Relationships of marsh seed banks to vegetation patterns along environmental gradients

• 1 The relationship of the seed bank to the vegetation of a freshwater marsh was studied along gradients of water depth and soil organic matter content. Characters examined included standing crop, seedling density, and species composition, distribution and richness.
• 2 The seed bank differed from the vegetation in that only nine of twenty-seven species were present in both, abundant seed-bank species were uncommon as adults, and adults showed different distributions along a gradient of soil organic matter content whereas their seeds were most abundant in soils with high organic matter.
• 3 The seed bank resembled the vegetation in that separate multivariate analyses of the communities revealed that variation in the species composition of each was significantly correlated with water depth and soil organic matter content. Further, species richness in both communities decreased with water depth and increased with soil organic matter content. Lastly, the standing crop of the vegetation and the number of seedlings both decreased with water depth and increased with soil organic matter.
• 4 Consideration of spatial patterns and environmental gradients revealed more similarities between vegetation and seed banks than were obtained by comparing species lists. The results suggest that artificial stimulation of seed bank germination for management purposes will not produce vegetation changes as large as those suggested by differences in species lists.