The impact of nitrogen deposition on acid grasslands in the Atlantic region of Europe
2011
Stevens, Carly J. | Duprè, Cecilia | Dorland, Edu | Gaudnik, Cassandre | Gowing, David J.G. | Bleeker, Albert | Diekmann, Martin | Alard, Didier | Bobbink, Roland | Fowler, David | Corcket, Emmanuel | Mountford, J Owen | Vandvik, Vigdis | Aarrestad, Per Arild | Muller, Serge | Dise, Nancy B.
A survey of 153 acid grasslands from the Atlantic biogeographic region of Europe indicates that chronic nitrogen deposition is changing plant species composition and soil and plant-tissue chemistry. Across the deposition gradient (2–44 kg N ha⁻¹ yr⁻¹) grass richness as a proportion of total species richness increased whereas forb richness decreased. Soil C:N ratio increased, but soil extractable nitrate and ammonium concentrations did not show any relationship with nitrogen deposition. The above-ground tissue nitrogen contents of three plant species were examined: Agrostis capillaris (grass), Galium saxatile (forb) and Rhytidiadelphus squarrosus (bryophyte). The tissue nitrogen content of neither vascular plant species showed any relationship with nitrogen deposition, but there was a weak positive relationship between R. squarrosus nitrogen content and nitrogen deposition. None of the species showed strong relationships between above-ground tissue N:P or C:N and nitrogen deposition, indicating that they are not good indicators of deposition rate.
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