The ecological response of forest ground flora and soils to experimental trampling in British urban woodlands

Abstract

The ecological impact of recreation in woodlands and forests is now a subject of considerable world-wide interest. However, there are few studies examining the effects of recreation on woodland vegetation and soils in Britain. This paper quantifies the impact of controlled experimental trampling on three different woodland ground flora stands in lowland urban fringe W10 Quercus robur—Pteridium aquilinum—Rubus fruticosus woodlands (Rodwell, J.S. (1991) British Plant Communities I: Woodland and Scrub. Cambridge University Press) near Coventry, West Midlands. Relationships of plant cover, plant height and soil compaction with trampling in homogeneous stands of Hyacinthoides non-scripta (bluebell), Pteridium aquilinum (bracken) and Rubus fruticosus agg. (bramble) were curvi-linear, suggesting that rates of damage were most rapid at the initial stages of trampling. By virtue of its rosette growth form, the most resistant stand type was the Hyacinthoides stand. Least resistant was the Pteridium stand, but both the Pteridium and the Rubus stands were able to recover well from heavy levels of trampling by the following year. The ability of ground flora to tolerate impacts was more a function of an ability to recover from trampling, rather than to resist. Trampling had the most profound impact on the ability of Hyacinthoides non-scripta to produce seeds, and even two years after the cessation of impact, samples that had received one season of 500 passes had still not produced any seed bearing scapes. The carrying capacity of woodlands in terms of visitor numbers was lower than previously thought, with only 35 people permitted in stands dominated by Hyacinthoides, rising to 450 and 500 people in woodlands dominated by Rubus and Pteridium stands respectively. Models summarising these ecological changes are provided, along with applied recommendations to help manage urban sites with recreation and conservation in mind.