- TRAMPLING AND VEGETATION RECOVERY IN SOME FOREST AND HEATH COMMUNITIES - 111 Applied Vegetation Science 7: 111-118, 2004 © IAVS; Opulus Press Uppsala. Abstract. Over the past decades outdoor recreation has be- come progressively more important and as a result human- induced potential damage has increased. In this study, short- term effects – a 2-yr period – of human trampling on some common forest and heath communities in Central Belgium were studied experimentally. Vulnerability to disturbance was compared among plant communities in terms of resistance, resilience and tolerance, which are based on cover measure- ments. The herb layer of the examined mesophilous forest communities appeared to be more sensitive than the heath and dry forest community, which were dominated by more resist- ant graminoid (Molinia caerulea, Deschampsia flexuosa) and dwarf-shrub species (Vaccinium myrtillus, Calluna vulgaris, Erica tetralix). The analysis showed that site structure and vegetation were already affected by low intensities of tramp- ling, while vegetation recovery during the first year after trampling was limited in most plant communities. Recovery during the second year in vegetation cover as well as height was most pronounced in mesophilous forest communities. Occasional trampling clearly can lead to increased visual evidence of previous use and continued recreational distur- bance. Therefore management plans should discourage hiking activity off paths and restrict recreation activities to the least vulnerable communities. Keywords: Resilience; Resistance; Trampling experiment; Vegetation destruction. Nomenclature: Lambinon et al. (1998). Abbreviations: RVC = Relative vegetation cover; RVH = Relative vegetation height. Introduction In recent decades, recreation intensity has increased considerably, resulting in a growing pressure on pro- tected areas. As trampling is assumed to be one of the main features of tolerated recreation activity in nature reserves, we focus on its direct and indirect effects on vegetation. Direct effects include mechanical damage to plant tissue, whereas indirect effects are mainly a result of soil compaction (Liddle 1997). Besides trampling on designated paths, occasional trampling is in many areas a growing concern for man- agers. We are specifically interested in the effects of occasional trampling by recreationists hiking off paths (Bright 1986; Ikeda & Okutomi 1992; Gallet & Rozé 2002) and the short-term influence of these effects on visual evi- dence of previous use. Visual indications of previous use encourage additional and continued disturbance. Vulnerability of plant communities subjected to tram- pling is determined by their ability to resist trampling impact and/or to recover after cessation of the impact. This twofold ability has been quantified in indices for resistance, resilience (Kelly & Harwell 1990; Kuss & Hall 1991) and tolerance. The research questions of the present study are: 1. How do vegetation characteristics such as cover, height and species richness respond to different intensi- ties of trampling and how do changes arise during the following two years? 2. Can we differentiate between relative vulnera- bility of plant communities in terms of resistance and recovery of vegetation cover? To study recovery processes towards the initial state, we used the approach of experimental trampling over a short period of time with no prolonged disturbance. As a result, temporally variable influences as caused by weather variations could not interfere with disturbance effects of trampling. This method allows comparison of the damage to species and communities by specific amounts of trampling (cf. Bayfield 1979) as well as the implicit relationship between intensity of use, vegetation deterioration and the vulnerability of plant communities. Experimental trampling and vegetation recovery in some forest and heathland communities Roovers, P. * ; Verheyen, K.; Hermy, M. & Gulinck, H. Laboratory for Forest, Nature and Landscape Research, Katholieke Universiteit Leuven, Vital Decosterstraat 102, B-3000 Leuven, Belgium; * Corresponding author; Fax +3216329760; E-mail pieter.roovers@agr.kuleuven.ac.be; Web http://www.agr.kuleuven.ac.be/lbh/lbnl/ecology