Effects of sand movement by wind on nematodes and soil-borne fungi in coastal foredunes
In stabilized dunesAmmophila arenaria (marram grass) degenerates due to a process involving soil-borne pathogens and parasites. This leads to exposure of the sand surface so that wind erosion may create blowouts.Ammophila rejuvenates on the edges of the blowouts, where the sand has accumulated. We tested the hypothesis that such rejuvenation of plants may be related to a reduction of the plant-parasitic nematodes and fungal propagules during the process of wind-driven transport.
Field measurements in blowouts during storm events indicated that the drifted sand contained relatively low numbers of plant pathogenic fungi and plant-parasitic nematodes. A wind tunnel experiment showed that drifting sand may indeed reduce the numbers of fungi and nematodes. Although most fungi were attached to sand particles, they were also affected by the wind-borne sand movement. Sand that had been deposited by wind was made up of a larger proportion of large-sized particles. In our experiment the relatively small particles were lost during transport.
Stirring the soil (part of the forces of natural winds) by mixing for 15 min. with a propeller mixer at 1500 rpm significantly reduced the number of nematodes and fungi. Both sand movement in the wind tunnel and intensive stirring of the sand enhanced the growth ofAmmophila test plants in a bioassay. It was concluded that in wind-blown sand the pathogen inoculum is reduced. Therefore, serious consideration should be given to allowing controlled reactivation of blow-outs to rejuvenate decliningAmmophila in stabilized foredunes.
Implications for dune management are briefly discussed.
KeywordsAeolian transport Ammophila arenaria Blow-out Sand supply Rejuvenation Soil-borne disease
Nomenclaturevan der Meijden (1990) for vascular plants. Nematodes were identified to the genus level according to Bongers (1988) The allocation of nematodes to feeding groups was according to Yeates et al. (1993) Nomenclature of fungi according to Domsch et al. (1980) was used throughout this study except forFusarium Species of the latter genus were identified according to Nelson et al. (1983)
Unable to display preview. Download preview PDF.
- Bagnold, R.A. 1954. The physics of blown sand and desert dunes. 2nd ed. Methuen, London.Google Scholar
- Baye, P.R. 1990. Comparative growth responses and population ecology of European and American beachgrasses (Ammophila spp.) in relation to sand accretion and salinity. PhD. thesis, University of Western Ontario, London, Ont.Google Scholar
- Bongers, T. 1988. De nematoden van Nederland. Stichting Uitgeverij Koninklijke Nederlandse Natuurhistorische Vereniging, Utrecht.Google Scholar
- Carter, R.W.G., Hesp, P.A. & Nordstrom, K.F. 1990. Erosional landforms in coastal dunes. In: Nordstrom, K.F., Psuty, N. & Carter, R.W.G. (eds.) Coastal dunes. Forms and process, pp. 217–249. John Wiley and Sons Ltd, Chichester.Google Scholar
- Domsch, K.H., Gams, W. & Anderson, T.-H. 1980. Compendium of soil fungi. Vols. 1 & 2. Academic Press, London.Google Scholar
- Draga, M. 1983. Eolian activity as a consequence of beach nourishment-observations at Westerland (Sylt), German North Sea coast. Zeitschr. f. Geomorphol. 45: 303–319.Google Scholar
- Eisenback, J.D. 1993. Interactions between nematodes in cohabitance. In: Khan, M.W. (ed.) Nematode interactions, pp. 134–174. Chapman and Hall, London.Google Scholar
- Eisenback, J.D. & Griffin, G.D. 1987. Interactions with other nematodes. In: Veech, J.A. & Dickson, D.W. (eds.) Vistas on nematology: a commemoration of the 25th anniversary of the Society of Nematologists, pp. 313–320. Society of nematologists, De Leon Springs, FL.Google Scholar
- Gregory, P.H. 1961. Microbiology of the atmosphere. Leonard Hill, London.Google Scholar
- Hooper, D.L. 1986. Extraction of free-living stages from soil. In: Southey, J.F. (ed.) Laboratory methods for work with plant and soil nematodes. Reference book 402, pp. 5–30. Ministry of Agriculture, Fisheries and Food, Her MajestyÕs Stationary Office, London.Google Scholar
- Nelson, P.E., Toussoun, T.A. & Marasas, W.F.O. 1983. Fusarium species. An illustrated manual for identification. Pennsylvania State University Press, University Park, London.Google Scholar
- Oostenbrink, M. 1960. Estimating nematode populations by some selected methods. In: Sasser, J.N. & Jenkins, W.R. (eds.) Nematology, pp. 85–102. University of North Carolina Press, Chapel Hill, NC.Google Scholar
- Orr, C.C. & Newton, O.H. 1971. Distribution of nematodes by wind. Plant Disease Reporter 55: 61–63.Google Scholar
- Pluis, J.L.A. & de Winder, B. 1990. Natural stabilization. In: Bakker, T.W.M., Jungerius, P.D. & Klijn, J.A. (eds.) Dunes of the European Coasts. Catena supplement 18: 195–208.Google Scholar
- Ranwell, D.S. 1972. Ecology of salt marshes and sand dunes. Chapman and Hall, London.Google Scholar
- van der Meijden, R., Weeda, E.J., Adema, F.A.C.B. & de Joncheere, G.J. 1990. Heukels’ Flora van Nederland. 20th ed. Wolters-Noordhof, Groningen.Google Scholar
- van Dieren, J.W. 1934. Organogene Dünenbildung. Eine geomorphologische Analyse der Dünenlandschaft der West-Friesischen Insel Terschelling mit pflanzensoziologischen Methoden. Martinus Nijhoff, Den Haag.Google Scholar
- Warcup, J.H. 1960. Methods for the isolation and estimation of activity of fungi. In: Parkinson, D. & Waid, J.S. (eds.) The ecology of soil fungi, pp. 3–21. Liverpool University Press, LiverpooGoogle Scholar
- Willis, A.J. 1989. Coastal sand dunes as biological system. Proc. R. Soc. Edinb. 96B: 17–36.Google Scholar
- Yeates, G.W., Bonger, T., de Goede, R.G.M., Freckman, D.W. & Georgieva, S.S. 1993. Feeding habits in soil nematode families and genera. An outline for soil ecologists. J. Nematol. 25: 315–331.Google Scholar
- Zadoks, J.C. & Schein, R.D. 1979. Epidemiology and plant disease management. Oxford University Press, New York, NY.Google Scholar
- Zoon, F.C., Troelstra, S.R. & Maas, P.W.Th. 1993. Ecology of the plant-feeding nematode fauna associated with sea buckthorn (Hippophaë rhamnoides L. ssp. rhamnoides) in different stages of dune succession. Fund. Appl. Nematol. 16: 247–258.Google Scholar