Sand Dune Ecology

Vegetation succession has been investigated in relation to the introduction of exotic species and the dispersal ability of both native and non-native woody plant species. Following the introduction of myxomatosis and the subsequent rabbit population crash, sea buckthorn (Hippophae rhamnoides) has rapidly spread through the dunes to form large monotypic stands. The rate of spread has declined in recent years due to increased grass competition and a reduction in areas of bare sand. Wherever there is an ample supply of propagules, sea buckthorn stands are replaced by a number of shrub and tree species.

The findings are reported in detail in the following two sections:

• Sycamore invasion of sand dune systems. (100k)
• Patterns of invasion and succession by shrubs and trees on Portstewart dunes.

The impact of sea buckthorn on sand dune ecosystem has been investigated (see Binggeli et al. 1992 for details). The shrub's main impacts are:

• to alter the soils chemical properties.
• to facilitate the formation of woodland including a mixture of native and non-native species.
• to change the composition of mesofauna and ground beetle communities.