Questions: Does the increased atmospheric deposition of nitrogen, which can have major effects on the established vegetation of nutrient-poor habitats, also impact germination from the soil seed bank?
Location: Coastal dune slacks at Newborough Warren, Wales, UK.
Methods: The effects of nitrogen addition (15 kg.ha−1.a−1) on seed germination from the soil seed bank were investigated using the seedling emergence method between September 2004 and February 2005.
Results: More seedlings emerged from fertilised samples than unfertilised controls. Most species showed enhanced germination after fertilisation with nitrogen, with seedling numbers statistically significantly greater in nitrogen addition samples in a quarter of species abundant enough for analysis. Species that responded positively to fertilisation were species with low Ellenberg indicator values indicative of infertile sites.
Conclusions: Most species showed increased germination after fertilisation with nitrogen, including early successional species normally growing in nutrient-poor conditions. This suggests that the increased atmospheric deposition of nitrogen probably not only impacts on established vegetation, but also has the potential to alter seed bank dynamics.
Nomenclature: Stace (1997).