Seed Bank Dynamics in a Mediterranean Grassland

Abstract

JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact support@jstor.org.. British Ecological Society is collaborating with JSTOR to digitize, preserve and extend access to Journal of Applied Ecology. Summary 1. Changes in the seed bank, seedling emergence and plant density of the most common grass species, and all legume species, were monitored in a grassland in north Syria from October 1986 to May 1989. 2. The seed bank was greatest in May-June, following pasture maturity, then declined to its minimum in March-April. Losses of seeds during summer were mainly due to sheep grazing, while losses in winter and spring were mainly due to germination, although some seeds were eaten by soil fauna and some seeds died. The seed bank, particularly of the small-seeded species (Trifolium tomentosum and T. campestre) was greater under the high stocking rate than under the low stocking rate. 3. There was little seed carry-over of grasses from season to season (Avena spp. 5%, Heteranthelium piliferum 1%, Bromus spp. 0%), but seed carry-over was greater in legumes (Trifolium stellatum 27%, T. campestre 35%, and T. tomentosum 38%). Most seedlings emerged in the autumn, but emergence continued throughout the growing season. Plant density within each year reached a peak in January, declining as spring approached. 4. The ecological and agricultural importance of seed banks in native Mediterranean grasslands is discussed.

Soil seed banks, habitat heterogeneity, and regeneration strategies in a Mediterranean coastal sand dune

“…These germinability trends indicated high and low potential for producing persistent seed banks in these functional groups. These results are consistent with other studies from the Mediterranean region that showed that legumes and crucifers formed persistent seed banks, while grasses have little seed carry-over between years (Russi et al, 1992;Peco et al, 1998;Sternberg et al, 2003). Taxonomic similarities in seed morphology (e.g., seed coat impermeability in legumes) or physiological mechanisms of germination control may explain the homogeneity in dormancy trends within each group.…”

Soil Seed Bank and Aboveground Vegetation in Grazing Lands of Southern Marmara, Turkey

“…Research has shown that annuals are a major component of Mediterranean grasslands (Marcelo et al, 2003). The grazing of Mediterranean grasslands can have a large impact on vegetation (Montalvo et al, 1993;Seligman, 1996;Lavorel et al, 1999;Sternberg et al, 2000); however, the soil seed bank may buffer the impact of differences in inter-annual grazing (Russi et al, 1992;Ortega et al, 1997). It is generally assumed that Mediterranean annuals show adaptive responses to unpredictable environments by producing dormant seeds that persist during periods of limited resources (Shmida and Ellner, 1984;Thompson, 1992;Lavorel et al, 1993;Perevolotsky and Seligman, 1998).…”

Soil Seed Bank and Plant Community Development in Passive Restoration of Degraded Sandy Grasslands

“…Previous studies of passive restoration in degraded ecosystems have found that passive restoration had positive [14][15][16][17], neutral [18], or even negative effects [19] on the species composition and density of the soil seed bank, as well as on the species composition, density, coverage, and mean height of vegetation. The different results mainly depended on the variety in seed production and emergence capacity, plant growth and dispersal, and the ratio of weeds to grass across the different grasslands [15].…”