Changes in the Vegetation, Soil Seed Bank and Soil Properties at Bait Sites in a Protected Area of the Central European Lower Montane Zone

Abstract

Feeding places for shooting wild boar (so-called bait sites) are spreading in some regions and they have a growing impact on natural ecosystems. Bait sites were investigated to detect the changes in vegetation, the soil seed bank and soil nutrients. The study area is situated in the Mátra Landscape Protection Area, representing a typical oak forest in the Central European lower montane zone (in Hungary). Two types of bait sites were selected: forests and clearings. A vegetation survey, a soil seed bank experiment and a soil analysis were conducted. The degree of degradation of vegetation was similar at the various bait sites, but only the abundance of weeds was higher in the clearings. The density of weed seeds in the soil varied regardless of type, clearly showing the effects of artificial seed sources. The number of weed species was, however, significantly higher in the clearings. The degree of Jaccard-similarity between the vegetation and the seed bank was the highest in the clearings. The dominance of long-term persistent seeds did not differ among bait sites, indicating frequent disturbances at these sites. The amount of soil nutrients was significantly (more than 10 times) higher in the clearings and this, along with their greater openness, may be responsible for the higher number of weed species in their seed banks. The vegetation and the soil of the clearings proved to be more degraded, mainly due to their habitat characteristics, but the seed bank was similarly infected in the less weedy forests; thus, all bait sites may equally be the focal points of a possible invasion. It means new challenges for the management, considering that climate change and the intensive logging and hunting activities can strengthen the effects of bait sites.