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Year-round grazing to counteract effects of atmospheric nitrogen deposition may aggravate these effects
2014
van Dobben, H.F. | Wamelink, G.W.W. | Klimkowska, A. | Slim, P.A. | van Til, M.
Excessive nitrogen input in natural ecosystems is a major threat to biodiversity. A coastal dune area near Amsterdam in the Netherlands suffers from high atmospheric nitrogen deposition affecting sensitive habitats such as fixed coastal dunes with herbaceous vegetation (‘grey dunes’). To mitigate its effect year round grazing was applied from 2007 until 2012. In winter, when natural food supply is low, the cattle received supplementary hay that caused additional inputs of nitrogen. Estimates based on nitrogen contents of hay, as well as of manure, showed the input through winter feeding (c. 3–14 kg N ha-1.y-1) is in the same order of magnitude as both the actual deposition (c. 17 kg N ha-1.y-1) and the critical load for a number of herbaceous habitat types (10–15 kg N ha-1.y-1). Locally, the effect of winter feeding adds to the effect of nitrogen redistribution within the area caused by the cattle's terrain usage. We conclude that winter feeding may aggravate effects of atmospheric nitrogen deposition. Keywords: Vegetation management; Manure; Nitrogen; Eutrophication; Natura 2000; Grey dune
Показать больше [+] Меньше [-]Year-round grazing to counteract effects of atmospheric nitrogen deposition may aggravate these effects
2014
van Dobben, H.F. | Wamelink, G.W.W. | Klimkowska, A. | Slim, P.A. | van Til, M.
Excessive nitrogen input in natural ecosystems is a major threat to biodiversity. A coastal dune area near Amsterdam in the Netherlands suffers from high atmospheric nitrogen deposition affecting sensitive habitats such as fixed coastal dunes with herbaceous vegetation (‘grey dunes’). To mitigate its effect year round grazing was applied from 2007 until 2012. In winter, when natural food supply is low, the cattle received supplementary hay that caused additional inputs of nitrogen. Estimates based on nitrogen contents of hay, as well as of manure, showed the input through winter feeding (c. 3–14 kg N ha-1.y-1) is in the same order of magnitude as both the actual deposition (c. 17 kg N ha-1.y-1) and the critical load for a number of herbaceous habitat types (10–15 kg N ha-1.y-1). Locally, the effect of winter feeding adds to the effect of nitrogen redistribution within the area caused by the cattle's terrain usage. We conclude that winter feeding may aggravate effects of atmospheric nitrogen deposition. Keywords: Vegetation management; Manure; Nitrogen; Eutrophication; Natura 2000; Grey dune
Показать больше [+] Меньше [-]Soil acidification in loess and clay soils in the Netherlands
2000
Salm, C. van der | Vries, W. de
Critical loads of sulphur and nitrogen for terrestrial ecosystems in Europe and Northern Asia influenced by different soil chemical criteria.
2008
Reinds, G.J. | Posch, M. | Vries, de, W. | Slootweg, J. | Hettelingh, J.P.
A critical load data base was developed for Europe and Northern Asia using the latest data bases on soils, vegetation, climate and forest growth. Critical loads for acidity and nutrient nitrogen for terrestrial ecosystems were computed with the Simple Mass Balance model. The resulting critical loads are in accordance with critical loads from previous global empirical studies, but have a much higher spatial resolution. Critical loads of acidity are sensitive to both the chemical criterion and the critical limit chosen. Therefore a sensitivity analysis of critical loads was performed by employing different chemical criteria. A critical limit based on an acid neutralizing capacity (ANC) of zero resulted in critical loads that protect ecosystems against toxic concentrations of aluminium and unfavourable Al/Bc ratios, suggesting that ANC could be an alternative to the commonly used Al/Bc ratio. Critical loads of nutrient nitrogen are sensitive to the specified critical nitrate concentration, especially in areas with a high precipitation surplus. If limits of 3¿6 mg N l¿1 are used for Western Europe instead of the widely used 0.2 mg N l¿1, critical loads double on average. In low precipitation areas, the increase is less than 50%. The strong dependence on precipitation surplus is a consequence of the simple modelling approach. Future models should explore other nitrogen parameters (such as nitrogen availability) instead of leaching as the factor influencing vegetation changes in terrestrial ecosystems.
Показать больше [+] Меньше [-]SO2 and NH3 deposition as possible causes for the extinction of Arnica montana L.
1992
Fennema, F. (Rijksinstituut voor Natuurbeheer, Arnhem (Netherlands))
Modeling study of SO(x) and NO(x) transport during the January 1985 smog episode
1990
Leeuw, F.A.A.M. de (Rijksinstituut voor Volksgezondheid en Milieuhygiene, Bilthoven (Netherlands)) | Rheineck Leyssius, H.J. van
Critical deposition levels for nitrogen and sulphur on Dutch forest ecosystems
1988
Vries, W. de (Stichting voor Bodemkartering, Wageningen (Netherlands))
Assessment of the exposure and loads of acidifying and eutrophying pollutants and ozone, as well as their, harmful influence on the vitality of the trees and the Speulder forest ecosystem as a whole
1998
Erisman, J.W. (Rijksinstituut voor Volksgezondheid en Milieuhygiene, Bilthoven (Netherlands).) | Draaijers, G.P.J. | Steingrover, E. | Dijk, H. van | Boxman, A. | Vries, W. de
Accumulation and leaching of the fungicide fentin acetate and intermediates in sandy soils
1990
Loch, J.P.G. (Rijksinstituut voor Volksgezondheid en Milieuhygiene, Bilthoven (Netherlands)) | Greve, P.A. | Berg, S. van der
Climate OptiOns for the Long term (COOL): interim phase report
1999
Berk, M.M. | Hordijk, L. | Hisschemoeller, M. | Kok, M.T.J. | Liefferink, D. | Swart, R.J. | Tuinstra, W.