are synchronized with the season and display a spring/summer stenochrony. P. wagleri shows a second reproductive phase in early summer. This reproductive behaviour supports the persistence of populations in this disturbed environment.

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Für den deutschen Wandertourismus waren selbst die Krisenjahre erfolgreich. Das Wandern boomte so stark, dass sogar Wanderwege wegen Überfüllung gesperrt oder der Zugang zu ihnen reglementiert werden musste. Haben wir die Natur und das Draußen-Sein in unmittelbarer Nähe wiederentdeckt? „Wandern zwischen Outdoorboom und Klimawandel“ – unter dieser Perspektive beleuchten Forschende und Praktiker neueste Entwicklungen und Fragestellungen im Wandertourismus. Ein hochaktuelles Werk, das im Rahmen eines Symposiums zum 10-jährigen Jubiläum der Arbeitsgruppe Wanderforschung an der Ostfalia Hochschule entstand und innovative Impulse und Forschungsansätze für die wandertouristische Praxis bündelt.