Tidal freshwater wetland zonation: seed and seedling dynamics

Abstract

Zonation patterns of seed rain (input), persistent seed bank (seeds persisting for 1 year or longer), field seedlings, and seed production were studied in a New Jersey tidal freshwater wetland along transects extending from a tidal stream bank 30 m into the high marsh. Species diversity was highest along the stream channel and lowest at the farthest high marsh sites. Seed rain and persistent seed bank densities were similar across the transect. Although species composition varied considerably among life history categories, generally field seedlings mirrored the species composition of the seed rain. Seed rain, seed bank, seedlings observed in the field, and seed production patterns varied between species, across sites for a species, and between years. Sites varied in the proportion of estimated seed production represented as seedlings either in greenhouse (5-99%) or field (2-24%) samples. Tidal transport influenced dispersal of seeds and the persistent seed bank.