Effects of nitrogen deposition on soil and vegetation in primary succession stages in inland drift sands

Abstract

Background and aims: Primary succession was studied in acid inland drift sands. Main research questions were: 1) How do vegetation and soil change during succession? 2) How are soil parameters and species abundance affected by atmospheric nitrogen deposition?Methods: One hundred sixty-five plots were selected in 21 drift sands throughout The Netherlands, divided over eight succession stages from bare sand to dry heath and within a gradient in nitrogen deposition. Vegetation development and soil parameters were described and water-extractable elements measured and differences between high (>30 kg N ha -1 year -1) and lower nitrogen deposition sites calculated. Results: Vegetation cover and height increased during succession. Lichens contributed most to plant species diversity. Thickness of A h horizon increased and pH decreased and concentrations of Fe, Al, S increased. Base cations increased as well, despite the drop in pH. Also, water-extractable ammonium, nitrate and phosphate increased, along with the NH 4:NO 3 ratio. Sites with high nitrogen deposition had higher NH 4:NO 3 and Al:Ca ratios, lower pH, higher cover of algae, lower lichen and total species diversity, more Pinus sylvestris seedlings and more species of late succession stages. Conclusions: Drift sand succession seems to be mainly driven by an increase in organic matter, but is accelerated by nitrogen deposition. © 2011 The Author(s).