Soil seed banks in primary and secondary deciduous forest in Białowieża, Poland

Abstract

Germination over 3 years was followed in 25 soil samples of 31 x 31 x 5 cm each from primary and secondary stands in Bialowieza forest, Poland. The number of seedlings emerging and the number of species declined over the 3 years. In year 1 the mean densities of emerging seedlings for the primary and secondary stands were similar (2142 rrr 2 and 2488 rrr 2 respectively); in year 3 the difference was greater (248 vs 498 rrr 2 ) but not statistically significant. The trend reflected the greater longevity of the seed bank species characteristic of the secondary forest. Two functional groups of herb and shrub species were distinguished in the seed bank based on (a) frequency as adults in the present vegetation, and (b) relative abundance in the seed banks of primary and secondary forest. Group A species need large-scale gaps in the tree canopy; most have very small seeds (<0.15 mg mean dry mass) and are very persistent in the soil. Group B species benefit from single-treefall gaps in the tree canopy, but appear to be suited primarily to gaps in the canopy of the herb layer and in the root layer made mainly by animals; their seeds are not as small (mostly >0.15 mg) and not as persistent in the soil. Group B species made up 86% of the seedlings emerging over 3 years in soil from the primary stand, and 56% of those from the secondary stand. In the laboratory all five Group B species tested showed some inhibition of germination in darkness, but only one showed unequivocal inhibition by far-redenrichment of low irradiance light.

The seed bank in an old-growth, temperate deciduous forest

“…Olmsted and Curtis (1947) report 10 species in the seed bank of a 50-year-old Fagus-Betula-Acer forest (215 seeds·m -2 ), and 12 in a 110-year-old forest (990 seeds·m -2 ). Previous studies have reported 8-51 species in the seed bank of mature, temperate deciduous forests, with most forests at the lower end of this range (Moore and Wein 1977;Graber and Thompson 1978;Staaf et al 1987;Matlack and Good 1990;Kjellsson 1992;Schiffman and Johnson 1992;Eriksson 1995;Smallidge and Leopold 1995;Jankowska-B»aszczuk and Grubb 1997;JankowskaB»aszczuk et al 1998). We found at least 38 different forest taxa in the seed bank at Mont St. Hilaire, and another 11 weedy species from the surrounding, nonforested landscape.…”

“…We conclude that the seed bank at Mont St. Hilaire as a whole is rich in species compared with that in most other temperate forests, and certainly richer than the seed banks reported in earlier stages of forest succession. We suspect that two factors contribute to this high species diversity in the seed bank at Mont St. Hilaire: (i) the diversity of habitats within this large tract of old-growth forest (Pickett and McDonnell 1989;Beatty 1991;Ashton et al 1998) and (ii) the natural disturbance regime in this high latitude deciduous forest (Pickett and McDonnell 1989;Thompson 1992;Jankowska-B»aszczuk and Grubb 1997). The composition of the seed bank clearly varies with environmental conditions, and the range of environmental regimes represented at Mont St. Hilaire is substantial (Maycock 1961;Enright and Lewis 1985).…”

Endozoochory by European bison influences the build-up of the soil seed bank in subcontinental coniferous forest

“…In most seed bank studies, animals are taken into consideration only as factors causing seed mortality (e.g. Leck et al 1989;Brown and Venable 1991;Thompson et al 1997;Hulme 1998), seed burial (Vander Wall 1993) or vegetation disturbances allowing the breaking of seed dormancy (Jankowska-Błaszczuk and Grubb 1997). It needs to be emphasized that the dung of large herbivores contains vast numbers of viable seeds of many vascular plant species (e.g.…”

Effect of Changes in Land Use During the 20th Century on Woodland and Calcareous Grassland Vegetation in Southern Poland

“…Recent studies have shown that natural regeneration of woodland communities is very slow and it is possible only in sites immediately adjacent to ancient woodlands -the sources of woodland species diaspores (PETERKEN, GAME 1984;DZWONKO 1993;DZWONKO, GAWROŃSKI 1994;MATLACK 1994;BRUNET, VON OHEIMB 1998;BOSSUYT, HERMY 2000). The soil seed banks cannot be sources of diaspores even in the sites agriculturally used for a short period since a majority of the woodland vascular plant species form only transient or short-term persistent seed banks and their seeds do not survive in the soil longer than few years (JANKOWSKA-BŁASZCZUK, GRUBB 1997;BEKKER et al 1998).…”