Seed Longevity in Calcareous Ecosystems

摘要

Calcareous lands play an important role in the gene reservoir persistence through soil seed bank (SSB). This research was carried out to assess soil seed bank dynamics (SSBDs) in a calcareous and a non-calcareous land in central Iran through time. Plot-based sampling was done at two times in 6 and 18 months after seed dispersal. Environmental and soil characteristics and diversity and germination indices (DIs, GIs) were measured for SSB. Multivariate ordination (CCA) and liner regression was performed to detect relationship between SSBDs and soil factors. Nitrogen (N), organic matter (OM), phosphorous (P), and soil moisture (SM) affected SSBDs in short time and lime content had a positive effect in persistent SSB in long time, especially in grasses (Sig. < 0.05). In calcareous soil, the lime content showed a positive relation with GIs, where has led to an inducible seed dormancy and preserved vigor index (VI) {R-2 = 0.67 and 0.45 in grasses and forbs, respectively} after 18 months.