Sand dune - nitrogen inputs

Sand dunes soils are generally deficient in nutrients. Nitrogen is added in some instances where hydraulic reseeding is undertaken as a means of stabilising sand dunes. However, high nitrogen levels added during wet weather can become lethal when concentrations become elevated around the root system during dry periods (Ranwell & Boar 1986). There is some evidence to suggest that for many English sites, nitrogen (from airborne inputs) may increase the levels on sand dunes to a point where adverse changes in the vegetation take place (Centre for Ecology & Hydrology, No Date).

Evidence also exists from sand dunes in Holland of the effect of acid deposition and pollutants on the vegetation of sand dunes. Studies on the dune system on the former island of Voorne in the Netherlands, which were made over a period of 25 years suggested that the disappearance of sea-holly Eryngium maritimum and sea spurge Euphorbia paralias, both dependent on sand deposition, and the increase in sea-buckthorn Hippophae rhamnoides scrub was attributed in part to an increase in nitrogen levels (van der Laan 1985).

References

Centre for Ecology & Hydrology Changing nutrient budget of sand dunes: consequences for the nature conservation interest and dune management. Countryside Council for Wales.

Ranwell, D.S. & Boar, R. 1986. Coast Dune Management Guide. Institute of Terrestrial Ecology, NERC, 105 pp.

van der Laan, D. 1985. Changes in the flora and vegetation of the coastal dunes of Voorne (The Netherlands) in relation to environmental changes. In: Ecology of Coastal Vegetation, eds. W.G Beeftink, J. Rozema & A.H.L Huiskes.. Vegetatio, 61., 87-95.