Recruitment of fleshy‐fruited species under different shrub species: Control by under‐canopy environment

Abstract

Seedling densities and the mortality of fleshy‐fruited species under 10 European tall‐shrub species and the tree Sorbus aria were analyzed in 10‐year‐old experimental scrub for one growing season. The mean total densities of seedlings of 18 fleshy‐fruited species differed under the different ‘hosts’, being highest under Crataegus monogyna, Viburnum opulus and Rosa canina (24–20 m−2); intermediate under Sorbus aria, Rhamnus catharticus, Cornus sanguinea, Ligustrum vulgare and Juniperus communis (17–12 m−2); and lowest under Euonymus europaeus, Viburnum lantana and Prunus spinosa (10–9 m−2). This ranking was similar for the 11 planted species and for nine bird‐dispersed, non‐planted species which invaded the site, notably Hedera helix and Solanum dulcamara. Within the experimental scrub as a whole mortality of seedlings differed significantly among species, being highest in those with the smallest number of recruits. Mortality ranged from 94% and 89% for Solanum dulcamara and Viburnum opulus to 26% for Hedera helix and Ligustrum vulgare. The mean mortality across all species of seedlings did not differ significantly between host species, although it was slightly higher under Juniperus and Cornus (56%, 53%) and lower under Viburnum lantana and Rhamnus (42%, 41%). In four species, the mortality of seedlings was significantly higher under conspecific adults. Mean topsoil water content after a dry spell was negatively correlated with the diffuse site factor (DSF). The mean density of accumulated seedlings of the most abundant seedling species (Hedera) was positively correlated with the topsoil water content. Densities of other species showed no strong correlations with either topsoil water content or DSF. The probable factors controlling recruitment are discussed.

Seed dispersal in six species of terrestrial orchids in Biebrza National Park (NE Poland)

“…Most information is derived from mathematical models or experiments in special wind tunnels [3,6,[15][16][17][18][19][20]. Data from field observations testing seed dispersal is very scarce, and mostly focused on seeds dispersed by animals, mainly in fleshy-fruited plants [21][22][23][24][25]. Genetic methods, based both on parentage analysis, fine-scale spatial genetic analysis and assignment tests, have also been used to assess the relative contributions of seed dispersal to gene flow [1,10,12,13,[26][27][28][29][30].…”

Radial growth response of Hedera helix to hydrological changes and climatic variability in the Rhine floodplain

“…Common Ivy (Hedera helix) develops vigorously in shady moist sites on fertile soils, but also has a considerable ecological tolerance to light and drought (Hoflacher and Bauer, 1982;Ellenberg, 1988;Grime et al, 1988;Kollmann and Grubb, 1999;Sack and Grubb, 2002;Sack et al, 2003a,b;Laskurain et al, 2004). As a lauriphyllous element of tertiary flora, ivy is limited in its range by low winter temperatures (Godwin, 1975;Quézel and Médail, 2003).…”

The combined impacts of deep shade and drought on the growth and biomass allocation of shade-tolerant woody seedlings

“…Streng et al 1989;Barton 1993;Burslem 1996;Walters and Reich 1997;Kollmann and Grubb 1999). Given information of survival rates (see, for example, Kobe 1999), this knowledge will allow prediction of seedling performance at given microsites.…”

“…Hedera is also native to forest and scrub in central and northern Europe, along with V. opulus and V. lantana (Rodwell 1991). These species' relative performances in the field probably depend on irradiance, soil nutrient concentrations and water supply (Grubb et al 1996;Kollmann and Grubb 1999).…”