Irl, S; Steinbauer, M; Babel, W; Beierkuhnlein, C; Blume-Werry, G; Messinger, J; Palomares-Martínez, A; Strohmeier, S; Jentsch, A: An 11-yr exclosure experiment in a high-elevation island ecosystem: Introduced herbivore impact on shrub species richness, seedling recruitment and population dynamics, Journal of Vegetation Science, 23(6), 1114-1125 (2012), doi:10.1111/j.1654-1103.2012.01425.x
Abstract:

Questions Do introduced herbivores and fire explain the mono-dominance of one legume shrub (Adenocarpus viscosus ssp. spartioides) above the tree line on an oceanic island given the fact that a number of other legume shrub species are potentially present? What drives the observed landscape scale life-death pattern within the mono-dominant shrub species population?
Location The subalpine scrub vegetation of La Palma (Canary Islands, Atlantic Ocean).
Methods An eleven-year exclosure experiment with sites distributed along an elevation and orientation gradient was used to identify the influence of introduced herbivore pressure on four endemic shrub species and their seedling recruitment. Further, we assessed the population dynamics and spatial pattern of the dominant shrub species A. viscosus ssp. spartioides. Habitat and vitality characteristics were investigated assessing spatial topographic features and tree ring based age estimates. Linear mixed models, ANOVA’s, linear regression and variation partitioning were used as statistical analysis tools.
Results Outside of the exclosures A. viscosus ssp. spartioides was virtually mono-dominant in the study area, even though other shrubs species seem better suited in the absence of introduced herbivores. The presence of introduced herbivores significantly reduced seedling recruitment within all target species, except for A. viscosus ssp. spartioides. Mean age of A. viscosus ssp. spartioides increased with elevation, although vitality analyses indicated that the subalpine scrub is elevated above its growth optimum. Three out of four investigated shrub species showed differences in growth height depending on elevation and island orientation.
Conclusion Introduced herbivores and fire are identified as key disturbances enhancing A. viscosus ssp. spartioides, a commonly less competitive species. However, Genista benehoavensis, a single island endemic shrub species, seems to be better adapted to the harsh climatic conditions of the subalpine scrub in the absence of introduced herbivores than any other shrub species.

Aktuelle Termine



BayCEER-Kolloquium:
Do. 14.11.2019
Analysis of ozone formation and trend over northern Bavaria by using stochastic and deterministic models
Do. 21.11.2019
Quantification of subsurface properties using the groundwater response to Earth and atmospheric tides
Konferenzen:
Fr. 22.11.2019
Geoökologie-Tagung 2019
Universitäts-Forum Bayreuth:
Mi. 13.11.2019
Bayreuther Innenstadt und Rotmaincenter: Freund oder Feind? - Betrachtungen aus der Perspektive der Besucher
Vortrag:
Fr. 15.11.2019
Changing the game in Earth Observation - The European Union’s Copernicus programme -
BayCEER Blog
24.05.2019
Stoichiometric controls of C and N cycling
07.05.2019
Flying halfway across the globe to dig in the dirt – a research stay in Bloomington, USA
07.05.2019
EGU – interesting research and free coffee
16.04.2019
Picky carnivorous plants?
RSS Blog als RSS Feed
Wetter Versuchsflächen
Luftdruck (356m): 964.4 hPa
Lufttemperatur: 5.3 °C
Niederschlag: 0.4 mm/24h
Sonnenschein: 2 h/d
Wind (Höhe 17m): 9.7 km/h
Wind (Max.): 20.9 km/h
Windrichtung: S

...mehr
Globalstrahlung: 184 W/m²
Lufttemperatur: 1.9 °C
Niederschlag: 0.4 mm/24h
Sonnenschein: <1 h/d
Wind (Höhe 32m): 11.8 km/h

...mehr
Diese Webseite verwendet Cookies. weitere Informationen